UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington D.C. 20549

FORM20-F

(Mark One)

OR

For the fiscal year ended December 31, 20172018

OR

For the transition period from                    to                    

OR

Date of event requiring this shell company report

Commission file number:001-36815

Ascendis Pharma A/S

(Exact name of Registrant as specified in its charter and translation of Registrant’s name into English)

The Kingdom of Denmark

(Jurisdiction of incorporation or organization)

Tuborg Boulevard 512

DK-2900 Hellerup, Denmark

(Address of principal executive offices)

Jan Møller Mikkelsen

President and Chief Executive Officer

Tuborg Boulevard 512

DK-2900 Hellerup, Denmark

Telephone: +45 70 22 22 44

Fax: +45 36 94 40 10

(Name, Telephone,E-mail and/or Facsimile number and Address of Company Contact Person)

Securities registered or to be registered pursuant to Section 12(b) of the Act:

Securities registered or to be registered pursuant to Section 12(g) of the Act:None

Securities for which there is a reporting obligation pursuant to Section 15(d) of the Act:None

Indicate the number of outstanding shares of each of the issuer’s classes of capital or common stock as of the close of the period covered by the annual report:

36,984,29242,135,448 ordinary shares

(as of December 31, 2017)2018)

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    ☒  Yes    ☐  No

If this report is an annual or transition report, indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934.    ☐  Yes    ☒  No

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    ☒  Yes    ☐  No

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of RegulationS-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    ☒  Yes    ☐  No

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, anon-accelerated filer, or an emerging growth company. See definition of “large accelerated filer,” “accelerated filer,” and “emerging growth company” in Rule12b-2 of the Exchange Act. (Check one):

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised accounting standards provided pursuant to section 13(a) of the Exchange Act.  ☐

Indicate by check mark which basis of accounting the registrant has used to prepare the financial statements included in this filing:

If “Other” has been checked in response to the previous question, indicate by check mark which financial statement item the registrant has elected to follow:    ☐  Item 17    ☐  Item 18

If this is an annual report, indicate by check mark whether the registrant is a shell company (as defined inRule 12b-2 of the Exchange Act).    ☐  Yes    ☒  No

TABLE OF CONTENTS

i

General

As used herein, references to “we”, “us”, the “company”, “Ascendis”, or “Ascendis Pharma”, or similar terms in this Annual Report on Form20-F shall mean Ascendis Pharma A/S and, as the context requires, its subsidiaries.

Our consolidated financial statements are presented in euros except where otherwise indicated, and are prepared in accordance with International Financial Reporting Standards (“IFRS”) as issued by the International Accounting Standards Board (“IASB”). All references in this annual report to “Dollars” and “$” are to USU.S. Dollars, and all references to “euro” or “€” are to European Union euro. Throughout this annual report, references to ADSs mean ADSs or ordinary shares represented by ADSs, as the case may be.

Special Note Regarding Forward-Looking Statements

This annual report contains forward-looking statements concerning our business, operations and financial performance and condition, as well as our plans, objectives and expectations for our business operations and financial performance and condition. Any statements contained herein that are not statements of historical facts may be deemed to be forward-looking statements. In some cases, you can identify forward-looking statements by terminology such as “aim,” “anticipate,” “assume,” “believe,” “contemplate,” “continue,” “could,” “due,” “estimate,” “expect,” “goal,” “intend,” “may,” “objective,” “plan,” “predict,” “potential,” “positioned,” “seek,” “should,” “target,” “will,” “would,” and other similar expressions that are predictions or indicate future events and future trends, or the negative of these terms or other comparable terminology. These forward-looking statements include, but are not limited to, statements about:

These forward-looking statements are based on senior management’s current expectations, estimates, forecasts and projections about our business and the industry in which we operate and involve known and unknown risks, uncertainties and other factors that are in some cases beyond our control. As a result, any or all of our forward-looking statements in this annual report may turn out to be inaccurate. Factors that may cause actual results to differ materially from current expectations include, among other things, those listed under the section of this annual report titled “Item 3.D—Risk Factors” and elsewhere in this annual report. You are urged to consider these factors carefully in evaluating the forward-looking statements. These forward-looking statements speak only as of the date of this annual report. Except as required by law, we assume no obligation to update or revise these forward-looking statements for any reason, even if new information becomes available in the future. Given these risks and uncertainties, you are cautioned not to rely on such forward-looking statements as predictions of future events.

You should read this annual report and the documents that we reference in this annual report and have filed as exhibits to this annual report completely and with the understanding that our actual future results may be materially different from what we expect. You should also review the factors and risks we describe in the reports we will file or submit from time to time with the SEC after the date of this annual report. We qualify all of our forward-looking statements by these cautionary statements.

PART I

Item 1Identity of Directors, Senior Management and Advisers

Not applicable.

Item 2Offer Statistics and Expected Timetable

Not applicable.

Item 3 Key Information

The selected consolidated financial data as of December 31, 20172018 and 20162017 and for each of the years ended December 31, 2018, 2017 2016 and 20152016 have been derived from our audited consolidated financial statements and notes thereto set forth in Item 18 of this annual report. The selected consolidated financial data for the years ended December 31, 20142015 and 20132014 are derived from the audited consolidated financial statements not appearing in this annual report.

The following selected consolidated financial data should be read in conjunction with our “Operating and Financial Review and Prospects” and our consolidated financial statements and related notes appearing elsewhere in this annual report. Our financial statements are prepared in accordance with IFRS.

The total number of ordinary shares outstanding as of December 31, 2018, 2017, 2016, 2015 and 2014 and 2013 was 42,135,448, 36,984,292, 32,421,121, 25,128,242 16,935,780 and 10,801,948,16,935,780, respectively. The registered share capital as of December 31, 2018, 2017, 2016, 2015 and 2014 and 2013 was DKK 42,135,448, DKK 36,984,292, DKK 32,421,121, DKK 25,128,242 DKK 4,233,945 and DKK 2,700,487,4,233,945, respectively.

Selected Consolidated Statement of Financial Position Data:

The following table sets forth selected consolidated statement of financial position data as of the dates indicated:

Selected Consolidated Cash Flow Statement Data:

The following table sets forth selected consolidated cash flow statement data for the periods indicated:

Exchange Rate Information

Our business is primarily conducted in the European Union, and we maintain our books and records in euros. We have presented results of operations in euros. In this annual report, financial figures included in or extracted from our consolidated financial statements have been translated in accordance with the guidelines under IFRS. For convenience of the reader, this annual report also includes other translations from euros to U.S. dollars and U.S. dollars to euros. Unless specified as of a specific date, or otherwise indicated, translations from euros to U.S. dollars and from U.S. dollars to euros were made at a rate of €0.834€0.873 to $1.00, the official exchange rate quoted by the European Central Bank at the close of business on December 31, 2017. As of March 23, 2018, the official exchange rate of euros to U.S. dollars was €0.810 to $1.00.2018. Such U.S. dollar amounts are not necessarily indicative of the actual amounts of U.S. dollars which could have been actually purchased on exchange of euroeuros on the dates indicated. The rates set forth below are provided solely for your convenience and may differ from the actual rates used in the preparation of our consolidated financial statements and other financial data included in this annual report.

The following table presents information on the exchange rates between the euro and the U.S. dollar for the periods indicated:

Not applicable.

Not applicable.

Our business faces significant risks. You should carefully consider all of the information set forth in this annual report and in our other filings with the United States Securities and Exchange Commission (“SEC”), including the following risk factors which we face and which are faced by our industry. Our business, financial condition or results of operations could be materially adversely affected by any of these risks. This report also contains forward-looking statements that involve risks and uncertainties. Our results could materially differ from those anticipated in these forward-looking statements, as a result of certain factors including the risks described below and elsewhere in this report and our other SEC filings. See “Special Note Regarding Forward-Looking Statements” above.

Risks Related to Our Limited Operating History, Financial Condition and Capital Requirements

We have a limited operating history, no products approved for commercial sale and we may incur significant losses in the future, which makes it difficult to assess our future viability.

We are a biopharmaceutical company applying our innovative TransCon technology^™ technologies to build a leading, fully integrated rare disease company.biopharmaceutical company and to develop a pipeline of product candidates with potentialbest-in-class profiles to address unmet medical needs. Biopharmaceutical product development is a highly speculative undertaking and involves a substantial degree of risk. To date, we have focused substantially all of our efforts on our research and development activities and, in particular, developing our lead product candidates, TransCon Growth Hormone, or TransCon GH,hGH, TransCon Parathyroid Hormone, or TransCon PTH, TransConC-Type Natriuretic Peptide, or TransCon CNP, and our proprietary TransCon technology.technologies. We have only a limited operating history upon which our shareholders and ADS holders can evaluate our business and prospects. Our revenue has been

primarily generated through collaboration agreements under which we have receivedup-front technology licensing fees, payments for the sale of certain intellectual property rights and payments we receive for services rendered to our collaboration partners and other biopharmaceutical companies. Revenue generated from existing or new collaborations may fluctuate significantly over time. Accordingly, going forward, we may incur significant losses from our operations. We had a net loss of €130.1 million during the year ended December 31, 2018 and a net loss of €123.9 million during the year ended December 31, 2017 and a net loss of €68.5 million during the year ended December 31, 2016.2017. Our total equity was €280.1 million as of December 31, 2018 compared to €187.2 million as of December 31, 2017 compared to €176.6 million as of December 31, 2016.2017. Neither the net loss nor net profit we have experienced in prior years are necessarily indicative of our future results.

None of our product candidates have been approved for commercial sale by the U.S. Food and Drug Administration, or FDA, the European Medicines Agency, or EMA, or similarnon-U.S. regulatory authorities, and we have not generated revenues from the sale of approved products. We expect that our annual operating expenses may increase over the next several years as we expand our research and development efforts and operate as a public company.prepare for commercialization. Even if we receive milestone payments from our current or future collaboration partners, we may incur substantial operating losses for the foreseeable future as we execute our operating plan. Additionally, we cannot be certain that we will receive any potential milestones under our agreements with our collaboration partners. For a discussion of the risks associated with our preclinical and clinical development programs with, and potential for milestone and other payments from, our collaboration partners, see “—Risks Related to Our Business.”

Even if we receive milestone payments or royalty payments from our current or future collaboration partners, we may not be able to achieve or sustain profitability. For example, our receipt of milestone payments orup-front payments from our current and potential collaboration partners may not result in the recognition of revenue in the period received, as we may be required to defer the revenue recognition of such payments over time, and depending upon such requirements and the period of recognition, we may still incur losses even after the receipt of such payments. Therefore, we expect that we may incur significant losses in the future. Possible future losses would have an adverse effect on our shareholders’ equity. Further, the net losses or net income we incur may fluctuate significantly from quarter to quarter and year to year, such that aperiod-to-period comparison of our results of operations may not be a reliable indication of our future performance.

We have never generated any revenue from product sales.

We have no products approved for sale and have never generated any revenue from product sales. Our ability to generate revenue from product sales depends on our ability and the ability of our current and future collaboration partners to successfully complete the research and development of our product candidates and obtain the regulatory and marketing approvals necessary to commercialize one or more of our product candidates. We do not anticipate generating revenue from product sales or our royalty rights forin the foreseeable future.near term. Our ability to generate future revenue from product sales or pursuant to milestone payments or royalties from current and future collaboration partners depends heavily on many factors, including but not limited to:

In cases where we, or our current or future collaboration partners, are successful in obtaining regulatory approvals to market one or more of our product candidates, our revenue will be dependent, in part, upon the size of the markets in the territories for which regulatory approval is granted, the accepted price for the product, the availability of competing products, the ability to get reimbursement for our products at any price and the extent of our royalty rights for that territory. If the number of patients suitable for our product candidates is not as significant as we estimate, the indication approved by regulatory authorities is narrower than we expect or the reasonably accepted population for treatment is narrowed by competition, physician choice, treatment guidelines or third-party payor restrictions, we may not generate significant revenue from the sale of such products, even if approved. Our failure to generate revenue from product sales or pursuant toup-front or milestone payments and royalties from current and future collaboration partners would likely depress our market value and could impair our ability to raise capital, expand our business, discover or develop other product candidates or continue our operations.

We may require substantial additional financing to achieve our goals, and a failure to obtain this necessary capital when needed on acceptable terms, or at all, could force us to delay, limit, scale back or cease our product development or any other or all operations.

Since our inception, most of our resources have been dedicated to our research and development activities and, in particular, developing our proprietary TransCon technologytechnologies and our most advanced product candidates. We have funded our operations primarily through issuance of our preference shares, ordinary shares and convertible debt securities and payments to us under our collaboration agreements. For example, in February 2018,March 2019, we received $242.5$539.8 million (€196.8 million)476.9 million in net proceeds from a public offering of American Depositary Shares (representing our ordinary shares) after deducting the underwriting commissioncommissions and estimated offering expenses. As of December 31, 2017,2018, we had cash and cash equivalents of €195.4€277.9 million. We believe that we will continue to expend substantial resources for the foreseeable future, including costs associated with research and development, conducting preclinical studies, clinical trials, obtaining regulatory approvals and, eventually, sales and marketing if any of our product candidates is approved. Because the outcome of any clinical trial and/or regulatory approval process is highly uncertain, we cannot reasonably estimate the actual amounts of additional financing necessary to successfully complete the development, regulatory approval process and commercialization orco-promotion of any of our product candidates.

Based on our current operating plan, we believe that our existing cash and cash equivalents as of December 31, 20172018 will be sufficient to meet our projected cash requirements for at least the 12 months from the date of this annual report. However, our operating plan may change as a result of many factors currently unknown to us, and we may need to seek additional funds sooner than planned. Our future funding requirements will depend on many factors, including, but not limited to:

Additional funds may not be available when we need them on terms that are acceptable to us, or at all. If adequate funds are not available to us on a timely basis, we may be required to delay, limit, scale back or cease our research and development activities, preclinical studies and clinical trials for our product candidates for which we retain such responsibility and our establishment and maintenance of sales and marketing capabilities or other activities that may be necessary to commercialize our product candidates.

Raising additional capital may cause dilution to our holders of shares or ADSs, restrict our operations or require us to relinquish rights to our product candidates on unfavorable terms to us.

We may seek additional capital through a variety of means, including through public or private equity, debt financings or other sources, includingup-front payments and milestone payments from strategic collaborations. To the extent that we raise additional capital through the sale of equity or convertible debt or equity securities, the ownership interest of our shareholders and ADS holders would be diluted, and the terms

may include liquidation or other preferences that adversely affect the rights of our shareholders and ADS holders. Such financing may result in dilution to holders of shares or ADSs, imposition of debt covenants and repayment obligations, or other restrictions that may affect our business. If we raise additional funds throughup-front payments or milestone payments pursuant to strategic partnerships with third parties, we may have to relinquish valuable rights to our product candidates, or grant licenses on terms that are not favorable to us. In addition, we may seek additional capital due to favorable market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans.

Risks Related to Our Business

We are substantially dependent on the success of our most advanced product candidates, which may not be successful in nonclinical studies or clinical trials, receive regulatory approval or be successfully commercialized.

To date, we have invested a significant amount of our efforts and financial resources in the research and development of our current most advanced product candidates utilizing our proprietary TransCon technology.technologies. In particular, we initiatedcompleted a pivotal Phasephase 3 trial for TransCon GHhGH in pediatric growth hormone deficiency, or GHD, patients in August 2016,March 2019, and in 2017, we initiated a long-term extension trial of TransCon GHhGH and a switch trial of TransCon GHhGH for those already taking daily growth hormone therapy.therapy, for which we completed enrollment in September 2018. We submitted a regulatory filing in Australia in the second quarter of 2017 forcompleted a combined Phasephase 1 single and multiple ascending dose study of TransCon PTH for hypoparathyroidism in healthy subjects which is ongoing.in May 2018 and we initiated the phase 2 trial of TransCon PTH in patients with hypoparathyroidism in the first quarter of 2019 to evaluate different dosing regimens. We also submittedreported preliminary results from a regulatory filingphase 1 clinical trial in Australia forhealthy subjects of TransCon CNP in November 2018 and we plan to initiate a phase 2 trial of TransCon CNP in pediatric subjects with achondroplasia in the fourththird quarter of 2017 to conduct a Phase 1 study in healthy subjects to establish the tolerable dose range.2019. Our near-term prospects, including our ability to finance our operations through the receipt of milestone payments and potentialup-front licensing payments and generate revenue from product sales, will depend heavily on our successful development and commercialization of our most advanced product candidates, if approved. The clinical and commercial success of our most advanced product candidates and our TransCon technologytechnologies will depend on a number of factors, including the following:

Before obtaining marketing approval from regulatory authorities for the sale of our product candidates, we, or our current or future collaboration partners, must conduct extensive clinical studies to demonstrate the safety and efficacy of the product candidates in humans. Clinical testing is expensive and can take many years to complete, and its outcome is inherently uncertain. Failure can occur at any time during the clinical trial process; the results of preclinical and clinical studies of our product candidates may not be predictive of the results of later-stage clinical trials. For example, the positive results generated to date in preclinical and clinical studies for TransCon GH do not ensure that the ongoing Phase 3 clinical trials, or other clinical trials, will demonstrate similar results. Product candidates in later stages of clinical trials may fail to show the desired safety and efficacy despite having progressed through preclinical studies and initial clinical trials. A number of companies in the pharmaceutical, biopharmaceutical and biotechnology industries have suffered significant setbacks in advanced clinical trials due to lack of efficacy or adverse safety profiles, notwithstanding promising results in earlier studies, and we cannot be certain that we will not face similar setbacks. Even if our clinical trials are completed, the results may not be sufficient to obtain regulatory approval for our product candidates.

We may experience delays or setbacks in our ongoing Phase 3 trials for TransCon GH, our ongoing Phase 1 trial for TransCon PTH and our Phase 1 trial with TransCon CNP or otherclinical trials, and we do not know whether future clinical trials will begin on time, need to be redesigned, enroll an adequate number of patients on time or be completed on schedule, if at all. Clinical trials can be delayed or terminated for a variety of reasons, including delay or failure to:

Further, we are conducting Phasephase 3 pediatric studies of TransCon GHhGH across clinical sites located in North America, Europe, the Middle East, North Africa, and Oceania (Australia/New Zealand). Conducting clinical trials in foreign countries presents additional risks that may delay completion of clinical trials. These risks include the failure of physicians or enrolled patients in foreign countries to adhere to clinical protocol as a result of differences in healthcare services or cultural customs, managing additional administrative burdens associated with foreign regulatory schemes, as well as political and economic risks relevant to such foreign countries. In addition, the EMA or the FDA may determine that the clinical trial results obtained in foreign subjects do not represent the safety and efficacy of a product candidate when administered in EEA or U.S. patients, and are thus not supportive of an application for a marketing authorization in the EEA or of ana New Drug Application, or NDA, or Biologics License Application, or BLA, approval in the United States. As a result, the EMA or the FDA may not accept data from clinical trials conducted outside the EEA or the United States, respectively, and may require that we conduct additional clinical trials or obtain additional data before we can proceed with filingsubmit an NDA or BLA in the United States or a marketing authorization application in the EEA. The EMA or the FDA may even require conducting additional clinical trials in the EEA or the United States, respectively.

If there are delays in the completion of, or termination of, any clinical trial of our product candidates or if we are required to conduct additional clinical trials in addition to those we have currently planned, the commercial prospects of our product candidates may be harmed, and our ability to generate revenue from product sales from any of these product candidates will be delayed. In addition, any delays in completing the clinical trials will increase costs, slow down our product candidate development and approval process and jeopardize the ability to commence product sales and generate revenue from product sales. Any of these occurrences may significantly harm our business, financial condition and prospects. Clinical trial delays may also allow our competitors to bring products to market before we do, which could impair our ability to obtain orphan exclusivity for our products that potentially qualify for orphan drug designation. In addition, many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of our product candidates.

We depend on collaboration partners to develop and conduct clinical studies with, obtain regulatory approvals for, and manufacture, market and sell our collaboration product candidates, and if such collaboration partners fail to perform as expected, or are unable to obtain the required regulatory approvals for such product candidates, the potential for us to generate future revenue from such product candidates would be significantly reduced and our business would be significantly harmed.

We rely on our collaboration partners to conduct clinical studies of our collaboration product candidates. We have existing collaborations with Sanofi and Genentech. Under these collaborations, we granted Sanofi and Genentech worldwide licenses to develop certain collaboration product candidates in the fields of diabetes (TransCon peptides) and ophthalmology (TransCon anti-VEGF), respectively. Additionally, in connection with the formation of VISEN Pharmaceuticals, or Visen, we granted Visen exclusive rights to develop and commercialize our rare disease endocrinology products based on our proprietary TransCon technologies, including TransCon hGH, TransCon PTH and TransCon CNP, in the People’s Republic of China, including Hong Kong, Macau, and Taiwan, or Greater China, for use in all human indications, subject to certain exceptions. We may also enter into collaboration agreements with other parties in the future relating to our other product candidates. Under our existing collaboration agreements, our collaboration partners are responsible for completing all preclinical and clinical development and obtaining and maintaining regulatory approval for the applicable product candidates from the EMA, the FDA, the National Medical Product Administrations of the People’s Republic of China, or NMPA, and similar regulatory authorities. Ultimately, if such product candidates are advanced through clinical trials and receive marketing approval from the EMA, the FDA, the NMPA or similar regulatory authorities, such collaboration partners will be responsible for commercialization of these collaboration products. The potential for us to obtain future development milestone payments and, ultimately, generate revenue from royalties on sales of such collaboration products depends entirely on successful development, regulatory approval, marketing and commercialization by our collaboration partners.

If our collaboration partners do not perform in the manner we expect or fulfill their responsibilities in a timely manner, or at all, if our agreements with them terminate or if the quality or accuracy of the clinical data they obtain is compromised, the clinical development, regulatory approval and commercialization efforts related to our collaboration product candidates could be delayed or terminated and it could become necessary for us to assume the responsibility at our own expense for the clinical development of such product candidates. In that event, we would likely be required to limit the size and scope of efforts for the development and commercialization of such product candidate, to seek additional financing to fund further development, or to identify alternative strategic collaboration partners, and our potential to generate future revenue from royalties and milestone payments from such product candidate would be significantly reduced or delayed and our business would be harmed. For example, in September 2012, we entered into a collaboration agreement with United Therapeutics for the development and commercialization of TransCon treprostinil and United Therapeutics filed an IND for TransCon treprostinil that was accepted by the FDA in June 2014. In October 2014, we and United Therapeutics terminated the collaboration agreement, and United Therapeutics has transferred the IND for TransCon treprostinil to us. The IND for TransCon treprostinil has since been withdrawn.

Our existing collaborations and any future collaboration arrangements that we may enter into with third parties may not be scientifically or commercially successful. In addition to the risks inherent in the development of a drug product candidate, factors that may affect the success of our collaborations include the following:

In addition, the collaboration agreements provide our collaboration partners with rights to terminate such agreements and licenses under various conditions, which if exercised would adversely affect our product development efforts, make it difficult for us to attract new partners and adversely affect our reputation in the business and financial communities. Our collaboration partners have the right to terminate their respective collaboration agreements with us, upon advance written notice, in the event of our uncured material breach of the agreement and for convenience. In addition, Sanofi may terminate its agreement with us in the event we initiatenon-infringement, invalidity or unenforceability proceedings with respect to Sanofi patents. Genentech and Visen may also terminate in the event of our bankruptcy or insolvency, orand Genentech may additionally terminate if we undergo a change of control in favor of a competitor of Genentech and that competitor does not segregate our company’s personnel and activities under the agreement.

In addition, certain provisions in our exclusive license agreement with Genentech may discourage certain takeover or acquisition attempts, including, as noted above, that in the event we undergo a change of control in favor of a competitor of Genentech and that competitor does not segregate our company’s personnel and activities under the license agreement, Genentech may terminate the license agreement.

The timing and amount of any milestone and royalty payments we may receive under our agreements with our collaboration partners will depend on, among other things, the efforts, allocation of resources, and successful development and commercialization of our product candidates by our collaboration partners. We cannot be certain that any of the development and regulatory milestones will be achieved or that we will receive any future milestone payments under these agreements. In addition, in certain circumstances we may believe that we have achieved a particular milestone and the applicable collaboration partner may disagree with our belief. In that case, receipt of that milestone payment may be delayed or may never be received, which may require us to adjust our operating plans.

We may form additional strategic collaborations in the future with respect to our proprietary programs, but we may not realize the benefits of such collaborations.

We may form strategic collaborations, create joint ventures or enter into licensing arrangements with third parties with respect to our independent programs that we believe will complement or augment our existing business. We have historically engaged, and intend to continue to engage, in partnering discussions with a range of biopharmaceutical companies and could enter into new collaborations at any time. For example, in November 2018, we announced the formation of Visen, a company established to develop, manufacture, and commercialize our endocrinology rare disease therapies in Greater China. In connection with the formation of Visen, we granted Visen exclusive rights to develop and commercialize our rare disease endocrinology products based on our proprietary TransCon technologies, including TransCon hGH, TransCon PTH and TransCon CNP, in Greater China for use in all human indications, subject to certain exceptions. We face significant competition in seeking appropriate strategic partners, and the negotiation process to secure appropriate terms is time-consuming and complex. Any delays in identifying suitable development partners and entering into agreements to develop our product candidates could also delay the commercialization of our product candidates, which may reduce their competitiveness even if they reach the market. Moreover, we may

not be successful in our efforts to establish such a strategic partnership for any future product candidates and programs on terms that are acceptable to us, or at all. This may be for a number of reasons, including thatreasons. For example, under our collaboration with Visen, Visen has a right of first negotiation to develop certain of our endocrinology products in Greater China, so our ability to negotiate such a collaboration with suitable third parties may be hampered by such rights we granted to Visen. Additionally, our product candidates and programs may be deemed to be at too early of a stage of development for collaborative effort, our research and development pipeline may be viewed as insufficient, and/or third parties may not view our product candidates and programs as having sufficient potential for commercialization, including the likelihood of an adequate safety and efficacy profile. Even if we are successful in entering into a strategic alliance or license arrangement, there is no guarantee that the collaboration will be successful, or that any future collaboration partner will commit sufficient resources to the development, regulatory approval, and commercialization of our product candidates, or that such alliances will result in us achieving revenues that justify such transactions.

Our product candidates, other than TransCon GH,hGH, TransCon PTH and TransCon CNP, are in various stages of preclinical development and we may not be successful in our efforts to successfully develop these products or expand our pipeline of product candidates.

A key element of our strategy is to expand our pipeline of product candidates utilizing our proprietary TransCon technology,technologies, and to advance such product candidates through clinical development, either on our own or in conjunction with strategic collaboration partners. Our other product candidates, are in preclinical development and may require significant time and additional research and development before we can file IND or equivalent with regulatory authorities to begin clinical studies. Of the large number of drugs in development, only a small percentage of such drugs successfully complete the EMA or FDA regulatory approval process and are commercialized. Accordingly, even if we are able to continue to fund such development programs, our product candidates may not be advanced to clinical studies or be successfully developed or commercialized. In addition, our preclinical product candidates may not demonstrate the advantages we expect from application of our TransCon technologytechnologies in preclinical studies. In such event, we may decide not to progress any such product candidates into clinical trials.

Research programs to identify product candidates require substantial technical, financial and human resources, whether or not any product candidates are ultimately identified. Although our research and development efforts to date have resulted in several development programs, we may not be able to develop product candidates that are safe and effective. Our research programs may initially show promise in identifying potential product candidates, yet fail to yield product candidates for clinical development or commercialization for many reasons, including the following:

Even if we are successful in continuing to expand our pipeline, through our own research and development efforts or by pursuingin-licensing or acquisition of product candidates, the potential product candidates that we identify or acquire may not be suitable for clinical development, including as a result of being shown to have harmful side effects or other characteristics that indicate that they are unlikely to receive marketing approval and achieve market acceptance. If we do not successfully develop and commercialize a product pipeline, we may not be able to generate revenue from product sales in future periods or achieve or sustain profitability.

Interim and/or preliminary data from our clinical trials that we have announced, or that we may announce or publish from time to time, may change as more patient data become available and are subject to audit and verification procedures that could result in material changes in the final data.

From time to time, we may publish interim or preliminary data from our clinical studies. For example, in JanuaryNovember 2018, we announced initialpreliminary data from the single ascending dose cohorts in our ongoing Phasephase 1, double-blind, randomized, placebo-controlled trial of TransCon PTH.CNP. Interim data for the trials we may complete are subject to the risk that one or more of clinical outcomes may materially change as patient enrollment continues and/or more patient data become available. Preliminary data would also remain subject to audit and verification procedures that may result in the final data being materially different from the preliminary data we previously published. As a result, any interim and preliminary data should be viewed with caution until the final data are available. Material adverse changes in the final data could significantly harm our business prospects.

We may expend our limited resources to pursue a particular product candidate or indication and fail to capitalize on product candidates or indications that may be more profitable or for which there is a greater likelihood of success.

Because we have limited financial and managerial resources, we have focused on research programs and product candidates that utilize our proprietary TransCon technology.technologies. As a result, we may forego or delay pursuit of opportunities with other product candidates or for other indications that later prove to have greater commercial potential. Our resource allocation decisions may cause us to fail to capitalize on viable commercial products or profitable market opportunities. Our spending on current and future research and development programs and product candidates for specific indications may not yield any commercially viable products. If we do not accurately evaluate the commercial potential or target market for a particular product candidate, we may relinquish valuable rights to that product candidate through collaboration, licensing or other royalty arrangements in cases in which it would have been more advantageous for us to retain sole development and commercialization rights to such product candidate.

We rely on third parties to conduct our nonclinical studies and clinical trials. If these third parties do not successfully carry out their contractual duties or meet expected deadlines, we may be unable to obtain regulatory approval for, or commercialize, our product candidates.

We do not currently have the ability to independently conduct clinical trials or nonclinical studies. We rely on medical institutions, clinical investigators, contract laboratories, collaboration partners and other third parties, such as CROs, to conduct clinical trials of our product candidates. The third parties with whom we contract for execution of our clinical trials play a significant role in the conduct of these trials and the subsequent collection and analysis of data. However, these third parties are not our employees, and except for contractual duties and obligations, we control only certain aspects of their activities and have limited ability to control the amount or timing of resources that they devote to our programs. Although we rely on these third parties to conduct our nonclinical studies and our clinical trials, we remain responsible for ensuring that each of our nonclinical studies and clinical trials is conducted in accordance with the applicable protocol, legal, regulatory and scientific standards and our reliance on third parties does not relieve us of our regulatory responsibilities. We and these third parties are required to comply with current good laboratory practices, or GLPs, for nonclinical studies, and good clinical practices, or GCPs, for clinical studies. GLPs and GCPs are regulations and guidelines enforced by the Competent Authorities of the Member States of the European Economic Area, or

EEA, the FDA and comparable foreign regulatory authorities for all of our products in nonclinical and clinical development, respectively. Regulatory authorities enforce GCPs through periodic inspections of trial sponsors, principal investigators and trial sites. If we or any of our third party contractors fail to comply with applicable regulatory requirements, including GCPs, the clinical data generated in our clinical trials may be deemed unreliable and the EMA, the FDA, or similar regulatory authorities may require us to perform additional clinical trials before approving our marketing applications. We cannot be certain that upon inspection by a given regulatory authority, such regulatory authority will determine that any of our clinical trials comply with GCP regulations. In addition, our clinical trials must be conducted with products produced under cGMP regulations. The failure of our contract manufacturers to comply with these regulations may require us to repeat clinical trials, which would delay the regulatory approval process.

Even if our product candidates obtain regulatory approval, they may never achieve market acceptance or commercial success, which will depend, in part, upon the degree of acceptance among physicians, patients, patient advocacy groups, third-party payors and the medical community.

Even if our product candidates obtain EMA, FDA or other regulatory approvals, and are ultimately commercialized, our product candidates may not achieve market acceptance among physicians, patients, third-party payors, patient advocacy groups and the medical community. The degree of market acceptance, if any, for our most advanced product candidates for which marketing approval is obtained will depend on a number of factors, including:

If our product candidates that obtain regulatory approval do not achieve significant market acceptance or commercial success, this could harm our business, results of operations and prospects, and the value of our shares or ADSs.

Our product candidates may cause undesirable side effects or have other properties that could delay or prevent their regulatory approval, limit the commercial profile of an approved label, or result in significant negative consequences following regulatory approval, if any. If any of our product candidates receives marketing approval and subsequently causes undesirable side effects, the ability to market the product candidates could be compromised.

Undesirable side effects caused by TransCon GH,hGH, TransCon PTH, TransCon CNP, or our other product candidates could cause us or regulatory authorities to interrupt, delay or halt clinical trials and could result in a more restrictive label or the delay or denial of regulatory approval by the EMA, the FDA or similar authorities. In the event that trials conducted by us or our collaboration partners, or trials we conduct with our unlicensed product candidates, reveal a high and unacceptable severity and prevalence of side effects, such trials could be suspended or terminated and the EMA, the FDA or similar regulatory authorities could order our collaboration partners or us to cease further development of or deny approval of our product candidates for any or all targeted indications. The drug-related side effects could affect patient recruitment or the ability of enrolled patients to complete the trial or result in potential product liability claims. Any of these occurrences may harm our business, financial condition and prospects significantly.

Additionally, if we successfully develop a product candidate and it receives marketing approval, the FDA could require us to adopt a Risk Evaluation and Mitigation Strategy, or REMS, to ensure that the benefits of treatment with such product candidate outweigh the risks for each potential patient, which may include, among other things, a communication plan to health care practitioners, patient education, extensive patient monitoring or distribution systems and processes that are highly controlled, restrictive and more costly than what is typical for the industry.

In addition, in the event that any of our product candidates receives regulatory approval and we or others later identify undesirable side effects caused by one of our products, a number of potentially significant negative consequences could occur, including:

Competition in the biotechnology and pharmaceutical industries is intense and our competitors may discover, develop or commercialize products faster or more successfully than us. If we are unable to compete effectively our business, results of operations and prospects will suffer.

The markets in which we intend to compete are undergoing, and are expected to continue to undergo, rapid and significant technological changes. Some of our product candidates are for fields in which competitive products already exist and are established. We expect competition to intensify as technological advances are made or new drugs and biotechnology products are introduced. New developments by competitors may render our current or future product candidates and/or technologiesnon-competitive, obsolete or not economical. Our competitors’ products may be more efficacious or marketed and sold more effectively than any of our product candidates.

We are aware of several pharmaceutical and biopharmaceutical companies that have commenced clinical studies of products or have successfully commercialized products addressing areas that we are targeting. For example, several companies are developing sustained release or long-acting products for the treatment of growth hormone deficiency, including Bioton S.A., Critical Pharmaceuticals, Ltd.,Dong-A Pharmaceutical, GeneScience Pharmaceuticals Co., Ltd., Genexine Inc., JCR Pharmaceuticals Co., Ltd., Novo Nordisk A/S, and OPKO Health, Inc. (in collaboration with Pfizer Inc.). Shire plc owns the rights to Natpara, a treatment for hypoparathroidism.hypoparathyroidism. In addition, we are aware of several academic groups and companies working on making longer-acting agonists of the PTH receptor, or PTH1R. Other companies and groups are developing or commercializing therapies for hypoparathyroidism, including Shire, Chugai Pharmaceutical Co., Ltd., Entera Bio, Extend Biosciences, Massachusetts General Hospital, Alizé Pharma and Eli Lilly and Company. Other companies are developing therapies for achondroplasia, including BioMarin, Therachon, QED Therapeutics and Therachon.BioClin Therapeutics. BioMarin Pharmaceuticals, Inc. is developing vosoritide for the treatment of achondroplasia, Therachon and BioClin Therapeutics, Inc. are developing compounds for achondroplasia. In addition to product-based competition, our TransCon technology facestechnologies face technology-based competition as we believe other companies are developing or evaluating enhanced drug delivery and sustained release technologies. In particular, we believe Nektar Therapeutics, OPKO Health, Inc., ProLynx LLC and Serina Therapeutics, Inc. are developing technologies that use reversible linkers and that may be competitive with our TransCon technology.technologies.

It is also possible that our competitors will commercialize competing drugs or treatments before we or our collaboration partners can launch any products developed from our product candidates. We also anticipate that we will face increased competition in the future as new companies enter into our target markets.

Furthermore, to the extent we are developing TransCon product candidates that incorporate already approved drugs, we face competition from the pharmaceutical companies which are currently marketing such approved products. These pharmaceutical companies can generally be expected to seek to delay the introduction of competing products through a variety of means including:

Many of our competitors have:

If we successfully develop and obtain approval for our product candidates, we will face competition based on many different factors, including:

In addition, academic institutions, government agencies, and other public and private organizations conducting research may seek patent protection with respect to potentially competitive products or technologies. These organizations may also establish exclusive collaborative or licensing relationships with our competitors.

Our competitors may develop or commercialize products with significant advantages in regard to any of these factors. Our competitors may therefore be more successful in commercializing their products than we are, which could adversely affect our business, results of operations and prospects, and the value of our shares or ADSs.

For additional information regarding the competitive landscape for our product candidates, see “Item 4 B. Information on the Company – Business Overview – TransCon Product Candidates.”

Our proprietary TransCon technology istechnologies include a new approach to extending the residence time and duration of action of a variety of drug products and may not result in any products of commercial value.

Our TransCon technology hastechnologies have been developed to improve the delivery of a variety of drug products. However, we cannot be certain that our TransCon technologytechnologies will be deemed safe or efficacious, nor that any aspects of our TransCon technologytechnologies will yield additional product candidates that could enter clinical development and, ultimately, be commercially valuable. Further, one of our two carrier systems, the TransCon hydrogel carrier system, has never been used in humans. As a result, our TransCon hydrogel carriers, when dosed in humans, may fail to perform as we expect. Failure of any of our product candidates to be successfully developed and approved may result in our TransCon technologytechnologies being viewed as an ineffective approach to developing drug products which would harm our business and prospects.

We apply our TransCon technologytechnologies to both approved and unapproved parent drugs to extend the life of such drugs in the body, and to enhance the overall benefit of a given therapy. Even when applied to approved parent drugs, we have generated limited clinical data on our product candidates using our systemic TransCon technologytechnologies with respect to safety and efficacy for long-term treatment in humans. The long-term safety and efficacy of our TransCon technologytechnologies and the extended life in the body of our product candidates utilizing TransCon technologytechnologies compared to currently approved products is unknown, and it is possible that our product candidates may have an increased risk of unforeseen reactions following extended treatment relative to other currently approved products. If extended treatment with product candidates utilizing TransCon in our ongoing or future clinical trials results in any concerns about the safety or efficacy of our TransCon technology,technologies, we may be unable to successfully develop or commercialize our product candidates.

Product candidates created utilizing the TransCon prodrug technologytechnologies are new chemical entities that employ novel technologies that have not yet been approved by the FDA, EMA or other regulatory authorities. These regulatory authorities have limited experience in evaluating our technologies and product candidates.

Our TransCon prodrug technology allowstechnologies allow for the creation of new molecular entities through the transient conjugation of parent drug molecules to our soluble and microparticle TransCon carrier molecules via our TransCon linkers. We and our collaboration partners are developing product candidates based on these novel technologies, and we intend to work closely with our collaboration partners to understand and deliver the requisite demonstration of safety and efficacy that the FDA, the EMA and other regulatory authorities may seek for the approval of product candidates that incorporate the TransCon technology.technologies. It is possible that the regulatory approval process may take significant time and resources and require deliverables from independent third parties not under our control. For some of our product candidates, the regulatory approval path and requirements may not be clear, which could add significant delay and expense. Delays or failure to obtain regulatory approval of any of the products that we or our collaboration partners develop using our novel technologies would adversely affect our business.

We have limited clinical data on product candidates utilizing the TransCon technology platformplatforms to indicate whether they are safe or effective for long-term use in humans.

Our product candidates transiently link a parent drug molecule to select TransCon carriers via our TransCon linkers. Once injected, we believe that our prodrugs predictably release the unmodified parent drug molecule over time, thus preserving the parent drug’s original mode of action, and, we believe, the parent drug’s original safety and efficacy profile. We believe that our TransCon carriers remain bound to our TransCon linkers and that they are cleared from the body predominantly by renal filtration and biliary transport with fecal excretion. We have limited clinical data on product candidates utilizing the systemic TransCon technologytechnologies to indicate whether they are safe or effective for long-term use in humans, including the safety of any degradation products that may result after the TransCon carrier and TransCon linker are cleaved from the parent drug molecule. As an example, our TransCon prodrugs utilize polyethylene glycol, or PEG, and hydrogels incorporatingPEG-based polymers as TransCon carriers. Although the safety and efficacy of PEG and permanently PEGylated proteins has been demonstrated within their respective indications by the approval of drugs such as PegIntron^®, PegaSys^®, Neulasta^®, Somavert^®, Cimzia^®, Krystexxa^®, Adynovate^® and Rebinyn^® and we are not aware of any evidence forPEG-related safety issues with PEGylated proteins in the clinic, health authorities, including the EMA, have historically posed general questions relating to the distribution, elimination, and the potential for PEG accumulation to pharmaceutical companies involved in the development of PEGylated drug products. If treatment with any of our product candidates in our clinical trials results in concerns about their safety or efficacy, we and our collaboration partners may be unable to successfully develop or commercialize any or all of our TransCon technologytechnologies based product candidates or enter into collaborations with respect to our product candidates.

We have limited clinical data on TransCon GHPTH and TransCon PTHCNP and no clinical data on our other preclinical product candidates, to indicate whether they are safe or effective for long-term use in humans.

We have generated clinical data on six months of dosing with TransCon GH, and limited clinical data on TransCon PTH and no clinical data on our other product candidates, including TransCon CNP, that utilize the TransCon technology to extend their duration of action.CNP. It is unknown whether long-term repeated administration of TransCon GH, TransCon PTH or TransCon CNP could result in issues that may adversely affect safety. If extended treatment with TransCon GH, TransCon PTH, TransCon CNP, or any of our other preclinical product candidates, in our clinical trials, results in any safety or efficacy concerns, we may be unable to successfully develop or commercialize our product candidates or enter into collaborations with respect to our product candidates.

We may seek orphan drug designation for some of our product candidates and we may be unsuccessful, or may be unable to maintain the benefits associated with orphan drug designation, including the potential for market exclusivity, for product candidates for which we obtain orphan drug designation.

Regulatory authorities in some jurisdictions, including the United States, may designate drugs or biologics intended to treat relatively small patient populations as orphan drug products. Under the U.S. Orphan Drug Act, the FDA may designate a drug or biologic as an orphan drug if it is intended to treat a rare disease or condition, which is generally defined as a patient population of fewer than 200,000 individuals in the United States, or a patient population greater than 200,000 in the United States where there is no reasonable expectation that the cost of developing the drug will be recovered from sales in the United States.

If a drug or biologic with an orphan drug designation subsequently receives the first marketing approval for the indication for which it has such designation, the drug or biologic is entitled to a period of marketing exclusivity, which precludes the FDA from approving another marketing application for the same drug and indication for that time period, except in limited circumstances. If our competitors are able to obtain orphan drug exclusivity prior to us, for products that constitute the “same drug” and treat the same indications as our product candidates, we may not be able to have competing products approved by the applicable regulatory authority for a significant period of time. The applicable period is seven years in the United States.

As part of our business strategy, we intend to pursue orphan drug designation for certain of our product candidates. For example, in June 2018 we were granted orphan drug designation by the FDA for TransCon PTH and in February 2019 we were granted orphan drug designation by the FDA for TransCon CNP. However, we may be unsuccessful in obtaining orphan drug designation for other product candidates, and may be unable to maintain the benefits associated with orphan drug designation. Even if we obtain orphan drug exclusivity for any of our product candidates, that exclusivity may not effectively protect those product candidates from competition because different drugs can be approved for the same condition, and orphan drug exclusivity does not prevent the FDA from approving the same or a different drug in another indication. Even after an orphan drug is approved, the FDA can subsequently approve a later application for the same drug for the same condition if the FDA concludes that the later drug is clinically superior in that it is shown to be safer in a substantial portion of the target populations, more effective or makes a major contribution to patient care. In addition, a designated orphan drug may not receive orphan drug exclusivity if it is approved for a use that is broader than the indication for which it received orphan designation. Moreover, orphan-drug-exclusive marketing rights in the United States may be lost if the FDA later determines that the request for designation was materially defective or if we are unable to manufacture sufficient quantities of the product to meet the needs of patients with the rare disease or condition. Orphan drug designation neither shortens the development time or regulatory review time of a drug nor gives the drug any advantage in the regulatory review or approval process.

Any product candidates for which we intend to seek approval as biologic products may face competition sooner than anticipated.

The Affordable Care Act includes a subtitle called the Biologics Price Competition and Innovation Act of 2009, or BPCIA, which created an abbreviated approval pathway for biological products that are biosimilar to or interchangeable with anFDA-licensed reference biological product. Under the BPCIA, an application for a biosimilar product may not be submitted to the FDA until four years following the date that the reference product was first licensed by the FDA. In addition, the approval of a biosimilar product may not be made effective by the FDA until twelve years from the date on which the reference product was first licensed. During this twelve-year period of exclusivity, another company may still market a competing version of the reference product if the FDA

approves a full BLA for the competing product containing the sponsor’s own preclinical data and data from adequate and well-controlled clinical trials to demonstrate the safety, purity and potency of its product. The law is complex and is still being interpreted and implemented by the FDA. As a result, its ultimate impact, implementation and meaning are subject to uncertainty, and any processes adopted by the FDA to implement the BPCIA could have a material adverse effect on the future commercial prospects for our biological products.

We believe that any of our future product candidates approved as a biological product under a BLA should qualify for the twelve-year period of exclusivity. However, there is a risk that this exclusivity could be shortened due to Congressional action or otherwise, or that the FDA will not consider our product candidates to be reference products for competing products, potentially creating the opportunity for generic competition sooner than anticipated. Other aspects of the BPCIA, some of which may impact the BPCIA exclusivity provisions, have also been the subject of recent litigation. Moreover, the extent to which a biosimilar, once approved, could be substituted for any one of our reference products in a way that is similar to traditional generic substitution fornon-biological products will depend on a number of marketplace and regulatory factors that are still developing.

We lack direct sales and marketing capabilities, and are wholly dependent on collaboration partners for the commercialization of our product candidates. If we are unable to establish sales capabilities on our own or through third parties, we may not be able to commercialize any of our product candidates.

We have no direct sales marketing or distribution capabilities. We have entered into collaboration agreements with third parties to market and sell product candidates in the fields of diabetes (unspecified TransCon Peptides) and ophthalmology (TransCon anti-VEGF). Currently,Except for our license agreements with Visen for Greater China, we have no sales, marketing or distribution agreements for TransCon GH,hGH, TransCon PTH, TransCon CNP, or our other product candidates. We may enter into arrangements with third parties to market and sell certain of our other product candidates.candidates in one or multiple geographies. We may not be able to enter into such marketing and sales arrangements with others on acceptable terms, if at all. To the extent that we enter into marketing and sales arrangements with other companies, our revenues, if any, will depend on the terms of any such arrangements and the efforts of others. These efforts may turn out not to be sufficient.

We currently do not have our own sales organization. To commercialize any of our product candidates, we or our collaboration partners must build and/or maintain marketing, sales, distribution, managerial and othernon-technical capabilities or make arrangements with third parties to perform these services, and we or our collaboration partners may not be successful in doing so. If one or more of our product candidates receives regulatory approval, we may establish a specialty sales organization with technical expertise and supporting distribution capabilities toco-promote and/or commercialize our product candidates, which will be expensive and time consuming. As a company, we have no prior experience in the marketing, sale and distribution of pharmaceutical products and there are significant risks involved in building and managing a sales organization, including our ability to hire, retain, and incentivize qualified individuals, generate sufficient sales leads, provide adequate training to sales and marketing personnel, comply with regulatory requirements applicable to the marketing and sale of drug products and effectively manage a geographically dispersed sales and marketing team. Any failure or delay in the development of our internal sales, marketing and distribution capabilities with respect to anon-licensed product candidate would adversely impact the commercialization of such product candidate.

We may choose to work with third parties that have direct sales forces and established distribution systems, either to augment our own sales force and distribution systems or in lieu of our own sales force and distribution systems. If we are unable to enter into such arrangements on acceptable terms or at all, we may not be able to successfully commercialize our product candidates.

We rely on third parties to manufacture our preclinical and clinical drug supplies, and we intend to rely on third parties to produce commercial supplies of any approved product candidate and device.

We have limited personnel with experience in manufacturing, and we do not own facilities for manufacturing our products and product candidates for the potential pivotal clinical studies and/or commercial manufacturing of our products and product candidates. We depend on our collaboration partners and other third parties to manufacture and provide analytical services with respect to our most advanced product candidates and device.

In addition, if our product candidates are approved, to produce the quantities necessary to meet anticipated market demand, we and/or our collaboration partners will need to secure sufficient manufacturing capacity with third-party manufacturers. If we and/or our collaboration partners are unable to produce our product candidates in sufficient quantities to meet the requirements for the launch of the product or to meet future demand, our revenues and gross margins could be adversely affected. To be successful, our product candidates must be manufactured in commercial quantities in compliance with regulatory requirements and at acceptable costs. We and/or our collaboration partners will regularly need to secure access to facilities to manufacture some of our product candidates commercially. All of this will require additional funds and inspection and approval by the Competent Authorities of the Member States of the EEA, the FDA and other regulatory authorities. If we and/or our collaboration partners are unable to establish and maintain a manufacturing capacity within our planned time and cost parameters, the development and sales of our products and product candidates as well as our business, results of operations and prospects, and the value of our shares or ADSs could be adversely affected.

We and/or our collaboration partners may encounter problems with aspects of manufacturing our collaboration products and product candidates, including the following:

products to Visen. In turn, we currently rely on third party manufacturers in fulfilling our supply obligations to Visen. For additional information regarding the risks of our dependence on our collaboration partners, see the risk factors above “—We are substantially dependent on the success of our most advanced product candidates, which may not be successful in nonclinical studies or clinical trials, receive regulatory approval or be successfully commercialized” and “—We depend on collaboration partners to develop and conduct clinical studies with, obtain regulatory approvals for, and manufacture, market and sell our collaboration product candidates, and if such collaboration partners fail to perform as expected, or are unable to obtain the required regulatory approvals for such product candidates, the potential for us to generate future revenue from such product candidates would be significantly reduced and our business would be significantly harmed.”

If our contract manufacturers cannot successfully manufacture material that conforms to our specifications and the strict regulatory requirements of the FDA or similar regulatory authorities, they will not be able to secure and/or maintain regulatory approval for their manufacturing facilities. In addition, we have no control over the ability of our contract manufacturers to maintain adequate quality control, quality assurance and qualified personnel. If the FDA, the Competent Authorities of the Member States of the EEA, or a similar regulatory authority does not approve these facilities for the manufacture of our product candidates or if it withdraws any such approval in the future, we may need to find alternative manufacturing facilities, which would significantly impact our ability to develop, obtain regulatory approval for or market our product candidates, if approved.

We rely on our manufacturers to purchase from third-party suppliers the materials necessary to produce our product candidates for our clinical studies. Any significant delay or discontinuation in the supply of such materials would delay completion of our clinical studies or clinical studies conducted by our collaboration partners who rely on us for supply, and harm our business.

There are a limited number of suppliers for raw materials that we use to manufacture our drugs, and there may be a need to identify alternate suppliers to prevent a possible disruption of the manufacture of the materials necessary to produce our product candidates for our clinical studies, and, if approved, ultimately for commercial sale. We do not have any control over the process or timing of the acquisition of these raw materials by our manufacturers. Although we generally do not begin a clinical study unless we believe we have on hand, or will be able to manufacture, a sufficient supply of a product candidate to complete such study, and we currently envision that Visen, who relies on us for clinical supply of our product candidates, would do the same, any significant delay or discontinuity in the supply of a product candidate, or the raw material components thereof, for a clinical study due to the need to replace a third-party manufacturer could considerably delay completion of our or Visen’s clinical studies, product testing, and potential regulatory approval of our product candidates, which could harm our business and results of operations.

Any inability to obtain suppliers, including an inability to obtain, or delay in obtaining, approval of a supplier from the Competent Authorities of the Member States of the EMA, the FDA or other regulatory authorities, would delay or prevent the clinical development and commercialization of our product candidates, and could impact our ability to meet supply obligations to collaboration partners for the development of, or future marketing and sale, of our product candidates.

If product liability lawsuits are brought against us, we may incur substantial liabilities and may be required to limit commercialization of our product candidates.

Our business exposes us to potential product liability risks which are inherent in research and development, preclinical and clinical studies, manufacturing, marketing and use of our product candidates. For example, we may be sued if any product we develop allegedly causes injury or is found to be otherwise unsuitable during product testing, manufacturing, marketing or sale. Any such product liability claims may include allegations of defects in manufacturing, defects in design, a failure to warn of dangers inherent in the product, negligence, strict liability, and a breach of warranties. Claims could also be asserted under state consumer protection acts. Product liability claims may be expensive to defend and may result in judgments against us which are potentially punitive. If we cannot successfully defend ourselves against product liability claims, we may incur substantial liabilities or be required to limit commercialization of our product candidates. Even successful defense would require significant financial and management resources. Regardless of the merits or eventual outcome, liability claims may result in:

It is generally necessary for us to secure certain levels of insurance as a condition for the conduct of clinical studies. We believe that our product liability insurance for clinical studies is sufficient to cover claims. We currently maintain liability insurance with certain specified coverage limits. We cannot be certain that the insurance policies will be sufficient to cover all claims that may be made against us. Our inability to obtain and maintain sufficient product liability insurance at an acceptable cost and scope of coverage to protect against potential product liability claims could prevent or inhibit the commercialization of any products we develop. We currently carry product liability insurance covering use in our clinical trials in the amount of $8$20 million in the aggregate.aggregate on our primary insurance policy and $20 million in the aggregate on our excess insurance policy. Any claim that may be brought against us could result in a court judgment or settlement in an amount that is not covered, in whole or in part, by our insurance or that is in excess of the limits of our insurance coverage. Our insurance policies also have various, limits, exclusions and deductibles, and given these various limits, exclusions and deductibles, we may be subject to a product liability claim for which we have no coverage. We will have to pay any amounts awarded by a court or negotiated in a settlement that exceed our coverage limitations or that are not covered by our insurance, and we may not have, or be able to obtain, sufficient capital to pay such amounts. Moreover, in the future, we may not be able to maintain insurance coverage at a reasonable cost or in sufficient amounts to protect us against losses. Product liability insurance is expensive, difficult to obtain and may not be available in the future on acceptable terms.

We will need to significantly increase the size of our organization and we may have difficulties in managing our growth and expanding our operations successfully.

As of December 31, 2017,2018, we had 137216 full-time employees worldwide, with key facilities in Denmark, Germany, and the United States. As we and/or our collaboration partners advance our product candidates through the development and commercialization process, we will need to expand managerial, operational, financial and other resources to manage our operations, preclinical and clinical trials, research and development activities, regulatory filings, manufacturing and supply activities, and any marketing and commercialization activities or contract with other organizations to provide these capabilities for us. As operations expand, we expect that we will need to manage additional relationships with various collaboration partners, suppliers and other organizations. Our ability to manage our operations and growth requires us to continue to improve our operational, financial and management controls, reporting systems and procedures across a global organization. Such growth could place a strain on our administrative and operational infrastructure. We may not be able to make improvements to our management information and control systems in an efficient or timely manner and may discover deficiencies in existing systems and controls. Our management, personnel, systems and facilities currently in place may not be adequate to support this future growth. Our need to effectively execute our growth strategy requires that we either internally, together with our collaboration partners or through third party contractors, as applicable:

If we are not able to attract, retain and motivate necessary personnel to accomplish our business objectives, we may experience constraints that will significantly impede the achievement of our development objectives, our ability to raise additional capital and our ability to implement our business strategy.

We incur significant costs as a result of operating as a public company, and our management devotes substantial time to compliance initiatives. We may fail to comply with the rules that apply to public companies, including Section 404 of the Sarbanes-Oxley Act of 2002, which could result in sanctions or other penalties that would harm our business.

We incur significant legal, accounting and other expenses as a public company, including costs resulting from public company reporting obligations under the Securities Exchange Act of 1934, as amended, or the Exchange Act, and regulations regarding corporate governance practices. Our senior management and other personnel need to devote a substantial amount of time to ensure that we maintain compliance with all of these requirements. Moreover, the reporting requirements, rules and regulations increase our legal and financial compliance costs and make some activities more time consuming and costly. Any changes we make to comply with these obligations may not be sufficient to allow us to satisfy our obligations as a public company on a timely basis, or at all. These reporting requirements, rules and regulations, coupled with the increase in potential litigation exposure associated with being a public company, could also make it more difficult for us to attract and retain qualified persons to serve on our board of directors or board committees or to serve as members of our senior management, or to obtain certain types of insurance, including directors’ and officers’ insurance, on acceptable terms.

We are subject to Section 404 of The Sarbanes-Oxley Act of 2002, or Section 404, and the related rules of the Securities and Exchange Commission, or SEC, which generally require our senior management and independent registered public accounting firm to report on the effectiveness of our internal control over financial reporting. Beginning with the year ended December 31, 2015, Section 404 required an annual management assessment of the effectiveness of our internal control over financial reporting. However, for so long as we remain an emerging growth company as defined in the Jumpstart Our Business Startups Act of 2012, or JOBS Act, we intend to take advantage of certain exemptions from various reporting, requirements that are applicable to public companies that are not emerging growth companies, including, but not limited to, not being required to complyand beginning with the auditor attestation requirements of Section 404. Onceyear ended December 31, 2018, we are no longer an emerging growth company or, if prior to such date, we opt to no longer take advantage of the applicable exemption, we will be required to include an opinion from our independent registered public accounting firm on the effectiveness of our internal controls over financial reporting. We will remain an emerging growth company until the earlier of (1) the last day of the fiscal year following the fifth anniversary of the completion of our IPO, (2) the last day of the fiscal year in which we have total annual gross revenue of at least $1.07 billion, or (3) the last day of the fiscal year in which we are deemed to be a large accelerated filer, which means the market value of the ADS and our ordinary shares that is held bynon-affiliates exceeds $700 million as of the prior June 30th, and (4) the date on which we have issued more than an aggregate of $1.0 billion innon-convertible debt during the prior three-year period.

As we grow our business and enter into new activities, and as the reporting requirements increase, we may identify deficiencies and be unable to remediate them before we must provide the required reports. Furthermore, if we have a material weakness in our internal controls over financial reporting, as we did as of December 31, 2015, we may not detect errors on a timely basis and our consolidated financial statements may be materially misstated. We may not be able to conclude on an ongoing basis that we have effective internal control over financial reporting, which could harm our operating results, cause investors to lose confidence in our reported financial information and cause the trading price of the ADSs to fall. In addition, as a public company we are required to file accurate and timely annual reports with the SEC under the Exchange Act. Any failure to report our financial results on an accurate and timely basis could result in sanctions, lawsuits, delisting of the ADSs from The NASDAQthe Nasdaq Global Select Market or other adverse consequences that would harm our business.

Our operating results may vary significantly from period to period and these variations may be difficult to predict.

Our potential future revenues and operating results are expected to vary significantly from period to period due to a number of factors. Many of these factors are outside of our control. These factors include:

Our revenues in any particular period may be lower than we anticipate and, if we are unable to reduce spending in that period, our operating results will be harmed.

We may engage in strategic transactions that could impact our liquidity, increase our expenses and present significant distractions to our management.

We may consider strategic transactions, such as acquisitions of companies, asset purchases, andin-licensing orout-licensing of products, product candidates or technologies. Additional potential transactions that we may consider include a variety of different business arrangements, including spin-offs, strategic partnerships, joint ventures, restructurings, divestitures, business combinations and investments. Any such transaction may require us to incurnon-recurring or other charges, may increase our near- and long-term expenditures and may pose significant integration challenges or disrupt our senior management or business, which could adversely affect our operations and financial results. For example, these transactions may entail numerous operational and financial risks, including:

Accordingly, although we cannot be certain that we will undertake or successfully complete any transactions of the nature described above, any transactions that we do complete may be subject to the foregoing or other risks, and could harm our business, results of operations, financial condition and prospects.

Exchange rate fluctuations or abandonment of the euro currency may harm our results of operations and financial condition.

Due to the international scope of our operations, fluctuations in exchange rates, particularly between the euro, the Danish krone and the U.S. dollar, may adversely affect us. Although we are based in Denmark, we source research and development, manufacturing, consulting and other services from several countries. In addition, our arrangements with our collaboration partners are denominated in euros and U.S. dollars. Further, potential future revenue may be derived from abroad, including from the United States. We currently attempt to limit our exposure to exchange rate risks by maintaining cash positions in the currencies in which we expect to incur the majority of our future expenses; however, for a variety of reasons we may be unable to maintain cash positions in the currencies in which we expect to incur the majority of our future expenses and we may fail to predict the currency of our future expenses, accurately or at all. As a result, our business and the price of the ADSs may be affected by fluctuations in foreign exchange rates between the euro and these other currencies, which may also have a significant impact on our reported results of operations and cash flows from period to period. We currently do not enter into foreign exchange contracts to cover our exposure to exchange rate fluctuations, or any other form of exchange rate hedging arrangements. If we fail to manage foreign exchange risk adequately our business, results of operations and prospects, and the value of our shares or ADSs may be adversely affected.

In addition, the possible abandonment of the euro by one or more members of the European Union could harm our business in the future. Despite measures taken by the European Union to provide funding to certain E.U. member states in financial difficulties and by a number of European countries to stabilize their economies and reduce their debt burdens, it is possible that the euro could be abandoned in the future as a currency by countries that have adopted its use. This could lead to there-introduction of individual currencies in one or more E.U. member states. The effects on our business of a potential dissolution of the European Union, the exit of one or more E.U. member states from the European Union or the abandonment of the euro as a currency, are impossible to predict with certainty, and any such events could harm our business, financial condition and results of operations.

The results of the United Kingdom’s referendum onpending withdrawal from the European Union may have a negative effect on global economic conditions, financial markets and our business.

In June 2016, a majority of voters in the United Kingdom elected to withdraw from the European Union in a national referendum.referendum, which is generally referred to as Brexit. In March 2017, the United Kingdom delivered notice under Article 50 of the Lisbon Treaty of its intent to leave the European Union. The referendum was advisory,United Kingdom is currently scheduled to leave the European Union on April 12, 2019, unless this date is extended. To date there

has been no agreement between the European Union and the United Kingdom on the terms of any withdrawal are subject to a negotiation period that could last at least two years after the governmentexit. Brexit, the subsequent high-profile failures of the United Kingdom formally initiates ato agree on an exit strategy, and the pending withdrawal process. Nevertheless,of the referendum has created significantUnited Kingdom, may lead to legal uncertainty about the future relationshipand potentially divergent laws and regulations between the United Kingdom and the European Union, including with respect to the laws and regulations that will apply as the United Kingdom determines which EU laws to replicate or replace and this uncertainty may persist for years. As a result of Brexit, other European countries may seek to conduct referenda with respect to their continuing membership with the European Union. Given these possibilities and others we may not anticipate, as well as the absence of comparable precedent, it is unclear what financial, regulatory and legal implications the withdrawal of the United Kingdom from the European Union lawswould have and how such withdrawal would affect us, and the full extent to replace or replicate in the event of a withdrawal. The referendum has also given rise to calls for the governments of other European Union member states to consider withdrawal. which our business could be adversely affected.

These developments, or the perception that any of them could occur, have had and may continue to have a material adverse effect on global economic conditions and the stability of global financial markets, and may significantly reduce global market liquidity and restrict the ability of key market participants to operate in certain financial markets. Any of these factors could depress economic activity and restrict our access to capital, which could have a material adverse effect on our business, financial condition and results of operations and reduce the price of the ADSs.

Risks associated with our international operations, including seeking and obtaining approval to commercialize our product candidates in foreign jurisdictions, could harm our business.

We engage extensively in international operations, which include seeking marketing approval for certain of our product candidates in foreign jurisdictions. We expect that we are or will be subject to additional risks related to entering into these international business markets and relationships, including:

The manufacture of our TransCon product candidates is dependent upon third party manufacturers that are based in other parts of the world, including Europe and Japan. This manufacturing process requires that the components used in our product candidates are transported long distances, through multiple countries, which increases the risk that issues in the global supply chain or other disruptions to the international marketplace could harm our business.

The parent drug, drug substance, drug product and other components of our product candidates are currently acquired from single-source suppliers. The loss of these suppliers, or their failure to supply could materially and adversely affect our business.

Our growth hormone parent drug as well as our TransCon GHhGH drug substance are supplied by Fujifilm Diosynth Biotechnologies UK Limited, or Fujifilm, pursuant to our agreement with Fujifilm. TransCon GHhGH drug product in vials is mademanufactured by Rentschler Biopharma SE,Fill Solutions GmbH, or Rentschler, pursuant to our agreement with Rentschler. TransCon GHhGH drug product in dual chamber cartridges will be supplied by Vetter Pharma Fertigung for use in our drug delivery device made by Philips Medisize A/S (formerly Medicom Innovation Partner A/S.S). The intermediates of our proprietary TransCon linkers are made by CARBOGEN AMCIS AG under an agreement with CARBOGEN AMCIS AG and accompanying purchase orders. For products that utilize soluble TransCon carriers, NOF Corporation (Japan), or NOF, supplies PEGs. Furthermore, NOF is responsible for coupling the TransCon linker used for TransCon GHhGH to mPEG under manufacturing agreements and accompanying purchase orders. Our PTH as well as our TransCon PTH drug substance is supplied by Bachem, Switzerland, pursuant to our agreement with Bachem. TransCon PTH drug product in vials is mademanufactured by Baccinex, SA, Switzerland in collaboration with Bachem. We expect Vetter Pharma Fertigung to manufacture TransCon PTH drug product in cartridges and assemble the cartridges with a drug delivery device made by Ypsomed AG. Intermediate for TransCon CNP is supplied by Corden Pharma, Switzerland and CNP drug substance is supplied by Wacker Biotech, Germany. Our TransCon CNP drug product in vials is manufactured by Rentschler pursuant to our agreement with Rentschler. We do not currently have any other suppliers for the drug substance, drug product or other components of our product candidates for TransCon GHhGH, TransCon PTH and TransCon PTH and,CNP, although we believe that there are alternate sources of supply that could satisfy our clinical and commercial requirements, we cannot provide assurance that identifying alternate sources and establishing relationships with such sources would not result in significant delays in the development of our product candidates. Additionally, we may not be able to enter into supply arrangements with alternative suppliers on commercially reasonable terms or at all. A delay in the development of our product candidates or having to enter into a new agreement with a different third party on less favorable terms than we have with our current suppliers could have a material adverse impact upon on our business.

We may not be successful in our efforts to identify additional product candidates based on our TransCon technology.technologies.

An important element of our strategy is to develop new products and product candidates based on our TransCon technology.technologies. Research programs to identify new product candidates require substantial technical, financial and human resources. These research programs may initially show promise in identifying potential product candidates, yet fail to yield product candidates for clinical development for a number of reasons, including that:

If we are unable to develop suitable product candidates through internal research programs or otherwise, we will not be able to increase our revenues in future periods, which could harm our business, results of operations and prospects, and the value of our shares or ADSs.

We are highly dependent on the services of our President and Chief Executive Officer, Jan Møller Mikkelsen, and our Chief Scientific Officer, Dr. Harald Rau, and if we are not able to retain these membersthis member of our senior management or recruit additional management, clinical and scientific personnel, our business will suffer.

Our success depends in part on our continued ability to attract, retain and motivate highly qualified personnel. We may not be able to attract or retain qualified management and scientific and clinical personnel in the future due to the intense competition for qualified personnel among biotechnology, pharmaceutical and other businesses. Our industry has experienced a high rate of turnover of management personnel in recent years. If we are not able to attract, retain and motivate necessary personnel to accomplish our business objectives, we may experience constraints that will significantly impede the achievement of our development objectives, our ability to raise additional capital and our ability to implement our business strategy.

In particular, we are highly dependent upon Jan Møller Mikkelsen, our President and Chief Executive Officer, and Dr. Harald Rau, our Chief Scientific Officer. The loss of services of either of these individualsthis individual could delay or prevent the successful development of our product pipeline, completion of our planned clinical trials or the commercialization of our product candidates.

We may have difficulties in attracting and retaining key personnel, and if we fail to do so our business may suffer.

We are highly dependent on the principal members of our senior management and scientific staff, the loss of whose services could adversely affect the achievement of planned development objectives. Although we have not historically experienced unique difficulties attracting and retaining qualified employees, we could experience such problems in the future. For example, competition for qualified personnel in the biotechnology and pharmaceuticals field is intense due to the limited number of individuals who possess the skills and experience required by our industry. This is particularly true in Heidelberg, Germany where we operate our research and development activities. As such, we could have difficulty attracting experienced personnel to our company and may be required to expend significant financial resources in our employee recruitment and retention efforts.

For us to further expand our product development plans, we will need to hire additional qualified scientific personnel to perform research and development. We will also need to hire personnel with expertise in clinical testing, government regulation, sales and marketing, and finance, and might need to hire personnel with expertise in manufacturing and marketing.manufacturing. We may not be able to attract and retain personnel on acceptable terms, given the competition for such personnel among biotechnology, pharmaceutical and healthcare companies, universities andnon-profit research institutions. Although we may be successful in attracting and retaining suitably qualified scientific personnel, there can be no assurance that we will be able to attract and retain such personnel on acceptable terms given the competition for experienced scientists from numerous pharmaceutical and chemical companies, specialized biotechnology firms, universities and other research institutions. Our failure to do so could adversely affect our business, results of operations and prospects, and the value of our shares or ADSs.

Our internal computer systems, or those of our CROs or other contractors or consultants, may fail or suffer security breaches, which could result in a material disruption of our product development programs and other critical business functions.

Despite the implementation of security measures, our internal computer systems and those of our CROs and other contractors and consultants are vulnerable to damage from computer viruses, unauthorized access, natural disasters, terrorism, war and telecommunication and electrical failures. While we have not experienced any such system failure, accident or security breach to date, if such an event were to occur and cause interruptions in our operations, it could result in a material disruption of our programs. For example, the loss of clinical trial data from completed or ongoing clinical trials for any of our product candidates could result in delays in our regulatory approval efforts, and the loss of research data could result in delays of our research and development efforts and it would be expensive to recover or reproduce the data. To the extent that any disruption or security breach results in a loss of or damage to our data or applications, or inappropriate disclosure of confidential or proprietary information, we could incur liability and the further development of our product candidates could be delayed.

Risks Related to Government Regulatory and Legal Requirements

The regulatory approval processes of the EMA, the FDA and comparable authorities are lengthy, time consuming, and inherently unpredictable. If we are ultimately unable to obtain regulatory approval for our product candidates, our business will be substantially harmed.

The research, testing, manufacturing, labeling, approval, selling, import, export, marketing and distribution of drug products are subject to extensive regulation by the FDA, E.U. legislative bodies and other regulatory authorities in the United States, the EEA and other jurisdictions, which regulations differ from country to country. Neither we nor any of our collaboration partners is permitted to market any drug product in the United States until we receive marketing approval from the FDA. Equally, neither we nor any of our collaboration partners is permitted to market any drug product in the EEA until we receive a marketing authorization from the EMA or EEA Member State Competent Authorities. We have not submitted an application or obtained marketing approval for any of our product candidates anywhere in the world.

Obtaining regulatory approval of a new drug application, oran NDA or marketing authorization,BLA, can be a lengthy, expensive and uncertain process. In addition, failure to comply with FDA and other applicable U.S., EEA and foreign regulatory requirements may subject us to administrative or judicially imposed sanctions or other actions, including:

The time required to obtain approval by the EMA, the FDA and comparable authorities is unpredictable, typically takes many years following the commencement of clinical studies, and depends upon numerous factors. The EMA, the FDA and comparable authorities have substantial discretion in the approval process and we may encounter matters with the EMA, the FDA or such comparable authorities that requires us to expend additional time and resources and delay or prevent the approval of our product candidates. For example, the FDA or EMA may require us to conduct additional studies or trials for drug or biologic products either prior to or post-approval, such as additional drug-drug interaction studies or safety or efficacy studies or trials, or it may object to elements of our clinical development program such as the number of subjects in our current clinical trials from the United States or Europe. In addition, approval policies, regulations or the type and amount of clinical data necessary to gain approval may change during the course of a product candidate’s clinical development and may vary among jurisdictions, which may cause delays in the approval or result in a decision not to approve an application for regulatory approval. Despite the time and expense exerted, failure can occur at any stage. Applications for our product candidates could fail to receive regulatory approval for many reasons, including but not limited to the following:

This lengthy approval process, as well as the unpredictability of the results of clinical studies, may result in our failure to obtain regulatory approval to market any of our product candidates, which would significantly harm our business, results of operations, and prospects. Additionally, if the EMA, the FDA or comparable foreign regulatory authorities require that we conduct additional clinical studies, place limitations on our label, delay approval to market our product candidates or limit the use of our products, our business and results of operations may be harmed.

In addition, even if we were to obtain approval, regulatory authorities may approve any of our product candidates for fewer or more limited indications than we request, may not approve the price we intend to charge for our products, may grant approval contingent on the performance of costly post-marketing clinical trials, may impose a REMS, or may approve a product candidate with a label that does not include the labeling claims necessary or desirable for the successful commercialization of that product candidate. Any of the foregoing scenarios could harm the commercial prospects for our product candidates.

We do not have and may never obtain the regulatory approvals we need to market our product candidates.

We have not yet received any regulatory approvals required for the commercial sale of TransCon GH,hGH, TransCon PTH, TransCon CNP, or any of our other product candidates in the United States, the EEAEMA or in any other jurisdiction. Furthermore, we have yet to submit an NDA or BLA to the FDA, or a Marketing Authorization Application, or MAA, to the EMA, national regulatory authorities in Europe or to any international regulatory authorities for any of our product candidates. We have only limited experience in filing and pursuing applications necessary to obtain regulatory approval or licensure, and we cannot be certain that any of our product candidates will be approved or licensed for marketing. The process of applying for regulatory approval is expensive, often takes many years and can vary substantially based upon the type, complexity and novelty of the product candidates involved. If any or all of our product candidates are not approved, this could harm our business, results of operations and prospects, and the value of our shares or ADSs.

If we are unable to file an MAA for approval to the EMA for our product candidates, or if we are required to generate additional data related to safety and efficacy, to obtain approval from the FDA for any of our product candidates, we may be unable to meet our anticipated development and commercialization timelines.

While we have an active IND with the FDA for TransCon GH,hGH, and we have completed substantive discussions with the FDA regarding the development of TransCon GHhGH in pediatric growth hormone deficiency, and we believe we are satisfying the necessary criteria, there is no guarantee that FDA requirements will not change between now and the time of our filing in the United States. We have not yet filed an MAA with the EMA for any of our product candidates. Depending on the data that may be required by the EMA for approval, we may be required to conduct substantial new research and development activities beyond those in which we currently plan to engage to obtain approval of our product candidates. Such additional new research and development activities would be costly and time consuming.

We are developing an auto-injector and higher-strength version of TransCon GH to facilitate the administration of the product byend-users and additional time may be required to obtain regulatory approval for our auto-injector or higher-strength version.auto-injector.

We are developing an auto-injector with Phillips Medisize A/S (formerly Medicom Innovation Partner A/SS) to facilitate the administration of TransCon GHhGH by patients. In addition, we are developing a drug delivery device with Ypsomed to facilitate the administration of TransCon PTH by patients. We anticipate the EMA, the FDA and other similar regulatory authorities willmay require a separate approval of our auto-injector and TransCon PTH drug delivery device that is in addition toas part of the approval we are seeking for the drug component of TransCon GHhGH and TransCon PTH. Because of our auto-injector and TransCon PTH drug delivery device, the FDA’s review of TransCon GHhGH and/or TransCon PTH may include the participation of both the FDA’s Center for Drug Evaluation and Research and the FDA’s Center for Devices and Radiological Health, which may complicate or prolong the review, and in the EEA the EMA’s review may require the involvement of an EU Notified Body. As a result, we may experience delays for our auto-injector and TransCon GHhGH and/or our drug delivery device of TransCon PTH and TransCon PTH.

Safety issues with the parent drugs or other components of our product candidates, or with approved products of third parties that are similar to our product candidates, could give rise to delays in the regulatory approval process.

Our product development portfolio consists of prodrugs that are new molecular entities that incorporate existing parent drug molecules, many of which have been previously approved by the EMA, the FDA or other foreign regulatory authorities. Discovery of previously unknown problems with any of the parent drugs that we use in our TransCon product candidates may result in restrictions on its permissible uses, including withdrawal of the product from the market.

Additionally, problems with approved parent drugs marketed by third parties that utilize the same therapeutic target as the parent drug we use in our TransCon product candidates could adversely affect the development of our product candidates.

Any failure or delay in commencing or completing clinical trials or obtaining regulatory approvals for our product candidates would delay commercialization of the product candidates and severely harm our business and financial condition.

We are subject to extensive and costly government regulation. If we fail to obtain or maintain governmental approvals, we will not be able to commercialize our product candidates and our business will suffer.

Pharmaceutical products, including product candidates employing our technology,TransCon technologies, are subject to extensive and rigorous government regulation. The FDA, the EMA and other regulatory authorities regulate the development, testing, manufacture, safety, efficacy, record-keeping,record- keeping, labeling, storage, approval, advertising, promotion, sale and distribution of pharmaceutical products. If products employing our technologyTransCon technologies are marketed in countries outside of the European Union and the United States, they will also be subject to extensive regulation by other governments. The regulatory review and approval or licensing process, including preclinical testing and clinical studies of each product candidate, is lengthy, expensive and uncertain. Securing marketing approval requires the submission of extensive preclinical and clinical data and supporting information to the FDA, EMA and/or EEA Competent Authorities for each indication to establish the candidate’s safety and efficacy. The approval process takes many years, requires substantial resources, involves post-marketing surveillance, and may involve ongoing post-marketing studies. While clinical studies are designed with scientific advice from regulatory authorities, such plans must often be put in place years in advance of application for marketing approval. At the time of such application, the clinical and regulatory environment may have changed significantly as a result of new scientific discoveries, competitor product evaluations, changes in medical health care policies, new technical standards and other factors beyond our control.

Regulators can refuse marketing approval, or can require us or our collaboration partners to repeat previous clinical studies or conduct further clinical studies. Apre-approval inspection of manufacturing facilities by regulatory authorities may need to be completed before marketing approval can be obtained, and such facilities will be subject to periodic inspections that could prevent or delay marketing approval, or require the expenditure of financial or other resources to address. If we or our collaboration partners do not succeed in obtaining regulatory approval, or succeed only after delays, this could have a material effect on our ability to generate revenues. Delays in obtaining regulatory approvals may:

Material changes to an approved product, such as manufacturing changes or additional labeling claims, require further FDA and EMA and/or EEA Competent Authorities review and approval before marketing. Once obtained, any approvals may be withdrawn or revoked because of unforeseen safety, effectiveness or potency concerns or failure to comply with governmental regulations. Further, if we, our collaboration partners or our contract manufacturers fail to comply with applicable FDA, EMA, and/or EEA Competent Authorities regulatory requirements at any stage during the regulatory process, the FDA, EMA, and/or EEA Competent Authorities and other regulatory authorities may impose sanctions, including:

Even if we receive regulatory approval for a product candidate, we will be subject to ongoing regulatory obligations and review, which may result in significant additional expense. Additionally, any product candidates, if approved, could be subject to labeling and other restrictions and we may be subject to penalties if we fail to comply with regulatory requirements or experience unanticipated problems with our products.

The governmental regulation of the development of products and product candidates extends beyond clinical studies to approval required for their sale and monitoring of such products after sale. This regulation, approval and monitoring is the responsibility of numerous authorities in Denmark, the United States, the European Union and authorities in other territories. Following any regulatory approval of a product candidate, we, our collaboration partners and the manufacturers of our products will be subject to continuing regulatory obligations, including safety reporting requirements, regulatory oversight of product promotion and marketing, and cGMP requirements. Furthermore, the manufacturing processes, labeling, packaging, distribution, adverse event reporting, storage, advertising, promotion and recordkeeping for the product will be subject to extensive and ongoing regulatory requirements. These regulations cover all aspects of manufacturing, testing, quality control and record keeping of our products. If we or our collaboration partners or manufacturers fail to comply with applicable regulatory requirements, we may be subject to fines, suspension or withdrawal of regulatory approvals, product recalls, seizure of products, operating restrictions and criminal prosecution. These requirements include submissions of safety and other post-marketing information and reports, registration, as well as continued compliance with cGMPs and GCPs for any clinical trials that we conduct post-approval. As such, we and our third party contract manufacturers will be subject to continual review and periodic inspections to assess compliance with regulatory requirements. Accordingly, we and others with whom we work must continue to expend time, money, and effort in all areas of regulatory compliance, including manufacturing, production, and quality control. Regulatory authorities may also impose significant restrictions on a product’s indicated uses or marketing or impose ongoing requirements for potentially costly post-marketing studies. Furthermore, any new legislation addressing drug safety issues could result in delays or increased costs to assure compliance.

In the United States, advertising and promotional materials must comply with FDA rules in addition to other potentially applicable U.S. laws. In particular, the promotional claims that we would be permitted to make for our products would be limited to those supported by the approved product labeling. In addition, under the Federal Food, Drug, and Cosmetic Act, particular restrictions are placed on the distribution of human growth hormone products, potentially including TransCon hGH. The distribution of product samples to physicians must also comply with the requirements of the Prescription Drug Marketing Act. Manufacturing facilities remain subject to FDA inspection and must continue to adhere to International Conference on Harmonisation

of Technical Requirements for Registration of Pharmaceuticals for Human Use and the FDA’s cGMP requirements. Application holders must obtain FDA approval for product and manufacturing changes, depending on the nature of the change. Sales, marketing, and scientific/educational grant programs must comply with the U.S. Anti-Kickback Statute, the False Claims Act, as amended, the privacy regulations promulgated under the Health Insurance Portability and Accountability Act, or HIPAA, and similar state laws. Pricing and rebate programs must comply with the Medicaid Drug Rebate Program requirements of the Omnibus Budget Reconciliation Act of 1990, as amended, and the Veterans Health Care Act of 1992, as amended. If products are made available to authorized users of the Federal Supply Schedule of the General Services Administration, additional laws and requirements apply. All of these activities are also potentially subject to U.S. consumer protection and unfair competition laws.

We will also be required to report certain adverse reactions and production problems, if any, to the FDA, and to comply with requirements concerning advertising and promotion for our products. Promotional communications with respect to prescription drugspharmaceutical products are subject to a variety of legal and regulatory restrictions and must be consistent with the information in the product’s approved label. As such, we may not promote our products for indications or uses for which they do not have FDA approval.

Later discovery of previously unknown problems with a product, including adverse events of unanticipated severity or frequency, or with our third-party manufacturers or manufacturing processes, or failure to comply with regulatory requirements, may result in, among other things:

Any government investigation of alleged violations of law could require us to expend significant time and resources in response, and could generate negative publicity. Any failure to comply with ongoing regulatory requirements may significantly and adversely affect our ability to commercialize our product candidates. If regulatory sanctions are applied or if regulatory approval is withdrawn, the value of our company and our operating results will be adversely affected.

In addition, the FDA’s policies may change and additional government regulations may be enacted that could prevent, limit or delay regulatory approval of our product candidates. If we are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we are not able to maintain regulatory compliance, we may lose any marketing approval that we may have obtained, which would adversely affect our business, prospects and ability to achieve or sustain profitability.

Within the European Union, once a Marketing Authorization is obtained, numerous post-approval requirements also apply, and as in the United States, theoff-label promotion of medicinal products is not permitted. The requirements are regulated by both E.U. regulations (such as reporting of adverse events) as well as national applicable regulations (related to prices and promotional material).

The regulatory requirements relating to the manufacturing, testing, marketing and sale of pharmaceutical products are subject to periodic change. This may impact our ability and the ability of our collaboration partners to conduct clinical studies in the European Union. Changes in the regulations governing us could increase costs and adversely affect our business.

Furthermore, companies developing pharmaceutical products are facing increased demands to publish clinical trial results. Any such publication by us may, in addition to the additional cost of the publication, lead to investors misinterpreting the published data due to its technical and scientific nature, which, in turn, may adversely affect our business, results of operations and prospects and the value of our shares or ADSs.

Changes in funding for the FDA and other government agencies could hinder their ability to hire and retain key leadership and other personnel, or otherwise prevent new products and services from being developed or commercialized in a timely manner, which could negatively impact our business.

The ability of the FDA to review and approve new products can be affected by a variety of factors, including government budget and funding levels, ability to hire and retain key personnel and accept the payment of user fees, and statutory, regulatory, and policy changes. Average review times at the agency have fluctuated in recent years as a result. In addition, government funding of other government agencies that fund research and development activities is subject to the political process, which is inherently fluid and unpredictable.

Disruptions at the FDA and other agencies may also slow the time necessary for new drugs and biologics to be reviewed and/or approved by necessary government agencies, which would adversely affect our business. For example, over the last several years, including for 35 days beginning on December 22, 2018, the U.S. government has shut down several times and certain regulatory agencies, such as the FDA, have had to furlough critical FDA employees and stop critical activities. If a prolonged government shutdown occurs, it could significantly impact the ability of the FDA to timely review and process our regulatory submissions, which could have a material adverse effect on our business.

Third-party payor coverage and reimbursement status of newly-approved products is uncertain. Failure to obtain or maintain adequate coverage and reimbursement for our product candidates could limit our ability to market those products and decrease our ability to generate revenue.

The availability and adequacy of coverage and reimbursement by governmental healthcare programs such as Medicare and Medicaid, private health insurers and other third-party payors are essential for most patients to be able to afford treatments such as ours, assuming approval. Our ability to achieve acceptable levels of coverage and reimbursement for drug treatments by governmental authorities, private health insurers and other organizations will have an effect on our ability to successfully commercialize, and attract additional collaboration partners to invest in the development of our product candidates. We cannot be sure that coverage and reimbursement in the United States, the European Union or elsewhere will be available for any product that we may develop, and any reimbursement that may become available may be decreased or eliminated in the future. Third-party payors increasingly are challenging prices charged for pharmaceutical products, medical devices and services, and many third-party payors may refuse to provide coverage and reimbursement for particular drugs when an equivalent generic drug is available. It is possible that a third-party payor may consider our product candidate and the generic parent drug as substitutable and only offer to reimburse patients for the generic drug. Even if we show improved efficacy or improved convenience of administration with our product candidate, pricing of the existing parent drug may limit the amount we will be able to charge for our product candidate. If reimbursement is not available or is available only at limited levels, we may not be able to successfully commercialize our product candidates, and may not be able to obtain a satisfactory financial return on products that we may develop.

There is significant uncertainty related to the insurance coverage and reimbursement of newly approved products. In the United States, third-party payors, including private and governmental payors, such as the Medicare and Medicaid programs, play an important role in determining the extent to which new drugs, biologics and medical devices will be covered. The Medicare and Medicaid programs increasingly are used as models for how private payors and other governmental payors develop their coverage and reimbursement policies for drugs, biologics and medical devices. It is difficult to predict at this time what third-party payors will decide with respect to the coverage and reimbursement for our product candidates.

Outside the United States, international operations are generally subject to extensive governmental price controls and other market regulations, and we believe the increasing emphasis on cost-containment initiatives in Europe, Canada, and other countries has and will continue to put pressure on the pricing and usage of our product candidates, if approved, and on related parent drugs. In many countries, the prices of medical products are subject to varying price control mechanisms as part of national health systems. Other countries allow companies to fix their own prices for medical products, but monitor and control company profits. Additional foreign price controls or other changes in pricing regulation could restrict the amount that we are able to charge for our product candidates. Accordingly, in markets outside the United States, the reimbursement for our products may be reduced compared with the United States and may be insufficient to generate commercially reasonable revenue and profits.

Moreover, increasing efforts by governmental and third-party payors in the United States and abroad to cap or reduce healthcare costs may cause such organizations to limit both coverage and the level of reimbursement for new products approved and, as a result, they may not cover or provide adequate payment for our product candidates. We expect to experience pricing pressures in connection with the sale of any of our product candidates due to the trend toward managed healthcare, the increasing influence of health maintenance organizations, and additional legislative changes. The downward pressure on healthcare costs in general, particularly prescription drugs, medical devices and surgical procedures and other treatments, has become very intense. As a result, increasingly high barriers are being erected to the entry of new products.

We and our collaboration partners and contract manufacturers are subject to significant regulation with respect to manufacturing our product candidates. The manufacturing facilities on which we rely may not continue to meet regulatory requirements or may not be able to meet supply demands.

We depend on third parties to manufacture products employing our technology.TransCon technologies. Components of a finished therapeutic product approved for commercial sale or used in late-stage clinical studies must be manufactured in accordance with cGMP. These regulations govern manufacturing processes and procedures (including record keeping) and the implementation and operation of quality systems to control and assure the quality of investigational products and products approved for sale. All entities involved in the preparation of product candidates for clinical studies or commercial sale, including our existing contract manufacturers for our product candidates, are subject to extensive regulation. Manufacturing facilities are subject topre-approval and ongoing periodic inspection by the FDA, EEA Competent Authorities and other corresponding governmental authorities, including unannounced inspections, and must be licensed before they can be used in commercial manufacturing of products employing our technology.TransCon technologies. After regulatory approvals or licensure are obtained, the subsequent discovery of previously unknown manufacturing, quality control or regulatory documentation problems or failure to maintain compliance with the regulatory requirements may result in restrictions on the marketing of a product, revocation of the license, withdrawal of the product from the market, seizures, injunctions, or criminal sanctions. Poor control of production processes can lead to the introduction of contaminants or to inadvertent changes in the properties or stability of our product candidates that may not be detectable in final product testing. We, our collaboration partners, or our contract manufacturers must supply all necessary documentation in support of an NDA, BLA, MAA or comparable regulatory filing on a timely basis and must adhere to cGMP regulations enforced by the FDA, EEA Competent Authorities and other regulatory authorities through their facilities inspection programs. Some of our contract manufacturers have never produced a commercially approved pharmaceutical product and therefore have not obtained the requisite regulatory authority approvals to do so. Although we oversee the contract manufacturers, we cannot control the manufacturing process of, and are completely dependent on, our contract manufacturing partners for compliance with the regulatory requirements. If these facilities do not pass apre-approval plant inspection, regulatory approval of the products may not be granted or may be substantially delayed until any violations are corrected to the satisfaction of the regulatory authority, if ever. In addition, we have no control over the ability of our contract manufacturers to maintain adequate quality control, quality assurance and qualified personnel.

The regulatory authorities also may, at any time following approval of a product for sale, audit the manufacturing facilities of our collaboration partners and third-party contractors. If any such inspection or audit identifies a failure to comply with applicable regulations or if a violation of our product specifications or applicable regulations occurs independent of such an inspection or audit, we or the relevant regulatory authority may require remedial measures that may be costly and/or time consuming for us or a third party to implement, and that may include the temporary or permanent suspension of a clinical study or commercial sales or the temporary or permanent suspension of production or closure of a facility. Any such remedial measures imposed upon us or third parties with whom we contract could harm our business.

If we, our collaboration partners, or any of our third-party manufacturers fail to maintain regulatory compliance, the FDA or other applicable regulatory authority can impose regulatory sanctions including, among other things, refusal to approve a pending application for a new drugpharmaceutical product, withdrawal of an approval, or suspension of production. As a result, our business, financial condition, and results of operations may be harmed.

Additionally, if supply from one approved manufacturer is interrupted, an alternative manufacturer would need to be qualified through an NDA or BLA, a supplemental NDA or BLA, a marketing authorization variation application or equivalent foreign regulatory filing, which could result in further delay. The regulatory authorities may also require additional studies if a new manufacturer is relied upon for commercial production. Switching manufacturers may involve substantial costs and is likely to result in a delay in our desired clinical and commercial timelines.

These factors could cause us to incur higher costs and could cause the delay or termination of clinical studies, regulatory submissions, required approvals, or commercialization of our product candidates. Furthermore, if our suppliers fail to meet contractual requirements and we are unable to secure one or more replacement suppliers capable of production at a substantially equivalent cost, our clinical studies may be delayed or we could lose potential revenue.

Our operations involve hazardous materials and we and third parties with whom we contract must comply with environmental laws and regulations, which can be expensive and restrict how we do business.

As a pharmaceutical company, we are subject to environmental and safety laws and regulations, including those governing the use of hazardous materials. The cost of compliance with health and safety regulations is substantial. Our business activities involve the controlled use of hazardous materials. Our research and development activities involve the controlled storage, use and disposal of hazardous materials, including the components of our product candidates and other hazardous compounds. We and manufacturers and suppliers with whom we may contract are subject to laws and regulations governing the use, manufacture, storage, handling and disposal of these hazardous materials. In some cases, these hazardous materials and various wastes resulting from their use are stored at our and our manufacturers’ facilities pending their use and disposal. We cannot eliminate the risk of accidental contamination or injury from these materials, which could cause an interruption of our commercialization efforts, research and development efforts and business operations, environmental damage resulting in costlyclean-up and liabilities under applicable laws and regulations governing the use, storage, handling and disposal of these materials and specified waste products. We cannot guarantee that the safety procedures utilized by third-party manufacturers and suppliers with whom we may contract will comply with the standards prescribed by laws and regulations or will eliminate the risk of accidental contamination or injury from these materials. In such an event, we may be held liable for any resulting damages and such liability could exceed our resources and European, U.S. federal and state or other applicable authorities may curtail our use of certain materials and/or interrupt our business operations. Furthermore, environmental laws and regulations are complex, change frequently and have tended to become more stringent. We cannot predict the impact of such changes and cannot be certain of our future compliance. We do not currently carry biological or hazardous waste insurance coverage. In the event of an accident or environmental discharge, we may be held liable for any consequential damage and any resulting claims for damages, which may exceed our financial resources and may materially adversely affect our business, results of operations and prospects, and the value of our shares or ADSs.

If we fail to comply or are found to have failed to comply with EEA, FDA and other regulations related to the promotion of our products for unapproved uses, we could be subject to criminal penalties, substantial fines or other sanctions and damage awards.

The regulations relating to the promotion of products for unapproved uses are complex and subject to substantial interpretation by the EEA Competent Authorities, the FDA and other regulatory authorities. If any of our product candidates receives marketing approval, we and any collaboration partner will be restricted from marketing the product outside of its approved labeling, also referred to asoff-label promotion. However, physicians may nevertheless prescribe an approved product to their patients in a manner that is inconsistent with the approved label, which is anoff-label use. We intend to implement compliance and training programs designed to ensure that our sales and marketing practices comply with applicable regulations regardingoff-label promotion. Notwithstanding these programs, the EEA Competent Authorities, the FDA or other government authorities may allege or find that our practices constitute prohibited promotion of our product candidates for unapproved uses. We also cannot be sure that our employees will comply with company policies and applicable regulations regarding the promotion of products for unapproved uses.

Over the past several years, a significant number of pharmaceutical and biotechnology companies have been the target of inquiries and investigations by various U.S. federal and state regulatory, investigative, prosecutorial and administrative entities in connection with the promotion of products for unapproved uses and other sales practices, including the Department of Justice and various U.S. Attorneys’ Offices, the Office of Inspector General of the Department of Health and Human Services, the FDA, the Federal Trade Commission and various state Attorneys General offices. These investigations have alleged violations of various U.S. federal and state laws and regulations, including claims asserting antitrust violations, violations of the Food, Drug and Cosmetic Act, the False Claims Act, the Prescription Drug Marketing Act, anti-kickbackanti- kickback laws, and other alleged violations in connection with the promotion of products for unapproved uses, pricing and Medicare and/or Medicaid reimbursement. Many of these investigations originate as “qui tam” actions under the False Claims Act. Under the False Claims Act, any individual can bring a claim on behalf of the government alleging that a person or entity has presented a false claim, or caused a false claim to be submitted, to the government for payment. The person bringing a qui tam suit is entitled to a share of any recovery or settlement. Qui tam suits, also commonly referred to as “whistleblower suits,” are often brought by current or former employees. In a qui tam suit, the government must decide whether to intervene and prosecute the case. If it declines, the individual may pursue the case alone.

If the FDA or any other governmental agency initiates an enforcement action against us or if we are the subject of a qui tam suit and it is determined that we violated prohibitions relating to the promotion of products for unapproved uses, we could be subject to substantial civil or criminal fines or damage awards and other sanctions such as consent decrees and corporate integrity agreements pursuant to which our activities would be subject to ongoing scrutiny and monitoring to ensure compliance with applicable laws and regulations. Any such fines, awards or other sanctions would have an adverse effect on our revenue, business, financial prospects and reputation.

If approved, our product candidates may cause or contribute to adverse medical events that we are required to report to regulatory authorities and if we fail to do so we could be subject to sanctions that would harm our business.

Some participants in clinical trials of our product candidates have reported adverse events. As with all clinical trials, serious or severe adverse events may occur which may compromise the program. The FDA, EEA, and foreign regulatory authority regulations require that we report certain information about adverse medical events if those products may have caused or contributed to those adverse events, both during their development and after commercialization, if approved. The timing of our obligation to report is triggered by the date we become aware of the adverse event as well as the nature of the event. We may fail to report adverse events we become aware of within the prescribed timeframe. We may also fail to appreciate that we have become aware of a reportable adverse event, especially if it is not reported to us as an adverse event or if it is an adverse event that is unexpected or removed in time from the use of our products. If we fail to comply with our reporting obligations, the FDA, EEA Competent Authorities, or a foreign regulatory authority could take action, including criminal prosecution, the imposition of civil monetary penalties, seizure of our products or delay in approval or clearance of future products.

Our employees, independent contractors, principal investigators, CROs, consultants, vendors and collaboration partners may engage in misconduct or other improper activities, including noncompliance with regulatory standards and requirements.

We are exposed to the risk that our employees, independent contractors, principal investigators, CROs, consultants, vendors and collaboration partners may engage in fraudulent conduct or other illegal activity. Misconduct by these parties could include intentional, reckless and/or negligent conduct or unauthorized activities that violate: (1) FDA regulations, including those laws that require the reporting of true, complete and accurate information to the FDA; (2) manufacturing standards; (3) U.S. federal and state fraud and abuse and other healthcare laws and regulations; or (4) laws that require the reporting of true and accurate financial information and data. Specifically, sales, marketing and business arrangements in the healthcare industry are subject to extensive laws and regulations intended to prevent fraud, kickbacks, self-dealing and other abusive practices. These laws and regulations may restrict or prohibit a wide range of pricing, discounting, marketing and promotion, sales commission, customer incentive programs and other business arrangements. These activities also include the improper use of information obtained in the course of clinical trials, which could result in regulatory sanctions and serious harm to our reputation. It is not always possible to identify and deter misconduct by employees and other third parties, and the precautions we take to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to be in compliance with such laws or regulations. Additionally, we are subject to the risk that a person or government could allege such fraud or other misconduct, even if none occurred. If any such actions are instituted against us, and we are not successful in defending ourselves or asserting our rights, those actions could have a significant impact on our business, including the imposition of significant civil, criminal and administrative penalties, damages, monetary fines, possible exclusion from participation in Medicare, Medicaid and other U.S. federal healthcare programs, individual imprisonment, contractual damages, reputational harm, diminished profits and future earnings, and curtailment of our operations, any of which could adversely affect our ability to operate our business and our results of operations.

Failure to obtain regulatory approvals innon-U.S. jurisdictions would prevent us from marketing our products outside of the United States.

In the EEA, medicinal products can only be commercialized after obtaining a Marketing Authorization, or MA. There are two types of MA:

Under the above described procedures, before granting the MA, the EMA or the Competent Authorities of the Member States of the EEA make an assessment of the risk-benefit balance of the product on the basis of scientific criteria concerning its quality, safety and efficacy.

In the EEA, the EMA’s Committee for Orphan Medicinal Products grants orphan drug designation to promote the development of products that are intended for the diagnosis, prevention or treatment of life-threatening or chronically debilitating conditions affecting not more than five in 10,000 persons in the E.U. Community and for which no satisfactory method of diagnosis, prevention, or treatment has been authorized (or the product would be a significant benefit to those affected). Additionally, designation is granted for products intended for the diagnosis, prevention, or treatment of a life-threatening, seriously debilitating or serious and chronic condition and when, without incentives, it is unlikely that sales of the drug in the European Union would be sufficient to justify the necessary investment in developing the medicinal product. An E.U. orphan drug designation entitles a party to financial incentives such as reduction of fees or fee waivers and 10 years of market exclusivity is granted following medicinal product approval. This period may be reduced to six years if the orphan drug designation criteria are no longer met, including where it is shown that the product is sufficiently profitable not to justify maintenance of market exclusivity. Orphan drug designation must be requested before submitting an application for marketing approval. Orphan drug designation does not convey any advantage in, or shorten the duration of, the regulatory review and approval process. At this time, we do not have an Orphan Medicinal Product Designation for TransCon GH,hGH, or any of our other product candidates.

In the EEA, marketing authorization applications for new medicinal products not authorized have toin the EU will only be regarded as valid, if they include one of the following: (i) the results of all studies conducted in the pediatric population,performed and details of all information collected in compliance with a pediatricpaediatric investigation plan, orplan; PIP, agreed with the EMA’s Pediatric Committee, or PDCO.the PDCO, (ii) a decision of the EMA granting a waiver from the obligation to provide the results of studies in the paediatric population in accordance with a PIP, or (iii) a decision by the EMA agreeing to a deferral of the initiation or completion of some or all of the measures set out in the PIP. The PIP sets out the timing and measures proposed to generate data to support a pediatric indication of the drug for which marketing authorization is being sought. The PDCO can grant a deferral of the obligation to implement some or all of the measures of the PIP until there are sufficient data to demonstrate the efficacy and safety of the product in adults. Further, the obligation to provide pediatric clinical trial data can be waived by the PDCO when these data is not needed or appropriate because the product is likely to be ineffective or unsafe in children, the disease or condition for which the product is intended occurs only in adult populations, or when the product does not represent a significant therapeutic benefit over existing treatments for pediatric patients. Once the marketing authorization is obtained in all Member States of the European Union and study results are included in the product information, even when negative, the product is eligible for six months’ supplementary protection certificate extension. For orphan-designated medicinal products, the10-year period of market exclusivity is extended to 12 years. At this time, we have not agreed to a PIP with the PDCO for TransCon GH,hGH, or any of our other product candidates.

Outside the U.S. and the EEA, approval procedures vary among countries and can involve additional clinical testing, and the time required to obtain approval may differ from that required to obtain FDA or EEA approval. Clinical trials conducted in one country may not be accepted by regulatory authorities in other countries. Approval by the FDA, EMA, or EEA Competent Authorities does not ensure approval by regulatory authorities in other countries, and approval by one or more foreign regulatory authorities does not ensure approval by regulatory authorities in other foreign countries or by the FDA, EMA or EEA Competent Authorities. However, a failure or delay in obtaining regulatory approval in one country may have a negative effect on the regulatory process in others. The foreign regulatory approval process may include all of the risks associated with obtaining FDA approval, EMA, or EEA Competent Authority. We may not be able to file for regulatory approvals or to do so on a timely basis, and even if we do file we may not receive necessary approvals to commercialize our products in any market.

We may be subject to healthcare laws, regulation and enforcement; our failure to comply with these laws could harm our results of operations and financial conditions.

Although we do not currently have any products on the market, once we begin commercializing our products, we may be subject to additional healthcare, statutory and regulatory requirements and enforcement by the U.S. federal government and the states and foreign governments in which we conduct our business. The laws that may affect our ability to operate as a commercial organization include:

Any action against us for violation of these laws, even if we successfully defend against it, could cause us to incur significant legal expenses and divert our management’s attention from the operation of our business. If our operations are found to be in violation of any of the laws described above or any other governmental laws and regulations that apply to us, we may be subject to penalties, including civil and criminal penalties, damages, fines, the curtailment or restructuring of our operations, the exclusion from participation in U.S. federal and state healthcare programs and imprisonment, any of which could adversely affect our ability to market our products and adversely impact our financial results.

We are subject to governmental regulation and other legal obligations, particularly related to privacy, data protection and information security, and we are subject to consumer protection laws that regulate our marketing practices and prohibit unfair or deceptive acts or practices. Our actual or perceived failure to comply with such obligations could harm our business.

We are subject to diverse laws and regulations relating to data privacy and security, including, in the United States, HIPAA and, in the EU and the European Economic Area, or EEA, Regulation 2016/679, known as the General Data Protection Regulation, or GDPR. New privacy rules are being enacted in the United States and globally, and existing ones are being updated and strengthened. Complying with these numerous, complex and often changing regulations is expensive and difficult, and failure to comply with any privacy laws or data security laws or any security incident or breach involving the misappropriation, loss or other unauthorized use or disclosure of sensitive or confidential patient or consumer information, whether by us, one of our business associates or another third-party, could adversely affect our business, financial condition and results of operations, including but not limited to: investigation costs, material fines and penalties; compensatory, special, punitive, and statutory damages; litigation; consent orders regarding our privacy and security practices; requirements that we provide notices, credit monitoring services and/or credit restoration services or other relevant services to impacted individuals; adverse actions against our licenses to do business; and injunctive relief. Furthermore, these rules are constantly changing; for example, the GDPR came into force in May 2018 changing the European regime. Before that, theUS-EU Safe Harbor framework was declared invalid in 2015 and replaced with theUS-EU Privacy Shield framework which, along with other methods which permit transfer under European privacy law, are under ongoing review and subject to challenge.

The privacy laws in the EU have been significantly reformed. On May 25, 2018, the GDPR entered into force and became directly applicable in all EU member states. The GDPR implements more stringent operational requirements than its predecessor legislation. For example, the GDPR requires us to make more detailed disclosures to data subjects, requires disclosure of the legal basis on which we can process personal data, makes it harder for us to obtain valid consent for processing, will require the appointment of data protection officers when sensitive personal data, such as health data, is processed on a large scale, provides more robust rights for data subjects, introduces mandatory data breach notification through the EU, imposes additional obligations on us when contracting with service providers and requires us to adopt appropriate privacy governance including policies, procedures, training and data audit. If we do not comply with our obligations under the GDPR, we could be exposed to fines of up to the greater of €20 million or up to 4% of our total global annual revenue in the event of a significant breach. In addition, we may be the subject of litigation and/or adverse publicity, which could adversely affect our business, results of operations and financial condition.

We cannot assure you that our third-party service providers with access to our or our customers’, suppliers’, trial patients’, and employees’ personally identifiable and other sensitive or confidential information in relation to which we are responsible will not breach contractual obligations imposed by us, or that they will not experience data security breaches or attempts thereof, which could have a corresponding effect on our business including putting us in breach of our obligations under privacy laws and regulations and/or which could in turn adversely affect our business, results of operations and financial condition. While we attempt to address the associated risks by performing security assessments and detailed due diligence, we cannot assure you that these contractual measures and our own privacy and security-related safeguards will protect us from the risks associated with the third-party processing, storage and transmission of such information.

Legislative or regulatory healthcare reforms in the United States may make it more difficult and costly for us to obtain regulatory clearance or approval of our product candidates in the United States and to produce, market and distribute our products in the United States after clearance or approval is obtained.

From time to time, legislation is drafted and introduced in U.S. Congress that could significantly change the statutory provisions governing the regulatory clearance or approval, manufacture, and marketing of regulated products or the reimbursement thereof. In addition, FDA regulations and guidance are often revised or reinterpreted by the FDA in ways that may significantly affect our business and our products. In addition, the new Trump administration has taken several executive actions, including the issuance of a number of Executive Orders, that could impose significant burdens on, or otherwise materially delay, the FDA’s ability to engage in routine oversight activities such as implementing statutes through rulemaking, issuance of guidance, and review and approval of marketing applications. It is difficult to predict how these requirements will be interpreted and implemented, and the extent to which they will impact the FDA’s ability to exercise its regulatory authority. If these executive actions impose restrictions on the FDA’s ability to engage in oversight and implementation activities in the normal course, our business may be negatively impacted. Any new regulations or revisions or reinterpretations of existing regulations may impose additional costs or lengthen review times of our product candidates. We cannot determine what effect changes in regulations, statutes, legal interpretation or policies, when and if promulgated, enacted or adopted may have on our business in the future. Such changes could, among other things, require:

December 14, 2018, a U.S. District Court Judge in the Northern District of Texas, ruled that the individual mandate is a critical and inseverable feature of the ACA, and therefore, because it was repealed as part of the Tax Act, the remaining provisions of the ACA are invalid as well. While the Trump Administration and the Centers for Medicare & Medicaid Services have both stated that the ruling will have no immediate effect, it is unclear how this decision, subsequent appeals and other efforts to repeal and replace the ACA will impact the ACA. There is still uncertainty with respect to the impact President Trump’s administration and the U.S. Congress may have, if any, and any changes will likely take time to unfold, and could have an impact on coverage and reimbursement for healthcare items and services covered by plans that were authorized by the Affordable Care Act. However, we cannot predict the ultimate content, timing or effect of any healthcare reform legislation or the impact of potential legislation on us.

In addition, other legislative changes have been proposed and adopted in the United States since the Affordable Care Act was enacted, including aggregate reductions of Medicare payments to providers of 2% per fiscal year, which went into effect on April 1, 2013 and will stay in effect through 2027 unless additional Congressional action is taken, further reductions to Medicare payments to several types of providers, including hospitals, and an increased statute of limitations period for the government to recover overpayments to providers from three to five years. Recently, there has also been heightened governmental scrutiny over the manner in which manufacturers set prices for their marketed products, which has resulted in several Congressional inquiries and proposed bills designed to, among other things, bring more transparency to product pricing, review the relationship between pricing and manufacturer patient programs, and reform government program reimbursement methodologies for pharmaceutical products. Individual states in the United States have also become increasingly active in passing legislation and implementing regulations designed to control pharmaceutical product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing.

We expect that additional U.S. local and national healthcare reform measures will be adopted within and outside the United States in the future, any of which could limit the amounts that governments will pay for healthcare products and services, which could result in reduced demand for our product candidates or additional pricing pressures. The continuing efforts of the U.S. government, insurance companies, managed care organizations and other payors of healthcare services to contain or reduce costs of healthcare may adversely affect the demand for any drug products for which we may obtain regulatory approval, our ability to set a price that we believe is fair for our products, our ability to obtain coverage and reimbursement approval for a product, our ability to generate revenues and achieve or maintain profitability, and the level of taxes that we are required to pay.

Risks Related to Our Intellectual Property

If our intellectual property related to our product candidates is not adequate, we may not be able to compete effectively in our market.

Our success depends in part on our ability to:

We will be able to protect our proprietary technologytechnologies from unauthorized use by third parties only to the extent that such proprietary rights are covered by valid and enforceable patents or are effectively maintained as trade secrets. Anynon-confidential disclosure to or misappropriation by third parties of our confidential or proprietary information could enable competitors to quickly duplicate or surpass our technological achievements, thus eroding our competitive position in our market. Where we elect to pursue patent protection on our proprietary technology,technologies, we file, prosecute and maintain international U.S., European and other national patent applications covering such technology.technologies, including in the United States, Europe, China, and other jurisdictions.

As of December 31, 2017, seventeen2018, twenty-four patents have been issued to us in the United States. Thirteen of theseSeventeen patents are directed to our TransCon technologytechnologies and threefour are directed to TransCon GH.hGH. In addition, as of December 31, 2017,2018, we have approximately 86112 issued patents in jurisdictions outside of the United States, at least 5465 of which are directed to our TransCon technology,technologies, and 2235 of which are directed to our product candidates. As of December 31, 2017,2018, our TransCon GHhGH is covered by six different patent families and an additional nine patent families covering the auto-injector device, our TransCon PTH is covered by fivesix different patent families and our TransCon CNP is covered by ten different patent families. Most members of these families are applications in an early stage, so it is impossible to make any statements regarding whether or not they will be granted. We are not aware of any challenge to our issued patents, in the United States, Europe or in any other jurisdiction.

The patent application process, also known as patent prosecution, is expensive and time-consuming, and we and our current or future licensors and licensees may not be able to prepare, file and prosecute all necessary or desirable patent applications at a reasonable cost or in a timely manner. It is also possible that we or our current licensors, or any future licensors or licensees, will fail to identify patentable aspects of inventions made in the course of development and commercialization activities before it is too late to obtain patent protection on them. Therefore, these and any of our patents and applications may not be prosecuted and enforced in a manner consistent with the best interests of our business. It is possible that defects of form in the preparation or filing of our patents or patent applications may exist, or may arise in the future, for example with respect to proper priority claims, inventorship, etc., although we are unaware of any such defects. If we or our current licensors or licensees, or any future licensors or licensees, fail to establish, maintain or protect such patents and other intellectual property rights, such rights may be reduced or eliminated. If our current licensors or licensees, or any future licensors or licensees, are not fully cooperative or disagree with us as to the prosecution, maintenance or enforcement of any patent rights, such patent rights could be compromised. If there are material defects in the form or preparation of our patents or patent applications, such patents or applications may be invalid and unenforceable. Any of these outcomes could impair our ability to prevent competition from third parties, which may harm our business.

The strength of patents in the biotechnology and pharmaceutical field involves complex legal and scientific questions and can be highly uncertain. The patent applications that we own or license may fail to result in issued patents in the United States or in other countries. Even if patents do issue on such patent applications, third parties may challenge the validity, enforceability or scope thereof, which may result in such patents being narrowed, invalidated or held unenforceable. For example, U.S. patents can be challenged by any person before the new USPTO Patent Trial and Appeals Board at any time within theone-year period following that person’s receipt of an allegation of infringement of the patents. Patents granted by the European Patent Office may be similarly opposed by any person within nine months from the publication of the grant. Similar proceedings are available in other jurisdictions, and in the United States, Europe and other jurisdictions third parties can raise questions of validity with a patent office even before a patent has granted. Furthermore, even if they are unchallenged, our patents and patent applications may not adequately protect our intellectual property or prevent others from designing around our claims. For example, a third party may develop a competitive product that provides therapeutic benefits similar to one or more of our product candidates but that has a different composition that falls outside the scope of our patent protection. If the breadth or strength of protection provided by the patents and patent applications we hold or pursue with respect to our product candidates is successfully challenged, then our ability to commercialize such product candidates could be negatively affected, and we may face unexpected competition that could have harm our business. Further, if we encounter delays in our clinical trials, the period of time during which we or our collaboration partners could market our product candidates under patent protection would be reduced.

The degree of future protection of our proprietary rights is uncertain. Patent protection may be unavailable or severely limited in some cases and may not adequately protect our rights or permit us to gain or keep our competitive advantage. For example:

If we or our current licensors or licensees, or any future licensors or licensees, fail to prosecute, maintain and enforce patent protection for our product candidates, our ability to develop and commercialize our product candidates could be harmed and we might not be able to prevent competitors from making, using and selling competing products. This failure to properly protect the intellectual property rights relating to our product candidates could harm our business, financial condition and operating results. Moreover, our competitors may independently develop equivalent knowledge, methods andknow-how.

Even where laws provide protection, costly and time-consuming litigation could be necessary to enforce and determine the scope of our proprietary rights, and the outcome of such litigation would be uncertain. If we or one of our collaboration partners were to initiate legal proceedings against a third party to enforce a patent covering the product candidate, the defendant could counterclaim that our patent is invalid and/or unenforceable. In patent litigation in the United States, defendant counterclaims alleging invalidity and/or unenforceability are commonplace. Grounds for a validity challenge could be an alleged failure to meet any of several statutory requirements, including lack of novelty, obviousness ornon-enablement. Patents may be unenforceable if someone connected with prosecution of the patent withheld relevant information from the USPTO, or made a misleading statement, during prosecution. The outcomes of proceedings involving assertions of invalidity and unenforceability are unpredictable. It is possible that prior art of which we and the patent examiner were unaware during prosecution exists, which would render our patents invalid. Moreover, it is also possible that prior art may exist that we are aware of, but that we do not believe are relevant to our current or future patents, that could nevertheless be determined to render our patents invalid. If a defendant were to prevail on a legal assertion of invalidity and/or unenforceability of our patents covering one of our product candidates, we would lose at least part, and perhaps all, of the patent protection on such product candidate. Such a loss of patent protection would harm our business. Moreover, our competitors could counterclaim in any suit to enforce our patents that we infringe their intellectual property. Furthermore, some of our competitors have substantially greater intellectual property portfolios, and resources, than we do.

If we are unable to prevent disclosure of our trade secrets or other confidential information to third parties, our competitive position may be impaired.

In addition to patents, we rely on trade secrets and proprietaryknow-how. We seek protection, in part, through confidentiality and proprietary information clauses in agreements with our collaboration partners, employees, consultants, outside scientific collaboration partners and sponsored researchers and other advisors. Although we generally require all of our employees, consultants, advisors and any third parties who have access to our proprietaryknow-how, information or technology to assign or grant similar rights to their inventions to us, and endeavor to execute confidentiality agreements with all such parties, we cannot be certain that we have executed such agreements with all parties who may have contributed to our intellectual property or who had access to our proprietary information, nor can we be certain that our agreements with such parties will not be breached. These agreements may not effectively prevent disclosure of confidential and proprietary information and may not provide an adequate remedy in the event of unauthorized use or disclosure of confidential and proprietary information. We cannot guarantee that our trade secrets and other confidential proprietary information will not be publicly disclosed or that competitors will not otherwise gain access to our trade secrets or independently develop substantially equivalent information and techniques. The failure to obtain or maintain trade secret protection could adversely affect our competitive business position.

If we are sued for infringing intellectual property rights of third parties, it will be costly and time consuming, and an unfavorable outcome in that litigation could harm our business.

Our commercial success depends significantly on our ability to operate without infringing, violating or misappropriating the patents and other proprietary rights of third parties. Our own technologies may infringe, violate or misappropriate the patents or other proprietary rights of third parties, or we may be subject to third-party claims of such infringement. Numerous U.S. and foreign issued patents and pending patent applications owned by third parties exist in the fields in which we are developing our product candidates. For example, we are aware of several issued patents related to auto-injection devices that may be relevant to our auto-injection device under development with Phillips Medisize A/S (formerly Medicom Innovation Partner A/S;S); however, we believe that these (i) will expire prior to our product launch, (ii) are invalid, and/or (iii) do not and will not cover our device. We cannot be certain that our product candidates will not infringe existing or future patents. Because patent applications can take many years to issue and may be confidential for 18 months or more after filing, and because pending patent claims can be revised before issuance, there may be applications now pending which may later result in issued patents that may be infringed by the manufacture, use or sale of our product candidates or our TransCon technology.technologies. We may not be aware of patents that have already issued that a third party might assert are infringed by our product candidates. It is also possible that patents of which we are aware, but which we do not believe are relevant to our product candidates, could nevertheless be found to be infringed by our product candidates. Nevertheless, we are not aware of any valid issued patents that we believe would prevent us from marketing our product candidates, if approved. Moreover, we may face patent infringement claims fromnon-practicing entities that have no relevant product revenue and against whom our own patent portfolio may thus have no deterrent effect.

In addition, we and our collaboration partners may face costly and time-consuming intellectual property litigation with the NDA holders and Orange Book patentees of the products in respect of which we seek to obtain FDA approval. Companies that produce branded pharmaceutical products for which there are listed patents in the FDA’s Orange Book routinely bring patent infringement litigation against applicants seeking FDA approval to manufacture and market branded and/or generic forms of their products. Accordingly, we may face patent litigation as a result of our submission of NDA applications to the FDA or as a result of submitting an MAA with the EMA.

Intellectual property litigation involves many risks and uncertainties, and there is no assurance that we will prevail in any lawsuit brought against us. Third parties making claims against us for infringement, violation or misappropriation of their intellectual property rights may seek and obtain injunctive or other equitable relief, which could effectively block our ability to further develop and commercialize our product candidates. Further, if a patent infringement suit were brought against us, we could be forced to stop or delay research, development, manufacturing or sales of the product or product candidate that is the subject of the suit. Defense of these claims, regardless of their merit, would cause us to incur substantial expenses and, would be a substantial diversion of resources from our business. In the event of a successful claim of any such infringement, violation or misappropriation, we may need to obtain licenses from such third parties and we and our collaboration partners may be prevented from pursuing product development or commercialization and/or may be required to pay damages. We cannot be certain that any licenses required under such patents or proprietary rights would be made available to us, or that any offer to license would be made available to us on commercially reasonable terms. If we cannot obtain such licenses, we and our collaboration partners may be restricted or prevented from manufacturing and selling products employing our technology.technologies. These adverse results, if they occur, could adversely affect our business, results of operations and prospects, and the value of our shares or ADSs.

We may become involved in lawsuits to protect or enforce our patents or other intellectual property, which could be expensive, time consuming and unsuccessful.

The biotechnology and pharmaceutical industries have been characterized by extensive litigation regarding patents and other intellectual property rights. The defense and prosecution of contractual or intellectual property lawsuits, USPTO interference or derivation proceedings, European Patent Office oppositions and related legal and administrative proceedings in the United States, Europe and other countries, involve complex legal and factual questions. As a result, such proceedings may be costly and time-consuming to pursue and their outcome is uncertain.

Litigation may be necessary to:

Competitors may infringe our intellectual property. As a result, we may be required to file infringement claims to stop third-partythird- party infringement or unauthorized use. This can be expensive, particularly for a company of our size, and time-consuming. In addition, in an infringement proceeding, a court may decide that a patent of ours is not valid or is unenforceable, or may refuse to stop the other party from using the technology at issue on the grounds that our patent claims do not cover its technology or that the factors necessary to grant an injunction against an infringer are not satisfied. An adverse determination of any litigation or other proceedings could put one or more of our patents at risk of being invalidated, interpreted narrowly, or amended such that they do not cover our product candidates. Moreover, such adverse determinations could put our patent applications at risk of not issuing, or issuing with limited and potentially inadequate scope to cover our product candidates or to prevent others from marketing similar products.

Interference, derivation or other proceedings brought at the USPTO, may be necessary to determine the priority or patentability of inventions with respect to our patent applications or those of our licensors or potential collaboration partners. Litigation or USPTO proceedings brought by us may fail or may be invoked against us by third parties. Even if we are successful, domestic or foreign litigation or USPTO or foreign patent office proceedings may result in substantial costs and distraction to our management. We may not be able, alone or with our licensors or potential collaboration partners, to prevent misappropriation of our proprietary rights, particularly in countries where the laws may not protect such rights as fully as in the United States.

Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation or other proceedings, there is a risk that some of our confidential information could be compromised by disclosure during this type of litigation or other proceedings. In addition, during the course of this kind of litigation or proceedings, there could be public announcements of the results of hearings, motions or other interim proceedings or developments or public access to related documents. If investors perceive these results to be negative, the market price for the ADSs could be significantly harmed.

Changes to the patent law in the United States and other jurisdictions could diminish the value of patents in general, thereby impairing our ability to protect our products.

As is the case with other biopharmaceutical companies, our success is heavily dependent on intellectual property, particularly patents. Obtaining and enforcing patents in the biopharmaceutical industry involves both technological and legal complexity and is therefore costly, time consuming and inherently uncertain. Recent patentPatent reform legislation in the United States and other countries, including the Leahy-Smith America Invents Act, or Leahy-Smith Act, signed into law on September 16, 2011, could increase those uncertainties and costs. The Leahy-Smith Act includes a number of significant changes to U.S. patent law. These include provisions that affect the way patent applications are prosecuted, redefine prior art and provide more efficient and cost-effective avenues for competitors to challenge the validity of patents. In addition, the Leahy-SmithLeahy- Smith Act has transformed the U.S. patent system into a “first to file” system. Thefirst-to-file provisions, however, only became effective on March 16, 2013. Accordingly, it is not yet clear what, if any, impact the Leahy-Smith Act will have on the operation of our business. However, the Leahy-Smith Act and its implementation could make it more difficult to obtain patent protection for our inventions and increase the uncertainties and costs surrounding the prosecution of our or our collaboration partners’ patent applications and the enforcement or defense of our or our collaboration partners’ issued patents, all of which could harm our business, results of operations and financial condition.

The U.S. Supreme Court has ruled on several patent cases in recent years, either narrowing the scope of patent protection available in certain circumstances or weakening the rights of patent owners in certain situations. Additionally, there have been recent proposals for additional changes to the patent laws of the United States and other countries that, if adopted, could impact our ability to obtain patent protection for our proprietary technologytechnologies or our ability to enforce our proprietary technology.technologies. Depending on future actions by the U.S. Congress, the U.S. courts, the USPTO and the relevantlaw-making bodies in other countries, the laws and regulations governing patents could change in unpredictable ways that would weaken our ability to obtain new patents or to enforce our existing patents and patents that we might obtain in the future.

Certain of our employees and patents are subject to German law.

As of December 31, 2017, 522018, 61 of our employees work in Germany and are subject to German employment law. Ideas, developments, discoveries and inventions made by such employees are generally subject to the provisions of the German Act on Employees’ Inventions, which regulates the ownership of, and compensation for, inventions made by employees. Under this act, we face the risk that we may be required to pay additional compensation for assigned patent rights and disputes can occur between us and our employees orex-employees pertaining to allegednon-adherence to the provisions of this act that may be costly to defend and consume our management’s time and efforts whether we prevail or fail in such dispute. In addition, under the German Act on Employees’ Inventions, certain employees may have retained rights to patents they invented orco-invented before October 2009. Although substantially all of these employees have assigned their interest in these patents to us, to the extent permitted by law, there is a risk that the compensation we provided to them may be deemed to be insufficient and we may be required under German law to increase the compensation due to such employees for the use of the patents. In those cases where employees have not assigned their interests to us, we may need to pay compensation for the use of those patents. If we are required to pay additional compensation or face other disputes under the German Act on Employees’ Inventions, our results of operations could be adversely affected.

Obtaining and maintaining our patent protection depends on compliance with various procedural, document submission, fee payment and other requirements imposed by governmental patent agencies, and our patent protection could be reduced or eliminated fornon-compliance with these requirements.

The USPTO and various foreign patent agencies require compliance with a number of procedural, documentary, fee payment and other provisions to maintain patent applications and issued patents. Noncompliance with these requirements can result in abandonment or lapse of a patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction. Losing our patent rights could enable competitors to enter the market earlier than would otherwise have been the case.

We have not yet registered trademarks for a commercial trade name for any of our product candidates in the United States or elsewhere and failure to secure such registrations could adversely affect our business.

We use various trademark rights in our business, including, Ascendis, and our trade name TransCon. Ascendis is our only registered trademark in the United States. We may not be able to obtain trademark protection in other territories that we consider of significant importance to us. Furthermore, we have not yet registered trademarks for a commercial trade name for any of our product candidates in the United States or elsewhere. During trademark registration proceedings, our trademark applications may be rejected. Although we are given an opportunity to respond to those rejections, we may be unable to overcome such rejections. In addition, in the USPTO and in comparable agencies in many foreign jurisdictions, third parties can oppose pending trademark applications and seek to cancel registered trademarks. Opposition or cancellation proceedings may be filed against our trademarks, and our trademarks may not survive such proceedings. In the event that our trademarks are successfully challenged, we could be forced to rebrand our products, which could result in loss of brand recognition and could require us to devote resources to advertising and marketing our products under new brands.

As a result of the United Kingdom’s referendum on exiting the European Union our trademark is likely to require some form ofre-registration in the UK. While this is assumed to be a purely administrative act, we may accidentally not perform all required steps in time which may lead to a lapse of our trademark in the UK.

Moreover, any name we propose to use with our product candidates in the United States must be approved by the FDA, regardless of whether we have registered it, or applied to register it, as a trademark. The FDA typically conducts a review of proposed product names, including an evaluation of potential for confusion with other product names. If the FDA objects to any of our proposed proprietary product names, we may be required to expend significant additional resources in an effort to identify a suitable substitute name that would qualify under applicable trademark laws, not infringe the existing rights of third parties and be acceptable to the FDA.

We may not be able to enforce our intellectual property rights throughout the world.

Filing, prosecuting and defending patents on our product candidates in all countries throughout the world would be prohibitively expensive. The requirements for patentability may differ in certain countries, particularly in developing countries. Moreover, our ability to protect and enforce our intellectual property rights may be adversely affected by unforeseen changes in foreign intellectual property laws. Additionally, laws of some countries outside of the United States and Europe do not afford intellectual property protection to the same extent as the laws of the United States and Europe. Many companies have encountered significant problems in protecting and defending intellectual property rights in certain foreign jurisdictions. The legal systems of some countries, including India, China and other developing countries, do not favor the enforcement of patents and other intellectual property rights. This could make it difficult for us to stop the infringement of our patents or the misappropriation of our other intellectual property rights. For example, many foreign countries have compulsory licensing laws under which a patent owner must grant licenses to third parties. Consequently, we may not be able to prevent third parties from practicing our inventions in certain countries outside the United States and many countries in Europe. Competitors may use our technologies in jurisdictions where we have not obtained patent protection to develop their own products and, further, may export otherwise infringing products to territories where we have patent protection, if our ability to enforce our patents to stop infringing activities is inadequate. These products may compete with our products, and our patents or other intellectual property rights may not be effective or sufficient to prevent them from competing.

Proceedings to enforce our patent rights in foreign jurisdictions, whether or not successful, could result in substantial costs and divert our efforts and resources from other aspects of our business. Furthermore, while we intend to protect our intellectual property rights in major markets for our products, we cannot ensure that we will be able to initiate or maintain similar efforts in all jurisdictions in which we may wish to market our products. Accordingly, our efforts to protect our intellectual property rights in such countries may be inadequate.

We may be subject to claims that we or our employees have misappropriated the intellectual property, includingknow-how or trade secrets, of a third party, or claiming ownership of what we regard as our own intellectual property.

Many of our employees, consultants and contractors were previously employed at or engaged by other biotechnology or pharmaceutical companies, including our competitors or potential competitors. Some of these employees, consultants and contractors, executed proprietary rights,non-disclosure andnon-competition agreements in connection with such previous employment. Although we try to ensure that our employees, consultants and contractors do not use the intellectual property, proprietary information,know-how or trade secrets of others in their work for us, we may be subject to claims that we or these employees, consultants and contractors have used or disclosed such intellectual property, includingknow-how, trade secrets or other proprietary information. Litigation may be necessary to defend against these claims. If we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights or personnel, or access to consultants and contractors. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management.

In addition, while we typically require our employees, consultants and contractors who may be involved in the development of intellectual property to execute agreements assigning such intellectual property to us, we may be unsuccessful in executing such an agreement with each party who in fact develops intellectual property that we regard as our own, which may result in claims by or against us related to the ownership of such intellectual property. If we fail in prosecuting or defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights. Even if we are successful in prosecuting or defending against such claims, litigation could result in substantial costs and be a distraction to our senior management and scientific personnel.

Risks Related to Our Ordinary Shares and ADSs

The price of our ADSs may be volatile, and ADS holders may not be able to resell our ADSs at or above the price they paid.

The trading price of our ADSs could be highly volatile and could be subject to wide fluctuations in response to various factors, some of which are beyond our control. These factors include those discussed in this “Risk Factors” section of this annual report and others such as:

In addition, the stock markets in general, and the markets for pharmaceutical, biopharmaceutical and biotechnology stocks in particular, have experienced extreme volatility that may have been unrelated to the operating performance of the issuer. These broad market fluctuations may adversely affect the trading price or liquidity of our ADSs. In the past, when the market price of a stock has been volatile, holders of that stock have sometimes instituted securities class action litigation against the issuer. If any of the holders of shares or ADSs were to bring such a lawsuit against us, we could incur substantial costs defending the lawsuit and the attention of our senior management would be diverted from the operation of our business, which could seriously harm our financial position. Any adverse determination in litigation could also subject us to significant liabilities.

ADS holders do not directly hold our ordinary shares and do not have the rights of a holder of our ordinary shares.

ADS holders are not treated as our shareholders and do not have the rights of a holder of our ordinary shares. Danish law governs shareholder rights. Our depositary, Bank of New York Mellon, is the holder of the ordinary shares underlying our ADSs. The deposit agreement among us, the depositary, and all other persons directly and indirectly holding ADSs, sets out ADS holder rights as well as the rights and obligations of the depositary. In addition, our depositary charges certain fees to holders of our ADSs as set forth in “Item 12 D. Description of Securities Other than Equity Securities –American Depositary Shares.”

ADS holders may not be able to exercise their right to vote the ordinary shares underlying their ADSs.

Holders of ADSs may exercise voting rights with respect to the ordinary shares represented by the ADSs only in accordance with the provisions of the deposit agreement and not as a direct shareholder in the Company. The deposit agreement provides that, upon receipt of notice of any meeting of holders of our ordinary shares, the depositary will fix a record date for the determination of ADS holders who shall be entitled to give instructions for the exercise of voting rights. Upon timely receipt of notice from us, if we so request, the depositary shall distribute to the holders as of the record date (1) the notice of the meeting or solicitation of consent or proxy sent by us and (2) a statement as to the manner in which instructions may be given by the holders. However, we may not request the depositary to distribute this information which could effectively limit the ability of ADS holders to direct voting of the ordinary shares underlying their ADSs.

ADS holders may instruct the depositary of their ADSs to vote the ordinary shares underlying their ADSs. Otherwise, ADS holders are not able to exercise their right to vote, unless they withdraw the ordinary shares underlying the ADSs they hold. However, they may not know about the meeting far enough in advance to withdraw those ordinary shares. If we ask for instructions from ADS holders, the depositary, upon timely notice from us, will notify the ADS holders of the upcoming vote and arrange to deliver our voting materials to the ADS holders. We cannot guarantee that ADS holders will receive the voting materials in time to ensure that such holders can instruct the depositary to vote the ordinary shares underlying their ADSs or to withdraw the ordinary shares underlying their ADSs so that they can vote such shares directly. If the depositary does not receive timely voting instructions from an ADS holder, the depositary may give a proxy to a person designated by us to vote the ordinary shares underlying ADSs. In addition, the depositary and its agents are not responsible for failing to carry out voting instructions or for the manner of carrying out voting instructions. This means that ADS holders may not be able to exercise any right to vote, and there may be nothing an ADS holder can do if the ordinary shares underlying their ADSs are not voted as they requested.

An ADS holder may be subject to limitations on the transfer of their ADSs and the withdrawal of the underlying ordinary shares.

ADSs, which may be evidenced by American Depositary Receipts, or ADRs, are transferable on the books of the depositary. However, the depositary may close its books at any time or from time to time when it deems expedient in connection with the performance of its duties. The depositary may refuse to deliver, transfer or register transfers of ADSs generally when our books or the books of the depositary are closed, or at any time if we or the depositary think it is advisable to do so because of any requirement of law, government or governmental body, or under any provision of the deposit agreement, or for any other reason subject to an ADS holders’ right to cancel their ADSs and withdraw the underlying ordinary shares. Temporary delays in the cancellation of ADSs and withdrawal of the underlying ordinary shares may arise because the depositary has closed its transfer books or we have closed our transfer books, the transfer of ordinary shares is blocked to permit voting at a shareholders’ meeting or we are paying a dividend on our ordinary shares. In addition, an ADS holder may not be able to cancel their ADS and withdraw the underlying ordinary shares when such holder owes money for fees, taxes and similar charges and when it is necessary to prohibit withdrawals to comply with any laws or governmental regulations that apply to ADSs or to the withdrawal of ordinary shares or other deposited securities.

We have broad discretion to determine how to use the funds raised in our public offerings, and may use them in ways that may not enhance our operating results or the price of our ordinary shares and ADSs.

Our senior management has broad discretion over the use of proceeds from our public offerings, and we could spend the proceeds from those public offerings in ways the holders of shares or ADSs may not agree with or that do not yield a favorable return, if at all. We currently intend to use substantially all of the net proceeds from those public offerings to support the clinical development, and regulatory approval ofand commercial preparations for TransCon GH,hGH, to fund clinical development of our other rare disease endocrinology programs, including TransCon PTH and TransCon CNP, to identify and progress development of new product candidates, including in newthe therapeutic areas, to strengthen our TransCon technologyarea of oncology, and for working capital and general corporate purposes. However, our use of these proceeds may differ substantially from our current plans. If we do not invest or apply these proceeds in ways that improve our operating results, we may fail to achieve expected financial results, which could cause the price of the ADSs to decline.

If securities or industry analysts do not publish research or reports about our business, or if they issue an adverse or misleading opinion regarding our ordinary shares or ADSs, the price of the ADSs and trading volume could decline.

The trading market for the ADSs may be influenced by the research and reports that industry or securities analysts publish about us or our business. If any of the analysts who cover us issue an adverse or misleading opinion regarding us, our business model, our intellectual property or our stock performance, or if our clinical

trials and operating results fail to meet the expectations of analysts, the price of our ADSs would likely decline. If one or more of these analysts cease coverage of us or fail to publish reports on us regularly, we could lose visibility in the financial markets, which in turn could cause the price of our ADSs or trading volume to decline.

If we issue shares or ADSs in future financings, shareholders or holders of ADSs may experience immediate dilution and, as a result, the price of our ADSs may decline.

We may from time to time issue additional shares or ADS at a discount from the trading price of our ADSs. As a result, our shareholders and holders of ADSs would experience immediate dilution upon the issuance of ADSs at such discount. In addition, as opportunities present themselves, we may enter into financing or similar arrangements in the future, including the issuance of debt securities, preference share, ADSs or ordinary shares. If we issue shares or securities convertible into shares of our share capital, our ordinary shareholders and holders of ADSs would experience additional dilution and, as a result, the price of our ADSs may decline.

Sales of a substantial number of our ordinary shares or ADSs in the public market could cause the price of the ADSs to fall.

If our existing shareholders or holders of ADSs sell, or indicate an intention to sell, substantial amounts of our ordinary shares or ADSs in the public market, the trading price of our ADSs could decline. Based upon the number of shares outstanding as of March 1, 2018,2019, we have outstanding a total of 41,523,76542,135,448 ordinary shares. Of those shares, approximately 7,199,5327,528,823 were owned by current board members, members of our senior management and their respective affiliates, or may otherwise be subject to Rule 144 under the Securities Act. In addition, pursuant to a registration statement on FormF-3 filed in February 2016, 5,825,7303,706,148 of our ordinary shares are registered for resale by certain selling shareholders, including shareholders that are affiliated with members of our board of directors.

As of December 31, 2017,2018, there were 4,621,1545,611,629 warrants outstanding. If these warrants are exercised an additional 4,621,1545,611,629 ordinary shares or ADSs will become eligible for sale in the public market to the extent permitted by the provisions of various vesting schedules and Rule 144 and Rule 701 under the Securities Act. If these additional ordinary shares or ADSs are sold, or if it is perceived that they will be sold, in the public market, the trading price of the ADSs could decline. Any sales of securities by these security holders could have a negative effect on the trading price of the ADSs.

Our principal shareholders and senior management own a significant percentage of our shares and are able to exert significant control over matters subject to shareholder approval.

As of March 1, 20182019, our senior management, board members, holders of 5% or more of our share capital and their respective affiliates beneficially own approximately 58.8%57.2% of our outstanding voting securities. As a result, these security holders have the ability either alone or voting together as a group to determine and/or significantly influence the outcome of matters submitted to our shareholders for approval, including the election and removal of board members, payment of dividends, amendments to our articles of association, including changes to our share capital or any mergers, demergers, liquidations and similar transactions. This may prevent or discourage unsolicited acquisition proposals or offers for our ordinary shares or ADSs that our shareholders or ADS holders may feel are in their best interest as a shareholder or holder of ADSs. In addition, this group of shareholders may have the ability to control our management and affairs. Such control and concentration of ownership may affect the market price of the ADSs and may discourage certain types of transactions, including those involving actual or potential change of control of us (whether through merger, consolidation, take-over or other business combination), which might otherwise have a positive effect on the market price of the ADSs.

The rights of our shareholders may be different from the rights of shareholders in companies governed by the laws of U.S. jurisdictions.

Our corporate affairs are governed by our articles of association and by the laws governing companies incorporated in Denmark, including the Danish Companies Act. The rights of shareholders and the responsibilities of members of our board of directors may be different from the rights and obligations of shareholders in companies governed by the laws of U.S. jurisdictions. In the performance of its duties, our board of directors is required by Danish law to consider the interests of our company, its shareholders and its creditors. It is possible that some of these parties will have interests that are different from, or in addition to, the interests of our shareholders or the holders of our ADS.

Claims of U.S. civil liabilities may not be enforceable against us.

We are incorporated under the laws of Denmark. Substantially all of our assets are located outside the United States. A significant portion of our board members and employees reside outside the United States. As a result, it may not be possible for investors to effect service of process within the United States upon such persons or to enforce against them or us in U.S. courts, including judgments predicated upon the civil liability provisions of the U.S. securities laws of the United States.

The United States and Denmark currently do not have a treaty providing for the reciprocal recognition and enforcement of judgments, other than arbitration awards, in civil and commercial matters. Consequently, a final judgment for payment given by a court in the United States, whether or not predicated solely upon U.S. securities laws, would not automatically be recognized or enforceable in Denmark. To obtain a judgment which is enforceable in Denmark, the party in whose favor a final and conclusive judgment of the U.S. court has been rendered will be required to file its claim with a court of competent jurisdiction in Denmark. Such party may submit to the Danish court the final judgment rendered by the U.S. court. If and to the extent that the Danish court finds that the jurisdiction of the U.S. court has been based on grounds which are internationally acceptable and that proper legal procedures have been observed, the Danish court should, in principle, give binding effect to the judgment of the U.S. court, unless such judgment contravenes principles of public policy of Denmark. Danish courts are likely to deny the recognition and enforcement of punitive damages or other awards. Moreover, a Danish court may reduce the amount of damages granted by a U.S. court and recognize damages only to the extent that they are necessary to compensate actual losses or damages. Enforcement and recognition of judgments of U.S. courts in Denmark are solely governed by the provisions of the Danish Civil Procedure Code.

Based on the lack of a treaty as described above, U.S. investors may not be able to enforce against us or members of our board of directors, our executive board, our senior management or certain experts named herein who are residents of Denmark or countries other than the United States any judgments obtained in U.S. courts in civil and commercial matters, including judgments under the U.S. federal securities laws.

We qualify as a foreign private issuer and, as a result, we will not be subject to U.S. proxy rules and will be subject to Exchange Act reporting obligations that, to some extent, are more lenient and less frequent than those of a U.S. domestic public company.

We report under the Exchange Act, as anon-U.S. company with foreign private issuer status. Because we qualify as a foreign private issuer under the Exchange Act and although we are subject to Danish laws and regulations with regard to such matters and intend to furnish quarterly financial information to the SEC, we are exempt from certain provisions of the Exchange Act that are applicable to U.S. domestic public companies, including (i) the sections of the Exchange Act regulating the solicitation of proxies, consents or authorizations in respect of a security registered under the Exchange Act; (ii) the sections of the Exchange Act requiring insiders to file public reports of their stock ownership and trading activities and liability for insiders who profit from trades made in a short period of time; and (iii) the rules under the Exchange Act requiring the filing with the SEC of quarterly reports on Form10-Q containing unaudited financial and other specified information, or current reports on Form8-K, upon the occurrence of specified significant events. In addition, foreign private issuers are not required to file their annual report on Form20-F until four months after the end of each fiscal year, while U.S. domestic issuers that are accelerated filers are required to file their annual report on Form10-K within 75 days after the end of each fiscal year. Foreign private issuers are also exempt from the Regulation Fair Disclosure, aimed at preventing issuers from making selective disclosures of material information. As a result of the above, our shareholders and the holders of our ADS may not have the same protections afforded to shareholders of companies that are not foreign private issuers.

Our status as a “foreign private issuer” allows us to adopt International Financial Reporting Standards, or IFRS, accounting principles, which are different than accounting principles under U.S. Generally Accepted Accounting Principles, or U.S. GAAP.

We have adopted and presented our consolidated financial statements in accordance with International Financial Reporting Standards as issued by the International Accounting Standards Board. IFRS is an internationally recognized body of accounting principles that are used by many companies outside of the United States to prepare their financial statements; and the SEC recently permitted foreign private issuers such as our company to prepare and file their financial statements in accordance with IFRS rather than U.S. GAAP. IFRS accounting principles are different from those of U.S. GAAP, and SEC rules do not require us to provide a reconciliation of IFRS accounting principles to those of U.S. GAAP. Investors who are not familiar with IFRS may misunderstand certain information presented in our consolidated financial statements. Accordingly, we suggest that readers of our consolidated financial statements familiarize themselves with the provisions of IFRS accounting principles to better understand the differences between these two sets of principles.

As a foreign private issuer and as permitted by the listing requirements of The NASDAQthe Nasdaq Global Select Market, we rely on certain home country governance practices rather than the corporate governance requirements of The NASDAQthe Nasdaq Global Select Market.

We qualify as a foreign private issuer. As a result, in accordance with the listing requirements of The NASDAQthe Nasdaq Global Select Market, we rely on home country governance requirements and certain exemptions thereunder rather than relying on the corporate governance requirements of The NASDAQthe Nasdaq Global Select Market. For instance, the Listing Rules for the NASDAQNasdaq Stock Market, or the NASDAQNasdaq Listing Rules, for domestic U.S. issuers require listed companies to have, among other things, a majority of their board members be independent, and to have independent director oversight of executive compensation, nomination of board members and corporate governance matters. As a foreign private issuer, however, while we intend to comply with these requirements, we are permitted to follow home country practice in lieu of the above requirements. Danish law does not require that a majority of our board consist of independent directors or the implementation of a remuneration committee or nominating and corporate governance committee, and our board may thus in the future not include, or include fewer, independent directors than would be required if we were subject to the NASDAQNasdaq Listing Rules, or they may decide that it is in our interest not to have a remuneration committee or nominating and corporate governance committee, or have such committees governed by practices that would not comply with NASDAQNasdaq Listing Rules. Since a majority of our board of directors may not consist of independent directors if we decide to rely on the foreign private issuer exemption to the NASDAQNasdaq Listing Rules, our board’s approach may, therefore, be different from that of a board with a majority of independent directors, and as a result, the management oversight of our company could, in the future, be more limited than if we were subject to the NASDAQNasdaq Listing Rules. We intend to follow home country practice with regard to, among other things, quorum requirements generally applicable to general meetings of shareholders.

Furthermore, Danish law does not have a regulatory regime for the solicitation of proxies and the solicitation of proxies is not a generally accepted business practice in Denmark, thus our practice varies from the requirement of NASDAQNasdaq Listing Rule 5620(b). In addition, our shareholders have authorized our board of directors to issue securities including in connection with certain events such as the acquisition of shares or assets of another company, the establishment of or amendments to equity-based compensation plans for employees, a change of control of us, rights issues at or below market price, certain private placements and issuance of convertible notes. To this extent, our practice varies from the requirements of NASDAQNasdaq Rule 5635, which generally requires an issuer to obtain shareholder approval for the issuance of securities in connection with such events. Accordingly, our shareholders and holders of our ADS may not have the same protections afforded to shareholders of companies that are subject to these NASDAQNasdaq requirements.

We may lose our foreign private issuer status, which would then require us to comply with the Exchange Act’s domestic reporting regime and cause us to incur significant legal, accounting and other expenses.

We qualify as a foreign private issuer and therefore we are not required to comply with all of the periodic disclosure and current reporting requirements of the Exchange Act applicable to U.S. domestic issuers. We may no longer be a foreign private issuer as of June 30, 2018,2019, which would require us to comply with all of the

periodic disclosure and current reporting requirements of the Exchange Act applicable to U.S. domestic issuers as of January 1, 2019.2020. To maintain our current status as a foreign private issuer, either (a) a majority of our ordinary shares or ADSs must be either directly or indirectly owned of record bynon-residents of the United States or (b)(i) a majority of our executive officers or directors may not be U.S. citizens or residents, (ii) more than 50% of our assets cannot be located in the United States and (iii) our business must not be administered principally inside the United States. If we lost this status, we would be required to comply with the Exchange Act reporting and other requirements applicable to U.S. domestic issuers, which are more detailed and extensive than the requirements for foreign private issuers. We may also be required to make changes in our corporate governance practices in accordance with various SEC and NASDAQNasdaq rules. The regulatory and compliance costs to us under U.S. securities laws if we are required to comply with the reporting requirements applicable to a U.S. domestic issuer may be significantly higher than the cost we would incur as a foreign private issuer. As a result, we expect that a loss of foreign private issuer status would increase our legal and financial compliance costs and would make some activities highly time consuming and costly. We also expect that if we were required to comply with the rules and regulations applicable to U.S. domestic issuers, it would make it more difficult and expensive for us to obtain director and officer liability insurance, and we may be required to accept reduced coverage or incur substantially higher costs to obtain coverage. These rules and regulations could also make it more difficult for us to attract and retain qualified members of our board of directors.

We may be a “passive foreign investment company” for U.S. federal income tax purposes for our current taxable year and future taxable years, which could result in adverse U.S. federal income tax consequences to U.S. investors.

Under the Internal Revenue Code of 1986, as amended, the determination of passive foreign investment company, or PFIC, status is fact-specific, and generally cannot be made until after the close of the taxable year in question. Although we do not believe we were a PFIC for U.S. federal income tax purposes for our taxable year ended December 31, 2017,2018, we may be a PFIC for our current taxable year and future taxable years. Anon-U.S. corporation will be considered a PFIC for any taxable year if either (1) at least 75% of its gross income for such year is passive income or (2) at least 50% of the value of its assets (based on an average of the quarterly values of the assets during such year) is attributable to assets that produce or are held for the production of passive income. A separate determination must be made each taxable year as to whether we are a PFIC (after the close of each such taxable year). If we are a PFIC for any taxable year during which a U.S. Holder (as defined in “Item 10 E. Additional Information—Taxation—Material U.S. Federal Income Tax Consequences to U.S. Holders”) holds ordinary shares or ADSs, the U.S. Holder may be subject to adverse tax consequences, including (i) the treatment of all or a portion of any gain on disposition as ordinary income, (ii) the application of an interest charge with respect to such gain and certain dividends and (iii) compliance with certain reporting requirements. Each U.S. Holder is strongly urged to consult its tax advisor regarding these issues. See “Item 10 E. Additional Information—Taxation—Material U.S. Federal Income Tax Consequences to U.S. Holders.”

If a United States person is treated as owning at least 10% of our ordinary shares or ADSs, such holder may be subject to adverse U.S. federal income tax consequences.

If a U.S. Holder (as defined in “Item 10 E. Additional Information—Taxation—Material U.S. Federal Income Tax Consequences to U.S. Holders”) is treated as owning (directly, indirectly or constructively) at least 10% of the value or voting power of our ordinary shares or ADSs, such U.S. Holder may be treated as a “United States shareholder” with respect to each “controlled foreign corporation” in our group (if any). IfBecause our group includes one or more U.S. subsidiaries, certain of ournon-U.S. subsidiaries could be treated as controlled“controlled foreign corporationscorporations” (regardless of whether we are treated as a controlled“controlled foreign corporation)corporation”). A United“United States shareholdershareholder” of a controlled“controlled foreign corporationcorporation” may be required to report annually and include in its U.S. taxable income its pro rata share of “Subpart F income,” “global intangiblelow-taxed income” and investments in U.S. property by controlled“controlled foreign corporations,” regardless of whether we make any distributions. An individual that is a United“United States shareholdershareholder” with respect to a controlled“controlled foreign corporationcorporation” generally would not be allowed certain tax deductions or foreign tax credits that would be allowed to a United“United States shareholdershareholder” that is a U.S. corporation. Failure to comply with these reporting obligations may subject you to significant monetary penalties and may prevent the statute of limitations from starting with respect to your U.S. federal income tax return for the year for

which reporting was due. We cannot provide any assurances that we will assist investors in determining whether any of ournon-U.S. subsidiaries are treated as a controlled“controlled foreign corporationcorporation” or whether such investor is treated as a United“United States shareholdershareholder” with respect to any of such controlled“controlled foreign corporations.” Further, we cannot provide any assurances that we will furnish to any United“United States shareholdersshareholders” information that may be necessary to comply with the aforementioned reporting and tax payment obligations. U.S. Holders should consult their tax advisors regarding the potential application of these rules to their investment in our ordinary shares or ADSs.

We do not currently intend to pay dividends on our ordinary shares or ADSs, and, consequently, our shareholders’ and ADS holders’ ability to achieve a return on their investment will depend on appreciation in the price of the ADSs or our ordinary shares.

We do not currently intend to pay any cash dividends on our ordinary shares for the foreseeable future. We currently intend to invest our future earnings, if any, to fund our growth. Therefore, our shareholders and ADS holders are not likely to receive any dividends on their investment for the foreseeable future. Because we do not intend to pay dividends, our shareholders’ and ADS holders’ ability to receive a return on their investment will depend on any future appreciation in the market value of our ADSs. There is no guarantee that our ordinary shares or ADSs will appreciate or even maintain the price at which our holders have acquired them.

Investors should be aware that the rights provided to our shareholders and holders of ADSs under Danish corporate law and our articles of association differ in certain respects from the rights that would typically be provided to a shareholder of a U.S. company under applicable U.S. federal and state laws.

Under Danish corporate law, except in certain limited circumstances (which require as a minimum that a proposal for inspection has been supported by a minimum of 25% of the shareholders voting and being present at a general meeting), our shareholders may not ask for an inspection of our corporate records, while under Delaware corporate law any shareholder, irrespective of the size of such shareholder’s shareholdings, may do so. Shareholders of a Danish limited liability company are also unable to initiate a derivative action, a remedy typically available to shareholders of U.S. companies, to enforce a right of our company, in case we fail to enforce such right ourselves, other than in certain cases of board member/management liability under limited circumstances. In addition, a majority of our shareholders may release a board member or manager from any claim of liability we may have, including if such board member or manager has acted in bad faith or has breached his/her duty of loyalty and only if a minority of at least 10% of the shareholders represented at the relevant general meeting have opposed the decision, may a shareholder bring a derivative action on behalf of our company. In contrast, most U.S. federal and state laws prohibit a company or its shareholders from releasing a board member from liability altogether if such board member has acted in bad faith or has breached such board member’s duty of loyalty to our company. Additionally, distribution of dividends from Danish companies to foreign companies and individuals can be eligible fornon-refundable withholding tax, and not all receiving countries allow for deduction. Also, the rights as a creditor may not be as strong under Danish insolvency law, as under U.S. law or other insolvency law, and consequently creditors may recover less in the event our company is subject to insolvency compared to a similar case including a U.S. debtor. In addition, the use of the tax asset consisting of the accumulated tax deficit requires that we are able to generate positive taxable income and can be restricted by future amendments to Danish tax law. Finally, Danish corporate law may not provide appraisal rights in the case of a business combination equivalent to those generally afforded a shareholder of a U.S. company under applicable U.S. laws. As a result of these differences between Danish corporate law and our articles of association, on the one hand, and U.S. federal and state laws, on the other hand, in certain instances, shareholders and ADS holders could receive less protection as an equity holder of our company than they would as a shareholder of a U.S. company.

Holders of our ordinary shares or ADSs may not be able to exercise theirpre-emptive subscription rights and may suffer dilution of their equityholdingequity holding in the event of future issuances of our shares.

Under the Danish Companies Act, our shareholders benefit from apre-emptive subscription right on the issuance of ordinary shares for cash consideration only and not in the event of issuance of shares againstnon-cash contribution or debt conversion. Even the shareholders’pre-emptive subscription rights in the event of issuances of shares against cash payment may be disapplied by a resolution of the shareholders at a general meeting of our shareholders and/or the shares or ADSs may be issued on the basis of an authorization granted

to the board of directors pursuant to which the board may disapply the shareholders’pre-emptive subscription rights. Such shares or ADSs may be issued above, or at market value as well as by way of incorporation of available reserves (including premium). In addition, a shareholder may not be able to exercise the shareholder’spre-emptive right on a timely basis or at all, unless the shareholder complies with the Danish Companies Act and applicable laws in the jurisdiction in which the shareholder is resident. Furthermore, the use ofpre-emptive subscription rights in relation to future capital increases in our company can be restricted for U.S. residents according to U.S. securities law. As a result, the shareholding or holders of ADSs of such shareholders or ADS holders may be materially diluted in the event shares or ADSs are issued in the future. Shares or ADSs may be issued at a discount to market price in rights offerings provided that the resolution is approved bytwo-thirds of the votes cast and the share capital represented at the general meeting and in these cases a restriction on the ability to exercisepre-emptive rights may materially dilute the value of the ordinary shares or ADSs held by the shareholder or ADS holder in question. Rights issues may also be carried out by the board of directors according to valid authorizations in our articles of association.

However, our ADS holders in the United States are not entitled to exercise or sell suchpre-emptive subscription rights related to the ordinary shares, which they represent unless we register thepre-emptive subscription rights and the securities to which thepre-emptive subscription rights relate under the Securities Act or an exemption from the registration requirements is available. In addition, the deposit agreement provides that the depositary will not make rights available to ADS holders unless the distribution to ADS holders or both the rights and any related securities are either registered under the Securities Act or exempted from registration under the Securities Act. Further, if we offer holders of our ordinary shares the option to receive dividends in either cash or shares, under the deposit agreement the depositary may require satisfactory assurances from us that extending the offer to holders of ADSs does not require registration of any securities under the Securities Act before making the option available to holders of ADSs. We are under no obligation to file a registration statement with respect to any such rights or securities or to endeavor to cause such a registration statement to be declared effective. Moreover, we may not be able to establish an exemption from registration under the Securities Act. Accordingly, ADS holders may be unable to participate in our rights offerings or to elect to receive dividends in shares and may experience dilution in their holdings. In addition, if the depositary is unable to sell rights that are not exercised or not distributed or if the sale is not lawful or reasonably practicable, it will allow the rights to lapse, in which case our shareholders and ADS holders will receive no value for these rights.

Item 4Information on the Company

We were organized under the laws of the Kingdom of Denmark in September 2006 as a private limited liability company (Anpartsselskab, or ApS) and then transformed into a public limited liability company (Aktieselskab, or A/S), effective December 17, 2007. In connection with this conversion, our legal name changed from Ascendis Pharma ApS to Ascendis Pharma A/S. We commenced operations in December 2007 in connection with the acquisition of the company that invented our TransCon technology,technologies, Complex Biosystems GmbH.

Our registered office and principal executive offices are located at Tuborg Boulevard 5,12,DK-2900 Hellerup, Denmark and our telephone number is +45 70 22 22 44. Our agent for service of process in the United States is Ascendis Pharma, Inc. Our website address is www.ascendispharma.com. The information on, or that can be accessed through, our website is not part of and should not be incorporated by reference into this this annual report or any other report we file or furnish to the SEC. We have included our website address as an inactive textual reference only. Our ADSs are traded on The NASDAQNasdaq Global Select Market under the symbol ASND.

The SEC maintains an internet site at www.sec.gov that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC.

For additional information relating to the development of our company, see “Item 4 B. Information on the Company – Business Overview.” For additional information relating to the Company’s capital expenditures, see “Item 5 A. Operating Results.”

Overview

We are a biopharmaceutical company applying our innovative TransCon technologytechnologies to build a leading, fully integrated rare disease company. We are developingbiopharmaceutical company and develop a pipeline of prodrug therapiesproduct candidates with potentialbest-in-class profiles to address significant unmet medical needs. We have created a portfolio of potentialbest-in-class rare disease endocrinology product candidates to address unmet medical needs by utilizing our TransCon technologytechnologies with clinically validated parent drugs. We currently have three product candidates in clinical development in rare endocrine diseases and we are working to apply our TransCon technology platform in additional therapeutic areas, including oncology. Additionally, we have developed a pipeline of sustained-release prodrug product candidates through strategic collaborations and we are working with these collaboration partners in the areas of ophthalmology and diabetes.

Our most advanced product candidate, TransCon Growth Hormone, or TransCon GH,hGH, is in development as a once-weekly therapylong acting prodrug of recombinant human growth hormone, also referred to treatas hGH, as a potential treatment for growth hormone deficiency, or GHD,GHD. On March 4, 2019, we announcedtop-line results from the heiGHt Trial. We are also conducting two additional trials with TransCon hGH, the fliGHt Trial, which evaluates TransCon hGH in pediatric subjects previously treated with daily hGH, and other indications.the enliGHten Trial, which evaluates long-term safety of TransCon hGH in subjects from both the heiGHt and fliGHt Trials. In JanuarySeptember 2018, we completed enrollment in the pivotal Phase 3fliGHt Trial, an open-label trial ofevaluating TransCon GH, the global heiGHt Trial,hGH in childrenpediatric subjects with GHD. We anticipatetop-line dataGHD who switched from the ongoing heiGHt Trialdaily hGH therapy. As a result, more than 300 subjects have now enrolled in the first quarter of 2019.phase 3 TransCon hGH program, which includes the heiGHt, fliGHt and enliGHten Trials. We believe that TransCon GHhGH may offer a once-weekly therapy for pediatric GHD with comparable safety, efficacy and tolerability asthe potential to improve outcomes compared to currently approved daily recombinant human growth hormone, known as rhGHhGH. We expect a clinical database lock for the TransCon hGH phase 3 program in pediatric GHD during the third quarter of 2019. Subsequently, we intend to submit a Biologics License Application, or GH. Clinical trialsBLA, to the U.S. Food and Drug Administration, or the FDA, for TransCon hGH to treat pediatric GHD in the first half of TransCon GH2020. We have demonstratedalso conducted a comparable efficacy, safety, tolerability and immunogenic profile tophase 2 clinical trial in adult subjects with GHD that will form the basis of daily growth hormone.designing future clinical research in adult GHD. If approved, TransCon GHhGH may reduce the burden of daily treatment by requiring significantly fewer injections, which may improve compliance and treatment outcomes.

We are also using our TransCon technology platform to develop TransCon PTH, which is designed as a once-daily long-acting injectable prodrug of parathyroid hormone, or PTH, as a potential treatment for hypoparathyroidism, or HP, a rare endocrine disorder of calcium and phosphate metabolism. We initiatedcompleted a Phasephase 1 trial in healthy subjects in September 2017 andMay 2018, the results from the ongoing study have reinforced findings fromof which were consistent with our preclinical research supporting the target product profile for TransCon PTH as a true replacement therapy. In this candidate.trial, TransCon PTH showed the predicted pharmacokinetic and pharmacodynamic response, suggesting the ability to normalize serum and urinary calcium levels in patients with hypoparathyroidism. We believe our TransCon PTH may provide patients suffering from HPhypoparathyroidism with a PTH replacement therapy that is designed to fully address all aspects of the disease more than standard of care or currently approved therapies. In June 2018, we were granted Orphan Drug Designation, or ODD, by the FDA for TransCon PTH. ODD is provided to drugs that are intended for the safe and effective treatment, diagnosis, or prevention of rare diseases or disorders that affect fewer than 200,000 people in the United States. We initiated the phase 2 trial in adult subjects with hypoparathyroidism in the first quarter of 2019 with the goal of evaluating different fixed doses of TransCon PTH and a titration regimen for complete withdrawal of standard of care (i.e., calcium and active Vitamin D supplementation), using aready-to-use prefilled pen device. Our plan for our phase 3 program for TransCon PTH includes incorporating trial sites in the United States, Europe, Australia, Canada, Japan and possibly other Asian countries.

We are also developing TransCon CNP, a long-acting prodrug ofC-type natriuretic peptide, as a potential therapeutic option for the treatment of achondroplasia, the most common form of dwarfism. Currently, there are no medical therapies for achondroplasia approved by the U.S. Food and Drug Administration, or FDA. TransCon CNP utilizes our TransCon technology platform to delivercreate a long-actingC-type natriuretic peptide, or CNP, analogueprodrug as a potential therapeutic option for potential treatment of achondroplasia.achondroplasia and potentially other skeletal disorders. CNP as a therapeutic approach is supported by extensive preclinical and clinical data. In December 2017,November 2018, we initiated regulatory filings in Australia to supportreported preliminary results from a Phasephase 1 clinical trial in healthy subjects.adult subjects, which supported our target product profile for TransCon CNP. In February 2019, we were granted ODD by the FDA for TransCon CNP. Our goal is to develop TransCon CNP as a safe and effective therapeutic option for achondroplasia and potentially other related growth disorders.

In addition to our wholly ownedpipeline of candidates in rare endocrine disorders, in January 2019, we announced that we are establishing oncology as our second independent therapeutic area of focus for our TransCon technologies. Our goal is to improve treatment efficacy while limiting or reducing toxicity by applying TransCon technologies to clinically validated drugs, using our unique algorithm for product innovation. We are conducting preclinical studies within the field of oncology to explore multiple potential product candidates and evaluate systemic as well as localized delivery systems using our TransCon platform.

In November 2018, we announced the formation of VISEN Pharmaceuticals, or Visen, a company established to develop and commercialize our endocrinology rare disease therapies in the People’s Republic of China, Hong Kong, Macau and Taiwan, or Greater China. In connection with the formation of Visen, we granted Visen exclusive rights to develop and commercialize certain product candidates based on our proprietary TransCon technologies, including TransCon hGH, TransCon PTH and TransCon CNP, in Greater China for use in all human indications, subject to certain exceptions. As consideration for the rights granted to Visen, we received 50% ownership in the outstanding shares of Visen and concurrently with the rights we granted to Visen, entities affiliated with Vivo Capital and Sofinnova Ventures purchased shares in Visen for an aggregate purchase price of $40 million in cash. We believe Visen supports our strategy to extend our endocrinology rare disease portfolio globally and establish a presence in China in partnership with collaborators who have significant experience and knowledge of the biopharmaceutical opportunity in China. In part because Visen was established in China, we believe Visen will be able to effectively develop and, if approved, market our innovative technologies to address the needs of the local markets in Greater China.

In addition, we have developed a pipeline of sustained release prodrug product candidates through strategic collaborations. These includecollaborations for TransCon anti-VEGF in the field of ophthalmology, which is partnered with Genentech, and the TransCon peptide program for the treatment of diabetes, which is partnered with Sanofi. We are eligible to receive up to an aggregate of €200 million in development and regulatory milestone payments for products currently being developed under our collaboration agreements, as well as sales-based milestone payments and royalties on future net sales of products.

We believe that the effectiveness of our TransCon technologytechnologies is supported by data from our preclinical research and the ongoing clinical programs, including our TransCon GHhGH, TransCon PTH and TransCon PTHCNP programs, as well as findings from our ongoing development of other product candidates, including our multi-product collaborations with Sanofi and Genentech. We have applied the TransCon technologytechnologies in combination with parent drugs with clinical proof of concept using our algorithm for creating products with the potential to bebest-in-class in endocrinology rare diseases, and we will continue to apply this algorthimalgorithm for product selection in new therapeutic areas. We believe this approach may reduce the risks associated with traditional drug development.

Our TransCon technology enablestechnologies enable us to create long-acting prodrug therapies with potentially significant advantages over existing marketed drug products. Our TransCon technologytechnologies transiently linkslink an unmodified parent drug to a TransCon carrier via our proprietary TransCon linkers. Our TransCon linkers predictably release an unmodified active parent drug at predetermined rates governed by physiological pH and temperature conditions, supporting administration frequencies from daily up to half-yearly.more than every six months. Depending upon the type of TransCon carrier we employ, we can design our TransCon prodrugs to act systemically or locally in areas that are difficult to treat with conventional therapies.

TransCon Product Candidate Pipeline

In addition to our pipeline of product candidates noted in the figure above, we are conducting preclinical studies in the field of oncology to explore multiple potential product candidates and evaluate systemic as well as localized delivery systems using our TransCon technologies.

When we apply our TransCon technologytechnologies to already approved drug compounds, we may benefit from established clinical safety and efficacy data, which we believe reducesincreases the probability of success compared to traditional drug development risk.development.

We maintain an intellectual property portfolio comprising approximately 103136 issued patents and approximately 203283 patent applications as of December 31, 2017,2018 with claims directed to composition of matter, process, formulation and/ormethods-of-use for our product candidates, including a product-specific device and core TransCon technology.technologies. In addition, each of our collaboration partners hasGenentech and Sanofi have granted us rights that enable us to freely commercialize all improvements to the TransCon technologytechnologies developed by oursuch collaboration partners outside of the field identified in their respective collaboration agreements. WeOther than the rights we have granted to Visen, Sanofi, and Genentech as described herein, we hold worldwide rights to our TransCon technologytechnologies and haveowe no third-party royalty or milestone payment obligations with respect to our TransCon technologytechnologies or any of our product candidates. While our TransCon prodrugs may incorporate already approved parent drugs, each of our product candidates is a new molecular entity and is therefore eligible to be granted new intellectual property rights, including new composition of matter patents.

Our Strategy

Our goal is to leveragebuild a fully integrated biopharmaceutical company by applying our TransCon technology platforms to create a pipeline of proprietary products and form collaborations with market-leading biopharmaceutical companies to develop new products that incorporate our TransCon technology in therapeutic areas that are of strategic importance.products. Our approach tounique algorithm for product innovation involves a focusfocuses on orphan drugidentifying indications that have an unmet medical need, have a clinically validated parent drug, are suitable to our TransCon Technology,technologies, have a clearly differentiated product, have a potential established development pathway and have a large potentially addressable market. Additionally, we form collaborations with market-leading biopharmaceutical companies to develop new products that incorporate our TransCon technologies in therapeutic areas that are of strategic importance.

Using this approach for our endocrinology rare disease franchise, we have obtained positive clinical data for all three of our TransCon product candidates. We estimate thatare working towards regulatory approval of these candidates in three high value indications, and we are exploring label expansion opportunities, as there are approximately 4,800 orphan drug designations and over 500 of those are for endocrine and metabolic disorders. We expect our currentnear-term therapeutic focus on our rare disease endocrinology pipeline will provide important synergies and a strong foundation for building our commercial infrastructure, including expertise in endocrinology, a concentrated prescriber base, a patient-centric support system, reimbursement and payor knowledgeexpertise and distribution networks.

For the longer term, our aim is to utilize our product innovation algorithm to advance into new therapeutic areas and create sustainable growth through multiple approaches.

In January 2019, we introduced Vision 3x3, our strategic roadmap through 2025 to achieve sustainable growth. Key elements of our strategy to achieve this goal include:Vision 3x3 include to:

TransCon TechnologyTechnologies

Overview

Our TransCon technology istechnologies are designed to solve the fundamental limitations of previous approaches applied to extend duration of a drug’s action in the body, and to enhance the overall benefit of a given therapeutic. Many drugs suffer from suboptimal pharmacokinetics, short residence time in the body, poor tolerability at the administration site and/or systemic side effects that result from initial drug concentrations that are too high. Frequent administration and poor tolerability negatively impact patient compliance, potentially leading to suboptimal treatment outcomes. To address these issues, several approaches are currently being applied to improve drug characteristics, such as prodrug and sustained release technologies.

Our TransCon technology establishes a new paradigm that combinestechnologies combine the benefits of conventional prodrug and sustained release technologies and is broadly applicable to proteins, peptides and small molecules. TransCon prodrugs predictably release unmodified active parent drugs and may offer advantages that include superiorcreate new therapies with potentially optimized therapeutic effect, including efficacy, safety tolerability and compliance, including less frequent dosing andfrequency. We believe the abilitytechnologies can be applied broadly to switch patients to subcutaneous injections from burdensome continuous infusions and less frequent dosing.

Oura protein, peptide or small molecule in multiple therapeutic areas. TransCon technology is differentiated in that it enables us to design long-acting prodrugs that predictably releasemolecules have three components: an unmodified active parent drug. Our TransCon linkers predictably release an unmodified activeexisting parent drug, at predetermined rates following first order kinetics, governed by physiologicalan inert carrier that protects it, and a linker that temporarily binds the two. When bound, the carrier inactivates and shields the parent drug from clearance. When injected into the body, physiologic pH and temperature conditions. By optimizingconditions initiate the molecular structurerelease of the linker, administration frequencies from daily up to half-yearly can be achieved. TransCon prodrugs may offer safety, efficacy and tolerability advantages over the originalactive, unmodified parent drug and as comparedin a predictable release manner. Because the parent drug is unmodified, its original mode of action is expected to other technologies used to extend drug residence time in the body.be maintained. Depending upon the type of TransCon carrier we employ, we can design our TransCon prodrugs to act systemically or locally in areas that are difficult to treat with conventional therapies. In addition to retaining the original mode of action of the unmodified parent drug, we believe this predictable release may improve the likelihood of clinical development success. We refer to our systemic and localized applications of TransCon as individual technologies.

Advantages of our TransCon TechnologyTechnologies

We believe that our TransCon technology enablestechnologies enable multiple therapeutic, drug development, regulatory and intellectual property benefits:

Efficacy

Safety and Tolerability

Development and Regulatory

Intellectual Property

TransCon Technology Components

Our TransCon prodrug product candidates consist of three components: the TransCon carrier,linker, the TransCon linkercarrier and a parent drug.

Our TransCon carriers can be selected from our soluble or hydrogel carrier platforms. These carriers inactivate and protect the parent drug through a shielding effect, which prevents rapid excretion and degradation of the parent drug. The parent drug is connected to the carrier via the TransCon linker, which is designed to release the drug at a predictable and predetermined rate, enabling release of unmodified active parent drug with up to half-yearly administration. The TransCon linker is designed to remain attached to the TransCon carrier after release of the parent drug. Our broad selection of TransCon linkers, in combination with our solublesystemic and hydrogellocalized carriers, provides us with a powerful and flexible technology platform that we leverage to design potentiallybest-in-class therapeutics aimed at multi-billion dollar markets. The following illustration depicts how the TransCon technology transforms a parent drug into a prodrug:to address unmet medical needs.

TransCon Linkers

Our TransCon linkers are reversible linkers that enable the transient conjugation of a broad range of therapeutics, including proteins, peptides and small molecules, to our TransCon carriers. We have a large library of TransCon linkers that are applicable to various types of parent drugs, and that can be tailored to achieve half-life extension enabling daily, weekly, monthly and half-yearly dosing, and customize the pharmacokinetic, or PK, profile for each individual product candidate to optimize therapeutic effect. TransCon linkers are self-cleaving through a process

called intra-molecular assisted cleavage, which causes the linker to release the unmodified parent drug. We can tailor the release properties of the linker to a given therapeutic indication and parent drug by modifying the linker structures. We believe the self-cleaving process of our linker avoids many of the shortcomings of conventional prodrug technologies, which often depend on metabolic processes, such as enzymatic degradation, to convert the prodrug into the active drug. The rate of metabolic conversion of prodrugs in these types of processes may differ between patients, and even within different tissues in the same patient. As a result, conventional prodrugs do not offer predictable release of the parent drug. Our TransCon linkers predictably release an unmodified active parent drug at predetermined rates governed by physiological pH and temperature conditions, which are tightly regulated in the body. Consequently, we can design our prodrugs to release the unmodified parent drug at predictable rates.

TransCon Carriers

Our TransCon technology incorporatestechnologies incorporate two carrier platforms that can be used for providing localized or systemic drug exposure. These biocompatible carrier platforms include our TransCon solublesystemic carriers and our proprietary TransCon hydrogellocalized carriers, which is aare self-eliminating hydrogel.hydrogels. Our carriers inactivate and protect the drug through a shielding effect, which prevents rapid excretion and degradation of the parent drug and may enable benefits that include improved injection site tolerability, reduced systemic adverse effects and low immunogenicity.

Parent drugDrug

Our TransCon technology istechnologies are applicable across a broad range of therapeutic classes and is currently used to create superior long-acting product candidates based on proteins, peptides and small molecules. By primarily focusing on biological targets that have been clinically validated, we can leverage available knowledge regarding a target’s activity. Based on this selective approach, we know what drug levels must be maintained in the body for optimal efficacy and safety, and we can design the release half-life and dosing frequency of our TransCon prodrugs to maintain these levels to achieve the desired pharmacological effect. We move a product candidate into development after it demonstrates a superior profile to such medicines or drugs in animal models that we believe correlate to human clinical experience. Furthermore, based on the established translational relationships between preclinical animal models and clinical efficacy, we believe experimental results generated in validated animal models are highly predictive of clinical results and reduce the development risk of our TransCon prodrugs. This strategy is designed to reduce risk and increase productivity.

This approach has enabled us to generate a pipeline of product candidates to address significant unmet medical needs and to become potential sources of significant revenue for our company. Because our TransCon technology releasestechnologies release an unmodified drug with established clinical safety and efficacy, we believe we may benefit from a higher development and regulatory success rate as compared to development of drug compounds without established clinical data.

TransCon Product Candidates

TransCon Growth Hormone (GH)(hGH)

Market Opportunity in GHD

GHD is a serious orphan disease that affects both children and adults. Children with GHD are characterized by short stature, metabolic abnormalities, cognitive deficiencies and poor quality of life. GHD in adults is associated with increased adiposity, or fat mass, as well as psychiatric-cognitive, cardiovascular, muscular, metabolic and skeletal abnormalities. The current standard of care for GHD is daily subcutaneous injections of GH.hGH. Daily therapy with GHhGH has been shown to increase growth and improve metabolic effects, including reducing adiposity and improving cardiovascular health. These therapies have been shown to be safe well-tolerated and essentially pain-free upon injection.well-tolerated.

Patients treated with daily GH typically receive thousands of injections over the course of many years. Growth hormone deficienthormone-deficient children who are fully in adherence with their daily treatment regimen may achieve a height in adulthood that is comparable to that of their family members and national norms. In therapy-compliant adults with GHD, daily subcutaneous injections of GHhGH have resulted in improved body composition parameters, bone density, cardiovascular outcomes and quality of life.

Despite the demonstrated benefits of GHhGH therapy, publishedcompliance continues to be a challenge, as patients treated with daily hGH typically receive thousands of injections over the course of many years. Published studies have shown that the majority of patients on a daily GHhGH regimen are not fully compliant with their daily dosing schedule, and therefore fail to achieve expected treatment outcomes. For example, inIn a 2011 study published in PLOS One, in 2011, 66% of the patients missed more than one injection on average per week, leading towhich resulted in significant reductions in the degree of growth in pediatricthose patients. For caregivers of young children and teenagers who likely have had to endure daily injections of hGH for many years, the problem of needle fatigue – missing injections because of the pain, bruising or other effects of daily treatment – remains an important reason for noncompliance with daily treatment.

Reducing injection frequency is associated with better compliance and may improve height velocity (HV) for patients experiencing poor compliance with daily injections.

As shown in the figure below, for patients missing two or more injections per week, there was a clinically relevant reduction in their change in height velocityHV standard deviation score, or HVSDS, compared to high-compliance patients. A greater HVSDS indicates more rapid growth:

Figure 1. Negative impact of poor compliance on growth response. Patients missing two or more injections per week have a statistically significant reduction in height velocity. A result is considered statistically significant when thep-value, representing the probability that random chance could explain the result, is lower than 0.05.(Cutfield et al, 2011.)

Since the introduction of GHhGH in 1981, many of the world’s largest pharmaceutical companies have developed and now market daily growth hormonehGH products. All currently marketed GHhGH products in the United States, Norditropin^® (Novo Nordisk A/S), Humatrope^® (Eli Lilly and Company), Nutropin AQ^® (Genentech), Genotropin^® (Pfizer Inc.), Saizen^® (Merck Serono S.A.), Zomacton^® (Ferring Pharmaceuticals, Inc.) and Omnitrope^® (Sandoz GmbH), contain unmodified GHhGH and are administered by daily subcutaneous injections. The global market for daily GHhGH products is dominated by Novo Nordisk, Pfizer, Eli Lilly, Sandoz, Merck KGaA and Roche, which together account for approximately 95% of global market share.

Primary indications for GHhGH in children are GHD, idiopathic short stature, chronic kidney disease, Prader-Willi syndrome, small for gestational age and Turner syndrome. In adults, primary indications for GHhGH include GHD and AIDS-induced weight loss. Pediatric indications comprise up to 90% of the total GHhGH market, of which approximately half is for GHD.

Global annual sales from currently marketed daily GHhGH injections are estimated at $3.5 billion in 2014. We believe a significant market opportunity exists for a long-acting version of GHhGH with comparable efficacy, safety and tolerability as daily growth hormonehGH products. We are developing TransCon GHhGH as a once-weekly therapy with a target profile designed to have comparable efficacy, safety and tolerability to daily GH.hGH, but with a dosing regimen that could improve adherence and overall health.

Competitive Landscape for Long-Acting Growth Hormone

Since the 1990s, the pharmaceutical industry has employed various approaches to develop long-acting growth hormonehGH products to reduce the patient burden of daily injections and increase patient compliance with the dosing regimen. To date, regulatory authorities have approved only two long-acting growth hormone products, each of which utilize unmodified growth hormone as the active drug substance. Neither of these products has achieved commercial success, due to manufacturing, regulatory, efficacy, safety and/or tolerability reasons.

Approaches to developing a long-acting GH or GH analogs use technologies thatThese approaches generally fall into two categories: encapsulation and permanent GH modification:hGH modification:

Previous attempts to develop a long-acting GH by utilizing permanent modification of growth hormone have failed due to regulatory, safety, efficacy and manufacturing hurdles.

There are currently no long-acting growth hormone treatment options available in the United States or Europe. A permanently PEGylated long-acting growth hormone developed by GeneScience Pharmaceuticals Co., Ltd. is available in China and the Somatropin Biopartners product (LB03002), is available in Korea. Genexine Inc., JCR PharmaceuticalsHanmi Pharmaceutical Co., Ltd., Bolder Biotechnology, Novo Nordisk A/S, and OPKO Health, Inc., are developing long-acting growth hormone analogs based on the permanent modification of growth hormone.

In addition to the currently approved and marketed daily growth hormone therapies, there are a variety of experimental growth hormone therapies in different stages of clinical development by various companies, including Bioton S.A.GeneScience Pharmaceuticals Co., CriticalLtd., Genexine Inc., JCR Pharmaceuticals Co., Ltd.,Dong-A Pharmaceutical, Novo Nordisk A/S, and all of theOPKO Health, Inc. (in collaboration with Pfizer Inc.) and other global and regional pharmaceutical companies with existing growth hormone franchises.

Our Solution: TransCon GHhGH

TransCon GHhGH is a novel long-acting prodruggrowth hormone product candidate that is being developed for the treatment of GH thatGHD. It is designed to maintain the same mode of action as daily therapies. Clinical studiestherapies by releasing the same growth hormone molecule as daily therapy. TransCon hGH is composed of TransCon GH have demonstrated an efficacy, safety, tolerability and immunogenic profileunmodified growth hormone that is comparabletransiently bound to that of daily growth hormone. TransCon GH addresses the highest priority unmet medical need in growth hormone therapy by reducing the number of injections patients require, while leveraging the over 30 year history of safetya carrier and efficacy that has been established with unmodified daily GH products.proprietary linker.

TransCon GHhGH is essentially inactive when administered. Our technology istechnologies are designed to restore full activity of the parent growth hormone when the unmodified growth hormone is released from the prodrug. The TransCon linker releases the unmodified growthreleased. Growth hormone at a predictable releaseis predictably released, enabling weekly dosing. We have conducted biopotency assays and generated mass spectrometry profiles demonstrating that the bioactivity and structure of growth hormone released from TransCon GHhGH is comparable to the growth hormone in marketed growth hormone products administered as daily injections. As such,Importantly, we expect our once-weekly TransCon GHhGH to have the same mode of action and distribution into key growth hormone-responsivehormone -responsive tissues, such as brain, bone, muscle, liver and fat tissue, as the GHhGH administered from daily injections and endogenous growth hormone. We use daily growth hormone as an active comparator in our clinical studies, allowing us to directly compare the activity of TransCon GHhGH to daily growth hormone in an identical clinical setting.

TransCon hGH is designed to address the highest priority unmet medical need in growth hormone therapy by reducing the number of injections patients require, while leveraging the over30-year history of safety and efficacy that has been established with unmodified daily growth hormone products.

Clinical Development of TransCon GHhGH for Pediatric GHD

Our TransCon GH product candidate is in Phase 3 developmentIn March 2019, we reportedtop-line results for pediatric GHD. In January 2018, we completed enrollment of the global Phase 3 TransCon GH heiGHt Trial, in children with GHD. The heiGHt Trial is a randomized, open-label, active-controlled Phase 3 registration trialwhich TransCon hGH was observed to have superior efficacy and comparable safety and tolerability to that has enrolled 161 children with GHD who have not previously been treated. Subjects receive either once-weekly TransCon GH (0.24 mg/kg/week) orof daily injections of Genotropin^® at 34 µg/kg/day (0.24 mg/kg/week) with a 2:1 randomization. The primary endpoint of the trial is annualized height velocity after 52 weeks of treatment. The primary statistical analysis will be anon-inferiority analysis comparing the two arms. Other key endpoints include annualized height velocity at earlier time points, change in height standard deviation scores over 52 weeks, change in serum insulin-like growth factor I(IGF-1) and insulin-like growth factor-binding protein 3(IGFBP-3) levels, change inIGF-1 standard deviation scores andIGFBP-3 standard deviation scores, and normalization ofIGF-1 standard deviation scores.Top-line results are anticipated in the first quarter of 2019 and wehGH. We expect our efficacy and safety database lock for our regulatory filings with the FDA and European Medicines AgencyEMA to occur in the third quarter of 2019. We subsequently intend to submit a Biologics License Application (BLA) to the U.S. Food and Drug Administration (FDA) for TransCon hGH to treat pediatric GHD in the first half of 2020.

In October 2017, we initiated an additional Phasephase 3 trial, the fliGHt (switch) Trial, which is designed to evaluate TransCon GHhGH in subjects who have been previously treated with daily GH.growth hormone. In this single arm open-label trial, subjects would switch from daily growth hormone therapy to weekly TransCon GHhGH with a primary objective of determining the safety and tolerability of TransCon GHhGH in subjects with pediatric GHD. At the request of the FDA to evaluate TransCon GHhGH in children younger than three years, we may also enrollenrolled subjects younger than three years of age who may betreatment-naïve. We planenrolled a total of 146 subjects, completing enrollment in September 2018. We expect to enroll approximately 150 subjects and complete enrollment byreporttop-line data for the thirdfliGHt Trial in the second quarter of 2018.2019.

Subjects completing either the heiGHt or fliGHt Trials may also enroll in an open-label extension study, the enliGHten Trial, in which we expect the vast majority of subjects finishing the heiGHt and fliGHt Trials to enroll. The enliGHten Trial is designed to provide long-term safety data in approximately 300 subjects to support the potential future regulatory filings for TransCon GH.hGH. We initiated the enliGHten Trial in 2017 as the first subjects began to roll over from the heiGHt Trial.

Top-lineResults from the Phase 2 trial3 heiGHt Trial in pediatric subjectsPediatric Subjects with GHD

We haveThe heiGHt Trial was a randomized, open-label, active-controlled phase 3 registrational trial that enrolled 161 children with GHD who had not previously conductedbeen treated. Subjects received either once-weekly TransCon hGH (0.24 mg/kg/week) or daily injections of Genotropin^® at 34 µg/kg/day (0.24 mg/kg/week) with a 2:1 randomization. The primary endpoint was annualized height velocity (AHV) at 52 weeks, with anon-inferiority analysis comparing the difference between the two treatment groups. Other key endpoints included AHV at earlier time points, change in height standard deviation scores (SDS) over 52 weeks, change in serum insulin-like growth factor I(IGF-1) and insulin-like growth factor-binding protein 3(IGFBP-3) levels, change inIGF-1 standard deviation scores andIGFBP-3 standard deviation scores and normalization ofIGF-1 standard deviation scores. Two subjects, one from each arm, withdrew from the trial prior to the final visit.

Top-line results showed that once-weekly TransCon hGH was superior to once-daily hGH on the primary endpoint of AHV at 52 weeks. In the primary analysis of theintent-to-treat population using ANCOVA, TransCon hGH was associated with an AHV of 11.2 cm/year compared to 10.3 cm/year for the daily hGH. The treatment difference was 0.86 cm/year with a 95 percent confidence interval of 0.22 to 1.50 cm/year. The AHV for TransCon hGH was significantly greater than the daily hGH (p=0.0088).

The AHV was greater for TransCon hGH than for the daily hGH at each visit, with the treatment difference reaching statistical significance from and including week 26 onward. The incidence of poor responders (AHV < 8.0 cm/year) was 4 percent and 11 percent in the TransCon hGH and daily hGH arms, respectively. All sensitivity analyses completed from the trial support the primary outcome, indicating the robustness of these results.

Results from the trial indicate that TransCon hGH was generally safe and well-tolerated, with adverse events consistent with the type and frequency observed with daily hGH therapy and comparable between arms of the trial. No serious adverse events related to study drug were observed in either arm. No treatment-emergent adverse events leading to discontinuation of study drug were observed in either arm.

Additional Preliminary Analyses from the heiGHt Trial:

The results presented for the heiGHt Trial are consistent with findings from the phase 2 trial, an active-controlled Phase 2 trial which found that demonstrated TransCon GHhGH was comparable to daily GHhGH in 53treatment-naïve,pre-pubertal children with GHD. The Phasephase 2 trial was designed to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics and efficacy of TransCon GH.hGH. This6-month multi-center, randomized, open-label trial compared three dose levels of TransCon GHhGH (0.14; 0.21; and 0.30 mg GH/kg/week), administered once per week, to Genotropin at 30 µg/kg/day (0.21 mg GH/kg/week), administered as a daily injection. The primary efficacy endpoint was annualized mean height velocity at six months.

Mean annualized height velocities among the three dosing levels administered weekly were 11.9 cm for the 0.14 mg/kg/week dose, 12.9 cm for the 0.21 mg/kg/week dose, and 13.9 cm for the 0.30 mg/kg/week dose, which were comparable to 11.6 cm for the active comparator, daily injections of Genotropin at a 0.21 mg/kg/week dose.

Figure 2. Annualizedsix-month height velocity (N=53) of three dose-levels of TransCon GH administered once per week (at doses of 0.14, 0.21 and 0.30 mg GH/kg/week), against an active control group comprising Genotropin^® (0.21 mg GH/kg/week), administered as injections once per day (0.03 mg GH/kg/day) for seven days.Proprietary Auto-injector Development

The Phase 2 pediatric trial profiledIGF-1 levels, the primary biomarker forAs part of our effort to improve treatment compliance among children with GHD, during week 13. This profile demonstrated dose-proportionality inIGF-1 levels between the three TransCon GH doses. The normal range forIGF-1 in children varies with age, soIGF-1 levels are expressed asIGF-1 standard deviation scores, orIGF-1 SDS, which enables the comparison ofIGF-1 responses for children across age ranges. The normal range is defined asIGF-1 SDS between-2 and +2 SDS. The meanIGF-1 response for all TransCon GH dose levels were maintained in the normal range. Transient point values ofIGF-1 SDS > +2 were observed in a small number of subjects and only in the high-dose treatment arm. These results are consistent with published data evaluating the effects of comparable doses of daily GH onIGF-1. There were no reports of safety issues in connection with these transient elevations.

Figure 3.IGF-1 profiles during Week 13 following weekly subcutaneous administration of TransCon GH (at doses of 0.14 mg, 0.21 mg and 0.30 mg GH/kg/week). Dose dependentIGF-1 response observed. Error bars +Standard Error of the Mean.

The Phase 2 pediatric trial measured blood levels of GH released from TransCon GH and daily GH during week 13. Consistent with previous clinical studies of TransCon GH, this profile demonstrated a dose-proportional increase in unmodified growth hormone following administration of the three dose levels of TransCon GH, and, as illustrated in Figure 4, the maximum blood concentration of unmodified GH released from TransCon GH was comparable to the levels achieved by the corresponding amount of GH given as daily injections.

Figure 4. GH profiles during Week 13 following weekly subcutaneous administration of TransCon GH (0.21 mg GH/kg/week) or daily subcutaneous administration of Genotropin (30 µg/kg/day). Error bars +Standard Error of the Mean

There were over 1,100 TransCon GH injections in our Phase 2 pediatric trial and the safety of TransCon GH was comparable to Genotropin. There was one reported case of an inguinal hernia, which was deemed unlikely to be related to the study drug, and there were no other reports of serious or unexpected adverse events. The adverse events observed were consistent with daily GH therapy and not different between cohorts. Injection site reactions were generally mild and transient and we observed no incidences of injection site nodule formation or lipoatrophy. TransCon GH showed low immunogenicity comparable to levels reported for daily GH therapies, with no neutralizing antibodies.

In addition, we are developing astate-of-the-art auto-injector for the administration of TransCon GH that is designedhGH. We are planning to beeasy-to-useintroduce this in the pediatric populationenliGHten Trial in the second quarter of 2019 and leverages proven technologies.to make it available to patients in conjunction with a potential commercial launch. Theeasy-to-use device has a single,low-volume injection for mostthe majority of patients of less than 0.6 mL and requires a small,31-gauge needle that is 31 gauge, fouronly 4 millimeters in length, andwhich is comparable to needles used to administer daily GH. Furthermore thehGH. The device provides for room temperature storage, includes anempty-all design and is expected to last for at least four years and will be enabled for Bluetooth connectivity.years. We have conducted human factor studies in overmore than 100 subjects and incorporated the findings into ourthe design of theour auto-injector. We are also working on strategies that will enable the auto-injector to integrate with the digital healthcare system, including Bluetooth connectivity features and an abilityto allow for automated data capture. We expecteasy tracking of dosing compliance over time.

Figure 2. Ourstate-of-the-art auto-injector is designed to introduce the auto-injector during our long-term extension trialimprove treatment compliance for TransCon GH, the enliGHten Trial, and to make it available to patients in conjunctionchildren with a potential commercial launch.GHD.

Clinical Development of TransCon GHhGH in Adults

We have previously conducted trials of TransCon GHhGH in adults and intend to pursue development of TransCon GHhGH in adult GHD. We have completed several Phasephase 1 trials in healthy adult subjects.

In September 2011, we reported data following the completion of a Phasephase 2, European, multi-center, multiple dose, open-label, active-controlled, study to examine the safety, tolerability, pharmacokinetics and pharmacodynamics in 37 adult male and female subjects with GHD.

In this study, serum levels of free GHhGH and TransCon GHhGH increased proportionally with the administered dose. The maximum serum concentration of GHhGH released from TransCon GHhGH was comparable to the levels achieved by the corresponding amount of GHhGH given as daily injections. The GHhGH profiles during Week 4 following weekly subcutaneous administration of TransCon GHhGH or daily subcutaneous administration of Omnitrope^® (0.006 mg hGH/kg/day, equivalent to 0.04 mg hGH/kg/week) demonstrated good dose proportionality between TransCon GHhGH dose groups, with peak serum concentrations of GHhGH being comparable between dose matched TransCon GHhGH and daily GHhGH (0.04 mg GH/kg/week).

TransCon GHhGH also elicited anIGF-1 response that was similar to theIGF-1 response of the same cumulative dose of GHhGH administered as daily injections over a week. Importantly, theIGF-1 response at Week 1 and Week 4 were similar and without significant accumulation.

In addition to demonstrating similar maximum GHhGH and resultingIGF-1 concentrations when administered at the same cumulative weekly dose, the exposure to GHhGH andIGF-1 over one week, as judged by AUC, orArea-Under-the-Curve, was similar between TransCon GHhGH and daily GH.hGH.

In this study, adverse events were comparable to the incidence and type generally expected when GHhGH is administered to adults with GHD. Only mild and transient injection site reactions were observed across all treatment groups with no difference between treatment groups, including daily GH.hGH.

No treatment-emergentanti-GH anti- hGH antibody formation was observed during this multiple-dose study. Importantly, we did not observe any injection site lipoatrophy following repeated injections of TransCon GH.hGH. We believe the PK and pharmacodynamics, or PD, data gathered in our Phasephase 2 multi-dose study in adult subjects supports the desired once-weekly dosing regimen and confirms the favorable safety profile of TransCon GHhGH previously observed in Phasephase 1 studies.

Future Development Plans

We are currently evaluating clinical development plans for TransCon GHhGH in adult GHD and additional pediatric indications, and we intend to initiate afollow-up clinical trialtrials in the future. We are also considering other potential indications for TransCon GHhGH where a long-acting GHhGH therapy may offer abest-in-class option for patients suffering with rare growth disorders.

We currently retain world-wide commercial rights to TransCon GH,hGH outside of rights granted to VISEN Pharmaceuticals in Greater China, and may consider forming strategic alliances, creating joint ventures or entering into licensing arrangements with third parties in key geographies where we believe a collaboration partner can aid in the development, regulatory approval and commercialization of TransCon GH.hGH.

TransCon PTH

Market Opportunity in Hypoparathyroidism

Hypoparathyroidism, (HP)or HP, is a rare endocrine disorder characterized by deficient or absent parathyroid hormone, (PTH)or PTH, affecting approximately 80,000 patients in the United States. The most common cause in approximately 75% of cases is inadvertent removal or damage to the parathyroid tissue during neck surgery. Patients with HP cannot adequately regulate calcium and phosphate metabolism and suffer from low calcium and elevated phosphate levels in the blood. The condition results in a diverse range of physical, cognitive and emotional symptoms, including psychiatric disorders, depression, basal ganglia calcifications, lenticular and arterial calcifications. Sustained hypocalcemia manifests clinically as perioral numbness, paresthesias, “brain fog,” and carpopedal muscle spasms, in addition to the serious and potentially life-threatening laryngeal spasm, tetany, and seizures.

PTH controls serum calcium via several mechanisms. PTH acts to release calcium from the skeleton and in the kidney to reabsorb calcium from the urine. In addition, PTH facilitates the conversion of 1,25 dihydroxyvitaminD-325 hydroxyvitamin D to the active form, which in turn acts on the intestines to increase calcium absorption. Through these primary pathways, calcium homeostasis is maintained.

Standard of care (SOC)(SoC) today for HP patients primarily consists of oral calcium and active vitamin D supplementation. However, since PTH is not present at the kidney to facilitate calcium reabsorption from the urine, the goal of SOCSoC is to maintain serum calcium (sCa) levels just below or within the lower part of the normal range(8.5-10.5 mg/dL, or2.125-2.625 mmol/L), and thereby limit as much as possible the damage from excess urinary calcium. Nonetheless, SOCSoC frequently leads to significant sCa fluctuations accompanied by symptomatic hyper- or hypocalcemia. In addition, SOC is associated with long-term complications such as worsened hypercalciuria and ectopic calcifications, the latter a consequence of an elevated calcium x phosphate product (CxP). SOCISOC with calcium and active vitamin D have been shown to contribute to the risk of renal disease.

HP also poses a high burden on the healthcare system despite current standard of care. For example, one survey of 374 patients showed that 72% experienced more than 10 symptoms in the preceding 12 months, with symptoms experienced for a mean of 13 ± 9 hours a day. Patients often experience decreased quality of life. Other studies showed that 79% of HP cases require hospitalizations and that patients with the disorder results have a four-fold increase in the risk of renal disease compared to healthy controls.

In 2015, Natpara,PTH(1-84), was approved for once-daily subcutaneous injection as an adjunct to vitamin D and calcium in patients with hypoparathyroidism. Natpara has not demonstrated an ability to reduce incidences of hypercalcemia, hypocalcemia or hypercalciuria relative to conventional therapy in treated patients. Teriparatide,PTH(1-34), approved since 2002 for the treatment of osteoporosis, has historicallysometimes been used for treatment of hypoparathyroidism using multiple daily injections, despite not being approved for this indication. Clinical research conducted by the NIH of subjects receiving continuous exposure toPTH(1-34), administered by an infusion pump, has demonstrated simultaneous normalization of sCa and urinary calcium, as well as normalization of bone turnover.

Our Solution: TransCon PTH

TransCon PTH is designed as a novel long-acting injectable prodrug ofreplacement therapy for parathyroid hormone, or PTH, dosed once-daily to achieve and maintain a steady concentration of PTH in the bloodstream within the normal range, at levels similar to those observed in healthy individuals. TransCon PTH is designed to restore physiologic levels of PTH 24 hours per day, thereby more fully addressing all aspects of the disease including normalizing serum and urinary calcium and serum phosphate levels. Pharmacokinetic data from the ongoing Phaseour phase 1 trial of TransCon PTH in healthy subjects demonstrated a half-life of approximately 60 hours, supporting an infusion-like profile with daily administration. This half-life is a substantial increase compared toPTH(1-34) andPTH(1-84), both of which after subcutaneous administration to humans have half-lives of only a few hours.hours after subcutaneous administration to humans.

With once-daily dosing, we believe this substantial half-life extension of PTH could reflect more closely reflect the physiological levels of PTH observed in healthy individuals and maintain blood calcium levels and normalize urinary calcium excretion, an improvement over what is currently feasible with existing approved therapies. Pharmacokinetic data from multiple ascending dose (MAD) cohorts in our ongoing Phasephase 1 trial of TransCon PTH in healthy subjects demonstrated an infusion-like profile. By providing steady levels of PTH in the physiological range, we believe TransCon PTH can address the fundamental limitations of short acting PTH molecules, such as Natpara, orPTH(1-84), and Forteo, orPTH(1-34) and become a highly differentiated therapy for HP.

Development of TransCon PTH

We have conducted extensive preclinical research to evaluate the PK and PD effects of TransCon PTH and establish the appropriate TransCon prodrug release kinetics and dosing regimen to deliver an infusion-like profile in rat and monkeys. These studies enabled us to model the effects of TransCon PTH in healthy adults in order to guide our clinical program.

In September 2017,May 2018, we initiatedcompleted a Phasephase 1 randomized, single and multiple ascending dose trial to evaluate the safety tolerability, pharmacodynamics and pharmacokinetics of TransCon PTH in healthy adults. Primary objectives of the trial include to assessincluded assessing the safety and tolerability of single and 10 multiple daily doses of TransCon PTH in healthy adults. Secondary objectives of this trial includes,included evaluation of pharmacodynamics, including serum calcium, down regulation of endogenousPTH(1-84), and bone markers; pharmacokinetics following single and multiple daily doses of TransCon PTH; assessment of whether TransCon PTH treatment effects urine calcium excretion;affects fractional excretion of urinary; and, incidence ofanti-PTH andanti-PEG antibodies.

Data from SAD and MAD cohorts of TransCon PTH led to sustained and dose-dependent elevations of serum calcium lasting more than 72 hours with low inter-subject variability. This dose-dependent response and low inter-subject variability suggests the ability to titrate and individualize dosing in patients. Following 10 repeated doses, free PTH exhibited a flat, infusion-like profile with low inter-patient variability. TransCon PTH was also demonstratedobserved to have the expected effects on renal calcium reabsorption based on fractional excretion and down regulation of endogenousPTH(1-84).

The desired profile observed in the SAD cohorts was confirmed in the MAD cohorts. Following 10 repeated doses, free PTH demonstrated a flat, influsion-like profile with very low inter-patient variability .

Figure 1: PK after 10TransCon PTH daily dosing for10 days of TransCon PTH 12, 16 and 20 µg per day (n=8)(n=7-8 per group). TransCon PTH daily dosing for 10 days provided a flat infusion-like profile with a low PTHpeak-to-trough ratio at day 10.

In addition, the TransCon PTH PK translated into a predictable sCa response, suggesting the ability to titrate patients with HP into the normal calcemic range, consistent with preclinical data.

Figure 2: Serum calcium over 10 days of TransCon PTH (n=8/group). TransCon PTH daily dosing for 10 days provided a dose-dependent increase of serum calcium.

TransCon PTH also demonstrated the expected effect on renal calcium reabsorption, and maintained a normal fractional excretion of calcium, even in the presence of hypercalcemia, predicting control of both serum and urine calcium.

Figure 3: Control of urinary calcium with a single dosemultiple doses of TransCon PTH 100 µg (n=8)8/group). Despite serum calcium at 11 mg/dL, fractional calcium excretion remained normal and below the 6.5% range reported for healthy subjects clamped to serum Ca of 10.3 mg/dL2,dL², reflecting potent renal calcium reabsorption.

We expect full data fromThe final results of the ongoing Phasephase 1 trial were consistent with our target product profile for TransCon PTH, showing the predicted pharmacokinetic and pharmacodynamic response, and suggesting the ability to normalize serum and urinary calcium levels in patients with hypoparathyroidism. We believe our TransCon PTH may provide patients suffering from hypoparathyroidism with a PTH replacement therapy that is designed to fully address all aspects of the disease more than standard of care or currently approved therapies.

In June 2018, we were granted Orphan Drug Designation, or ODD, by the FDA, for TransCon PTH. The FDA may designate a drug or biologic as an orphan drug if it is intended to treat a rare disease or condition, which is generally defined as a patient population of fewer than 200,000 individuals in the second quarterUnited States, or a patient population greater than 200,000 in the United States where there is no reasonable expectation that the cost of 2018. If our Phase 1developing the drug will be recovered from sales in the United States. We plan to conduct a phase 2 trial to provide experience with different dosing regimens of TransCon PTH, is successful, based in part on the extensive clinical experienceand with titration ofPTH(1-34) calcium andPTH(1-84), active Vitamin D supplementation. In February 2019, we expect to advance TransCon PTH directly into Phase 3 development in the first quarter of 2019, after consultationsfiled an investigational new drug (IND) application with the FDA for initiation of PaTH Forward, a global phase 2 trial designed to evaluate the safety, tolerability and efficacy of TransCon PTH in adult subjects with hypoparathyroidism (HP). The trial will also evaluate a titration regimen for the European Medicines Agency.complete withdrawal of standard of care (i.e., active vitamin D and calcium supplements) using aready-to-use prefilled pen device. Our plan for our phase 3 program for TransCon PTH includes incorporating trial sites in the United States, Europe, Australia, Canada, Japan and possibly other Asian countries.

TransCon CNP

Market Opportunity in Achondroplasia

Achondroplasia is the most common form of dwarfism, affectingoccurring in about 1 in 10,000 to 30,000 newborns or approximately 250,000 patients worldwide. Achondroplasia results in severe skeletal complications and comorbidities, including spinal stenosis due to premature fusion of the foramen magnum, sleep apnea, and chronic ear infections. Patients often face multiple surgeries to alleviate its many complications. There are currently noFDA-approved pharmacological treatments for achondroplasia.

Achondroplasia is caused by an autosomal dominant activating mutation in fibroblast growth factor receptor 3, or FGFR3 that leads to an imbalance in the effects of the FGFR3 andC-type natriuretic peptide (CNP) signaling pathways. In achondroplasia, mutations in FGFR3 result in constitutive activation, suppressing the proliferation and differentiation of chondrocytes resulting in improper cartilage to bone conversion in the growth plate.

Preclinical and clinical data show that the CNP pathway stimulates growth and increased CNP helps to counteract the effects of the FGFR3 mutation downstream. Administration of CNP to patients with achondroplasia and in animal models of achondroplasia has been found to stimulate growth. Clinicalproof-of-principle was recently obtained for vosoritide,

Figure 1. The role of a once-daily formulationdefect in the FGFR3 signaling pathway in the development of CNP. In April 2016, BioMarin Pharmaceuticals announced that its Phase 2 trial has shown that daily injections of the CNP analogue, vosoritide, in children with achondroplasia increased height velocity by approximately 50% after 12 months of treatment. Together, these results indicate that treatment with systemic CNP is a promising therapeutic strategy for achondroplasia.well understood.

Our Solution: TransCon CNP

Endogenous CNP has an extremely short half-life of only approximately two minutes. Vosoritide, a CNP analogue, has been developed to provide better stability of CNP, and has a half-life of about 20 minutes. However, short-acting CNP analogues that result in high Cmax levels may cause adverse cardiovascular effects. As achondroplasia is caused by an FGFR3 mutation that chronically inhibits growth, we expect a more constant CNP exposure to correlate with better therapeutic outcomes.

TransCon CNP is a long-actingC-type natriuretic peptide designed to optimizeprovide sustained CNP efficacy withexposure at therapeutic levels as a well-tolerated and convenient once-weekly dosage by maintaining sustained therapeutic CNP levels that are hemodynamically safe.dose. It is being developed for the treatment of children with achondroplasia. TransCon CNP is designed to provide effective shielding of CNP from neutral endopeptidase degradation in subcutaneous tissue and the blood compartment, minimize binding of CNP to theNPR-C receptor to decrease clearance and reduce binding of CNP to theNPR-B receptor in the cardiovascular system to avoid hypotension. It releases CNP, which is small enough in size to allow effective penetration into growth plates.

Our preclinical development demonstrated that combining TransCon technologytechnologies with CNP creates a prodrug that slowly releases unmodified CNP resulting in a half-life in primates of approximately 72 hours, representing a more than 1,000 fold1,000-fold longer half-life than native CNP. This is a substantial increase compared to both wild-type CNP and vosoritide, which have half-lives of approximately 2 and 20 minutes, respectively. We believe this will enable weekly administration of TransCon CNP, avoiding the high concentrations of CNP that may cause adverse cardiovascular effects, while maintaining efficacious CNP levels. The goal is to provide a safer and more efficacious therapy for achondroplasia than daily administration of short-acting CNP analogues.

PreclinicalAdditional preclinical studies of TransCon CNP support this target product profile and have demonstrated a dose-dependent effect on growth without adverse cardiovascular effects in therapeutic relevant doses. In addition, TransCon CNP has demonstrated the potential to address the more disablingco-morbidities such as spinal stenosis in a mouse model of achondroplasia. We believe TransCon CNP may provide enhanced efficacy with improved safety and convenience for not only achondroplasia, but also other FGFR-related rare diseases.

Development of TransCon CNP

We completed a preclinical juvenile primate study comparing weekly TransCon CNP to an approximately three times higher cumulative daily dose of a synthesized molecule with the same amino acid sequence as vosoritide. Based on data from this study, both TransCon CNP and the synthesized molecule with the same amino acid sequence as vosoritide demonstrated a trend of increased bone growth over vehicle-treated monkeys.

We are expandingClinical Development of TransCon CNP

In November 2018, we reported preliminary results from a phase 1 trial of TransCon CNP in healthy adult subjects, which supported our manufacturing capabilitiestarget product profile for TransCon CNP. In this phase 1, double-blind, randomized, placebo-controlled trial, 45 healthy adult subjects were enrolled. Five doses of TransCon CNP were tested sequentially, beginning with the lowest dose: 3, 10, 25, 75 and 150 micrograms per kilogram. Up to support continued development10 subjects in each dose cohort were randomized to receive TransCon CNP or placebo in a 4:1 ratio. After each cohort completed dosing, a Data Safety Monitoring Board reviewed the blinded data to approve escalation to the next higher dose. The primary endpoint was frequency of adverse events after administration of TransCon CNP. In addition, we initiated regulatory filingsSecondary endpoints included additional safety parameters, tolerability and pharmacokinetics.

The results showed TransCon CNP provided continuous exposure to CNP with a pharmacokinetic profile designed to provide efficacy with once-weekly dosing. No serious adverse events were reported in the trial and TransCon CNP was generally well tolerated at doses up to 150 microgram/kilogram. Mean orthostatic changes in vital signs appeared unrelated to TransCon CNP exposure and were consistent between placebo and TransCon CNP cohorts. Mean resting blood pressure and heart rate were unchanged frompre-dose at all time points, in all cohorts. Injections were well tolerated in all dose cohorts with no reported injection-related adverse events. These results highlight the potential for TransCon CNP to have a significant impact on patients’ lives, not only affecting height but also addressing the many comorbidities associated with achondroplasia.

We expect to initiate a phase 2 trial of TransCon CNP in pediatric subjects with achondroplasia in the fourththird quarter of 20172019. In parallel, we are conducting the ACHieve Study, a natural history study designed to support a Phase 1 trial in healthy subjectsgain insight into the experience of pediatric patients with achondroplasia. ACHieve will study growth velocity, body proportionality, and comorbidities over time of children with achondroplasia up to establish a tolerable dose range. The Phase 1 trial8 years old. No study medication will be administered. In February 2019, we were granted orphan drug designation by the FDA for TransCon CNP. Our goal is to develop TransCon CNP as a safe and effective therapeutic option for achondroplasia and potentially other related growth disorders.

Figure 2. Pharmacokinetic results for TransCon CNP 10, 25, 75 and 150 microgram/kg administered as a once-weekly subcutaneous injection are presented. As shown, a dose-related increase in CNP exposure was seen and the effective half-life of CNP was found to be conducted in Australia in healthy subjects andapproximately 90 hours, which is planned to initiate dosing insignificantly higher than the second quarterhalf-life of 2018, with data expected in the fourth quarter of 2018.native CNP (approximately two minutes).

TransCon for Oncology

Market Opportunity in Oncology

Cancer remains a major unmet medical need and the incidence of many cancer types continues to rise. Improved understanding of the cellular and molecular mechanisms involved in anti-tumor immune responses has fueled the rapid growth of immuno-oncology therapeutics. In particular, immune checkpoint inhibitors, such asanti-PD-1,anti-PD-L1 andanti-CTLA-4 antibodies, have provided new therapeutic options for patients who did not respond to previous therapies. Supported by these and other advancements, oncology is now the largest therapy class in terms of revenue in pharmaceutical industry, with worldwide prescription drug andover-the-counter sales of $94 billion in 2016 with projected growth to $192 billion in 2022.

Despite these recent advances, there is still a high unmet medical need for new treatment options, as many patients do not respond to current therapies and the efficacy is often limited by toxicities that result in dose reductions or treatment discontinuations. One approach to minimizing adverse events while retaining or improving efficacy is to create product candidates with longer half-lives, allowing for more consistent circulating drug levels and less frequent administration than the corresponding wild-type molecules. Another approach is intratumoral injection, which is to directly administer a drug to the tumors. Early clinical results for intratumoral treatment of cutaneous tumors are encouraging, but the frequent administration of short-acting molecules todifficult-to-access tumors is often impractical. Increased and prolonged therapeutic activity in tumors has the potential to improve outcomes in patients with suboptimal responses to current therapies.

Our Solution: TransCon Technologies for Oncology

Our TransCon technologies can be designed for sustained systemic or localized, intratumoral administration to provide durable and potent anti-tumor effects. TransCon product candidates have the potential to facilitate all the critical steps of the cancer immunity cycle that lead to eradication of malignant cells. TransCon product candidates can be designed to optimize the efficacy of clinically validated therapies while limiting adverse effects. For example, many therapies are administered at the maximum tolerated dose, and the ability to deliver therapies directly to the tumor may improve tolerability as well as improving efficacy, as high local drug concentration can be achieved, while maintaining low systemic exposure. In addition, TransCon product candidates are designed for sustained release, so they may allow for less frequent dosing, enabling treatment of tumor types that cannot be injected frequently.

We have conducted nonclinical studies that have found that TransCon oncology product candidates can slowly release immune-oncology agents, highlighting their potential to enhance the immune system to attack malignant tumor cells. In a syngeneic mouse tumor model, the TransCon TLR agonist resulted in potent inhibition of tumor growth following a single intratumoral injection.

Development of TransCon Oncology Products

Our goal is to improve treatment efficacy while limiting or reducing toxicity by applying TransCon technologies to clinically validated drugs, using our unique algorithm for product innovation. We are conducting preclinical studies within the field of oncology to explore multiple potential product candidates and evaluate systemic as well as localized delivery systems using our TransCon technologies. We are evaluating multiple TransCon product candidates in preclinical research studies for the treatment a variety of tumor types. Examples of TransCon product candidates under evaluation include stimulators of innate and adaptive immunity, as well as modulators of the tumor environment. We are exploring systemic and intratumoral administration both as a monotherapy and as a component of combination regimens.

Strategic Collaborations

We also engage in multi-product strategic collaborations to further leverage our TransCon technology platforms in certain geographies with market-leading biopharmaceutical companiescompanies. These collaborations aim to further monetize our TransCon technology platformplatforms beyond our internal, wholly-owned product candidates, particularly into therapeuticstherapeutic areas where we believe a partner may have more expertise, capability and capital. In addition, we may choose to pursue a collaboration to develop and market our internal, wholly-owned product candidates in geographic markets outside our core focus of the United States and Europe.

Outside rare endocrine disorders, we currently have multi-product collaborations with market-leading pharmaceutical companies who are applying our TransCon technologytechnologies to build a pipeline of sustained releasesustained-release prodrug product candidates. These include collaborations with Genentech in the field of ophthalmology and Sanofi in the field of diabetes. We are eligible to receive up to an aggregate of €200 million in development and regulatory milestone payments for products currently being developed under our collaboration agreements, as well as sales-based milestone payments and royalties on future net sales of such products.

Sanofi: TransCon Peptides

Overview and Market Opportunities

Together with our collaboration partner, Sanofi, we are developing TransCon peptides for the treatment of diabetes, a major cause of morbidity and mortality across the world. The current standard of care for diabetes often includes daily injections. Compliance and adherence to such regimens are poor due to the burden of daily injections. According to the WHO, diabetes is a global epidemic with 347 million people worldwide having diabetes. The diabetes market is expected to increase due in part to increasing obesity rates.

Our Solution: TransCon Peptides

With our collaboration partner, Sanofi, we are researching and developing long-acting TransCon prodrugs for the treatment of diabetes. Our TransCon prodrugs are designed to enable safe and efficacious levels of unmodified drug and provide extended dosing profiles. Sanofi is currently evaluating the safety and efficacy of various TransCon prodrug candidates for the treatment of diabetes.

Strategic Collaboration with Sanofi

In December 2010, we entered into a strategic collaboration agreement with Sanofi under which we assigned to Sanofi certain diabetes-related patent rights, and granted to Sanofi an exclusive, worldwide, royalty-free license to research, develop, make and commercialize (1) products based on the TransCon technologytechnologies and any combination ofglucagon-like-peptide-1, orGLP-1, glucagon and insulin to treat any diseases in humans or animals, or (2) any other product developed by Sanofi incorporating our TransCon technology,technologies, other technology covered by the assigned patents or other improvements to our TransCon technologytechnologies or the foregoing products, to treat diabetes in humans or animals. During the term of the agreement, we are prohibited from engaging in any research, development or commercialization activities related to certain specified products. In addition, we granted Sanofi anon-exclusive, royalty-free license to research, develop, manufacture and commercialize products other than those based on the TransCon technologytechnologies and any combination ofGLP-1, glucagon and insulin that are developed by Sanofi incorporating our TransCon technology,technologies, other technology covered by the assigned patents or other improvements to our TransCon technologytechnologies or the foregoing products for the treatment of certain diabetes-related metabolic disorders and obesity in humans and animals, so long as, for any such products that are peptides, Sanofi first develops them for diabetes or obesity in humans and the first application for regulatory approval for such products is for diabetes or obesity in humans in a major country, and for any such products that are not peptides, Sanofi first develops such products for diabetes in humans and animals and the first application for marketing approval is for diabetes in humans in a major country. This license will become exclusive, on apeptide-by-peptide basis, for any licensed product containing a peptide that isnon-proprietary to Sanofi and is designated by Sanofi if certain specified conditions are met. Under the agreement, Sanofi has granted us anon-exclusive, royalty-free license (with the right to grant sublicenses) under Sanofi’s rights in any improvements generated in connection with the collaboration, to research, develop, make or commercialize products outside the scope of the collaboration and outside the field of diabetes.

In consideration for these licenses to the TransCon technologytechnologies and as payment for the assignment of specific diabetes-related product patents, Sanofi provided an aggregate of €25 million innon-refundable,up-front payments to us. Sanofi also committed to fund our development activities for a fixed amount over the first three years of the collaboration, in accordance with an agreed upon development plan. For the first two products developed under the Sanofi collaboration, we are also eligible to receive up to an aggregate of €170 million upon Sanofi’s achievement of specified clinical development and regulatory approval milestones and up to an aggregate of €100 million upon Sanofi’s achievement of certain sales-related milestones.

The term of the agreement expires upon the expiration of the last to expire of the patents licensed or assigned to Sanofi under the agreement and we currently expect thelast-to-expire licensed or assigned patent will expire in October 2030. We may terminate the agreement upon 30 days’ prior written notice if Sanofi fails to remit any undisputed sum it must pay to us. Each party may terminate the agreement upon 60 days’ prior written notice for the other party’s uncured material breach. Sanofi has the right to terminate the agreement in its entirety for convenience upon 90 days’ prior written notice. Either party may terminate the agreement by written notice to the other party if the other party institutes a lawsuit or proceeding allegingnon-infringement, invalidity or unenforceability with respect to any patent licensed to such other party under the agreement. Upon any such termination by us or by Sanofi for convenience, all licenses granted to Sanofi would terminate and, if such termination is by Sanofi for convenience prior to IND approval of a product under the agreement, we may require Sanofi to assign back to us the assigned patent rights upon payment of a specified amount.

Genentech: TransCon anti-VEGF

Overview and Market Opportunity

TransCon anti-VEGF is a novel compound designed to support up to half-yearly injection of anti-VEGF. Anti-VEGF, also known as anti-vascular endothelial growth factor, therapy currently requires periodic intravitreal injections, or injections into the back of the eye. Lucentis^® is the first anti-VEGF indicated for neovascular wetage-related macular degeneration, macular edema following retinal vein occlusion and diabetic macular edema and has been transformative in the treatment of these diseases. Prior to the introduction of Lucentis^®, most patients experienced progressive and inevitable vision loss. Now patients routinely gain back significant vision and maintain those gains for several years. By working together with Genentech and combining the TransCon technologytechnologies with anti-VEGF, we seek to continue to lead innovation in this therapeutic category by significantly reducing the injection frequency and associated patient burden.

There is high interest in developing longer acting therapies for intravitreal drug delivery to reduce the burdensome intravitreal injections required by the current standard of care. In this market, patient compliance remains a challenge and patients and physicians sometimes accept less than optimal dosing frequencies for certain individuals. A reliable and consistent method to achieve visual gains with up to half-yearly dosing represents a potential major breakthrough and could quickly become the new standard of care.

Limitations of Established Long-acting Intravitreal Technologies

Several types of drug-eluting ocular implants are approved in the United States, ranging from biodegradable inserts tonon-biodegradable reservoirs.Non-biodegradable implants must be removed after a period of time requiring an additional invasive procedure. Biodegradable systems do not require removal, but are generally associated with erratic drug release and burst release.

Our Solution: TransCon anti-VEGF

Our approach provides a unique opportunity to reduce the frequency of intravitreal injections while enabling the predictable release of an active parent drug from our biodegradable carrier system. We believe our TransCon technologytechnologies may enable intravitreal delivery of a variety of molecules, including small molecules, peptides and proteins. Our precise, predictable release of the unmodified drug within the vitreous chamber may maintain therapeutic levels of drug with up to half-yearly administration.

TransCon anti-VEGF is a novel prodrug designed to support up to half-yearly administration frequency, and to provide the same or improved efficacy compared to current intravitreal anti-VEGF injections. Genentech is currently evaluating the safety of various TransCon anti-VEGF prodrug candidates for intravitreal administration.

Strategic Collaboration with Genentech

In July 2013, we entered into a strategic collaboration agreement with Genentech and Roche, referred to collectively as Genentech, under which we granted Genentech an exclusive, worldwide royalty-bearing license to make, use and commercialize products based on the TransCon technologytechnologies and any therapeutic or prophylactic compound, other thanGLP-1, glucagon and/or insulin, for the treatment and/or prevention of any disease, condition or disorder of the eye, other than diabetic retinopathy. We also granted to Genentech a worldwide,non-exclusive, royalty-bearing license to make, use and commercialize such products to treat diabetic retinopathy. Under the agreement, we are prohibited from conducting, or granting rights to third parties to conduct in connection with any generic version of licensed products, any research, development or commercialization of the licensed intellectual property and technology rights for use in treatment or prevention of any ophthalmic condition or disorder, or for diabetic retinopathy, subject to certain exceptions and conditions. In addition, during the term of the agreement, we are prohibited from developing or commercializing any licensed product that contains a compound that is either proprietary to Genentech and that is the subject of active research and development efforts or subject to payment obligations under the agreement, or for a specified time period, that is one of a group of compounds commercialized and designated by Genentech, in each case for uses other than the treatment or prevention of any ophthalmic condition or disorder, or diabetic retinopathy. Under the agreement, we own any inventions made by either party solely relating to our TransCon technologytechnologies under the collaboration. Further, we received anon-exclusive, royalty-free license (with the right to grant sublicenses) under Genentech’s rights in any process invention or joint invention generated in connection with the collaboration, to make, use or sell products (other than glucagon product,GLP-1 product and insulin product) outside the field of treatment and/or prevention of any disease, condition or disorder of the eye.

In consideration for these licenses, Genentech paid us anon-refundableup-front technology license fee of $20 million (€(~€15 million), and we are eligible to receive milestone payments upon Genentech’s achievement of specified development milestones and upon the achievement of the first commercial sale in certain specified markets. For each therapeutic or prophylactic compound containing (i) our TransCon technologytechnologies licensed under this agreement and (ii) ranibizumab, the milestone payments shall not exceed $100 million (~€75 million), and for each such compound not containing ranibizumab, the milestone payments under this agreement shall not exceed $80 million (~€60 million). For products commercialized under this agreement, we are also eligible to receive tiered royalties on net sales, subject to customary reductions and offsets. For therapeutic or prophylactic compounds containing ranibizumab, these tiered royalties are at percentages in themid-single digits but not exceeding thelow-teen digits and, for other therapeutic or prophylactic compounds not containing ranibizumab, these tiered royalties are at percentages in themid-single digit range. Genentech also provides funding for our research and development activities under an agreed-upon plan.

The term of the agreement expires on aproduct-by-product andcountry-by-country basis upon expiration of Genentech’s obligation to pay us royalties on the net sales of licensed products, which extends until the later of ten years after the first commercial sale of each licensed product in such country, or the expiration of certain patent rights covering such licensed product in such country. Each party may terminate the agreement upon 60 days’ prior written notice for the other party’s uncured material breach of this Agreement, upon 30 days’ prior written notice for the other party’s uncured material breach that has a serious adverse effect on thenon-breaching party, and upon written notice to the other party upon bankruptcy or insolvency of the other party. Genentech has the right to terminate the agreement in its entirety for convenience upon 90 days’ prior written notice, or on a licensedproduct-by-licensed product basis, by giving 90 days’ written notice prior to the first commercial sale of the applicable licensed product and 180 days’ written notice thereafter. Genentech may also terminate in the event we undergo a change of control in favor of a competitor of Genentech if that competitor does not segregate our personnel and activities under the agreement. We may terminate the agreement upon written notice to Genentech if Genentech challenges in a court the validity, enforceability or scope of licensed patents, other than to defend itself in a legal proceeding involving such patent rights.

CompetitionStrategic Investment

VISEN Pharmaceuticals

In November 2018, we announced the formation of VISEN Pharmaceuticals, or Visen, a company established to develop and commercialize our endocrinology rare disease therapies in the People’s Republic of China, Hong Kong, Macau, and Taiwan, or Greater China. In connection with the formation of Visen, we granted Visen exclusive rights to develop and commercialize certain product candidates based on our proprietary TransCon technologies, including TransCon hGH, TransCon PTH and TransCon CNP, in Greater China for use in all human indications, subject to certain exceptions. As consideration for the rights granted to Visen, we received 50% ownership in the outstanding shares of Visen and concurrently with the rights we granted to Visen, entities affiliated with Vivo Capital and Sofinnova Ventures purchased shares in Visen for an aggregate purchase price of $40 million in cash.

Market Opportunity in China

China is the second largest pharmaceutical market in the world after the United States and represents one of the fastest growing pharmaceutical markets worldwide. In recent years, the Chinese government has initiated a number of regulatory reforms that are expected to accelerate drug development, as well as drive growth and demand for new therapeutics in China. In addition to joining an international organization that standardizes regulations for clinical development, the National Medical Products Administration (NMPA) has introduced initiatives such as fast track review for drugs for unmet medical needs and adopted new rules that streamline the drug approval process in China for global companies.

We believe Visen supports our strategy to extend our endocrinology rare disease portfolio globally and establish a presence in China in partnership with collaborators who have significant experience and knowledge of the biopharmaceutical opportunity in China. In part because Visen was established in China, we believe Visen will be able to effectively develop and, if approved, market our innovative technologies to address the needs of the local markets in Greater China.

Rights Agreements

Under the Rights Agreements, Visen must use diligent efforts to develop and commercialize licensed products in Greater China. Additionally, we and Visen will conduct certain research and development activities allocated to the respective party under a research and technical development plan, and Visen will reimburse us for costs of conducting such activities, including costs of our personnel committed to performing such activities in Greater China.

We will provide product supply to Visen for use in conducting clinical trials in Greater China pursuant to separate clinical supply agreements entered into concurrently with the Rights Agreements in accordance with the terms and conditions set forth therein. Additionally, we and Visen will negotiate in good faith the terms and conditions governing commercial supply of licensed product to Visen on the terms and conditions set forth in the Rights Agreements.

Under the Rights Agreements, we agreed not to research, develop, or commercialize competing products in Greater China, and Visen agreed not to grant certain rights under its interest in any inventions or intellectual property arising out of the activities conducted under the Rights Agreements to third parties, in each case, under the terms and conditions specified in the Rights Agreements. We will have the right to exploit inventions and intellectual property arising out of the activities conducted under the Rights Agreements outside of Greater China. Additionally, we granted Visen a right of first negotiation to develop and commercialize certain of its endocrinology products in Greater China.

The Rights Agreements continue in effect for as long as a valid claim of a licensed patent exists in Greater China. Visen may terminate a Rights Agreement for convenience, for uncured material breach by us of a Rights Agreement and for our bankruptcy or insolvency-related events. We may terminate a Rights Agreement for certain specified material breaches thereof by Visen, in the event Visen undergoes a change of control in favor of a competitor, if Visen challenges the validity of any of the licensed patents and for Visen’s bankruptcy or insolvency-related events.

Shareholders Agreement

In connection with the formation of Visen, on November 7, 2018, we entered into a Shareholders Agreement (the “Shareholders Agreement”) providing for certain rights and obligations of Visen and its shareholders. Pursuant to the Shareholders Agreement, Visen and the Visen shareholders agreed to certain negotiated information and inspection rights, rights relating to registration of shares held by shareholders, pro rata rights to participate in future offerings by Visen of certain securities of Visen subject to certain limited exceptions, drag along provisions relating to a change of control of Visen, rights of first refusal andco-sale with respect to proposed sales (if any) by shareholders of Visen (including sales by us).

Pursuant to the Shareholders Agreement, we have the right to designate an individual for election to the board of directors of Visen and Visen has agreed that certain specified events (including a certain liquidation events) shall require the approval of (i) shareholders of Visen holding at least 60% of Visen’s Series A preferred shares and/or (ii) certain members of the board of directors. Under the Shareholders Agreement and in connection with the formation of Visen, we have agreed to refrain from carrying out, or engaging in, the research, development, manufacture or commercialization of certain competing products in Greater China.

The Shareholders Agreement terminates by written agreement between us and an entity affiliated with Vivo Capital, and automatically terminates upon the dissolution of Visen. In addition, holders of a specified percentage of Series A preferred shares in Visen can terminate the Shareholders Agreement by written notice to Visen upon the occurrence of certain events set forth in the Shareholders Agreement.

Manufacturing

As we do not maintain the capability to manufacture finished drug products, we utilize contract manufacturers to manufacture finished drug product of our proprietary TransCon product candidates intended for clinical or commercial use. We source starting materials for our manufacturing activities from one or more suppliers. For the starting materials necessary for our proprietary TransCon product candidate development, we have agreements for the supply of such starting materials with drug manufacturers or suppliers that we believe have sufficient capacity to meet our demands. However, from time to time, we source critical raw materials and services from one or a limited number of suppliers and there is a risk that if such supply or services were interrupted, it would materially harm our business. In addition, we typically order raw materials and services on a purchase order basis and do not enter into long-term dedicated capacity or minimum supply arrangements. We utilize the services of contract manufacturers to manufacture drug substance required for later phases of clinical development and eventual commercialization for us under all applicable laws and regulations.

We have analytical and process development capabilities in our own facility. We generally perform analytical and process development for our proprietary TransCon product candidates internally and manufacture internally our TransCon product candidates necessary to conduct thenon-GLP preclinical studies thereof. However, we occasionally outsource the manufacture of research and development-stage TransCon product candidates. Occasionally our collaboration partners may manufacture the research and development-stage TransCon product candidates for which they are licensed. Each of our collaboration partners have granted us rights that enable us to freely commercialize all improvements to the TransCon prodrug technologies and manufacturing process developed by our collaboration partners outside of the fields of use and/or territories (as applicable) licensed to such collaboration partners under the relevant collaboration agreements with such partners.

We do not have, and we do not currently plan to acquire or develop, the facilities or capabilities to manufacture bulk drug substance or filled drug product for use in human clinical trials. We rely on third-party manufacturers to produce the bulk drug substances required for our clinical trials and expect to continue to rely on third parties to manufacture and test clinical trial drug supplies for the foreseeable future.

Our contract suppliers manufacture drug substance and finished drug product for our TransCon product candidates for clinical trial use in compliance with cGMP and applicable local regulations. cGMP regulations include requirements relating to organization of personnel; buildings and facilities; equipment; control of components and drug product containers and closures; production and process controls; packaging and labeling controls; holding and distribution; laboratory controls; records and reports; and returned or salvaged products. The manufacturing facilities for our products must be in compliance with cGMP requirements, and for device and device components, the Quality System Regulation, or QSR, requirements, before any product is approved. We ensure cGMP compliance of our suppliers through regular quality inspections performed by our Quality Assurance group. Our third-party manufacturers may also be subject to periodic inspections of facilities by the FDA, the Competent Authorities of the Member States of the European Economic Area (EEA, comprising the 28 Member States of the European Union plus Norway, Iceland and Liechtenstein), and other authorities, including reviews of procedures and operations used in the testing and manufacture of our products to assess our compliance with applicable regulations. Failure to comply with statutory and regulatory requirements subjects a manufacturer to possible legal or regulatory action, including warning letters, the seizure or recall of products, injunctions, consent decrees placing significant restrictions on or suspending manufacturing operations and civil and criminal penalties. These actions could have a material impact on the availability of our products. In addition, contract manufacturers often encounter difficulties involving production yields, quality control and quality assurance, as well as shortages of qualified personnel.

We also contract with additional third parties for the filling, labeling, packaging, testing, storage and distribution of our TransCon product candidates. We employ personnel with the significant scientific, technical, production, quality and project management experience required to oversee our network of third-party suppliers and to manage manufacturing, quality data and information for regulatory compliance purposes.

NOF Manufacturing and Supply Agreement

On December 21, 2017, we entered into a multi-year Manufacturing and Supply Agreement (the “NOF Agreement”) with NOF Corporation (“NOF”). Under the NOF Agreement, NOF has agreed to manufacture and supply the mPEG Linker (the “NOF Product”) for our TransCon GHhGH product candidate. We have agreed to purchase certain quantities of NOF Product. We may purchase NOF Product from other manufacturers and are not obligated to purchase NOF Product from NOF, other than certain quantities that have been forecasted by us in accordance with a mandatory rolling forecast that we must deliver to NOF from time to time.

The NOF Agreement is effective as of December 21, 2017. The initial term of the NOF Agreement terminates on December 31, 2025 unless earlier terminated. The parties may extend the initial term of NOF Agreement pursuant to a written agreement until five years following the finalization of NOF’s capacity expansion. After the expiration of the initial term of the NOF Agreement, the NOF Agreement continues until it is terminated. The NOF Agreement may be terminated (i) by either party for the other party’s assignment of the NOF Agreement for the benefit of creditors, insolvency, bankruptcy, liquidation, dissolution, or the taking of any action by the other party under an act for relief from creditors, (ii) by either party for the other party’s uncured material breach, (iii) by us after the initial term of the NOF Agreement with one year written notice, or (iv) by mutual agreement of the parties. In addition, the NOF Agreement may be terminated by us in the event of a change of fifty percent or more of the direct or indirect ownership of NOF or manufacturing facilities relevant to the NOF Agreement, if such ownership goes to a third party materially involved in the treatment of growth related disorders in humans. The NOF Agreement may also be terminated by either party for a continuing event of force majeure.

The NOF Agreement contains, among other provisions customary representations and warranties by us and NOF, grants certain limited license rights related to either party’s intellectual property in connection with the manufacturing and supply of NOF Product, provides for certain indemnification rights in favor of both parties and customary confidentiality provisions.

Carbogen Manufacturing and Supply Agreement

On October 26, 2018, we entered into a multi-year Manufacturing and Supply Agreement (the “Carbogen Agreement”) with Carbogen Amcis AG (“Carbogen”). Under the Carbogen Agreement, Carbogen has agreed to manufacture and supply the C13 Linker (the “Carbogen Product”) for our TransCon hGH product candidate. We may purchase C13 Linker from other manufacturers and are not obligated to purchase Carbogen Product from Carbogen, other than certain quantities that have been forecasted by us in accordance with a mandatory rolling forecast that we must deliver to Carbogen from time to time.

The Carbogen Agreement is effective as of October 26, 2018. The initial term of the Carbogen Agreement expires five years after the first commercial launch of our TransCon hGH product candidate (the “Carbogen Initial Term”) unless earlier terminated. After the expiration of the Carbogen Initial Term of the Carbogen Agreement, the Carbogen Agreement continues until it is terminated. The Carbogen Agreement may be terminated (i) by either party for the other party’s assignment of the Carbogen Agreement for the benefit of creditors, insolvency, bankruptcy, dissolution, or taking of any action under an act for relief from creditors, (ii) by either party for the other party’s uncured material breach, (iii) by us after the Carbogen Initial Term of the Carbogen Agreement with one year written notice, (iv) by Carbogen after the Carbogen Initial Term of the Carbogen Agreement with four years written notice (subject to Carbogen’s technology transfer obligation to an alternate supplier) or (iv) by mutual agreement of the parties. In addition, the Carbogen Agreement may be terminated by us in the event of a change of fifty percent or more of the direct or indirect ownership of Carbogen, if such ownership goes to a third party materially involved in the treatment of growth-related disorders in humans. The Carbogen Agreement may also be terminated by either party for a continuing event of force majeure.

The Carbogen Agreement contains, among other provisions, certain representations and warranties by us and Carbogen, grants certain rights to intellectual property relating to, or inventions made in connection with, the manufacturing and supply of Carbogen Product, provides for certain indemnification rights in favor of both parties and includes confidentiality provisions.

Philips Medisize (formerly B&O Medicom and Medicom Innovation Partner)

On January 12, 2017, we entered into a multi-year Manufacturing and Supply Agreement (the “Medicom Agreement”) with Medicom Innovation Partner (“Medicom”). Under the Medicom Agreement, Medicom has agreed to exclusively manufacture and supply the auto injector injection device (the “Medicom Product”) for our TransCon hGH product candidate. We are obligated to purchase certain quantities that have been forecasted by us in accordance with a mandatory rolling forecast that we must deliver to Medicom from time to time.

The Medicom Agreement is effective as of January 12, 2017. The term of the Medicom Agreement terminates on June 30, 2025 (“Initial Term”) unless earlier terminated or unless extended unilaterally by us, with notice of extension to be given no later than June 30, 2024, by five years until June 30, 2030 (“Extended Term”) after which date it shall continue indefinitely unless terminated. The Medicom Agreement may be terminated (i) by either party for the other party’s bankruptcy or insolvency-related events, (ii) by either party for the other party’s uncured material breach, (iii) by us by not extending the Initial Term into the Extended Term, (iv) by Medicom after the Extended Term of the Medicom Agreement with two year’s advance written notice or by us after the Extended Term of the Medicom Agreement with one year’s advance notice, or (v) by Medicom if we purchase less than an agreed volume of the Medicom Product (provided that we may avoid such termination by paying Medicom’s lost profits up to such agreed minimum volume). In addition, the Medicom Agreement may be terminated by us in the event of a change of control of Medicom, if such control goes to a third party materially involved in the treatment of certain defined endocrinology disorders in humans. In all events of termination Medicom is obligated to support a tech transfer of manufacture of Medicom Product to an alternate supplier.

The Medicom Agreement contains, among other provisions certain representations and warranties by us and Medicom, grants certain limited license rights related to either party’s intellectual property in connection with the manufacturing and supply of Medicom Product, provides for certain indemnification rights in favor of both parties and includes confidentiality provisions.

Vetter Pharma International GmbH

On December 14, 2018, we entered into a multi-year Supply Agreement (the “Vetter Agreement”) with Vetter Pharma International (“Vetter”). Under the Vetter Agreement, Vetter has agreed to manufacture andfill-and-finish drug product in dual-chamber cartridges (the “Ascendis Product”) for our TransCon hGH product candidate. Vetter has agreed to supply in accordance with a long-term forecast in addition to a rolling forecast with a binding part that we must deliver to Vetter from time to time.

The Vetter Agreement is effective as of January 1, 2019. The term of the Vetter Agreement expires on the five-year anniversary of the date of first regulatory approval of the TransCon hGH product (the “Initial Term”) after which term it shall be automatically renewed for subsequenttwo-year terms unless terminated. The Vetter Agreement may be terminated (i) by either party for the other party’s uncured material breach, including certain enumerated events constituting material breach such as bankruptcy or insolvency-related events, (ii) by us with two years’ notice, with effect no earlier than two years after expiry of the Initial Term or (iii) by either party if the other party is taken over by our or a Vetter competitor, as applicable.

The Vetter Agreement contains, among other provisions, certain representations and warranties by us and Vetter, grants certain limited license rights in connection with Vetter’s manufacturing and supply, and our sale, distribution and other use, of Ascendis Product, provides for certain indemnification rights in favor of both parties and includes confidentiality provisions.

Fujifilm Commercial Supply Agreement

On January 9, 2019, we entered into a multi-year Commercial Supply Agreement (the “Fujifilm Agreement”) with Fujifilm Diosynth Biotechnologies UK Ltd. (“Fujifilm”). Under the Fujifilm Agreement, Fujifilm has agreed to manufacture and supply TransCon hGH Drug Substance (the “Fujifilm Product”) for our TransCon hGH product candidate. We may purchase TransCon hGH Drug Substance from other manufacturers and are not obligated to purchase Fujifilm Product from Fujifilm, other than a total of 6 batches each year in 2020 and 2021.

The Fujifilm Agreement is effective as of January 9, 2019. The initial term of the Fujifilm Agreement expires on December 31 in the year of the five year anniversary of the first commercial sale of our TransCon hGH product candidate (the “Fujifilm Initial Term”) unless earlier terminated. After the expiration of the Fujifilm Initial Term of the Fujifilm Agreement, the Fujifilm Agreement continues until it is terminated. The Fujifilm Agreement may be terminated (i) by either party for the other party’s bankruptcy or insolvency-related events, (ii) by either party for the other party’s uncured material breach or material breach that is not capable of remedy, (iii) by us after the Fujifilm Initial Term of the Fujifilm Agreement with two years written notice, or (iv) by Fujifilm after the Fujifilm Initial Term of the Fujifilm Agreement with five years written notice. We are entitled to terminate the Fujifilm Agreement

with regards to the manufacture of recombinant hGH after one year following launch with two years written notice. In addition, the Fujifilm Agreement may be terminated by us in the event of a change in control of Fujifilm, where the new controlling entity is our competitor. The Fujifilm Agreement may also be terminated by either party for a continuing event of force majeure.

The Fujifilm Agreement contains, among other provisions, certain warranties by us and Fujifilm, grants certain limited license rights related to either party’s intellectual property in connection with the manufacturing and supply of Fujifilm Product, provides for certain indemnification rights in favor of both parties and includes confidentiality provisions.

Competition

The pharmaceutical industry is very competitive and subject to rapid and significant innovation. Our potential competitors include major multinational pharmaceutical companies, established biotechnology companies, specialty pharmaceutical and generic drug companies, universities, and other research institutions. Many of our competitors have greater resources, as well as larger research and development stafffunctions and more experienced marketing and manufacturing organizations. As a result, these companies may obtain regulatory approval more rapidly than we are able to and may be more effective in selling and marketing their products.

Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large, established companies. Our competitors may succeed in developing, acquiring or licensing technologies and drug products that are superior to, or more effectively marketed than, the product candidates that we are currently developing or that we may develop, which could render our products obsolete and noncompetitive. For additional information regarding the companies that may be competitive with our product candidates currently in development, please see the descriptions of our current product candidates included above under the caption “TransCon Product Candidates.”

In addition, many of our competitors have greater experience than we do in conducting preclinical and clinical trials and obtaining FDA and other regulatory approvals. Accordingly, our competitors may succeed in obtaining FDA or other regulatory approvals for drug candidates more rapidly than we do. Companies that complete clinical trials, obtain required regulatory authority approvals and commence commercial sale of their drugs before their competitors may achieve a significant competitive advantage. Drugs resulting from our research and development efforts or from our joint efforts with collaboration partners therefore may not be commercially competitive with our competitors’ existing products or products under development.

We are aware that other companies are developing or evaluating enhanced drug delivery and sustained release technologies, which may be competitive with our TransCon technology.technologies. In particular, we believe Nektar Therapeutics, OPKO Health, Inc., ProLynx LLC and Serina Therapeutics, Inc. are developing technology platforms in the areas of enhanced drug delivery and reversible linkers that may be competitive with our TransCon technology.technologies. We also expect that technological developments will occur at a rapid rate and that competition is likely to intensify as various enhanced delivery and sustained released technologies may achieve similar advantages.

For more information about our revenue and where we compete, please see Note 4 to our audited consolidated financial statements included in Item 18 of this annual report.

Intellectual Property

We actively seek to protect the intellectual property and proprietary technology that we believe is important to our business, which includes seeking and maintaining patents covering our technology,i.e., TransCon linkers and carriers, specific lead candidate structures, broad product concepts, proprietary processes and any other inventions that are commercially and/or strategically important to the development of our business. We also rely on trade secrets that may be important to the development of our business and actively seek to protect the confidentiality of such trade secrets.

Our success will depend on our ability to obtain and maintain patent and other proprietary protection for commercially important technology, inventions andknow-how related to our business, defend and enforce our patents, preserve the confidentiality of our trade secrets and operate without infringing the valid and enforceable patents and proprietary rights of third parties. For more information, please see “Risk Factors—Risks Related to Our Intellectual Property and Information Technology.”

As of December 31, 2017,2018, we own a total of 5764 patent families, of which 2217 are currently in their priority year or international phase and we own several granted patents in the United States (17)(24), Europe (5)(8), Australia (20)(22), Canada (7)(9), China (7), Israel (6)(9), Korea (2), Malaysia (2), New Zealand (3)(4), Japan (10)(15), Mexico (9), Singapore (3)(5), Russia (3)(5) and South Africa (9)(12) and have approximately 203283 pending national/regional applications in a total of 19 jurisdictions (excluding the member states of the European Patent Convention in which our European patents were validated).

So far none of our granted patents has been subject to opposition proceedings, appeals or similar actions aiming at revoking or restricting the scope of a granted patent.

The patent portfolios for the fields containing our most advanced product candidates as of December 31, 20172018 are summarized below and the expected expiration dates included in the summary below do not give effect to patent term extensions that may be available.

TransCon GHhGH

Our patent portfolio related to TransCon GHhGH includes six patent families relating to different aspects of TransCon GHhGH and an additional nine patent families covering various aspects of the auto-injector device for administration of TransCon GH.hGH. The first of these patent families is a composition of matter patent family directed to the particular stoichiometry of TransCon GHhGH and a related TransCon carrier. As of December 31, 2017,2018, this patent family included patents granted in Europe and the United States and a patent application in Europe. We expect any patents granted in this patent family to expire in October 2024.

The second of these patent families is a composition of matter patent family directed to a TransCon linker used in TransCon GH.hGH. As of December 31, 2017,2018, this patent family included patents granted in the United States, Australia, Canada, Japan and Mexico and included patent applications in Europe, the United States, and Brazil. We expect any patents granted in this patent family to expire in March 2025.

The third of these patent families is a composition of matter patent family directed to a broad class of TransCon GHhGH lead candidate structures. As of December 31, 2017,2018, this patent family included patents granted in the United States, Europe, Australia, Canada, China, Israel, India, Japan, Mexico, Russia and South Africa and included patent applications in Europe, the United States, Brazil, Canada, India, Japan, Mexico and Russia. We expect any patents granted in this patent family to expire in April 2029.

The fourth of these patent families is a composition of matter patent family directed to specific dry pharmaceutical compositions comprising TransCon GH.hGH. As of December 31, 2017,2018, this patent family included patents granted in the United States, Europe, Australia, Israel, Mexico, Singapore and South Africa and included patent applications in Europe, the United States, Brazil, Canada, China and India. We expect any patents granted in this patent family to expire in December 2030.

The fifth of these patent families is a composition of matter patent family directed to a broad class of TransCon GHhGH lead candidate structures. As of December 31, 2017,2018, this patent family included a patent granted in South Africa and patent applications in the United States, Europe, Australia, Brazil, Canada, Israel, Japan, South Korea, Mexico, New Zealand, Russia Singapore and South Africa.Singapore. We expect any patents granted in this patent family to expire in November 2035.

The sixth of these patent families is directed to a particular dosage regimentregimen for long-acting growth hormone formulations. As of December 31, 2017,2018, this patent family included patent applications in the United States and in Europe. We expect any patents granted in this patent family to expire in November 2035.

Two of the nine patent families covering the auto-injector device consist of an international patent application as of December 31, 2018. As of December 31, 2018, each of the other seven patent families included patent applications in the United States, Europe, Australia, Canada, Japan and New Zealand.

TransCon PTH

Our patent portfolio related to TransCon PTH includes fivesix patent families relating to different aspects of TransCon PTH. The first of these patent families is a composition of matter patent family directed to the TransCon linker used in TransCon PTH. As of December 31, 2017,2018, this patent family included granted patents in the United States, Australia, Canada, China, Israel, Japan, Mexico and South Africa and included patent applications in Europe, the United States, the United Arab Emirates, Brazil Mexico and Russia. We expect any patents granted in this family to expire in January 2029.

The second of these patent families is a composition of matter patent family directed to a broad class of TransCon PTH candidate structures. As of December 31, 2017,2018, this patent family consists of an internationalincluded patent application.applications in the United States, Europe, Australia, Brazil, Canada, China, Indonesia, Israel, India, Japan, South Korea, Mexico, Malaysia, New Zealand, Russia, Singapore, Thailand and South Africa. We expect any patents granted in this patent family to expire in February 2037.

The third and fourth of these patent families are method of treatment patent families directed to a particular dosage regimen. As of December 31, 2017,2018, these patent families consist of an international patent application. We expect any patents granted in this patent family to expire in September 2037.

The fifth of these patent families is a composition of matter family directed to PTH compounds exhibiting a beneficial pharmacokinetic profile. As of December 31, 2017,2018, this patent family consists of an international patent application. We expect any patents granted in this patent family to expire in September 2037.

The sixth patent family relates to a starting dose for treatment with reversible PTH conjugates. As of December 31, 2018, this patent family consists of an EP priority application. We expect any patents granted from this patent family to expire in May 2039.

TransCon CNP

Our patent portfolio related to TransCon CNP includes ten patent families relating to different aspects of TransCon CNP. The first of these patent families is a composition of matter patent family directed to the particular stoichiometry of TransCon CNP and a related TransCon carrier. As of December 31, 2017,2018, this patent family included patents granted in Europe and the United States and a patent application in Europe. We expect any patents granted in this patent family to expire in October 2024.

The second of these patent families is a composition of matter patent family directed to the TransCon linker used in TransCon CNP. As of December 31, 2017,2018, this patent family included granted patents in the United States, Australia, Canada, China, Israel, Japan, Mexico and South Africa and included patent applications in Europe, the United States, the United Arab Emirates, Brazil, Mexico and Russia. We expect any patents granted in this family to expire in January 2029.

The third of these patent families is a composition of matter patent family directed to a broad class of TransCon CNP candidate structures. As of December 31, 2017,2018, this patent family included patent applications in the United States, Europe, Australia, Brazil, Canada, China, Israel, India, Japan, South Korea, Mexico, Malaysia, New Zealand, Russia, Singapore, Thailand and South Africa. We expect any patents granted in this patent family to expire in January 2036.

The fourth to the ninth patent family are composition of matter patent families directed various CNP compounds having beneficial properties. As of December 31, 2017,2018, the first one of these six patent families consistincluded patent applications in the United States, Europe, Australia, Canada, Japan, Mexico, New Zealand and South Africa. As of internationalDecember 31, 2018, the second one included patent applications.applications in the United States, Europe, Australia, Canada, Japan, New Zealand and South Africa. As of December 31, 2018, the third one included patent applications in the United States, Europe, Australia, Brazil, Canada, China, Indonesia, Israel, India, Japan, South Korea, Mexico, Malaysia, New Zealand, Singapore and South Africa. As of December 31, 2018, the fourth one included patent applications in the United States, Europe, Australia, Canada, Israel and New Zealand. As of December 31, 2018, the

fifth one included patent application in the United States, Europe, Australia, Brazil, Canada, China, Israel, South Korea, New Zealand and Singapore. As of December 31, 2018, the sixth one included patent applications in the United States, Europe, Australia, Canada, Israel and New Zealand. We expect any patents granted in this patent family to expire in January 2037.

The tenth patent family covers a combination therapy of TransCon CNP. As of December 31, 2017,2018, this patent family consists of an international patent application. We expect any patents granted from this patent family to expire in September 2037.

Field of Diabetes

In the field of diabetes, our patent portfolio related to TransCon product candidates under development with our collaboration partner, Sanofi, includes four product-specific patent families previously sold to Sanofi and four technology-patent families owned by us andout-licensed to Sanofi. The first patent family owned by us is referred to as our AP006 patent family and this patent family is a composition of matter patent family broadly directed to one of our TransCon linkers. This patent family relates to our TransCon technologies and product candidates in the diabetes and ocular fields, among others. As of December 31, 2017,2018, this patent family included patents granted in the United States, Australia, Canada, China, Israel, Japan, Mexico and South Africa and included patent applications in Europe, the United States, the United Arab Emirates, Brazil, Mexico and Russia. We expect any patents granted in this patent family to expire in January 2029.

The second patent family owned by us is referred to as our AP003 patent family and this patent family is a combination of a composition of matter and a process patent family directed to particular TransCon hydrogels. This patent family relates to our TransCon technologies and product candidates in the diabetes field. As of December 31, 2017,2018, this patent family included twothree patents granted in the United States and included patent applications in Europe and the United States.Europe. We expect any patents granted in this patent family to expire in October 2024.

The third patent family is a composition of matter patent family also directed to aPEG-based hydrogel comprising certain backbone and crosslinker structures. As of December 31, 2017,2018, this patent family included patents granted in Australia, Canada, China, Israel, Japan, South Korea, Mexico, Malaysia, New Zealand, Russia, Singapore and South Africa, and included patent applications in Europe, the United States, Brazil, Indonesia, India and Thailand. We expect any patents granted in this patent family to expire in July 2030.

The fourth patent family owned by us is referred to as our AP019 patent family and this patent family is a process patent family directed to the sterilization of TransCon hydrogels. As of December 31, 2017,2018, this patent family included patents granted in the United States, Europe, Australia, Canada, China, Indonesia, Israel, India, Japan, South Korea, Mexico, Malaysia, New Zealand, Russia, Singapore and South Africa, and included patent applications in Europe, Brazil Canada, Indonesia, India and Thailand. We expect any patents granted in this patent family to expire in October 2030.

Field of Ophthalmology

Our patent portfolio related to our work in the ophthalmology field includes three patent families, one of which is our AP006 patent family which is described above and two product-related patent families, one of which is exclusivelyout-licensed to our collaboration partner, Genentech. Other than the AP006 patent family described above, our patent families related to our work in the ocular fields are described in this section below.

The first patent family is a composition of matter patent family directed to the general concept of using hydrogel prodrugs for the treatment of ocular diseases. As of December 31, 2017,2018, this patent family included granted patents in Australia, New Zealand and South Africa and included patent applications in Europe, the United States, Brazil, Canada, Israel, South Korea, Mexico Malaysia and Singapore.Malaysia. We expect any patents granted in this patent family to expire in October 2032.

The second patent family, which is exclusivelyout-licensed to Genentech, is a composition of matter patent family directed to a broad class of TransCon prodrugs of vascular endothelial growth factor neutralizing drugs. As of December 31, 2017,2018, this patent family included one granted patentpatents in Australia, New Zealand, Russia, Singapore and South Africa and included patent applications in Europe, the United States, Australia, Brazil, Canada, Israel, Japan, South Korea, Mexico Malaysia, New Zealand, Russia and Singapore.Malaysia. We expect any patents granted in this patent family to expire in October 2033.

TransCon TechnologyTechnologies

Our patent portfolio also includes patents and patent applications generally relating to our TransCon technology,technologies, including TransCon linkers, TransCon carriers and certain soluble conjugates. We own an aggregate of ten patent families relating to TransCon linkers, the material components of which are described above. We own an aggregate of sevennine patent families relating to TransCon carriers, the material components of which are described above. Finally, we own a composition of matter patent family that is directed to soluble conjugates in which one drug molecule is connected to one TransCon carrier molecule. As of December 31, 2017,2018, this patent family included patents in Europe and the United States and patent applications in Europe. We expect any patents granted in this patent family to expire in October 2024.

Laws and Regulations Regarding Patent Terms

The term of individual patents depends upon the legal term of the patents in the countries in which they are obtained. In most countries in which we file, the patent term is 20 years from the earliest date of filing anon-provisional patent application. In the United States, a patent term may be shortened if a patent is terminally disclaimed over another patent or if there are delays in patent prosecution by the patentee. A patent’s term may be lengthened by a patent term adjustment, which compensates a patentee for administrative delays by the USPTO in granting a patent. The patent term of a European patent is 20 years from its filing date, which, unlike in the United States, is not subject to patent term adjustments.

The term of a patent that covers anFDA-approved drug or biologic may also be eligible for patent term extension, which permits patent term restoration as compensation for the patent term lost during the FDA regulatory review process. The Drug Price Competition and Patent Term Restoration Act of 1984, or the Hatch-Waxman Act, permits a patent term extension of up to five years beyond the expiration of the patent. The length of the patent term extension is related to the length of time the drug or biologic is under regulatory review. Patent extension cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval and only one patent applicable to an approved drug may be extended. Similar provisions are available in Europe and other jurisdictions to extend the term of a patent that covers an approved drug. In the future, if and when our products receive FDA approval, we expect to apply for patent term extensions on patents covering those products. We anticipate that some of our issued patents may be eligible for patent term extensions.

Manufacturing

As we do not maintain the capability to manufacture finished drug products, we utilize contract manufacturers to manufacture our proprietary drug candidates. We source starting materials for our manufacturing activities from one or more suppliers. For the starting materials necessary for our proprietary drug candidate development, we have agreements for the supply of such drug components with drug manufacturers or suppliers that we believe have sufficient capacity to meet our demands. However, from time to time, we source critical raw materials and services from one or a limited number of suppliers and there is a risk that if such supply or services were interrupted, it would materially harm our business. In addition, we typically order raw materials and services on a purchase order basis and do not enter into long-term dedicated capacity or minimum supply arrangements. We utilize the services of contract manufacturers to manufacture APIs required for later phases of clinical development and eventual commercialization for us under all applicable laws and regulations.

We have analytical and process development capabilities in our own facility. We generally perform drug candidate development, analytical and process development for our proprietary drug candidates internally, and manufacture the drugs necessary to conduct thenon-GLP preclinical studies of our investigational product candidates. We occasionally outsource the production of research and development material. Occasionally our collaboration partners may conduct production of research and development material for products in their respective field. Each of our collaboration partners have granted us rights that enable us to freely commercialize all improvements to the TransCon prodrug technology and manufacturing process developed by our collaboration partners outside of the field identified in their respective collaboration agreements.

We do not have, and we do not currently plan to, acquire or develop the facilities or capabilities to manufacture bulk drug substance or filled drug product for use in human clinical trials. We rely on third-party manufacturers to produce the bulk drug substances required for our clinical trials and expect to continue to rely on third parties to manufacture and test clinical trial drug supplies for the foreseeable future.

Our contract suppliers manufacture drug substance and product for clinical trial use in compliance with cGMP and applicable local regulations. cGMP regulations include requirements relating to organization of personnel; buildings and facilities; equipment; control of components and drug product containers and closures; production and process controls; packaging and labeling controls; holding and distribution; laboratory controls; records and reports; and returned or salvaged products. The manufacturing facilities for our products must be in compliance with cGMP requirements, and for device and device components, the Quality System Regulation, or QSR, requirements, before any product is approved. We ensure cGMP compliance of our suppliers through regular quality inspections performed by our Quality Assurance group. Our third-party manufacturers may also be subject to periodic inspections of facilities by the FDA, the Competent Authorities of the Member States of the European Economic Area (EEA, comprising the 28 Member States of the European Union plus Norway, Iceland and Liechtenstein), and other authorities, including reviews of procedures and operations used in the testing and manufacture of our products to assess our compliance with applicable regulations. Failure to comply with statutory and regulatory requirements subjects a manufacturer to possible legal or regulatory action, including warning letters, the seizure or recall of products, injunctions, consent decrees placing significant restrictions on or suspending manufacturing operations and civil and criminal penalties. These actions could have a material impact on the availability of our products. In addition, contract manufacturers often encounter difficulties involving production yields, quality control and quality assurance, as well as shortages of qualified personnel.

We also contract with additional third parties for the filling, labeling, packaging, testing, storage and distribution of our investigational drug products. We employ personnel with the significant scientific, technical, production, quality and project management experience required to oversee our network of third-party suppliers and to manage manufacturing, quality data and information for regulatory compliance purposes.

Government Regulation and Product Approval

Government authorities in the United States, at the federal, state and local level, and in other countries extensively regulate, among other things, the research, development, testing, manufacture, including any manufacturing changes, safety surveillance, efficacy, quality control, packaging, storage, recordkeeping, labeling, advertising, promotion, distribution, marketing, sale, import, export and the reporting of safety and other post-market information of pharmaceutical and medical device products such as those we are developing. Our product candidatesA new drug must be approved by the FDA through the NDA process and a new biologic must be licensed by the FDA through the BLA process before theyit may be legally promotedmarketed in the United StatesStates. Similarly, new drugs and biologics must be approved by the EMA through the marketing authorization application, or MAA, process before they may be legally marketed in Europe. Our product candidates will be subject to similar requirements in other countries prior to marketing in those countries. The processes for obtaining regulatory approvals in the United States, the EEA and in foreign countries, along with subsequent compliance with appropriate federal, state, local and foreign statutes and regulations, require the expenditure of substantial time and resources.

U.S. Government Regulation

In the United States, we are subject to extensive regulation by the FDA, which regulates drugs under the Federal Food, Drug, and Cosmetic Act, or the FDCA, and itsin the case of biologics, also under the Public Health Service Act, or PHSA, and their implementing regulations, and other federal, state, and local regulatory authorities. The FDCA, PHSA and itstheir implementing regulations set forth, among other things, requirements for the research, testing, development, manufacture, quality control, safety, effectiveness, approval, labeling, storage, record keeping, reporting, distribution, import, export, advertising and promotion of our products. The process of obtaining regulatory approvals and the subsequent compliance with appropriate federal, state, local and foreign statutes and regulations requires the expenditure of substantial time and financial resources. Failure to comply with the applicable U.S. requirements at any time during the product development process, approval process or after approval, may subject an applicant to a variety of administrative or judicial sanctions, such as the FDA’s refusal to approve pending NDAs or BLAs, withdrawal of an approval, imposition of a clinical hold, issuance of warning letters, product recalls, product seizures, total or partial suspension of production or distribution, injunctions, fines, refusals of government contracts, restitution, disgorgement or civil or criminal penalties.

The process required by the FDA before a drug or biologic may be marketed in the United States generally involves the following:

things, to the FDA as part of an IND. Some preclinical testing may continue even after the IND is submitted. An IND automatically becomes effective and a clinical trial proposed in the IND may begin 30 days after the FDA receives the IND, unless during this30-day waiting period, the FDA raises concerns or questions related to one or more proposed clinical trials and places the clinical trial on a clinical hold. In such a case, the IND sponsor and the FDA must resolve any outstanding concerns before the clinical trial can begin. As a result, submission of an IND may not result in the FDA allowing clinical trials to commence. The FDA may also impose clinical holds on a product candidate at any time before or during clinical trials due to safety concerns ornon-compliance. If the FDA imposes a clinical hold, trials may not recommence without FDA authorization and then only under terms authorized by the FDA.

Clinical Trials

Clinical trials involve the administration of the investigational new drugpharmaceutical product to human subjects under the supervision of qualified investigators in accordance with GCP requirements, which include the requirement that all research subjects provide their informed consent in writing for their participation in any clinical trial. Clinical trials are conducted under protocols detailing, among other things, the objectives of the trial, the parameters to be used in monitoring safety, and the effectiveness criteria to be evaluated. A protocol for each clinical trial and any subsequent protocol amendments must be submitted to the FDA as part of the IND. An IRB at each institution participating in the clinical trial must review and approve the plan for any clinical trial before it commences at that institution. Information about certain clinical trials must be submitted within specific timeframes to the National Institutes of Health, or NIH, for public dissemination on their www.clinicaltrials.gov website.

Human clinical trials are typically conducted in three or four sequential phases, which may overlap or be combined:

Progress reports detailing the results of the clinical trials must be submitted at least annually to the FDA and more frequently if serious adverse events occur. Phase 1, Phasephase 2 and Phasephase 3 clinical trials may not be completed successfully within any specified period, or at all. Furthermore, the FDA or the sponsor may suspend or terminate a clinical trial at any time on various grounds, including a finding that the research subjects are being exposed to an unacceptable health risk. Similarly, an IRB can suspend or terminate approval of a clinical trial at its institution if the clinical trial is not being conducted in accordance with the IRB’s requirements or if the drugproduct candidate has been associated with unexpected serious harm to patients. In addition, some clinical trials are overseen by an independent group of qualified experts organized by the sponsor, known as a data safety monitoring board or committee. Depending on its charter, this group may determine whether a trial may move forward at designated check points based on access to certain data from the trial.

During the development of a new drug or biologic, sponsors are given opportunities to meet with the FDA at certain points. These points may be prior to submission of an IND, at the end of Phase 2, and before an NDA or BLA is submitted. Meetings at other times may be requested. These meetings can provide an opportunity for the sponsor to share information about the data gathered to date, for the FDA to provide advice, and for the sponsor and the FDA to reach agreement on the next phase of development. Sponsors typically use the meetings at the end of the Phase 2 trial to discuss Phase 2 clinical results and present plans for the pivotal Phase 3 clinical trial that they believe will support approval of the new drug or biologic. Concurrent with clinical trials, companies usually complete additional animal studies and must also develop additional information about the chemistry and physical characteristics of the product and finalize a process for manufacturing the product in commercial quantities in accordance with cGMP requirements. The manufacturing process must be capable of consistently producing quality batches of the product candidate and, among other things, the manufacturer must develop methods for testing the identity, strength, quality and purity of the final product. Additionally, appropriate packaging must be selected and tested, and stability studies must be conducted to demonstrate that the product candidate does not undergo unacceptable deterioration over its shelf life. While the IND is active and before approval, progress reports summarizing the results of the clinical trials and nonclinical studies performed since the last progress report must be submitted at least annually to the FDA, and written IND safety reports must be submitted to the FDA and investigators for serious and unexpected suspected adverse events, findings from other studies suggesting a significant risk to humans exposed to the same or similar pharmaceutical products, findings from animal or in vitro testing suggesting a significant risk to humans, and any clinically important increased incidence of a serious suspected adverse reaction compared to that listed in the protocol or investigator brochure.

Marketing Approval

Assuming successful completion of the required clinical testing, the results of the preclinical and clinical studies, together with detailed information relating to the product’s chemistry, manufacture, controls and proposed labeling, among other things, are submitted to the FDA as part of an NDA or BLA requesting approval or licensure to market the product for one or more indications. In most cases, the submission of an NDA or BLA is subject to a substantial application user fee. Under the Prescription Drug User Fee Act guidelines that are currently in effect, the FDA has a goal of 10 months from the date of “filing” of a standard NDA for a new molecular entity or original BLA to review and act on the submission. This review typically takes 12 months from the date the NDA or BLA is submitted to the FDA because the FDA has sixty days from receipt to make a “filing” decision,decide whether an application is accepted for filing, as described below.

In addition, under the Pediatric Research Equity Act of 2003 as amended and reauthorized, certain NDAs or BLAs or supplements to an NDA or BLA must contain data that are adequate to assess the safety and effectiveness of the drug or biologic for the claimed indications in all relevant pediatric subpopulations, and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective. The FDA may, on its own initiative or at the request of the applicant, grant deferrals for submission of some or all pediatric data until after approval of the product for use in adults, or full or partial waivers from the pediatric data requirements.

The FDA also may require submission of a risk evaluation and mitigation strategy, or REMS, plan to ensure that the benefits of the drug outweigh its risks. The REMS plan could include medication guides, physician communication plans, assessment plans, and/or elements to assure safe use, such as restricted distribution methods, patient registries, or other risk minimization tools.

The FDA conducts a preliminary review of all NDAs and BLAs within the first 60 days after submission, before accepting them for filing, to determine whether they are sufficiently complete to permit substantive review. The FDA may request additional information rather than accept an NDA or BLA for filing. In this event, the application must be resubmitted with the additional information. The resubmitted application is also subject to review before the FDA accepts it for filing. Once the submission is accepted for filing, the FDA begins anin-depth substantive review. The FDA reviews an NDA to determine, among other things, whether the drug is safe and effective and whether the facility in which it is manufactured, processed, packaged or held meets standards designed to assure the product’s continued safety, quality and purity. The FDA reviews a BLA to determine, among other things whether the product is safe, pure and potent and the facility in which it is manufactured, processed, packed or held meets standards

designed to assure the product’s continued safety, purity and potency.

The FDA may refer an application for a novel drug or biologic to an advisory committee. An advisory committee is a panel of independent experts, including clinicians and other scientific experts, that reviews, evaluates and provides a recommendation as to whether the application should be approved and under what conditions. The FDA is not bound by the recommendations of an advisory committee, but it considers such recommendations carefully when making decisions.

Before approving an NDA or BLA, the FDA typically will inspect the facility or facilities where the product is manufactured. The FDA will not approve an application unless it determines that the manufacturing processes and facilities are in compliance with cGMP requirements and adequate to assure consistent production of the product within required specifications. Additionally, before approving an NDA or BLA, the FDA may inspect one or more clinical trial sites to assure compliance with GCP requirements.

The FDA generally accepts data from foreign clinical trials in support of an NDA or BLA if the trials were conducted under an IND. If a foreign clinical trial is not conducted under an IND, the FDA nevertheless may accept the data in support of an NDA or BLA if the study was conducted in accordance with GCP requirements and the FDA is able to validate the data through anon-site inspection, if deemed necessary. Although the FDA generally requests that marketing applications be supported by some data from domestic clinical studies, the FDA may accept foreign data as the sole basis for marketing approval if (1) the foreign data are applicable to the U.S. population and U.S. medical practice, (2) the studies were performed by clinical investigators with recognized competence, and (3) the data may be considered valid without the need for anon-site inspection or, if the FDA considers the inspection to be necessary, the FDA is able to validate the data through anon-site inspection or other appropriate means.

The testing and approval process for an NDA or BLA requires substantial time, effort and financial resources, and each may take several years to complete. Data obtained from preclinical and clinical testing are not always conclusive and may be susceptible to varying interpretations, which could delay, limit or prevent regulatory approval. The FDA may not grant approval on a timely basis, or at all.

After evaluating the NDA or BLA and all related information, including the advisory committee recommendation, if any, and inspection reports regarding the manufacturing facilities and clinical trial sites, the FDA may issue an approval letter, or, in some cases, a complete response letter. A complete response letter generally contains a statement of specific conditionsComplete Response Letter indicates that must be met to secure final approvalthe review cycle of the application is complete and the application will not be approved in its present form. A Complete Response Letter usually describes the specific deficiencies in the NDA or BLA identified by the FDA and may require additional clinical data, such as an additional pivotal Phase 3 trial or preclinical testingother significant and time-consuming requirements related to clinical trials, nonclinical studies or manufacturing. If a Complete Response Letter is issued, the sponsor must resubmit the NDA or BLA, addressing all of the deficiencies identified in order for the FDA to reconsiderletter, or withdraw the application. Even with submission of this additional information, the FDA ultimately may decide that the application does not satisfy the regulatory criteria for approval. If and when those conditions have been met to the FDA’s satisfaction, the FDA will typically issue an approval letter. An approval letter authorizes commercial marketing of the drug or biologic with specific prescribing information for specific indications.

Even if the FDA approves a product, it may limit the approved indications for use of the product, require that contraindications, warnings or precautions be included in the product labeling, require that post-approval studies, including Phasephase 4 clinical trials, be conducted to further assess a drug’sproduct’s safety after approval, require testing and surveillance programs to monitor the product after commercialization, or impose other conditions, including distribution and use restrictions or other risk management mechanisms under a REMS, which can materially affect the potential market and profitability of the product. The FDA may prevent or limit further marketing of a product based on the results of post-marketing studies or surveillance programs. After approval, some types of changes to the approved product, such as adding new indications, manufacturing changes, and additional labeling claims, are subject to further testing requirements and FDA review and approval.

Post-Approval Requirements

Drugs and biologics manufactured or distributed pursuant to FDA approvals and licenses are subject to pervasive and continuing regulation by the FDA and other government authorities, including, among other things, requirements relating to recordkeeping, periodic reporting, product sampling and distribution, advertising and promotion and reporting of adverse experiences with the product. After approval, most changes to the approved product, such as adding new indications or other labeling claims are subject to prior FDA review and approval.

There also are continuing, annual program fee requirements for any marketed products.

The FDA may impose a number of post-approval requirements as a condition of approval of an NDA.NDA or BLA. For example, the FDA may require post-marketing testing, including Phasephase 4 clinical trials, and surveillance to further assess and monitor the product’s safety and effectiveness after commercialization.

In addition, drug and biologics manufacturers and other entities involved in the manufacture and distribution of approved drugs and biologics are required to register their establishments with the FDA and state authorities and are subject to periodic unannounced inspections by the FDA and these state authorities for compliance with cGMP requirements. Changes to the manufacturing process are strictly regulated and often require prior FDA approval before being implemented. FDA regulations also require investigation and correction of any deviations from cGMP requirements and impose reporting and documentation requirements upon the sponsor and any third-party manufacturers that the sponsor may decide to use. Accordingly, manufacturers must continue to expend time, money, and effort in the area of production and quality control to maintain cGMP compliance.

Once an approval is granted, the FDA may withdraw the approval if compliance with regulatory requirements and standards is not maintained or if problems occur after the product reaches the market.

Later discovery of previously unknown problems with a product, including adverse events of unanticipated severity or frequency, or with manufacturing processes, or failure to comply with regulatory requirements, may result in mandatory revisions to the approved labeling to add new safety information; imposition of post-market studies or clinical trials to assess new safety risks; or imposition of distribution or other restrictions under a REMS program.

Other potential consequences include, among other things:

The FDA strictly regulates marketing, labeling, advertising and promotion of products that are placed on the market. Drugs and biologics may be promoted only for the approved indications and in accordance with the provisions of the approved label. The FDA and other authorities actively enforce the laws and regulations prohibiting the promotion ofoff-label uses, and a company that is found to have improperly promotedoff-label uses may be subject to significant liability.