Albireo Pharma (ALBO) 10-Q 6 Nov 19 2019 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2019	Oct. 30, 2019
Document And Entity Information [Abstract]
Document Type	10-Q
Document Period End Date	Sep. 30, 2019
Entity Registrant Name	Albireo Pharma, Inc.
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		12,686,576
Entity Central Index Key	0001322505
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 142,666	$ 163,885
Prepaid expenses and other current assets	5,353	3,765
Total current assets	148,019	167,650
Property and equipment, net	633	187
Goodwill	17,260	17,260
Other assets	5,578	369
Total assets	171,490	185,466
Current liabilities:
Accounts payable	3,185	4,352
Accrued expenses	8,459	8,165
Other current liabilities	683	308
Total current liabilities	12,327	12,825
Liability related to sale of future royalties	53,073	49,969
Other long-term liabilities	4,418	35
Total liabilities	69,818	62,829
Stockholders' Equity:
Common stock, $0.01 par value per share ? 30,000,000 authorized at September 30, 2019 and December 31, 2018; 12,685,326 and 11,969,928 issued and outstanding at September 30, 2019 and December 31, 2018	126	120
Additional paid in capital	242,638	214,694
Accumulated other comprehensive income	10,573	4,293
Accumulated deficit	(151,665)	(96,470)
Total stockholders' equity	101,672	122,637
Total liabilities and stockholders' equity	$ 171,490	$ 185,466

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 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	12,685,326	11,969,928
Common stock, shares outstanding	12,685,326	11,969,928

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Revenue	$ 1,385	$ 237	$ 3,205	$ 12,169
Operating expenses:
Research and development	11,996	9,666	31,359	22,228
General and administrative	6,010	3,850	16,788	12,216
Other operating expense (income), net	4,015	(614)	6,319	1,377
Total operating expenses	22,021	12,902	54,466	35,821
Operating loss	(20,636)	(12,665)	(51,261)	(23,652)
Interest income (expense), net	(1,274)	(1,367)	(3,934)	(4,049)
Non-operating income (expense), net		7		(2,546)
Net loss	$ (21,910)	$ (14,025)	$ (55,195)	$ (30,247)
Net loss per common share - basic and diluted	$ (1.73)	$ (1.17)	$ (4.47)	$ (2.60)
Weighted-average common shares used to compute basic and diluted net loss per common share	12,685,000	11,969,791	12,349,870	11,612,760

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (21,910)	$ (14,025)	$ (55,195)	$ (30,247)
Other comprehensive income (loss):
Foreign currency translation adjustment	3,991	(618)	6,280	3,149
Total other comprehensive income (loss)	3,991	(618)	6,280	3,149
Total comprehensive loss	$ (17,919)	$ (14,643)	$ (48,915)	$ (27,098)

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - 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	$ 114,521	$ 1,001	$ (50,359)	$ 65,252
Balance (in shares) at Dec. 31, 2017	8,902,784
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense		1,189			1,189
Issuance of common stock, net of costs	$ 30	94,120			94,150
Issuance of common stock (in shares)	2,994,362
Other comprehensive income (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, 2017	$ 89	114,521	1,001	(50,359)	65,252
Balance (in shares) at Dec. 31, 2017	8,902,784
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)					3,149
Net loss					(30,247)
Balance at end of period at Sep. 30, 2018	$ 120	213,005	4,150	(80,608)	136,667
Balance (in shares) at Sep. 30, 2018	11,969,928
Balance at beginning 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
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense		1,056			1,056
Exercise of options	$ 1	254			255
Exercise of options (in shares)	60,345
Other comprehensive income (loss)			2,573		2,573
Net loss				(14,605)	(14,605)
Balance at end of period at Jun. 30, 2018	$ 120	211,140	4,768	(66,583)	149,445
Balance (in shares) at Jun. 30, 2018	11,957,491
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense		1,623			1,623
Exercise of options		252			252
Exercise of options (in shares)	12,437
Issuance of common stock, net of costs		(10)			(10)
Other comprehensive income (loss)			(618)		(618)
Net loss				(14,025)	(14,025)
Balance at end of period at Sep. 30, 2018	$ 120	213,005	4,150	(80,608)	136,667
Balance (in shares) at Sep. 30, 2018	11,969,928
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]
Stock-based compensation expense		1,823			1,823
Exercise of options		1,290			1,290
Exercise of options (in shares)	68,908
Other comprehensive income (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
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]
Other comprehensive income (loss)					6,280
Net loss					(55,195)
Balance at end of period at Sep. 30, 2019	$ 126	242,638	10,573	(151,665)	101,672
Balance (in shares) at Sep. 30, 2019	12,685,326
Balance at beginning 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
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense		2,049			2,049
Exercise of awards		110			110
Exercise of awards (in shares)	9,123
Issuance of common stock, net of costs	$ 6	20,768			20,774
Issuance of common stock (in shares)	637,367
Other comprehensive income (loss)			(9)		(9)
Net loss				(16,628)	(16,628)
Balance at end of period at Jun. 30, 2019	$ 126	240,734	6,582	(129,755)	117,687
Balance (in shares) at Jun. 30, 2019	12,685,326
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense		1,826			1,826
Exercise of awards		78			78
Other comprehensive income (loss)			3,991		3,991
Net loss				(21,910)	(21,910)
Balance at end of period at Sep. 30, 2019	$ 126	$ 242,638	$ 10,573	$ (151,665)	$ 101,672
Balance (in shares) at Sep. 30, 2019	12,685,326

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities:
Net loss	$ (55,195)	$ (30,247)
Adjustments to reconcile net loss to net cash used in operating activities:
Non cash interest expense on liability related to royalty monetization	6,179	4,880
Depreciation and amortization	89	33
Change in fair value of financial instruments		(1)
Gain on sale of property, plant and equipment		(14)
Stock-based compensation expense	5,698	3,868
Foreign currency adjustments	8,317	4,802
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(1,861)	(1,122)
Other assets	(238)	379
Accounts payable	(935)	2,292
Accrued expenses	(2,397)	(1,516)
Other current and long-term liabilities	(176)	(160)
Net cash used in operating activities	(40,519)	(16,806)
Cash flows from investing activities:
Purchase of property, plant and equipment	(523)	(61)
Proceeds from sale of property, plant and equipment		14
Net cash used in investing activities	(523)	(47)
Cash flows from financing activities:
Proceeds from issuance of common stock, net of issuance costs	20,774	94,139
Royalty monetization		44,525
Proceeds from exercise of options	1,478	507
Net cash provided by financing activities	22,252	139,171
Effect of exchange rate changes on cash and cash equivalents	(2,429)	(1,947)
Net (decrease) increase in cash and cash equivalents	(21,219)	120,371
Cash and cash equivalents - beginning of period	163,885	53,231
Cash and cash equivalents - end of period	142,666	$ 173,602
Supplemental disclosures of cash and non-cash activities:
Purchase of property, plant and equipment in accounts payable	17
Right of use assets obtained in exchange for operating lease obligation	$ 4,665

Summary of Significant Accounti

Summary of Significant Accounting Policies and Basis of Presentation	9 Months Ended
	Sep. 30, 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 as a once per-day treatment given orally in a capsule or sprinkled over food, initially being evaluated using the planned commercial formulation in patients with progressive familial intrahepatic cholestasis (PFIC) types 1 and 2. PFIC is 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. The Company combined prepaid expenses and other assets with other receivables and reflected this in the Condensed Consolidated Balance Sheets. The Company combined prepaid expenses and other assets with other receivables and trade receivables in the Condensed Consolidated Statements of Cash Flows. These combinations are reflected at September 30, 2019 and December 31, 2018, and for the nine months ended September 30, 2019 and 2018, respectively, with a change in the prior period presentation being made to conform to the current period presentation. There was no change to previously reported net loss or total comprehensive loss in the prior period presented as a result. In the opinion of management, all adjustments (including normal recurring adjustments) considered necessary for fair presentation have been included in the Condensed Consolidated Financial Statements. The results of operations for the nine months ended September 30, 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 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 period-end exchange rates of monetary assets and liabilities denominated in foreign currencies are recognized within other operating 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 September 30, 2019 and December 31, 2018; b. income and expenses for each statement of comprehensive 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, and the accretion of interest on the monetization liability. Actual results could materially differ from these estimates. Revenue recognition 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 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 September 30, 2019, the Company is eligible to receive a regulatory-based milestone payment under the Agreement of €4.3 million ($4.7 million based on the Euro to USD exchange rate as of September 30, 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. 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 September 30, 2019: September 30, 2019 (in thousands) Liability related to sale of future royalties—beginning balance $ 50,546 Foreign currency translation gain 73 Accretion of interest expense on liability related to royalty monetization Repayment of the liability (2,343) Liability related to sale of future royalties—ending balance $ 54,455 Less current portion classified within accrued expenses (1,382) Net ending liability related to sale of future royalties $ 53,073 The Company records estimated royalties due for the current period in accrued other expenses 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 4.03%. 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. 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 a ROU asset 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	9 Months Ended
	Sep. 30, 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	9 Months Ended
	Sep. 30, 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 space in Göteborg, Sweden, both of which are accounted for as operating leases. These leases include renewal rights and, 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 prior office space with a new office space that is being leased from the same landlord and (ii) extend the term of the lease through the date ending eighty-eight months following July 1, 2019, when the Company took control of the new leased space. The new leased space contains monthly lease payments subject to annual escalations of $1.00 per square foot for the remaining term of the lease with the Company obligated to make approximately $6.6 million of aggregate lease payments over the term of the lease, or approximately $900,000 annually. The Company’s lease in Göteborg, Sweden includes the rental of office 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 February 2022, with quarterly payments of $32,000. As of September 30, 2019, the net balance of ROU assets totaled $4.8 million and were classified within other non-current assets. The current and long-term balances of lease liabilities at September 30, 2019 were $0.5 million and $4.3 million, respectively, and were classified within other liabilities, and long-term liabilities, respectively. Operating lease expense under ASC 842 was $0.3 million and $0.4 million, respectively, for the three months and nine months ended September 30, 2019. There were no short-term lease or variable lease costs incurred for the three months and nine months ended September 30, 2019. As of September 30, 2019, the weighted average remaining lease term for the Company’s operating leases was 6.87 years. As of September 30, 2019, the weighted- average discount rate was 9.95%. Rent expense recognized under legacy GAAP for the Company’s operating leases was $0.1 million and $0.3 million for the three and nine months ended September 30, 2018, respectively. The following table summarizes the Company’s significant contractual obligations under operating leases as of payment due date by period at September 30, 2019: Total Minimum Lease Payments (in thousands) 2019 (Remainder of year) $ 224 2020 1,003 2021 1,007 2022 906 2023 921 2024 and beyond 2,690 Total minimum lease payments $ 6,751 Less imputed interest (1,910) Total lease liability $ 4,841 Reported as: Other current liabilities $ 514 Other long-term liabilities 4,327 Total lease liabilities $ 4,841 Agreements with CROs As of September 30, 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 $20.3 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 (converted to $40.5 million as of September 30, 2019). On July 31, 2019 Respondent filed a motion to dismiss the complaint. The Company filed an answer to Respondent’s motion on September 30, 2019. 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	9 Months Ended
	Sep. 30, 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 September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Basic and Diluted EPS: Numerator Net loss $ (21,910) $ (14,025) $ (55,195) $ (30,247) Denominator Weighted average number of shares outstanding 12,685,000 11,969,791 12,349,870 11,612,760 Basic and Diluted EPS $ (1.73) $ (1.17) $ (4.47) $ (2.60) The following outstanding common stock equivalents were excluded from the computation of Diluted EPS for the three and nine months ended September 30, 2019 and 2018 because including them would have been anti-dilutive: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2019 2018 2019 2018 Options to purchase common stock and RSUs 1,759,963 1,442,361 1,759,963 1,442,361

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 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 September 30, 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	9 Months Ended
	Sep. 30, 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, the Company terminated the 2017 Sales Agreement and 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. In May 2019, the Company sold an aggregate of 637,367 shares of common stock pursuant to the 2019 Sales Agreement and received proceeds, net of offering expenses, of approximately $20.8 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	9 Months Ended
	Sep. 30, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-based Compensation	7. Stock-based Compensation The Company granted 496,361 options at a weighted average price of $25.64 and 52,000 RSUs with a weighted average grant date fair value of $26.31 during the nine months ended September 30, 2019. The Company recorded the following stock-based compensation expense: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (in thousands) (in thousands) Employee awards: Research and development expense $ 742 $ 549 $ 2,242 $ 1,260 General and administrative expense 1,084 1,074 3,456 2,608 Total stock-based compensation expense $ 1,826 $ 1,623 $ 5,698 $ 3,868

Summary of Significant Accoun_2

Summary of Significant Accounting Policies and Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 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. The Company combined prepaid expenses and other assets with other receivables and reflected this in the Condensed Consolidated Balance Sheets. The Company combined prepaid expenses and other assets with other receivables and trade receivables in the Condensed Consolidated Statements of Cash Flows. These combinations are reflected at September 30, 2019 and December 31, 2018, and for the nine months ended September 30, 2019 and 2018, respectively, with a change in the prior period presentation being made to conform to the current period presentation. There was no change to previously reported net loss or total comprehensive loss in the prior period presented as a result. In the opinion of management, all adjustments (including normal recurring adjustments) considered necessary for fair presentation have been included in the Condensed Consolidated Financial Statements. The results of operations for the nine months ended September 30, 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 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 period-end exchange rates of monetary assets and liabilities denominated in foreign currencies are recognized within other operating 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 September 30, 2019 and December 31, 2018; b. income and expenses for each statement of comprehensive 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, and the accretion of interest on the monetization liability. Actual results could materially differ from these estimates.
Revenue recognition	Revenue recognition 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 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 September 30, 2019, the Company is eligible to receive a regulatory-based milestone payment under the Agreement of €4.3 million ($4.7 million based on the Euro to USD exchange rate as of September 30, 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. 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 September 30, 2019: September 30, 2019 (in thousands) Liability related to sale of future royalties—beginning balance $ 50,546 Foreign currency translation gain 73 Accretion of interest expense on liability related to royalty monetization Repayment of the liability (2,343) Liability related to sale of future royalties—ending balance $ 54,455 Less current portion classified within accrued expenses (1,382) Net ending liability related to sale of future royalties $ 53,073 The Company records estimated royalties due for the current period in accrued other expenses 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 4.03%. 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.
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 a ROU asset 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)	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Schedule of Activity within Liability Account from Inception of Royalty Transaction	September 30, 2019 (in thousands) Liability related to sale of future royalties—beginning balance $ 50,546 Foreign currency translation gain 73 Accretion of interest expense on liability related to royalty monetization Repayment of the liability (2,343) Liability related to sale of future royalties—ending balance $ 54,455 Less current portion classified within accrued expenses (1,382) Net ending liability related to sale of future royalties $ 53,073

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2019
Commitments And Contingencies Disclosure [Abstract]
Schedule of contractual obligations under operating leases by period	The following table summarizes the Company’s significant contractual obligations under operating leases as of payment due date by period at September 30, 2019: Total Minimum Lease Payments (in thousands) 2019 (Remainder of year) $ 224 2020 1,003 2021 1,007 2022 906 2023 921 2024 and beyond 2,690 Total minimum lease payments $ 6,751 Less imputed interest (1,910) Total lease liability $ 4,841 Reported as: Other current liabilities $ 514 Other long-term liabilities 4,327 Total lease liabilities $ 4,841

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Summary of Computation of Basic EPS and Diluted EPS	Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Basic and Diluted EPS: Numerator Net loss $ (21,910) $ (14,025) $ (55,195) $ (30,247) Denominator Weighted average number of shares outstanding 12,685,000 11,969,791 12,349,870 11,612,760 Basic and Diluted EPS $ (1.73) $ (1.17) $ (4.47) $ (2.60)
Summary of Outstanding Shares Excluded from Computation of Diluted EPS	For the Three Months Ended September 30, For the Nine Months Ended September 30, 2019 2018 2019 2018 Options to purchase common stock and RSUs 1,759,963 1,442,361 1,759,963 1,442,361

Stock-based Compensation (Table

Stock-based Compensation (Tables)	9 Months Ended
	Sep. 30, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of stock-based compensation expense	Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (in thousands) (in thousands) Employee awards: Research and development expense $ 742 $ 549 $ 2,242 $ 1,260 General and administrative expense 1,084 1,074 3,456 2,608 Total stock-based compensation expense $ 1,826 $ 1,623 $ 5,698 $ 3,868

Summary of Significant Accoun_4

Summary of Significant Accounting Policies and Basis of Presentation - Royalties (Details) € in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Jan. 31, 2018USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2019EUR (€)	Sep. 30, 2019USD ($)	Dec. 31, 2018USD ($)
Disaggregation of revenue
Revenue		$ 1,385,000	$ 237,000	$ 3,205,000	$ 12,169,000
EA Pharma
Disaggregation of revenue
Deferred revenue								$ 0
Contract asset								$ 0
EA Pharma | License Agreement | Milestone Consideration Under Agreement
Disaggregation of revenue
Milestone payment receivable						€ 4.3	$ 4,700,000
Revenue	$ 11,200,000

Summary of Significant Accoun_5

Summary of Significant Accounting Policies and Basis of Presentation - Monetization of future royalties (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended		22 Months Ended
	Dec. 31, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Dec. 31, 2018
Summary Of Significant Accounting Policies
Royalty monetization			$ 44,525
Monetization Of Future Royalties [Abstract]
Accretion of interest expense on liability related to royalty monetization		$ 6,179	4,880
Liability related to sale of future royalties				$ 53,073	$ 49,969
Quarterly effective interest rate (as a percent)				4.03%
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
Foreign currency translation (gain)/loss in other comprehensive income/(loss)		73
Accretion of interest expense on liability related to royalty monetization		6,179
Repayment of the liability		(2,343)
Liability related to sale of future royalties - ending balance		$ 50,546		$ 54,455	$ 50,546
Less current portion classified within other current liabilities				(1,382)
Liability related to sale of future royalties				$ 53,073
HCR | Royalty Interest Acquisition Agreement
Summary Of Significant Accounting Policies
Royalty monetization	44,500
Milestone payment receivable	15,000
Monetization Of Future Royalties [Abstract]
Liability related to the sale of future royalties - beginning balance			44,500
Liability related to sale of future royalties - ending balance	$ 44,500		$ 44,500

Summary of Significant Accoun_6

Summary of Significant Accounting Policies and Basis of Presentation - Recent accounting pronouncements (Details) - USD ($) $ in Thousands	Jan. 01, 2019	Sep. 30, 2019
Recently adopted accounting pronouncements
Right of use asset		$ 4,800
Total lease liability		$ 4,841
Lease, Practical Expedients, Package [true false]	true
Lease, Practical Expedient, Use of Hindsight [true false]	true
ASU 2016-02
Recently adopted accounting pronouncements
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]	true
Right of use asset	$ 1,200
Total lease liability	$ 1,200

Commitments and Contingencies -

Commitments and Contingencies - Lease adoption (Details)	Jul. 01, 2019USD ($)$ / ft²	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)
Commercial real estate leases
Aggregated payments over the term of the lease		$ 6,751,000		$ 6,751,000
Right of use asset		$ 4,800,000		$ 4,800,000
Operating Lease, Right-of-Use Asset, Statement of Financial Position		us-gaap:OtherAssetsNoncurrent		us-gaap:OtherAssetsNoncurrent
Operating lease liability, current		$ 514,000		$ 514,000
Operating Lease, Liability, Current, Statement of Financial Position		us-gaap:OtherLiabilitiesCurrent		us-gaap:OtherLiabilitiesCurrent
Operating lease liability, noncurrent		$ 4,327,000		$ 4,327,000
Operating Lease, Liability, Noncurrent, Statement of Financial Position		us-gaap:OtherLiabilitiesNoncurrent		us-gaap:OtherLiabilitiesNoncurrent
Lease, Cost [Abstract]
Operating lease expense		$ 300,000		$ 400,000
Short term lease costs		0		0
Variable Lease, Cost		$ 0		$ 0
Weighted average remaining lease term for operating leases		6 years 10 months 13 days		6 years 10 months 13 days
Weighted average discount rate (as a percent)		9.95%		9.95%
Rent expense prior to adoption of Topic 842			$ 100,000		$ 300,000
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	$ 6,600,000
Approximate annual lease payment	$ 900,000
Goteborg Sweden Administrative And Research Lab [Member]
Commercial real estate leases
Lease renewal term		3 years		3 years
Non-renewal notification period				9 months
Termination notification period				6 months
Lessee, Operating Lease, Existence of Option to Terminate				true
Quarterly payments due				$ 32,000

Commitments and Contingencies_2

Commitments and Contingencies - Lease maturity (Details) $ in Thousands	Sep. 30, 2019USD ($)
Operating lease payments due
2019 (Remainder of year)	$ 224
2020	1,003
2021	1,007
2022	906
2023	921
2024 and beyond	2,690
Total minimum lease payments	6,751
Less imputed interest	(1,910)
Total lease liability	4,841
Operating lease liability, current	$ 514
Operating Lease, Liability, Current, Statement of Financial Position	us-gaap:OtherLiabilitiesCurrent
Operating lease liability, noncurrent	$ 4,327
Operating Lease, Liability, Noncurrent, Statement of Financial Position	us-gaap:OtherLiabilitiesNoncurrent
Total lease liabilities	$ 4,841

Commitments and Contingencies_3

Commitments and Contingencies - Agreements with CROs (Details) $ in Millions	Sep. 30, 2019USD ($)
Commitments And Contingencies Disclosure [Abstract]
Maximum future payable under agreements with CROs	$ 20.3

Commitments and Contingencies_4

Commitments and Contingencies - Legal contingency (Details) - Ferring International Center S.A. breach complaint $ in Thousands, € in Millions	Feb. 19, 2019EUR (€)item	Sep. 30, 2019USD ($)
Gain Contingencies [Line Items]
Number of clinical trials	2
Compensatory damages sought from respondent	€ 37	$ 40,500
Contingent fee as percent of net recovery	33.33%

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						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Basic and Diluted EPS:
Net loss	$ (21,910)	$ (16,628)	$ (16,657)	$ (14,025)	$ (14,605)	$ (1,619)	$ (55,195)	$ (30,247)
Denominator
Weighted average number of shares outstanding	12,685,000			11,969,791			12,349,870	11,612,760
Basic and Diluted EPS	$ (1.73)			$ (1.17)			$ (4.47)	$ (2.60)

Net Loss Per Share - Anti-dilut

Net Loss Per Share - Anti-dilutive Shares Excluded from Computation of Diluted EPS (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 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	1,759,963	1,442,361	1,759,963	1,442,361

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income tax provision (benefit)	$ 0	$ 0

Financings (Details)

Financings (Details) - USD ($) $ / shares in Units, $ in Millions	Jan. 09, 2018	May 31, 2019	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
Issuance of common stock (in shares)		637,367
Proceeds from sale of stock		$ 20.8
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 activi

Stock-based Compensation activity (Details)	9 Months Ended
	Sep. 30, 2019$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted during period | shares	496,361
Weighted average price of options granted | $ / shares	$ 25.64
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
RSUs granted during period | shares	52,000
RSU weighted average grant date fair value | $ / shares	$ 26.31

Stock-based Compensation - Stoc

Stock-based Compensation - Stock-based compensation expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1,826	$ 1,623	$ 5,698	$ 3,868
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	742	549	2,242	1,260
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1,084	$ 1,074	$ 3,456	$ 2,608