Albireo Pharma (ALBO) 10-Q 9 May 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2019	May 01, 2019
Document And Entity Information [Abstract]
Entity Registrant Name	Albireo Pharma, Inc.
Entity Central Index Key	0001322505
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Type	10-Q
Document Period End Date	Mar. 31, 2019
Entity Current Reporting Status	Yes
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Trading Symbol	albo
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		12,039,305

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 150,339	$ 163,885
Prepaid expenses and other assets	1,194	850
Other receivables	2,803	2,915
Total current assets	154,336	167,650
Property and equipment, net	173	187
Goodwill	17,260	17,260
Other noncurrent assets	1,209	369
Total assets	172,978	185,466
Current liabilities:
Trade payables	2,987	4,352
Accrued expenses	6,385	8,165
Other liabilities	569	308
Total current liabilities	9,941	12,825
Liability related to sale of future royalties	51,433	49,969
Long-term liabilities	213	35
Total liabilities	61,587	62,829
Stockholders' Equity:
Common stock, $0.01 par value per share - 30,000,000 authorized at March 31, 2019 and December 31, 2018; 12,038,836 and 11,969,928 issued and outstanding at March 31, 2019 and December 31, 2018	120	120
Additional paid in capital	217,807	214,694
Accumulated other comprehensive income	6,591	4,293
Accumulated deficit	(113,127)	(96,470)
Total stockholders' equity	111,391	122,637
Total liabilities and stockholders' equity	$ 172,978	$ 185,466

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	30,000,000	30,000,000
Common stock, shares issued	12,038,836	11,969,928
Common stock, shares outstanding	12,038,836	11,969,928

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Revenue	$ 570	$ 11,202
Operating expenses:
Research and development	8,329	6,151
General and administrative	5,293	4,128
Other operating (income) expense, net	2,296	1,504
Total operating expenses	15,918	11,783
Operating loss	(15,348)	(581)
Interest income (expense), net	(1,309)	(1,016)
Non-operating income (expense), net		(22)
Net loss before income taxes	(16,657)	(1,619)
Income tax	0	0
Net loss	$ (16,657)	$ (1,619)
Net loss per share attributable to holders of common stock:
Net loss per share - basic and diluted	$ (1.39)	$ (0.15)
Weighted-average shares outstanding:
Weighted average shares outstanding - basic and diluted	12,001,125	10,896,575

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (16,657)	$ (1,619)
Other comprehensive loss:
Foreign currency translation adjustment	2,298	1,194
Total other comprehensive income (loss)	2,298	1,194
Total comprehensive income (loss)	$ (14,359)	$ (425)

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity 10K - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income	Accumulated Deficit	Total
Balance at beginning of period at Dec. 31, 2017	$ 89	$ 114,522	$ 1,001	$ (50,359)	$ 65,253
Balance (in shares) at Dec. 31, 2017	8,902,784
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share based compensation expense		1,188			1,188
Exercise of options
Exercise of options (in shares)
Issuance of common stock, net of costs	$ 30	94,120			94,150
Issuance of common stock (in shares)	2,994,362
Other comprehensive loss			1,194		1,194
Net loss				(1,619)	(1,619)
Balance at end of period at Mar. 31, 2018	$ 119	209,830	2,195	(51,978)	160,166
Balance (in shares) at Mar. 31, 2018	11,897,146
Balance at beginning of period at Dec. 31, 2018	$ 120	214,694	4,293	(96,470)	122,637
Balance (in shares) at Dec. 31, 2018	11,969,928
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share based compensation expense		1,823			1,823
Exercise of options		1,290			$ 1,290
Exercise of options (in shares)	68,908				68,908
Exercise of warrants
Exercise of warrants, shares
Issuance of common stock, net of costs
Issuance of common stock (in shares)
Other comprehensive loss			2,298		2,298
Net loss				(16,657)	(16,657)
Balance at end of period at Mar. 31, 2019	$ 120	$ 217,807	$ 6,591	$ (113,127)	$ 111,391
Balance (in shares) at Mar. 31, 2019	12,038,836

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities:
Net loss	$ (16,657)	$ (1,619)
Adjustments to reconcile net loss to net cash used in operating activities:
Non cash interest expense on liability related to royalty monetization	2,005	1,007
Depreciation and amortization	11	53
Stock-based compensation expense	1,823	1,188
Unrealized foreign exchange (gain) loss	3,441	1,200
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(354)	401
Other receivables	28	(738)
Other non current assets	(440)	332
Trade payables	(1,262)	924
Accrued expenses	(1,619)	(1,581)
Other liabilities and long-term liabilities	(499)	(69)
Net cash (used in) provided by operating activities	(13,523)	1,098
Cash flows from investing activities:
Purchase of property, plant and equipment		(47)
Net cash used in investing activities		(47)
Cash flows from financing activities:
Proceeds from issuance of common stock, net of issuance costs		94,150
Royalty monetization agreement		44,525
Exercise of options	1,290
Net cash provided by financing activities	1,290	138,675
Effect of exchange rate changes on cash and cash equivalents	(1,313)	(41)
Net (decrease) increase in cash and cash equivalents	(13,546)	139,685
Cash and cash equivalents - beginning of period	163,885	53,231
Cash and cash equivalents - end of period	150,339	$ 192,916
Supplemental disclosures of cash flow information:
Right of use asset	1,205
Lease liability	$ 1,190

Summary of Significant Accounti

Summary of Significant Accounting Policies and Basis of Presentation	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Summary of Significant Accounting Policies and Basis of Presentation	1. Summary of significant accounting policies and basis of presentation Organization Albireo Pharma, Inc. (Parent), together with its direct and indirect subsidiaries (the Company), is a clinical-stage biopharmaceutical company focused on the development and commercialization of novel bile acid modulators to treat orphan pediatric liver diseases and other liver and gastrointestinal diseases and disorders. The Company’s clinical pipeline includes a Phase 3 lead product, a Phase 2 product candidate, and elobixibat, which is approved in Japan for the treatment of chronic constipation. Odevixibat, the Company’s Phase 3 lead product, is in development initially for the treatment of patients with progressive familial intrahepatic cholestasis (PFIC), a rare, life-threatening genetic disorder affecting young children. Basis of presentation The accompanying unaudited Condensed Consolidated Financial Statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information, and the instructions to Form 10‑Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the audited consolidated financial statements and accompanying notes included in our Annual Report on Form 10‑K for the fiscal year ended December 31, 2018. In the opinion of management, all adjustments (including normal recurring accruals) considered necessary for fair presentation have been included in the Condensed Consolidated Financial Statements. The results of operations for the three months ended March 31, 2019 are not necessarily indicative of the results that may be expected for the full fiscal year, any other interim period or any future fiscal year. The condensed consolidated financial statements are prepared on a basis consistent with prior periods except for the adoption of the new leasing standard discussed below. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (ASC) and Accounting Standards Update (ASU) of the Financial Accounting Standards Board (FASB). Principles of consolidation The accompanying Consolidated Financial Statements include the accounts of Parent and its direct or indirect wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. Foreign currency translation Functional and presentation currency Items included in the financial statements of each entity comprising the Company are measured using the currency of the primary economic environment in which the entity operates (the functional currency). Transactions and balances Foreign currency transactions in each entity comprising the Company are remeasured into the functional currency of the entity using the exchange rates prevailing at the respective transaction dates. Foreign exchange gains and losses resulting from the settlement of such transactions and from the remeasurement at year-end exchange rates of monetary assets and liabilities denominated in foreign currencies are recognized within Other operating (income) expense, net in the Condensed Consolidated Statements of Operations. The results and financial position of the Company that have a functional currency different from the USD are translated into the presentation currency as follows: a. assets and liabilities presented are translated at the closing exchange rate as of March 31, 2019 and December 31, 2018; b. income and expenses for each statement of comprehensive income (loss) are translated at the average exchange rate for the applicable period; and c. significant transactions use the closing exchange rate on the date of the transaction; All resulting exchange differences arising from such translations are recognized directly in other comprehensive income (loss) and presented as a separate component of equity. Use of estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts of assets, liabilities, revenues and expenses reported in the financial statements and accompanying notes. Management must apply significant judgment in this process. On an ongoing basis, the Company evaluates its estimates and assumptions, including but not limited to accruals, deferred tax assets and the accretion of interest on the monetization liability. Actual results could materially differ from these estimates. Research and development expenses Research and development costs are expensed as incurred and include primarily salaries, benefits and other staff-related costs; clinical trial and related clinical manufacturing costs; contract services and other outside costs. The Company’s nonclinical studies and clinical trials are performed by third-party contract research organizations (CROs). Some of these expenses are billed monthly for services performed, while others are billed based upon milestones achieved. For nonclinical studies, the significant factors used in estimating accruals include the percentage of work completed to date and contract milestones achieved. For clinical trial expenses, the significant factors used in estimating accruals include the number of patients enrolled and percentage of work completed to date or contract milestones achieved. The Company’s estimates are highly dependent upon the timeliness and accuracy of the data provided by the respective CROs regarding the status of the contracted activity, with adjustments made when deemed necessary. Revenue recognition The Company enters into licensing agreements which are within the scope of ASC Topic 606, Revenue from Contracts with Customers (ASC 606), under which it may exclusively license rights to research, develop, manufacture and commercialize its product candidates to third parties. The terms of these arrangements may include payment to the Company of one or more of the following: non-refundable, upfront license fees; reimbursement of certain costs; development, regulatory and commercial milestone payments; and royalties on net sales of licensed products. In determining the appropriate amount of revenue to be recognized as the Company fulfills its obligations under each of its agreements, the Company performs the following steps: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations, including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. As part of the accounting for these arrangements, the Company must use significant judgment to determine: (a) the number of performance obligations based on the determination under step (ii) above and (b) the transaction price under step (iii) above. The Company uses judgment to determine whether milestones or other variable consideration, except for royalties, should be included in the transaction price as described further below. The transaction price is allocated to each performance obligation on a relative stand-alone selling price basis, for which the Company recognizes revenue as or when the performance obligations under the contract are satisfied. Amounts received prior to revenue recognition are recorded as deferred revenue. Amounts expected to be recognized as revenue within the 12 months following the balance sheet date are classified as current portion of deferred revenue in the accompanying consolidated balance sheets. Amounts not expected to be recognized as revenue within the 12 months following the balance sheet date are classified as deferred revenue, net of current portion. Exclusive Licenses If the license to the Company’s intellectual property is determined to be distinct from the other promises or performance obligations identified in the arrangement, the Company recognizes revenue from non-refundable, upfront fees allocated to the license when the license is transferred to the customer and the customer is able to use and benefit from the license. In assessing whether a promise or performance obligation is distinct from the other promises, the Company considers factors such as the research, development, manufacturing and commercialization capabilities of the collaboration partner and the availability of the associated expertise in the general marketplace. In addition, the Company considers whether the collaboration partner can benefit from a promise for its intended purpose without the receipt of the remaining promise, whether the value of the promise is dependent on the unsatisfied promise, whether there are other vendors that could provide the remaining promise, and whether it is separately identifiable from the remaining promise. For licenses that are combined with other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. The measure of progress, and thereby periods over which revenue should be recognized, are subject to estimates by management and may change over the course of the research and development and licensing agreement. Such a change could have a material impact on the amount of revenue the Company records in future periods. Milestone Payments At the inception of each arrangement that includes development milestone payments, the Company evaluates whether the milestones are considered probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. The Company evaluates factors such as the scientific, clinical, regulatory, commercial, and other risks that must be overcome to achieve the particular milestone in making this assessment. There is considerable judgment involved in determining whether it is probable that a significant revenue reversal would not occur. At the end of each subsequent reporting period, the Company reevaluates the probability of achievement of all milestones subject to constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment. Royalties For arrangements that include sales-based royalties, including milestone payments based on a level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). In 2012, the Company entered into a license agreement (the Agreement) with EA Pharma Co., Ltd. (EA Pharma, formerly Ajinomoto Pharmaceuticals Co., Ltd.) to develop a select product candidate (elobixibat) for registration and subsequent commercialization in select markets. In conjunction with the Agreement, the Company granted EA Pharma an exclusive license to its intellectual property for development and commercialization activities in the designated field and territories. The Company is entitled to payments resulting from pharmaceutical ingredient or related procurement services if provided as part of a development plan. Revenue related to these payments is recorded on a net basis; in this instance, the Company acts as an agent, as it does not have discretion to change suppliers and does not perform any part of the services or manufacture of the subject pharmaceutical ingredients. The costs associated with these activities are netted against the related revenue in the condensed consolidated statements of operations. As of March 31, 2019, the Company is eligible to receive a regulatory-based milestone payment under the Agreement of €4.3 million ($4.8 million based on the Euro to USD exchange rate as of March 31, 2019) if a specified regulatory event is achieved for elobixibat. The cash payments and any other payments for milestones and royalties from EA Pharma are non-refundable, non-creditable and not subject to set-off The Agreement will continue until the last royalty period for any product in the territory, which is defined as the period when there are no remaining patent rights or regulatory exclusivity in place for any products subject to royalties. EA Pharma may terminate the Agreement at will upon 180 days’ prior written notice to the Company. Either party may terminate the Agreement for the other party’s uncured material breach or insolvency and in certain other circumstances agreed to by the parties. The Company assessed this arrangement in accordance with Accounting Standards Codification and concluded that the contract counterparty, EA Pharma, is a customer. The Company identified the following material promises under the arrangement: (1) a sub-licensable and exclusive license to use the Company’s intellectual property and collaboration compounds to conduct development and commercialization activities in the designated fields and territories and (2) the technology transfer of the Albireo intellectual property and compound. Participation on the joint development committee (“JDC”) and joint commercialization committee (“JCC”) was determined to be quantitatively and qualitatively immaterial and therefore is excluded from the performance obligations. The license was determined to not be distinct from the technology transfer; as such, the Company determined that these promises should be combined into a single performance obligation. Under the Agreement, in order to evaluate the appropriate transaction price, the Company determined that the upfront amount constituted the entirety of the consideration to be included in the transaction price as of the outset of the arrangement, which was allocated to the single performance obligation. At the outset of the arrangement, the transaction price included only the €10.0 million upfront consideration received and was increased to include the $8.0 million received in conjunction with the 2016 amendment to the agreement. The potential milestone payments were excluded from the transaction price, as all milestone amounts were either fully constrained or related to future sales-based royalties. In April 2013, December 2015, and October 2016, various development milestone events were achieved, and the Company recognized revenue related to these events; because the Company previously satisfied its performance obligation to deliver the license, the Company recorded these milestone payments as received. The Company will reevaluate the transaction price at the end of each reporting period and as other uncertain events are resolved or other changes in circumstances occur, and, if necessary, adjust its estimate of the transaction price. In January 2018, the Japanese Ministry of Health Labour and Welfare (MHLW) approved a new drug application filed by EA Pharma for elobixibat for the treatment of chronic constipation, for which the Company received a milestone payment of $11.2 million. Based on the regulatory approval, the Company determined that the milestone was no longer at risk of significant reversal. As such, because the single performance obligation had previously been satisfied, the Company recognized this amount in full in the first quarter of 2018 and there was no deferred revenue or contract asset as of December 31, 2018. The Company recognizes the royalty revenue based on the estimated qualifying sales by EA Pharma each period. Monetization of Future Royalties In December 2017, the Company entered into a royalty interest acquisition agreement (RIAA) with HealthCare Royalty Partners III, L.P. (HCR) pursuant to which it sold to HCR the right to receive all royalties from sales in Japan and sales milestones achieved from any covered territory potentially payable to the Company under the Agreement, up to a specified maximum “cap” amount of $78.8 million, based on the funds the Company received from HCR to date. The Company received $44.5 million from HCR, net of certain transaction expenses, under the RIAA and the Company is eligible to receive an additional $15.0 million under the RIAA if a specified sales milestone is achieved for elobixibat in Japan. If the cap amount is reached, the Company will again become eligible to receive royalties from Japanese sales and sales milestones from covered territories for elobixibat from EA Pharma under the Agreement. The Company is obligated to make royalty interest payments to HCR under the RIAA only to the extent it receives future Japanese royalties, sales milestones or other specified payments from EA Pharma. Although the Company sold its rights to receive royalties from the sales of elobixibat in Japan, as a result of its ongoing involvement in the cash flows related to these royalties, the Company will continue to account for these royalties as revenue. The Company recorded the $44.5 million as a liability related to sale of future royalties (royalty obligation). The royalty obligation will be amortized using the effective interest rate method, based on the Company’s best estimate of the time it will take to reach the capped amount. The following table shows the activity within the liability account for the period ended March 31, 2019: March 31, 2019 (in thousands) Liability related to sale of future royalties—beginning balance $ 50,546 Foreign currency translation (gain)/loss in other comprehensive income/(loss) 16 Accretion of interest expense on liability related to royalty monetization Repayment of the liability (564) Liability related to sale of future royalties—ending balance $ 52,003 Less current portion classified within other current liabilities (570) Net ending liability related to sale of future royalties $ 51,433 The Company records estimated royalties due for the current period in accrued other until the payment is received from EA Pharma at which time the Company then remits payment to HCR. As royalties are remitted to HCR, the balance of the royalty obligation will be effectively repaid over the life of the RIAA. In order to determine the amortization of the royalty obligation, the Company is required to estimate the total amount of future royalty payments to be received and submitted to HCR, as noted above, based on the Company’s best estimate of the time it will take to reach the cap amount and when milestones will be received. The sum of these amounts less the $44.5 million proceeds the Company received will be recorded as interest expense over the life of the royalty obligation. Since inception, the Company’s estimate of its total interest expense resulted in a quarterly effective interest rate of approximately 4.02% The Company periodically assesses the estimated royalty payments to HCR and to the extent such payments are greater or less than its initial estimates or the timing of such payments is materially different than its original estimates, the Company will prospectively adjust the accretion of interest on the royalty obligation. There are a number of factors that could materially affect the amount and the timing of royalty payments, most of which are not within the Company’s control. Such factors include, but are not limited to, the rate of elobixibat prescriptions, the number of doses administered, the introduction of competing products, manufacturing or other delays, patent protection, adverse events that result in governmental health authority imposed restrictions on the use of the drug products, significant changes in foreign exchange rates as the royalties remitted to HCR are in U.S. dollars while sales of elobixibat are in Japanese yen, and sales never achieving forecasted numbers, which would result in reduced royalty payments and reduced non-cash interest expense over the life of the royalty obligation. To the extent future royalties result in an amount less than the liability, the Company is not obligated to fund any such shortfall. Loss contingencies Loss contingencies are recorded as liabilities when it is probable that a liability has occurred and the amount of loss is reasonably estimable. Disclosure is required when there is a reasonable possibility that an ultimate loss will be material. Contingent liabilities are often resolved over long periods of time. Estimating probable losses requires analysis that often depends on judgments about potential actions by third parties, such as regulators. Recently adopted accounting pronouncements As of January 1, 2019, the Company adopted ASU 2016‑02, “ Leases (Topic 842) .” The new standard establishes a right-of-use (ROU) model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. The Company has applied the transition provisions at the beginning of the period of adoption, which results in recording the cumulative adjustment to the opening balance sheet as of January 1, 2019. Under this transition provision, the Company will continue to apply the legacy guidance under ASC 840, Leases , including its disclosure requirements, in the comparative periods presented in fiscal 2019. On the date of the adoption, the Company recorded an ROU of $1.2 million and lease liabilities of $1.2 million. Additionally, the Company elected the following practical expedients: the Company has elected to not separate lease components from non-lease components in its lease contract; the Company will not apply the recognition requirements of ASC 842 to its leases with lease terms of 12 months or less but rather recognize the lease expense on a straight-line basis over the lease term; Relief package – the Company has not reassessed whether expired or existing contracts may contain a lease, the lease classification of expired or existing leases and whether previously capitalized indirect costs would qualify for capitalization under ASC 842. Use of hindsight – the Company has elected to use hindsight in assessing the likelihood of renewals, terminations and purchase options and in assessing impairment of ROU assets . Portfolio approach – the Company has elected to not apply the portfolio approach for groups of leases with similar characteristics.

Fair Value of financial instrum

Fair Value of financial instruments	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value of Financial instruments	2. Fair Value of financial instruments When measuring the fair value of financial instruments, the Company evaluates valuation techniques such as the market approach, the income approach and the cost approach. A three-level valuation hierarchy, which prioritizes the inputs to valuation techniques that are used to measure fair value, is based upon whether such inputs are observable or unobservable. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect market assumptions made by the reporting entity. The three-level hierarchy for the inputs to valuation techniques is briefly summarized as follows: Level 1—Observable inputs such as quoted prices (unadjusted) for identical instruments in active markets; Level 2—Observable inputs such as quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, or model-derived valuations whose significant inputs are observable for substantially the full term of the assets or liabilities; and Level 3—Unobservable inputs that reflect the reporting entity’s estimate of assumptions that market participants would use in pricing the asset or liability.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	3.Commitments and contingencies Commercial real estate leases The Company’s portfolio of commercial real estate leases consists of office space for its corporate headquarters in Boston, Massachusetts and for administrative and research lab space in Goteborg, Sweden, both of which are accounted for as operating leases. These leases include renewal rights as for the corporate headquarters lease, escalating payments. On March 28, 2019, the Company entered into an amendment to the Boston, Massachusetts lease to (i) replace the Company’s existing office space with a new office space that will be leased from the same landlord and (ii) extend the term of the lease through the date ending eighty-eight months after the date upon which the landlord will have substantially completed the work necessary to deliver the new leased space. The Company is expected to take control of the new leased space in the third quarter of 2019. The new leased space will contain monthly lease payments subject to annual escalations of $1.00 per square foot for the remaining term of the new lease with the Company obligated to make approximately $7.3 million of aggregate lease payments over the term of the new lease, or approximately $900,000 annually. The new leased space was excluded from the Right of Use Asset and Lease Liability because the Company does not yet have possession of the space. The Company’s lease in Goteborg, Sweden includes the rental of office and lab space plus a defined number of parking spaces and contained an original expiration date in November 2019. This lease includes annual rent escalations based on the changes in the Swedish Consumer Price Index. This lease renews automatically for consecutive three year terms unless notice of non-renewal is given by either party at least nine months prior to the end of the current term and subject to the Company’s right to terminate the lease at any time upon six months’ notice. Subsequent to the year ended December 31, 2018, this lease was renewed for an additional three year period through November 2022, with quarterly payments of $35,419. As of March 31, 2019, the net balance of ROU assets totaled $400,000 and were classified within other non current assets. The current and long term balances of lease liabilities at March 31, 2019 were $174,000 and $213,000, respectively, and were classified within other liabilities, and long-term liabilities, respectively. Operating lease expense under ASC 842 was $103,000 for the three months ended March 31, 2019. There were no short-term lease or variable lease costs incurred for the three months ended March 31, 2019. As of March 31, 2019, the weighted average remaining lease term for the Company’s operating leases was 2.6 years. Rent expense recognized under legacy GAAP for the Company’s operating leases was $102,000 for the three months ended March 31, 2018. Agreements with CROs As of March 31, 2019, the Company had various agreements with CROs for the conduct of specified research and development activities. Based on the terms of the respective agreements, the Company may be required to make future payments of up to $23.1 million to CROs upon the completion of contracted work. Legal Contingency On February 19, 2019, the Company filed a complaint for breach of contract and breach of implied covenant of good faith and fair dealing against Ferring International Center S.A. (the “Respondent”) in the United States District Court for the Southern District of New York. Based on procedural considerations, we decided to refile the complaint in the Supreme Court of the State of New York, County of New York on April 26, 2019. We previously entered into the License Agreement, dated July 2, 2012, as amended as of October 2013 (the “License Agreement”), by and between Respondent and us, pursuant to which Respondent, among other things, conducted two Phase 3 clinical trials to evaluate the efficacy and safety of elobixibat as a treatment for chronic idiopathic constipation, known as Echo 1 and Echo 2, which ended in 2014. As previously disclosed, Respondent stopped Echo 1 and Echo 2 early citing an issue related to the distribution of study drug to study sites that was unrelated to the performance of elobixibat and terminated the License Agreement. The complaint alleges that Respondent breached its obligations under the License Agreement to (1) make earned milestone payments, (2) use good clinical practices, good laboratory practices and good manufacturing practices, and (3) use commercially reasonable efforts. The complaint also alleges that Respondent violated the covenant of good faith and fair dealing implied in the License Agreement. In the complaint, the Company is seeking, among other things, compensatory damages of at least € 37 million. The Company has retained outside counsel under a contingency fee arrangement, and as a result, the Company will not incur attorneys’ fees for litigating the matter, but counsel will receive a contingent fee of 33 1/3% of the net recovery (after deduction of expenses) in the event a recovery is received. Due to their nature, it is difficult to predict the outcome, or the costs involved in any litigation. Furthermore, Respondent may have significant resources and interest to litigate and therefore, although we have a contingency fee arrangement, this litigation could be protracted and may ultimately involve significant legal expenses.

Net Loss Per Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Net Loss Per Share	4. Net loss per share Basic net loss per share, or Basic EPS, is calculated by dividing the net loss by the weighted average number of shares of common stock outstanding. Diluted net loss per share, or Diluted EPS, is calculated by dividing the net loss by the weighted-average number of shares of common stock plus dilutive common stock equivalents outstanding. The following table sets forth the computation of Basic EPS and Diluted EPS (in thousands, except for share and per share data): Three Months Ended March 31, 2019 2018 Basic and Diluted EPS: Numerator Net loss $ (16,657) $ (1,619) Denominator Weighted average number of shares outstanding 12,001,125 10,896,575 Basic and Diluted EPS $ (1.39) $ (0.15) The following outstanding common stock equivalents were excluded from the computation of Diluted EPS for the three months ended March 31, 2019 and 2018 because including them would have been anti-dilutive: For the Three Months Ended March 31, 2019 2018 Options to purchase common stock and RSUs 1,757,728 703,016

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income taxes	5. Income taxes The Company did not record a tax provision or benefit for the three months ended March 31, 2019 or 2018. The Company has continued to maintain a full valuation allowance against its net deferred tax assets. The Company has had an overall net operating loss position since its inception.

Financings

Financings	3 Months Ended
	Mar. 31, 2019
Equity [Abstract]
Financings	6. Financings At-the-Market Offering Program In October 2017, the Company entered into an at-the-market offering program, which we refer to as the 2017 Sales Agreement relating to the sale of shares of the Company’s common stock having an aggregate offering price of up to $50.0 million. In February 2018, the Company sold an aggregate of 728,862 shares of common stock pursuant to the 2017 Sales Agreement and received proceeds, net of offering expenses, of approximately $24.2 million. On March 6, 2019, we terminated the 2017 Sales Agreement and we entered into a new sales agreement, which we refer to as the 2019 Sales Agreement, with respect to an at-the-market offering program relating to the sale of shares of the Company’s common stock having an aggregate offering price of up to $50.0 million. January 2018 Underwritten Public Offering On January 9, 2018, the Company completed an underwritten public offering of 2,265,500 shares of its common stock, at a price to public of $33.00 per share. The Company received net proceeds from this offering of $69.9 million, after deducting underwriting discounts, commission and offering expenses.

Stock-based Compensation

Stock-based Compensation	3 Months Ended
	Mar. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-based Compensation	7. Stock-based Compensation The Company recognized stock-based compensation expense for employees of $1.8 million and $1.2 million for the three months ended March 31, 2019 and 2018, respectively. A summary of the outstanding stock options as of March 31, 2019 is as follows: Stock Options Outstanding Weighted- Weighted- Average Average Remaining Aggregate Exercise Contractual Intrinsic Number of Price Per Term Value (in Shares Share (Years) thousands) Outstanding—December 31, 2018 1,369,504 $ 22.34 8.06 $ 8,421 Granted 413,461 $ 24.46 Expirations/forfeitures (13,329) $ 55.64 Exercises (68,908) $ 18.73 Outstanding—March 31, 2019 1,700,728 $ 22.74 8.32 $ 17,066 Exercisable—March 31, 2019 536,836 $ 14.87 6.49 $ 10,225 Aggregate intrinsic value represents the difference between the estimated fair value of the underlying common stock and the exercise price of outstanding, in-the-money options. Options to purchase 19,422 shares of common stock are performance based and vest upon the date the Company files a drug approval application for its product candidate odevixibat for any orphan indication, if such filing occurs prior to a specified date. This unvested performance-based option is excluded from the vested or expected to vest balance as of March 31, 2019. As of March 31, 2019, the total unrecognized compensation expense related to unvested options was $19.7 million, which the Company expects to recognize over a weighted average vesting period of 2.8 years. In determining the estimated fair value of the stock-based awards, the Company uses the Black-Scholes option pricing model and assumptions discussed below. Each of these inputs is subjective and generally requires significant judgment to determine. The fair value of stock option awards granted during the three months ended March 31, 2019 was estimated with the following assumptions: Three Months Ended March 31, 2019 Price per share of common stock $ 22.22 - 28.76 Expected term (in years) 5.6 - 5.6 Risk-free interest rate 2.2 - 2.6 Expected volatility 87.6 - 88.1 Dividend rate 0% Restricted Stock Units The Company grants restricted stock units (“RSUs”) to executive officers and employees from time to time. Each RSU award represents one share of common stock and each award vests 25% on the first anniversary and in equal quarterly installments thereafter. The costs of the awards, determined as the fair market value of the shares on the grant date, are expensed on a straight-lined basis over the length of the award. A summary of outstanding RSU as of March 31, 2019 is as follows: Shares Weighted Non-vested and outstanding balance at December 31, 2018 $ Changes during the period: RSUs granted Non-vested and outstanding RSU balance at March 31, 2019 $ Employee Stock Purchase Plan In June of 2018, the Company’s Board of Directors adopted the 2018 Employee Stock Purchase Plan (the Plan) that allows eligible employees to purchase shares of its common stock at a discount through payroll deductions. The Plan was subsequently approved by shareholders, with 300,000 shares being available to be issued under the Plan. The Plan terms state implementation will be by a series of six-month offering periods, with a new offering period commencing on June 1 and December 1 of each year or the first business day thereafter. The initial Offering Period under the Plan began on December 1, 2018 and will close on May 31, 2019. The Plan is intended to qualify under the Internal Revenue Code of 1986, Section 423

Summary of Significant Accoun_2

Summary of Significant Accounting Policies and Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Basis of Presentation	Basis of presentation The accompanying unaudited Condensed Consolidated Financial Statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information, and the instructions to Form 10‑Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the audited consolidated financial statements and accompanying notes included in our Annual Report on Form 10‑K for the fiscal year ended December 31, 2018. In the opinion of management, all adjustments (including normal recurring accruals) considered necessary for fair presentation have been included in the Condensed Consolidated Financial Statements. The results of operations for the three months ended March 31, 2019 are not necessarily indicative of the results that may be expected for the full fiscal year, any other interim period or any future fiscal year. The condensed consolidated financial statements are prepared on a basis consistent with prior periods except for the adoption of the new leasing standard discussed below. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (ASC) and Accounting Standards Update (ASU) of the Financial Accounting Standards Board (FASB).
Principles of Consolidation	Principles of consolidation The accompanying Consolidated Financial Statements include the accounts of Parent and its direct or indirect wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.
Foreign Currency Translation	Foreign currency translation Functional and presentation currency Items included in the financial statements of each entity comprising the Company are measured using the currency of the primary economic environment in which the entity operates (the functional currency). Transactions and balances Foreign currency transactions in each entity comprising the Company are remeasured into the functional currency of the entity using the exchange rates prevailing at the respective transaction dates. Foreign exchange gains and losses resulting from the settlement of such transactions and from the remeasurement at year-end exchange rates of monetary assets and liabilities denominated in foreign currencies are recognized within Other operating (income) expense, net in the Condensed Consolidated Statements of Operations. The results and financial position of the Company that have a functional currency different from the USD are translated into the presentation currency as follows: a. assets and liabilities presented are translated at the closing exchange rate as of March 31, 2019 and December 31, 2018; b. income and expenses for each statement of comprehensive income (loss) are translated at the average exchange rate for the applicable period; and c. significant transactions use the closing exchange rate on the date of the transaction; All resulting exchange differences arising from such translations are recognized directly in other comprehensive income (loss) and presented as a separate component of equity.
Use of Estimates	Use of estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts of assets, liabilities, revenues and expenses reported in the financial statements and accompanying notes. Management must apply significant judgment in this process. On an ongoing basis, the Company evaluates its estimates and assumptions, including but not limited to accruals, deferred tax assets and the accretion of interest on the monetization liability. Actual results could materially differ from these estimates.
Research and Development Expenses	Research and development expenses Research and development costs are expensed as incurred and include primarily salaries, benefits and other staff-related costs; clinical trial and related clinical manufacturing costs; contract services and other outside costs. The Company’s nonclinical studies and clinical trials are performed by third-party contract research organizations (CROs). Some of these expenses are billed monthly for services performed, while others are billed based upon milestones achieved. For nonclinical studies, the significant factors used in estimating accruals include the percentage of work completed to date and contract milestones achieved. For clinical trial expenses, the significant factors used in estimating accruals include the number of patients enrolled and percentage of work completed to date or contract milestones achieved. The Company’s estimates are highly dependent upon the timeliness and accuracy of the data provided by the respective CROs regarding the status of the contracted activity, with adjustments made when deemed necessary.
Revenue recognition	Revenue recognition The Company enters into licensing agreements which are within the scope of ASC Topic 606, Revenue from Contracts with Customers (ASC 606), under which it may exclusively license rights to research, develop, manufacture and commercialize its product candidates to third parties. The terms of these arrangements may include payment to the Company of one or more of the following: non-refundable, upfront license fees; reimbursement of certain costs; development, regulatory and commercial milestone payments; and royalties on net sales of licensed products. In determining the appropriate amount of revenue to be recognized as the Company fulfills its obligations under each of its agreements, the Company performs the following steps: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations, including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. As part of the accounting for these arrangements, the Company must use significant judgment to determine: (a) the number of performance obligations based on the determination under step (ii) above and (b) the transaction price under step (iii) above. The Company uses judgment to determine whether milestones or other variable consideration, except for royalties, should be included in the transaction price as described further below. The transaction price is allocated to each performance obligation on a relative stand-alone selling price basis, for which the Company recognizes revenue as or when the performance obligations under the contract are satisfied. Amounts received prior to revenue recognition are recorded as deferred revenue. Amounts expected to be recognized as revenue within the 12 months following the balance sheet date are classified as current portion of deferred revenue in the accompanying consolidated balance sheets. Amounts not expected to be recognized as revenue within the 12 months following the balance sheet date are classified as deferred revenue, net of current portion. Exclusive Licenses If the license to the Company’s intellectual property is determined to be distinct from the other promises or performance obligations identified in the arrangement, the Company recognizes revenue from non-refundable, upfront fees allocated to the license when the license is transferred to the customer and the customer is able to use and benefit from the license. In assessing whether a promise or performance obligation is distinct from the other promises, the Company considers factors such as the research, development, manufacturing and commercialization capabilities of the collaboration partner and the availability of the associated expertise in the general marketplace. In addition, the Company considers whether the collaboration partner can benefit from a promise for its intended purpose without the receipt of the remaining promise, whether the value of the promise is dependent on the unsatisfied promise, whether there are other vendors that could provide the remaining promise, and whether it is separately identifiable from the remaining promise. For licenses that are combined with other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. The measure of progress, and thereby periods over which revenue should be recognized, are subject to estimates by management and may change over the course of the research and development and licensing agreement. Such a change could have a material impact on the amount of revenue the Company records in future periods. Milestone Payments At the inception of each arrangement that includes development milestone payments, the Company evaluates whether the milestones are considered probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. The Company evaluates factors such as the scientific, clinical, regulatory, commercial, and other risks that must be overcome to achieve the particular milestone in making this assessment. There is considerable judgment involved in determining whether it is probable that a significant revenue reversal would not occur. At the end of each subsequent reporting period, the Company reevaluates the probability of achievement of all milestones subject to constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment. Royalties For arrangements that include sales-based royalties, including milestone payments based on a level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). In 2012, the Company entered into a license agreement (the Agreement) with EA Pharma Co., Ltd. (EA Pharma, formerly Ajinomoto Pharmaceuticals Co., Ltd.) to develop a select product candidate (elobixibat) for registration and subsequent commercialization in select markets. In conjunction with the Agreement, the Company granted EA Pharma an exclusive license to its intellectual property for development and commercialization activities in the designated field and territories. The Company is entitled to payments resulting from pharmaceutical ingredient or related procurement services if provided as part of a development plan. Revenue related to these payments is recorded on a net basis; in this instance, the Company acts as an agent, as it does not have discretion to change suppliers and does not perform any part of the services or manufacture of the subject pharmaceutical ingredients. The costs associated with these activities are netted against the related revenue in the condensed consolidated statements of operations. As of March 31, 2019, the Company is eligible to receive a regulatory-based milestone payment under the Agreement of €4.3 million ($4.8 million based on the Euro to USD exchange rate as of March 31, 2019) if a specified regulatory event is achieved for elobixibat. The cash payments and any other payments for milestones and royalties from EA Pharma are non-refundable, non-creditable and not subject to set-off The Agreement will continue until the last royalty period for any product in the territory, which is defined as the period when there are no remaining patent rights or regulatory exclusivity in place for any products subject to royalties. EA Pharma may terminate the Agreement at will upon 180 days’ prior written notice to the Company. Either party may terminate the Agreement for the other party’s uncured material breach or insolvency and in certain other circumstances agreed to by the parties. The Company assessed this arrangement in accordance with Accounting Standards Codification and concluded that the contract counterparty, EA Pharma, is a customer. The Company identified the following material promises under the arrangement: (1) a sub-licensable and exclusive license to use the Company’s intellectual property and collaboration compounds to conduct development and commercialization activities in the designated fields and territories and (2) the technology transfer of the Albireo intellectual property and compound. Participation on the joint development committee (“JDC”) and joint commercialization committee (“JCC”) was determined to be quantitatively and qualitatively immaterial and therefore is excluded from the performance obligations. The license was determined to not be distinct from the technology transfer; as such, the Company determined that these promises should be combined into a single performance obligation. Under the Agreement, in order to evaluate the appropriate transaction price, the Company determined that the upfront amount constituted the entirety of the consideration to be included in the transaction price as of the outset of the arrangement, which was allocated to the single performance obligation. At the outset of the arrangement, the transaction price included only the €10.0 million upfront consideration received and was increased to include the $8.0 million received in conjunction with the 2016 amendment to the agreement. The potential milestone payments were excluded from the transaction price, as all milestone amounts were either fully constrained or related to future sales-based royalties. In April 2013, December 2015, and October 2016, various development milestone events were achieved, and the Company recognized revenue related to these events; because the Company previously satisfied its performance obligation to deliver the license, the Company recorded these milestone payments as received. The Company will reevaluate the transaction price at the end of each reporting period and as other uncertain events are resolved or other changes in circumstances occur, and, if necessary, adjust its estimate of the transaction price. In January 2018, the Japanese Ministry of Health Labour and Welfare (MHLW) approved a new drug application filed by EA Pharma for elobixibat for the treatment of chronic constipation, for which the Company received a milestone payment of $11.2 million. Based on the regulatory approval, the Company determined that the milestone was no longer at risk of significant reversal. As such, because the single performance obligation had previously been satisfied, the Company recognized this amount in full in the first quarter of 2018 and there was no deferred revenue or contract asset as of December 31, 2018. The Company recognizes the royalty revenue based on the estimated qualifying sales by EA Pharma each period.
Monetization of Future Royalties	Monetization of Future Royalties In December 2017, the Company entered into a royalty interest acquisition agreement (RIAA) with HealthCare Royalty Partners III, L.P. (HCR) pursuant to which it sold to HCR the right to receive all royalties from sales in Japan and sales milestones achieved from any covered territory potentially payable to the Company under the Agreement, up to a specified maximum “cap” amount of $78.8 million, based on the funds the Company received from HCR to date. The Company received $44.5 million from HCR, net of certain transaction expenses, under the RIAA and the Company is eligible to receive an additional $15.0 million under the RIAA if a specified sales milestone is achieved for elobixibat in Japan. If the cap amount is reached, the Company will again become eligible to receive royalties from Japanese sales and sales milestones from covered territories for elobixibat from EA Pharma under the Agreement. The Company is obligated to make royalty interest payments to HCR under the RIAA only to the extent it receives future Japanese royalties, sales milestones or other specified payments from EA Pharma. Although the Company sold its rights to receive royalties from the sales of elobixibat in Japan, as a result of its ongoing involvement in the cash flows related to these royalties, the Company will continue to account for these royalties as revenue. The Company recorded the $44.5 million as a liability related to sale of future royalties (royalty obligation). The royalty obligation will be amortized using the effective interest rate method, based on the Company’s best estimate of the time it will take to reach the capped amount. The following table shows the activity within the liability account for the period ended March 31, 2019: March 31, 2019 (in thousands) Liability related to sale of future royalties—beginning balance $ 50,546 Foreign currency translation (gain)/loss in other comprehensive income/(loss) 16 Accretion of interest expense on liability related to royalty monetization Repayment of the liability (564) Liability related to sale of future royalties—ending balance $ 52,003 Less current portion classified within other current liabilities (570) Net ending liability related to sale of future royalties $ 51,433 The Company records estimated royalties due for the current period in accrued other until the payment is received from EA Pharma at which time the Company then remits payment to HCR. As royalties are remitted to HCR, the balance of the royalty obligation will be effectively repaid over the life of the RIAA. In order to determine the amortization of the royalty obligation, the Company is required to estimate the total amount of future royalty payments to be received and submitted to HCR, as noted above, based on the Company’s best estimate of the time it will take to reach the cap amount and when milestones will be received. The sum of these amounts less the $44.5 million proceeds the Company received will be recorded as interest expense over the life of the royalty obligation. Since inception, the Company’s estimate of its total interest expense resulted in a quarterly effective interest rate of approximately 4.02% The Company periodically assesses the estimated royalty payments to HCR and to the extent such payments are greater or less than its initial estimates or the timing of such payments is materially different than its original estimates, the Company will prospectively adjust the accretion of interest on the royalty obligation. There are a number of factors that could materially affect the amount and the timing of royalty payments, most of which are not within the Company’s control. Such factors include, but are not limited to, the rate of elobixibat prescriptions, the number of doses administered, the introduction of competing products, manufacturing or other delays, patent protection, adverse events that result in governmental health authority imposed restrictions on the use of the drug products, significant changes in foreign exchange rates as the royalties remitted to HCR are in U.S. dollars while sales of elobixibat are in Japanese yen, and sales never achieving forecasted numbers, which would result in reduced royalty payments and reduced non-cash interest expense over the life of the royalty obligation. To the extent future royalties result in an amount less than the liability, the Company is not obligated to fund any such shortfall.
Loss Contingencies	Loss contingencies Loss contingencies are recorded as liabilities when it is probable that a liability has occurred and the amount of loss is reasonably estimable. Disclosure is required when there is a reasonable possibility that an ultimate loss will be material. Contingent liabilities are often resolved over long periods of time. Estimating probable losses requires analysis that often depends on judgments about potential actions by third parties, such as regulators.
Recently adopted accounting pronouncements	Recently adopted accounting pronouncements As of January 1, 2019, the Company adopted ASU 2016‑02, “ Leases (Topic 842) .” The new standard establishes a right-of-use (ROU) model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. The Company has applied the transition provisions at the beginning of the period of adoption, which results in recording the cumulative adjustment to the opening balance sheet as of January 1, 2019. Under this transition provision, the Company will continue to apply the legacy guidance under ASC 840, Leases , including its disclosure requirements, in the comparative periods presented in fiscal 2019. On the date of the adoption, the Company recorded an ROU of $1.2 million and lease liabilities of $1.2 million. Additionally, the Company elected the following practical expedients: the Company has elected to not separate lease components from non-lease components in its lease contract; the Company will not apply the recognition requirements of ASC 842 to its leases with lease terms of 12 months or less but rather recognize the lease expense on a straight-line basis over the lease term; Relief package – the Company has not reassessed whether expired or existing contracts may contain a lease, the lease classification of expired or existing leases and whether previously capitalized indirect costs would qualify for capitalization under ASC 842. Use of hindsight – the Company has elected to use hindsight in assessing the likelihood of renewals, terminations and purchase options and in assessing impairment of ROU assets . Portfolio approach – the Company has elected to not apply the portfolio approach for groups of leases with similar characteristics.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies and Basis of Presentation (Tables)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Schedule of Activity within Liability Account from Inception of Royalty Transaction	March 31, 2019 (in thousands) Liability related to sale of future royalties—beginning balance $ 50,546 Foreign currency translation (gain)/loss in other comprehensive income/(loss) 16 Accretion of interest expense on liability related to royalty monetization Repayment of the liability (564) Liability related to sale of future royalties—ending balance $ 52,003 Less current portion classified within other current liabilities (570) Net ending liability related to sale of future royalties $ 51,433

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Summary of Computation of Basic EPS and Diluted EPS	Three Months Ended March 31, 2019 2018 Basic and Diluted EPS: Numerator Net loss $ (16,657) $ (1,619) Denominator Weighted average number of shares outstanding 12,001,125 10,896,575 Basic and Diluted EPS $ (1.39) $ (0.15)
Summary of Outstanding Shares Excluded from Computation of Diluted EPS	For the Three Months Ended March 31, 2019 2018 Options to purchase common stock and RSUs 1,757,728 703,016

Stock-based Compensation (Table

Stock-based Compensation (Tables)	3 Months Ended
	Mar. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of outstanding stock options	Stock Options Outstanding Weighted- Weighted- Average Average Remaining Aggregate Exercise Contractual Intrinsic Number of Price Per Term Value (in Shares Share (Years) thousands) Outstanding—December 31, 2018 1,369,504 $ 22.34 8.06 $ 8,421 Granted 413,461 $ 24.46 Expirations/forfeitures (13,329) $ 55.64 Exercises (68,908) $ 18.73 Outstanding—March 31, 2019 1,700,728 $ 22.74 8.32 $ 17,066 Exercisable—March 31, 2019 536,836 $ 14.87 6.49 $ 10,225
Schedule of fair value assumptions of share option awards	Three Months Ended March 31, 2019 Price per share of common stock $ 22.22 - 28.76 Expected term (in years) 5.6 - 5.6 Risk-free interest rate 2.2 - 2.6 Expected volatility 87.6 - 88.1 Dividend rate 0%
Summary of outstanding RSUs	Shares Weighted Non-vested and outstanding balance at December 31, 2018 $ Changes during the period: RSUs granted Non-vested and outstanding RSU balance at March 31, 2019 $

Summary of Significant Accoun_4

Summary of Significant Accounting Policies and Basis of Presentation (Details) € in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 30, 2016USD ($)	Mar. 31, 2019USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2012EUR (€)	Mar. 31, 2019EUR (€)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Disaggregation of revenue
Revenue		$ 570,000	$ 11,202,000
EA Pharma
Disaggregation of revenue
Deferred revenue							$ 0
Contract asset							$ 0
EA Pharma | License Agreement
Disaggregation of revenue
Period of written notice required prior to termination of agreement at will		180 days
EA Pharma | License Agreement | Milestone Consideration Under Agreement
Disaggregation of revenue
Milestone payment receivable					€ 4.3	$ 4,800,000
Revenue			$ 11,200,000
EA Pharma | Original license agreement | Upfront Consideration Under Agreement
Disaggregation of revenue
Upfront payment received | €				€ 10
EA Pharma | License agreement amendment | Upfront Consideration Under Agreement
Disaggregation of revenue
Upfront payment received	$ 8,000,000

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Monetization of future royalties (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		16 Months Ended
	Dec. 31, 2017	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Summary Of Significant Accounting Policies
Royalty monetization agreement			$ 44,525
Monetization Of Future Royalties [Abstract]
Accretion of interest expense on liability related to royalty monetization		$ 2,005	1,007
Liability related to sale of future royalties		51,433			$ 49,969
Quarterly effective interest rate (as a percent)				4.02%
Royalty Interest Acquisition Agreement
Summary Of Significant Accounting Policies
Maximum royalties under monetization agreement	$ 78,800
Monetization Of Future Royalties [Abstract]
Liability related to the sale of future royalties - beginning balance	50,546		44,500	$ 50,546
Foreign currency translation (gain)/loss in other comprehensive income/(loss)				16
Accretion of interest expense on liability related to royalty monetization				2,005
Repayment of the liability				(564)
Liability related to sale of future royalties - ending balance	$ 50,546	52,003	$ 44,500	$ 50,546		$ 44,500
Less current portion classified within other current liabilities		(570)
Liability related to sale of future royalties		$ 51,433
Royalty Interest Acquisition Agreement | Milestone Consideration Under Agreement
Summary Of Significant Accounting Policies
Milestone payment receivable						$ 15,000

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Recent accounting pronouncements (Details) - USD ($) $ in Millions	Jan. 01, 2019	Mar. 31, 2019
Recently adopted accounting pronouncements
Right of use asset		$ 0.4
Lease, Practical Expedients, Package [true false]	true
Lease, Practical Expedient, Use of Hindsight [true false]	true
ASU 2016-02
Recently adopted accounting pronouncements
Right of use asset	$ 1.2
Operating lease liability	$ 1.2

Commitments and Contingencies -

Commitments and Contingencies - Lease adoption (Details)	3 Months Ended
	Mar. 31, 2019USD ($)$ / ft²	Mar. 31, 2018USD ($)
Commercial real estate leases
Right of use asset	$ 400,000
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other Assets Noncurrent
Operating lease liability, current	$ 174,000
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other Liabilities Current
Operating lease liability, noncurrent	$ 213,000
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Liabilities Other Than Longterm Debt Noncurrent
Lease, Cost [Abstract]
Operating lease cost	$ 103,000
Short-term Lease, Cost	0
Variable Lease, Cost	$ 0
Weighted average remaining lease term for operating leases	2 years 7 months 6 days
Rent expense prior to adoption of Topic 842		$ 102,000
Boston MA Corporate Headquarters [Member]
Commercial real estate leases
Existence of option to extend operating lease term	true
Boston MA Corporate Headquarters, Amendment [Member]
Commercial real estate leases
Lease renewal term	88 months
Annual rent escalation (in dollars per square foot) | $ / ft²	1
Aggregated payments over the term of the lease	$ 7,300,000
Approximate annual lease payment	$ 900,000
Goteborg Sweden Administrative And Research Lab [Member]
Commercial real estate leases
Lease renewal term	3 years
Non-renewal notification period	9 months
Termination notification period	6 months
Lessee, Operating Lease, Existence of Option to Terminate [true false]	true
Quarterly payments due	$ 35,419

Commitments and Contingencies_2

Commitments and Contingencies - Agreements with CROs (Details) $ in Millions	Mar. 31, 2019USD ($)
Commitments And Contingencies Disclosure [Abstract]
Maximum future payable under agreements with CROs	$ 23.1

Commitments and Contingencies_3

Commitments and Contingencies - Legal contingency (Details) - Ferring International Center S.A. breach complaint € in Millions	Feb. 19, 2019EUR (€)item
Gain Contingencies [Line Items]
Number of clinical trials | item	2
Contingent fee as percent of net recovery	33.33%
Minimum
Gain Contingencies [Line Items]
Compensatory damages sought from respondent | €	€ 37

Net Loss Per Share - Basic EPS

Net Loss Per Share - Basic EPS and Diluted EPS (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Basic and Diluted EPS:
Net loss	$ (16,657)	$ (1,619)
Denominator
Weighted average number of shares outstanding	12,001,125	10,896,575
Basic and Diluted EPS	$ (1.39)	$ (0.15)

Net Loss Per Share - Anti-dilut

Net Loss Per Share - Anti-dilutive Shares Excluded from Computation of Diluted EPS (Details) - shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Options to purchase common stock and RSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted net loss per share	1,757,728	703,016

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income tax provision (benefit)	$ 0	$ 0

Financings (Details)

Financings (Details) - USD ($) $ / shares in Units, $ in Millions	Jan. 09, 2018	Feb. 28, 2018	Mar. 06, 2019	Oct. 31, 2017
2017 Sales Agreement
Financing
Aggregate offering price				$ 50
Issuance of common stock (in shares)		728,862
Proceeds from sale of stock		$ 24.2
2019 Sales Agreement
Financing
Aggregate offering price			$ 50
2018 Underwritten Public Offering
Financing
Issuance of common stock (in shares)	2,265,500
Price per share of common stock sold	$ 33
Proceeds from sale of stock	$ 69.9

Stock-based Compensation (Detai

Stock-based Compensation (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-based compensation expense	$ 1.8	$ 1.2

Stock-based Compensation - Summ

Stock-based Compensation - Summary of Outstanding Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Number of Shares
Beginning balance	1,369,504
Granted	413,461
Expirations/forfeitures	(13,329)
Exercises	(68,908)
Ending balance	1,700,728	1,369,504
Weighted-Average Exercise Price Per Share
Beginning balance	$ 22.34
Granted	24.46
Expirations/forfeitures	55.64
Exercises	18.73
Ending balance	$ 22.74	$ 22.34
Exercisable options
Options, exercisable	536,836
Weighted- Average Exercise Price Per Share Exercisable	$ 14.87
Options Outstanding, Weighted Average Remaining Contractual Term (Years)	8 years 3 months 26 days
Options Exercisable , Weighted- Average Remaining Contractual Term (Years)	6 years 5 months 27 days
Exercisable options, Aggregate Intrinsic Value	$ 10,225
Aggregate Intrinsic Value
Outstanding options, Aggregate Intrinsic Value Beginning	8,421
Outstanding options, Aggregate Intrinsic Value Ending	$ 17,066	$ 8,421
Vested and Expected to Vest
Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1	6 years 5 months 27 days
Weighted- Average Remaining Contractual Term (Years)		8 years 22 days

Stock-based Compensation - Addi

Stock-based Compensation - Additional information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options, exercisable	536,836
Total unrecognized compensation expense related to unvested options | $	$ 19.7
Weighted average vesting period for unvested options	2 years 9 months 18 days
Performance Based Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options, exercisable	19,422
Options, non vested	19,422

Stock-based Compensation - Fair

Stock-based Compensation - Fair value assumptions of stock option awards (Details)	3 Months Ended
	Mar. 31, 2019$ / shares
Fair value assumptions
Dividend rate	0.00%
Employee Stock Option
Fair value assumptions
Dividend rate	0.00%
Employee Stock Option | Minimum
Fair value assumptions
Price per share of common stock	$ 22.22
Expected term (in years)	5 years 7 months 6 days
Risk-free interest rate	2.20%
Expected volatility	87.60%
Employee Stock Option | Maximum
Fair value assumptions
Price per share of common stock	$ 28.76
Expected term (in years)	5 years 7 months 6 days
Risk-free interest rate	2.60%
Expected volatility	88.10%

Stock-based Compensation - Rest

Stock-based Compensation - Restricted Stock Units (Details)	3 Months Ended
	Mar. 31, 2019$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of share of common stock represented by each RSU	1
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage on first anniversary	25.00%
Shares
Non-vested and outstanding balance, beginning of period	5,000
RSUs granted	52,000
Non-vested and outstanding balance, end of period	57,000
Weighted Average Grant-Date Fair Value
Non-vested and outstanding balance, beginning of period | $ / shares	$ 27.98
RSUs granted | $ / shares	26.31
Non-vested and outstanding balance, end of period | $ / shares	$ 26.46

Stock-based Compensation - Empl

Stock-based Compensation - Employee Stock Purchase Plan (Details) shares in Millions	Jun. 30, 2018shares
2018 Employee Stock Purchase Plan
Employee Stock Purchase Plan
Shares available to be issued under the ESPP	0.3