Concert Pharmaceuticals (CNCE) 10-Q 8 Aug 17 2017 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2017	Aug. 04, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q2
Trading Symbol	CNCE
Entity Registrant Name	CONCERT PHARMACEUTICALS, INC.
Entity Central Index Key	1,367,920
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		22,687,187

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 27,591	$ 40,555
Investments, available for sale	75,829	55,630
Interest receivable	218	164
Accounts receivable	273	27
Prepaid expenses and other current assets	2,318	1,353
Total current assets	106,229	97,729
Property and equipment, net	1,944	2,199
Restricted cash	400	400
Other assets	49	67
Total assets	108,622	100,395
Current liabilities:
Accounts payable	1,000	545
Accrued expenses and other liabilities	3,909	3,853
Deferred revenue, current portion	1,168	1,172
Total current liabilities	6,077	5,570
Deferred revenue, net of current portion	8,857	8,878
Deferred lease incentive, net of current portion	84	249
Deferred rent, net of current portion	35	104
Loan payable, net of discount	29,188	0
Total liabilities	44,241	14,801
Commitments
Stockholders’ equity:
Preferred stock, $0.001 par value per share; 5,000,000 shares authorized; no shares issued and outstanding in 2017 and 2016, respectively
Common stock, $0.001 par value per share; 100,000,000 shares authorized; 22,620,822 and 22,319,516 shares issued and 22,616,067 and 22,316,982 outstanding in 2017 and 2016, respectively	23	22
Additional paid-in capital	262,644	257,461
Accumulated other comprehensive loss	(44)	(7)
Accumulated deficit	(198,242)	(171,882)
Total stockholders’ equity	64,381	85,594
Total liabilities and stockholders’ equity	$ 108,622	$ 100,395

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Jun. 30, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	22,620,822	22,319,516
Common stock, shares outstanding	22,616,067	22,316,982

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue:
License and research and development revenue	$ 15	$ 71	$ 35	$ 127
Total revenue	15	71	35	127
Operating expenses:
Research and development	7,285	9,816	15,522	20,269
General and administrative	5,707	3,828	10,960	7,405
Total operating expenses	12,992	13,644	26,482	27,674
Loss from operations	(12,977)	(13,573)	(26,447)	(27,547)
Investment income	155	132	292	226
Interest and other expense	(205)	0	(205)	0
Net loss	(13,027)	(13,441)	(26,360)	(27,321)
Other comprehensive (loss) income:
Unrealized (loss) gain on investments	(10)	12	(37)	61
Comprehensive loss	$ (13,037)	$ (13,429)	$ (26,397)	$ (27,260)
Net loss per share applicable to common stockholders - basic and diluted (in dollars per share)	$ (0.58)	$ (0.60)	$ (1.17)	$ (1.23)
Weighted-average number of common shares used in net (loss) income per share applicable to common stockholders— basic and diluted (in shares)	22,579	22,217	22,479	22,208

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Operating activities
Net loss	$ (26,360)	$ (27,321)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	493	430
Stock-based compensation expense	3,216	2,569
Accretion of premiums and discounts on investments	100	265
Amortization of discount on loan payable	42	0
Amortization of deferred lease incentive	(161)	(156)
Loss on disposal of asset	4	2
Changes in operating assets and liabilities:
Accounts receivable	(246)	(63)
Interest receivable	(54)	(30)
Prepaid expenses and other current assets	(965)	348
Other assets	18	56
Accounts payable	455	1,901
Accrued expenses and other liabilities	(8)	(1,399)
Income taxes payable	0	(75)
Deferred rent	(44)	(19)
Deferred revenue	(25)	(82)
Net cash used in operating activities	(23,535)	(23,574)
Investing activities
Purchases of property and equipment	(229)	(231)
Purchases of investments	(64,919)	(75,906)
Maturities of investments	44,583	60,613
Net cash used in investing activities	(20,565)	(15,524)
Financing activities
Proceeds from loan, net	29,680	0
Proceeds from exercise of stock options	1,456	239
Net cash provided by financing activities	31,136	239
Net decrease in cash and cash equivalents	(12,964)	(38,859)
Cash and cash equivalents at beginning of period	40,555	92,510
Cash and cash equivalents at end of period	27,591	53,651
Supplemental cash flow information:
Cash paid for income taxes	0	85
Purchases of property and equipment unpaid at period end	6	23
Issuance of stock warrants	$ 512	$ 0

Nature of Business

Nature of Business	6 Months Ended
	Jun. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	Nature of Business Concert Pharmaceuticals, Inc., or Concert or the Company, was incorporated on April 12, 2006 as a Delaware corporation with operations based in Lexington, Massachusetts. The Company is a clinical stage biopharmaceutical company that applies its extensive knowledge of deuterium chemistry to discover and develop novel small molecule drugs. The Company’s approach typically starts with approved drugs that the Company believes can be improved with deuterium substitution to provide better pharmacokinetic or metabolic properties, thereby enhancing clinical safety, tolerability or efficacy. The Company believes this approach may enable drug discovery and clinical development that is more efficient and less expensive than conventional small molecule drug research and development. The Company has a pipeline of clinical candidates as well as research efforts to identify new product candidates. On March 3, 2017, the Company entered into an Asset Purchase Agreement (the "Asset Purchase Agreement") with Vertex Pharmaceuticals, Inc., through Vertex Pharmaceuticals (Europe) Limited ("Vertex"), pursuant to which the Company agreed to sell and assign CTP-656 and other cystic fibrosis assets of the Company, for up to $250 million subject to the satisfaction of certain closing conditions. On May 24, 2017, Concert shareholders authorized the sale of CTP-656 and other assets related to the treatment of cystic fibrosis. In July 2017 the U.S. Federal Trade Commission (the "FTC") terminated the waiting period for the pending sale of CTP-656 under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (HSR Act). The expiration of the HSR Act waiting period represented the final regulatory closing condition required to complete the sale. In July 2017, the Asset Purchase Agreement closed and Vertex paid the Company $160 million in cash consideration, with $16 million to initially be held in escrow. Additional information concerning the sale of CTP-656 is discussed further in Note 6. On June 8, 2017, the Company entered into a Loan and Security Agreement, or the Loan Agreement, with Hercules Capital, Inc., or Hercules, pursuant to which Hercules agreed to make available to the Company a secured term loan facility in the amount of $30 million , or the Term Loan Facility, subject to certain terms and conditions. Additional information concerning the Loan Agreement is discussed further in Note 11. The Company had cash and cash equivalents and investments of $103.4 million at June 30, 2017. The Company believes that its cash and cash equivalents and investments at June 30, 2017, will be sufficient to allow the Company to fund its current operating plan for at least the next twelve months. The Company may pursue additional cash resources through public or private financings and by establishing collaborations with or licensing its technology to other companies and through other arrangements. Since its inception, the Company has generated an accumulated deficit of $198.2 million through June 30, 2017. The Company's operating results may fluctuate significantly from year to year, depending on the timing and magnitude of cash payments received pursuant to collaboration and licensing arrangements and other agreements and the timing and magnitude of clinical trial and other development activities under its current development programs. Substantially all the Company's net losses have resulted from costs incurred in connection with its research and development programs and from general and administrative costs associated with its operations. The Company expects to continue to incur significant expenses and increasing operating losses for at least the next several years. The Company is subject to risks common to companies in the biotechnology industry, including, but not limited to, risks of failure or unsatisfactory results of nonclinical studies and clinical trials, the need to obtain additional financing to fund the future development of its pipeline, the need to obtain marketing approval for its product candidates, the need to successfully commercialize and gain market acceptance of its product candidates, dependence on key personnel, protection of proprietary technology, compliance with government regulations, development by competitors of technological innovations and ability to transition from pilot-scale manufacturing to large-scale production of products. Unless otherwise indicated, all amounts are in thousands except share and per share amounts.

Basis of Presentation and Signi

Basis of Presentation and Significant Accounting Policies	6 Months Ended
	Jun. 30, 2017
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	Basis of Presentation and Significant Accounting Policies Basis of Presentation The accompanying condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and with 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 generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments, consisting of normal recurring accruals and revisions of estimates, considered necessary for a fair presentation of the condensed consolidated financial statements have been included. Interim results for the three and six months ended June 30, 2017 are not necessarily indicative of the results that may be expected for the fiscal year ending December 31, 2017 or any other future period. The accompanying condensed consolidated financial statements reflect the accounts of Concert and its subsidiaries. All intercompany transactions between the Company and its subsidiaries have been eliminated. Management has determined that the Company operates in one segment: the development of pharmaceutical products on its own behalf or in collaboration with others. The information included in this quarterly report on Form 10-Q should be read in conjunction with the Company’s consolidated financial statements and the accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 filed with the Securities and Exchange Commission on March 6, 2017. Use of Estimates and Summary of Significant Accounting Policies In preparing the condensed consolidated financial statements, management used estimates in the following areas, among others: revenue recognition for multiple-element revenue arrangements; stock-based compensation expense; income tax expense; accrued expenses; and the evaluation of the existence of conditions and events that raise substantial doubt regarding the Company’s ability to continue as a going concern. Actual results could differ from those estimates. There have been no material changes to the significant accounting policies previously disclosed in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2016. Recent Accounting Pronouncements In May 2014, the Financial Accounting Standard Board, or FASB, issued Accounting Standards Update, or ASU, No. 2014-09, Revenue from Contracts with Customers (Topic 606), or ASU 2014-09, which stipulates that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve this core principle, ASU 2014-09 provides that an entity should apply the following steps: (1) identify the contract(s) with a customer, (2) identify the performance obligations in the contract, (3) determine the transaction price, (4) allocate the transaction price to the performance obligations in the contract and (5) recognize revenue when (or as) the entity satisfies a performance obligation. This update will be effective for the Company beginning in the first quarter of fiscal 2018 as a result of the FASB’s one year deferral of the effective date for this standard. The amendments may be applied retrospectively to each prior period (full retrospective) or retrospectively with the cumulative effect recognized as of the date of initial application (modified retrospective). Previously, the Company disclosed that it intended to apply ASU 2014-09 using the full retrospective approach. Due to the additional adoption efforts required of issuers under the full retrospective approach, the Company now intends to adopt ASU 2014-09 in the first quarter of 2018 using the modified retrospective approach. Under the modified retrospective approach, the cumulative effect of applying the standard would be recognized at the date of initial application within retained earnings. The Company is currently evaluating the effect of adopting the requirements of ASU 2014-09 as it relates to the accounting for its collaboration arrangements with Celgene Pharmaceuticals, Inc., Jazz Pharmaceuticals plc and Avanir Pharmaceuticals, Inc., and its patent assignment agreement with Auspex Pharmaceuticals, Inc. The Company is also in the process of evaluating appropriate changes to its controls to support revenue recognition and disclosure under the new standard. In August 2014, the FASB issued ASU No. 2014-15, Disclosure of Uncertainties About an Entity’s Ability to Continue as a Going Concern, or ASU 2014-15. ASU 2014-15 amends FASB Accounting Standards Codification, or ASC, 205-40, Presentation of Financial Statements – Going Concern, by providing guidance on determining when and how reporting entities must disclose going-concern uncertainties in their financial statements, including requiring management to perform interim and annual assessments of an entity’s ability to continue as a going concern within one year of the date of issuance of the entity’s financial statements and providing certain disclosures if there is substantial doubt about the entity’s ability to continue as a going concern. The Company was required to apply the requirements of ASU 2014-15 in its interim financial statements beginning in the first quarter of fiscal 2017. With respect to the interim financial statements as of June 30, 2017, the Company did not identify any conditions or events that raise substantial doubt about its ability to continue as a going concern within one year after the date the financial statements are issued. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), or ASU 2016-02. ASU 2016-02 requires lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by all leases with terms of more than 12 months. ASU 2016-02 also will require certain qualitative and quantitative disclosures designed to give financial statement users information on the amount, timing, and uncertainty of cash flows arising from leases. ASU 2016-02 will be effective for the Company on January 1, 2019, with early adoption permitted. The Company is currently evaluating the impact ASU 2016-02 will have on its financial statements. In March 2016, the FASB issued ASU No. 2016-09, Compensation-Stock Compensation-Improvements to Employee Share-Based Payment Accounting, or ASU 2016-09. This update simplifies several aspects of the accounting for share-based compensation arrangements, including accounting for income taxes, forfeitures and statutory tax withholding requirements as well as classification of related amounts on the statement of cash flows. The Company adopted this ASU on January 1, 2017 and it did not have a material effect on the consolidated financial statements and related disclosures. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326)-Measurement of Credit Losses on Financial Instruments, or ASU 2016-13. The new standard requires entities to measure all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions and reasonable and supportable forecasts. ASU 2016-13 will become effective for the Company for fiscal years beginning after December 15, 2019, with early adoption permitted. The Company is currently evaluating the impact ASU 2016-13 will have on its financial statements and related disclosures.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company has certain financial assets and liabilities that are recorded at fair value which have been classified as Level 1, 2 or 3 within the fair value hierarchy as described in the accounting standards for fair value measurements: • Level 1—quoted prices for identical instruments in active markets; • Level 2—quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-derived valuations in which all significant inputs and significant value drivers are observable in active markets; and • Level 3—valuations derived from valuation techniques in which one or more significant value drivers are unobservable. The tables below present information about the Company’s financial assets and liabilities that are measured and carried at fair value as of June 30, 2017 and December 31, 2016 (in thousands) and indicate the level within the fair value hierarchy where each measurement is classified. Level 1 Level 2 Level 3 Total June 30, 2017 Cash equivalents: Money market funds $ 23,790 $ — $ — $ 23,790 Investments, available for sale: U.S. Treasury obligations 21,527 — — 21,527 Government agency securities 53,304 998 — 54,302 Total $ 98,621 $ 998 $ — $ 99,619 Level 1 Level 2 Level 3 Total December 31, 2016 Cash equivalents: Money market funds $ 26,257 $ — $ — $ 26,257 U.S. Treasury obligations — 1,001 — 1,001 Investments, available for sale: U.S. Treasury obligations 10,034 5,503 — 15,537 Government agency securities 24,545 15,548 — 40,093 Total $ 60,836 $ 22,052 $ — $ 82,888 The carrying amount of financial instruments not carried at fair value, such as the loan payable, approximate fair value. The carrying value of the Company’s loan payable approximates fair value because the interest rate yield for the loan approximates current market yields. The disclosed fair value of the Company’s loan payable represents a Level 3 measurement within the fair value hierarchy.

Cash, Cash Equivalents and Inve

Cash, Cash Equivalents and Investments	6 Months Ended
	Jun. 30, 2017
Cash and Cash Equivalents [Abstract]
Cash, Cash Equivalents and Investments	Cash, Cash Equivalents and Investments Cash equivalents include all highly liquid investments maturing within 90 days from the date of purchase. Investments consist of securities with original maturities greater than 90 days when purchased. The Company classifies these investments as available-for-sale and records them at fair value in the accompanying consolidated balance sheets. Unrealized gains or losses are included in accumulated other comprehensive income (loss). Premiums or discounts from par value are amortized to investment income over the life of the underlying investment. Cash, cash equivalents and investments, available for sale included the following at June 30, 2017 and December 31, 2016: Average maturity Amortized cost Unrealized gains Unrealized losses Fair value June 30, 2017 Cash $ 3,801 $ — $ — $ 3,801 Money market funds 23,790 — — 23,790 Cash and cash equivalents $ 27,591 $ — $ — $ 27,591 U.S. Treasury obligations 184 days 21,544 — (17 ) 21,527 Government agency securities 187 days 54,329 — (27 ) 54,302 Investments, available for sale $ 75,873 $ — $ (44 ) $ 75,829 Average maturity Amortized cost Unrealized gains Unrealized losses Fair value December 31, 2016 Cash $ 13,297 $ — $ — $ 13,297 Money market funds 26,257 — — 26,257 U.S. Treasury obligations 31 days 1,001 — — 1,001 Cash and cash equivalents $ 40,555 $ — $ — $ 40,555 U.S. Treasury obligations 125 days 15,534 4 (1 ) 15,537 Government agency securities 140 days 40,103 1 (11 ) 40,093 Investments, available for sale $ 55,637 $ 5 $ (12 ) $ 55,630 Although available to be sold to meet operating needs or otherwise, securities are generally held through maturity. The cost of securities sold is determined based on the specific identification method for purposes of recording realized gains and losses. During 2017 and 2016, there were no realized gains or losses on sales of investments, and no investments were adjusted for other than temporary declines in fair value.

Accrued Expenses and Other Liab

Accrued Expenses and Other Liabilities	6 Months Ended
	Jun. 30, 2017
Payables and Accruals [Abstract]
Accrued Expenses and Other Liabilities	Accrued Expenses and Other Liabilities Accrued expenses and other liabilities consisted of the following: June 30, December 31, Accrued professional fees and other $ 1,366 $ 487 Employee compensation and benefits 1,320 2,010 Research and development expenses 604 930 Deferred lease incentive, current portion 328 324 Deferred rent, current portion 127 102 Interest payable 164 — $ 3,909 $ 3,853

Asset Purchase Agreement

Asset Purchase Agreement	6 Months Ended
	Jun. 30, 2017
Discontinued Operations and Disposal Groups [Abstract]
Asset Purchase Agreement	Asset Purchase Agreement On March 3, 2017, the Company, Vertex Pharmaceuticals (Europe) Limited, a U.K. limited company (“Vertex”), and Vertex Pharmaceuticals Inc., a Massachusetts corporation, solely as a guarantor, entered into an Asset Purchase Agreement, pursuant to which, subject to the satisfaction or waiver of the conditions therein, the Company sold and assigned to Vertex, CTP-656 and other cystic fibrosis assets of the Company. On May 24, 2017, Concert shareholders authorized the sale of CTP-656 and other assets related to the treatment of cystic fibrosis. In July 2017 the FTC terminated the waiting period for the pending sale of CTP-656 under the HSR Act of 1976. The expiration of the HSR Act waiting period represented the final regulatory closing condition required to complete the Asset Purchase Agreement. In July 2017, the Asset Purchase Agreement closed and Vertex paid the Company $160 million in cash consideration, with $16 million to initially be held in escrow. The Company will recognize this subsequent event in the third quarter of fiscal 2017. Accordingly, no accounting consideration has been given to the asset sale as of June 30, 2017. Additionally, upon the achievement of certain milestone events, Vertex has agreed to pay the Company an aggregate of up to $90 million . Of this amount, $50 million will become payable to the Company upon receipt of FDA marketing approval for a combination treatment regimen containing CTP-656 for patients with cystic fibrosis, and $40 million will become payable to the Company upon completion of a pricing and reimbursement agreement in the first of the United Kingdom, Germany or France with respect to a combination treatment regimen containing CTP-656 for patients with cystic fibrosis. Pursuant to the Asset Purchase Agreement, the Company has agreed to indemnify Vertex for certain matters, including breaches of specified representations and warranties, covenants included in the Asset Purchase Agreement and specified tax claims. Representations and warranties, other than certain fundamental representations and warranties, survive for a period of eighteen months following the Closing and the maximum liability of the Company for claims by Vertex related to the breaches of such representations and warranties, with limited exceptions, is limited to the escrow amount, or $16 million . In no event will the aggregate liability of the Company for indemnification exceed the purchase price paid by Vertex, including any milestone payments. Eighteen months after the Closing, any remaining balance in the escrow account not subject to indemnity claims by Vertex will be released to the Company.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Deferred tax assets and deferred tax liabilities are recognized based on temporary differences between the financial reporting and tax basis of assets and liabilities using statutory rates. A valuation allowance is recorded against deferred tax assets if it is more likely than not that some or all of the deferred tax assets will not be realized. The Company records a provision or benefit for income taxes on ordinary pre-tax income or loss based on its estimated effective tax rate for the year. As of June 30, 2017, the Company forecast an ordinary pre-tax loss for the year ended December 31, 2017 and, since it maintains a full valuation allowance on its deferred tax assets, the Company did not record an income tax benefit for the six months ended June 30, 2017. In July 2017, the Asset Purchase Agreement described in Note 6 closed and Vertex paid the Company $160 million in cash consideration, with $16 million of such consideration to initially be held in escrow. The Company will recognize this subsequent event in the third quarter of fiscal 2017 and the cash consideration will be included in the Company's estimated effective tax rate in the third quarter of 2017. The effect of a non-recognized subsequent event is considered in the Company's estimated effective tax rate in the period in which the event occurs. Accordingly, no income tax provision or benefit was recorded during the quarter or six month period ended June 30, 2017 as a result of the closing of the asset purchase with Vertex in July 2017. The Company’s ability to use its operating loss carryforwards and tax credits to offset future taxable income is subject to restrictions under Sections 382 and 383 of the United States Internal Revenue Code (the “Internal Revenue Code”). Net operating loss and tax credit carryforwards may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant shareholders over a three-year period in excess of 50 percent, as defined under Sections 382 and 383 of the Internal Revenue Code. Such changes would limit the Company’s use of its operating loss carryforwards and tax credits. In such a situation, the Company may be required to pay income taxes, even though significant operating loss carryforwards and tax credits exist. The Company is currently in the process of evaluating the extent of any such ownership changes and annual limitations under Section 382 and 383 of the Internal Revenue Code.

Collaborations

Collaborations	6 Months Ended
	Jun. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Collaborations	Collaborations Celgene In April 2013, the Company entered into a master development and license agreement with Celgene Corporation and Celgene International Sàrl, referred to together as Celgene, which is primarily focused on the research, development and commercialization of specified deuterated compounds targeting inflammation or cancer. The initial program in the collaboration is CTP-730, a deuterium-modified analog of apremilast. Celgene has an exclusive worldwide license to develop, manufacture and commercialize deuterated analogs of apremilast and certain close chemical derivatives thereof. The Company further granted Celgene licenses with respect to two additional programs and an option with respect to a third additional program. The Company was responsible for conducting and funding research and early development activities for the CTP-730 program at its own expense pursuant to mutually agreed upon development plans. This included the completion of single and multiple ascending dose Phase 1 clinical trials in 2015. Under the terms of the agreement, the Company received a non-refundable upfront payment of $35.0 million . In October 2015, the Company earned and recognized as milestone revenue an $8.0 million development milestone based on the completion of Phase 1 clinical evaluation of CTP-730. In addition, the Company is eligible to earn an additional $15.0 million development milestone payment, up to $247.5 million in regulatory milestone payments and up to $50.0 million in sales-based milestone payments related to products within the CTP-730 program. The next milestone payment the Company may be entitled to achieve under the CTP-730 program is $15.0 million related to the first actual dosing in a Phase 3 clinical trial or, if earlier, acceptance for filing of a new drug application, or NDA. If Celgene exercises its rights with respect to either of the two additional license programs, the Company will receive a license exercise fee for the applicable program of $30.0 million and will also be eligible to earn up to $23.0 million in development milestone payments and up to $247.5 million in regulatory milestone payments for that program. Additionally, with respect to one of the additional license programs, the Company is eligible to receive up to $100.0 million in milestone payments based on net sales of products, and with respect to the other additional license program, the Company is eligible to receive up to $50.0 million in milestone payments based on net sales of products. If Celgene exercises its option with respect to the option program, in respect of a compound to be identified at a later time, the Company will receive an option exercise fee of $10.0 million and will be eligible to earn up to $23.0 million in development milestone payments and up to $247.5 million in regulatory milestone payments. In addition, with respect to each program, Celgene is required to pay the Company royalties on worldwide net sales of each licensed product at defined percentages ranging from the mid-single digits to low double digits below 20% . The royalty rate is reduced on a country-by-country basis during any period within the royalty term when there is no patent claim or regulatory exclusivity covering the licensed product in the particular country. During the three months ended June 30, 2017, the Company did not recognize any revenue for the R&D Services and Supply Deliverables, as no services were performed. During the three months ended June 30, 2016, the Company recognized revenue of $11 thousand for the R&D Services Deliverable and $18 thousand for the Supply Deliverable, respectively. During the six months ended, June 30, 2017 and 2016, the Company recognized revenue of $2 thousand and $19 thousand for the R&D Services Deliverable and $10 thousand and $38 thousand for the Supply Deliverable, respectively. The revenue was classified as license and research and development revenue in the accompanying condensed consolidated statements of operations and comprehensive loss. As of June 30, 2017, there was $7.2 million of deferred revenue related to the Company’s collaboration with Celgene, $1.1 million of which was classified as a current liability and $6.1 million o f which was classified as a noncurrent liability, in the accompanying condensed consolidated balance sheet. Jazz Pharmaceuticals In February 2013, the Company entered into a development and license agreement with Jazz Pharmaceuticals, Inc., or Jazz Pharmaceuticals, to research, develop and commercialize products containing a deuterated sodium oxybate analog, or D-SXB. Jazz Pharmaceuticals is initially focusing on one analog, designated as JZP-386. Under the terms of the agreement, the Company granted Jazz Pharmaceuticals an exclusive, worldwide, royalty-bearing license under intellectual property controlled by the Company to develop, manufacture and commercialize D-SXB products including, but not limited to, JZP-386. The Company, together with Jazz Pharmaceuticals, has conducted certain development activities for Phase 1 clinical trials with respect to JZP-386 pursuant to an agreed upon development plan. The Company was responsible under the development plan for conducting the Phase 1 clinical trials with respect to JZP-386. The Company’s obligations to conduct further development activities are subject to mutual agreement. Jazz Pharmaceuticals has assumed all manufacturing and development responsibilities relating to JZP-386. Pursuant to the agreement, the Company’s costs for activities under the development plan were reimbursed by Jazz Pharmaceuticals, except for the costs of a Phase 1 clinical trial that was conducted in the first half of 2015, which was shared between Jazz Pharmaceuticals and the Company. Under the agreement, the Company received a non-refundable upfront payment of $4.0 million and is eligible to earn an aggregate of up to $8.0 million in development milestone payments, up to $35.0 million in regulatory milestone payments and up to $70.0 million in sales-based milestone payments based on net product sales of licensed products. The next milestone payment that the Company may be entitled to receive is $4.0 million related to initiation of the first Phase 2 clinical trial of JZP-386. In addition, Jazz Pharmaceuticals is required to pay the Company royalties at defined percentages ranging from the mid-single digits to low double digits below 20% on worldwide net sales of licensed products. The royalty rate is lowered, on a country-by-country basis, under certain circumstances as specified in the agreement. For the three months ended June 30, 2017 and 2016, the Company recognized revenue of $15 thousand and $34 thousand respectively, related to the performance of development support services. For the six months ended June 30, 2017 and 2016, the Company recognized revenue of $22 thousand and $68 thousand related to the performance of development support services, respectively. Avanir In February 2012, the Company entered into a development and license agreement with Avanir Pharmaceuticals, Inc., or Avanir, under which the Company granted Avanir an exclusive worldwide license to develop, manufacture and commercialize deudextromethorphan containing products. Avanir is currently focused on developing AVP-786, which is a combination of a deudextromethorphan and an ultra low dose of quinidine. Subsequent to the Company’s agreement, Avanir was acquired by Otsuka Pharmaceutical Co., Ltd. and it is now a wholly owned subsidiary of Otsuka America, Inc. Since June 2012, Avanir has elected to conduct all research and development activities, including manufacturing activities; however, the Company has received intellectual property cost reimbursements. Under the agreement, the Company received a non-refundable upfront payment of $2.0 million and has received milestone payments of $6.0 million . The Company is also eligible to earn, with respect to licensed products comprising a combination of deudextromethorphan and quinidine, up to $37.0 million in regulatory and commercial launch milestone payments, of which $21.5 million in development and regulatory milestone payments are associated with the first indication, and up to $125.0 million in sales-based milestone payments. The next milestone payments that the Company may be entitled to receive are $5.0 million upon acceptance for filing of a NDA, $3.0 million upon acceptance for filing of a Marketing Authorization Application, or MAA, and $1.5 million upon acceptance for filing of a NDA by the Ministry of Health, Labour and Welfare, or MHLW, related to AVP-786. In addition, the Company is eligible for higher development milestones, up to an additional $43.0 million , for licensed products that do not require quinidine. Avanir is currently developing deudextromethorphan only in combination with quinidine. Avanir also is required to pay the Company royalties at defined percentages ranging from the mid-single digits to low double digits below 20% on net sales of licensed products on a country-by-country basis. The royalty rate is reduced, on a country-by-country basis, during any period within the royalty term when there is no patent claim covering the licensed product in the particular country.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation The Company’s equity incentive plans provide for the issuance of a variety of stock-based awards, including incentive stock options, nonstatutory stock options and awards of stock, to directors, officers and employees of the Company, as well as consultants and advisors to the Company. As of June 30, 2017, the Company has granted awards solely in the form of stock options, which have generally been granted with an exercise price equal to the fair value of the underlying common stock on the date of grant, expire no later than ten years from the date of grant and generally vest over three or four years. Effective January 1, 2017, an additional 892,679 shares were added to the Company’s 2014 Stock Incentive Plan, or the 2014 Plan, for future issuance pursuant to the terms of the 2014 Plan. As of June 30, 2017, there were 1,709,515 shares of common stock available for future award grants under the 2014 Plan. Total stock-based compensation expense related to all stock-based awards recognized in the condensed consolidated statements of operations and comprehensive loss consisted of: Three Months Ended June 30, Six Months Ended June 30, 2017 2016 2017 2016 Research and development $ 686 $ 553 $ 1,403 $ 1,106 General and administrative 887 734 1,813 1,463 Total stock-based compensation expense $ 1,573 $ 1,287 $ 3,216 $ 2,569 Stock Options Stock options are valued using the Black-Scholes-Merton option valuation model and compensation cost is recognized based on such fair value over the period of vesting. The weighted average fair value of options granted in the three and six months ended June 30, 2017 and 2016 reflect the following weighted-average assumptions: Three Months Ended Six Months Ended June 30, 2017 2016 2017 2016 Expected volatility 78.30 % 78.12 % 78.16 % 78.31 % Expected term 6.0 years 6.0 years 6.0 years 6.0 years Risk-free interest rate 2.02 % 1.15 % 2.07 % 1.35 % Expected dividend yield — % — % — % — % For the three and six months ended June 30, 2017, expected volatility was estimated using a weighted-average of the Company's historical volatility of its common stock and the historical volatility of the common stock of a group of similar companies that were publicly traded. The Company will continue to apply this process until a sufficient amount of historical information regarding the volatility of its own stock price becomes available. For the three and six months ended June 30, 2016, expected volatility was estimated using the historical volatility of the common stock of a group of similar companies that were publicly traded. The following table provides certain information related to the Company's outstanding stock options: Three Months Ended June 30, Six Months Ended June 30, 2017 2016 2017 2016 (in thousands, except per share data) Weighted average fair value of options granted, per option $ 9.29 $ 8.72 $ 7.66 $ 10.91 Aggregate grant date fair value of options vested during the period $ 1,691 $ 1,352 $ 2,967 $ 2,384 Total cash received from exercises of stock options $ 317 $ 63 $ 1,456 $ 239 Total intrinsic value of stock options exercised $ 645 $ 131 $ 3,309 $ 628 The following is a summary of stock option activity for the six months ended June 30, 2017: Number of Option Shares Weighted Average Exercise Price per Share Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (In years) (In thousands) Outstanding at December 31, 2016 2,953,961 $ 10.49 Granted 1,059,300 $ 11.23 Exercised (301,306 ) $ 4.96 Forfeited or expired (174,685 ) $ 12.17 Outstanding at June 30, 2017 3,537,270 $ 11.10 6.84 $ 12,333 Exercisable at June 30, 2017 1,747,298 $ 9.57 5.41 $ 8,527 Vested and expected to vest at June 30, 2017 (1) 3,371,158 $ 11.03 6.76 $ 11,966 (1) This represents the number of vested stock option shares as of June 30, 2017, plus the number of unvested stock option shares that the Company estimated as of June 30, 2017 would vest, based on the unvested stock option shares at June 30, 2017 and an estimated forfeiture rate of 7% . As of June 30, 2017, there was $13.2 million of unrecognized compensation cost related to stock options that are expected to vest. These costs are expected to be recognized over a weighted average remaining vesting period of 2.7 years .

Earnings (Loss) Per Share

Earnings (Loss) Per Share	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Earnings (Loss) Per Share	Earnings (Loss) Per Share Basic net earnings (loss) per common share is calculated by dividing net earnings (loss) allocable to common stockholders by the weighted-average common shares outstanding during the period, without consideration of common stock equivalents. Diluted net earnings per share is calculated by adjusting the weighted-average shares outstanding for the dilutive effect of common stock equivalents, including stock options and warrants, outstanding for the period as determined using the treasury stock method. For purposes of the diluted net loss per share calculation, common stock equivalents are excluded from the calculation if their effect would be anti-dilutive. Therefore, basic and diluted net loss per share applicable to common stockholders is the same for periods with a net loss. Three Months Ended June 30, Six Months Ended 2017 2016 2017 2016 (in thousands, expect per share amounts) Numerator: Net loss applicable to common stockholders - basic and diluted (13,027 ) $ (13,441 ) (26,360 ) $ (27,321 ) Denominator: Weighted average shares outstanding - basic 22,579 22,217 22,479 22,208 Dilutive stock options — — — — Dilutive warrants — — — — Weighted average shares outstanding - diluted 22,579 22,217 22,479 22,208 Net loss per share applicable to common stockholders - basic and diluted $ (0.58 ) $ (0.60 ) $ (1.17 ) $ (1.23 ) Anti-dilutive potential common stock equivalents excluded from the calculation of net loss per share: Stock options 637 667 610 717 Warrants 132 71 132 71

Loan Payable and Warrant to Pur

Loan Payable and Warrant to Purchase Common Stock	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Loan Payable and Warrant to Purchase Common Stock	Loan Payable and Warrant to Purchase Common Stock On June 8, 2017, the Company entered into a Loan and Security Agreement, or the Loan Agreement, with Hercules Capital, Inc., or Hercules, pursuant to which Hercules agreed to make available to the Company a secured term loan facility in the amount of $30.0 million , or the Term Loan Facility, subject to certain terms and conditions. The Company borrowed $30 million under the Loan Agreement in one advance. The Company incurred $0.3 million in loan issuance costs paid directly to the lenders, which have been offset against the loan proceeds as a loan discount. The advance under the Loan and Security Agreement bears interest at a variable rate of the greater of 8.55% and an amount equal to 8.55% plus the prime rate of interest minus 4.50% . Through June 30, 2017, the Notes had an interest rate of 8.55% . Interest-only payments are due monthly on the first day of each month beginning the month after the date of the advance until January 1, 2019. Thereafter the aggregate principal balance outstanding becomes payable in 30 equal monthly installments of principal and interest continuing through the maturity date of June 1, 2021. The Company may prepay the principal of the Loan Agreement at any time subject to a prepayment charge equal to: 2.0% of amounts prepaid on or prior to June 1, 2018; 1.0% of amounts prepaid during the period from June 1, 2018 to June 1, 2019; and 0.5% of amounts prepaid on and after June 1, 2019. The Prepayment Charge will be waived if the Company completes the sale of CTP-656 to Vertex Pharmaceuticals, discussed further in Note 6, and prepays the Notes after the 90 th day following the closing date of the Loan Agreement but prior to the six month anniversary of the closing date of the Loan Agreement. The Company evaluated the embedded features inherent in the Loan Agreement to determine if any of the embedded features require bifurcation and, therefore, separate accounting as a derivative liability. As a result of the Company’s determination that the prepayment features are clearly and closely related to the debt host, bifurcation and separate accounting is not required. The Company will pay an End of Term Charge of $1.5 million on the date that the Notes are paid in full or become due and payable. The Company is amortizing the End of Term Charge over the life of the loan. The End of Term Charge will be reduced to $0.7 million if the Company completes the sale of CTP-656 to Vertex Pharmaceuticals and prepays the Notes after the 90 th day following the closing date of the Loan Agreement but prior to the six month anniversary of the closing date of the Loan Agreement. The Loan Agreement is secured by substantially all of the Company’s assets, including all securities in domestic subsidiaries and 65% of the securities in foreign subsidiaries, but excluding its intellectual property, and subject to certain exceptions and exclusions. Future principal payments, which exclude the end of term charge, in connection with the Loan and Security Agreement, as of June 30, 2017 are as follows (in thousands): Fiscal Year Principal Payments 2017 $ — 2018 — 2019 11,209 2020 12,216 2021 6,575 Total 30,000 In connection with the entry into the Loan Agreement, the Company issued warrants, or the Warrants, to certain entities affiliated with Hercules, exercisable for an aggregate of 61,273 shares of the Company’s common stock at an exercise price of $12.24 per share. The Warrants have a five year term, expiring June 8, 2022, and may be exercised on a cashless basis. The Hercules Warrants have a total relative fair value of $0.5 million . Pursuant to ASC Topic 480, Distinguishing Liabilities from Equity and ASC Topic 815, Derivatives and Hedging , the Warrants were classified as equity and were measured at relative fair value. Subsequent changes to fair value will not be recognized so long as the instrument continues to be equity classified. To determine the relative fair value, the Company measured the fair value of the Warrants as of June 8, 2017 using the Black-Scholes-Merton option pricing model. The significant assumptions used in estimating the fair value of the Warrants include the volatility of the stock underlying the warrants, risk-free interest rate, and estimated life of the warrant. The Company used the following weighted-average assumptions: Expected volatility 73.71 % Expected term (in years) 5 Risk-free interest rate 1.75 % Expected dividend yield — % Consistent with the Company’s weighted-average assumptions used in determining the fair value of options, expected volatility was estimated using a weighted-average of the Company's historical volatility of its common stock and the historical volatility of the common stock of a group of similar companies that were publicly traded.

Basis of Presentation and Sig17

Basis of Presentation and Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2017
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and with 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 generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments, consisting of normal recurring accruals and revisions of estimates, considered necessary for a fair presentation of the condensed consolidated financial statements have been included. Interim results for the three and six months ended June 30, 2017 are not necessarily indicative of the results that may be expected for the fiscal year ending December 31, 2017 or any other future period. The accompanying condensed consolidated financial statements reflect the accounts of Concert and its subsidiaries. All intercompany transactions between the Company and its subsidiaries have been eliminated. Management has determined that the Company operates in one segment: the development of pharmaceutical products on its own behalf or in collaboration with others. The information included in this quarterly report on Form 10-Q should be read in conjunction with the Company’s consolidated financial statements and the accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 filed with the Securities and Exchange Commission on March 6, 2017.
Use of Estimates and Summary of Significant Accounting Policies	Use of Estimates and Summary of Significant Accounting Policies In preparing the condensed consolidated financial statements, management used estimates in the following areas, among others: revenue recognition for multiple-element revenue arrangements; stock-based compensation expense; income tax expense; accrued expenses; and the evaluation of the existence of conditions and events that raise substantial doubt regarding the Company’s ability to continue as a going concern. Actual results could differ from those estimates. There have been no material changes to the significant accounting policies previously disclosed in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2016.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the Financial Accounting Standard Board, or FASB, issued Accounting Standards Update, or ASU, No. 2014-09, Revenue from Contracts with Customers (Topic 606), or ASU 2014-09, which stipulates that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve this core principle, ASU 2014-09 provides that an entity should apply the following steps: (1) identify the contract(s) with a customer, (2) identify the performance obligations in the contract, (3) determine the transaction price, (4) allocate the transaction price to the performance obligations in the contract and (5) recognize revenue when (or as) the entity satisfies a performance obligation. This update will be effective for the Company beginning in the first quarter of fiscal 2018 as a result of the FASB’s one year deferral of the effective date for this standard. The amendments may be applied retrospectively to each prior period (full retrospective) or retrospectively with the cumulative effect recognized as of the date of initial application (modified retrospective). Previously, the Company disclosed that it intended to apply ASU 2014-09 using the full retrospective approach. Due to the additional adoption efforts required of issuers under the full retrospective approach, the Company now intends to adopt ASU 2014-09 in the first quarter of 2018 using the modified retrospective approach. Under the modified retrospective approach, the cumulative effect of applying the standard would be recognized at the date of initial application within retained earnings. The Company is currently evaluating the effect of adopting the requirements of ASU 2014-09 as it relates to the accounting for its collaboration arrangements with Celgene Pharmaceuticals, Inc., Jazz Pharmaceuticals plc and Avanir Pharmaceuticals, Inc., and its patent assignment agreement with Auspex Pharmaceuticals, Inc. The Company is also in the process of evaluating appropriate changes to its controls to support revenue recognition and disclosure under the new standard. In August 2014, the FASB issued ASU No. 2014-15, Disclosure of Uncertainties About an Entity’s Ability to Continue as a Going Concern, or ASU 2014-15. ASU 2014-15 amends FASB Accounting Standards Codification, or ASC, 205-40, Presentation of Financial Statements – Going Concern, by providing guidance on determining when and how reporting entities must disclose going-concern uncertainties in their financial statements, including requiring management to perform interim and annual assessments of an entity’s ability to continue as a going concern within one year of the date of issuance of the entity’s financial statements and providing certain disclosures if there is substantial doubt about the entity’s ability to continue as a going concern. The Company was required to apply the requirements of ASU 2014-15 in its interim financial statements beginning in the first quarter of fiscal 2017. With respect to the interim financial statements as of June 30, 2017, the Company did not identify any conditions or events that raise substantial doubt about its ability to continue as a going concern within one year after the date the financial statements are issued. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), or ASU 2016-02. ASU 2016-02 requires lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by all leases with terms of more than 12 months. ASU 2016-02 also will require certain qualitative and quantitative disclosures designed to give financial statement users information on the amount, timing, and uncertainty of cash flows arising from leases. ASU 2016-02 will be effective for the Company on January 1, 2019, with early adoption permitted. The Company is currently evaluating the impact ASU 2016-02 will have on its financial statements. In March 2016, the FASB issued ASU No. 2016-09, Compensation-Stock Compensation-Improvements to Employee Share-Based Payment Accounting, or ASU 2016-09. This update simplifies several aspects of the accounting for share-based compensation arrangements, including accounting for income taxes, forfeitures and statutory tax withholding requirements as well as classification of related amounts on the statement of cash flows. The Company adopted this ASU on January 1, 2017 and it did not have a material effect on the consolidated financial statements and related disclosures. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326)-Measurement of Credit Losses on Financial Instruments, or ASU 2016-13. The new standard requires entities to measure all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions and reasonable and supportable forecasts. ASU 2016-13 will become effective for the Company for fiscal years beginning after December 15, 2019, with early adoption permitted. The Company is currently evaluating the impact ASU 2016-13 will have on its financial statements and related disclosures.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Financial Assets and Liabilities Recognized at Fair Value	The tables below present information about the Company’s financial assets and liabilities that are measured and carried at fair value as of June 30, 2017 and December 31, 2016 (in thousands) and indicate the level within the fair value hierarchy where each measurement is classified. Level 1 Level 2 Level 3 Total June 30, 2017 Cash equivalents: Money market funds $ 23,790 $ — $ — $ 23,790 Investments, available for sale: U.S. Treasury obligations 21,527 — — 21,527 Government agency securities 53,304 998 — 54,302 Total $ 98,621 $ 998 $ — $ 99,619 Level 1 Level 2 Level 3 Total December 31, 2016 Cash equivalents: Money market funds $ 26,257 $ — $ — $ 26,257 U.S. Treasury obligations — 1,001 — 1,001 Investments, available for sale: U.S. Treasury obligations 10,034 5,503 — 15,537 Government agency securities 24,545 15,548 — 40,093 Total $ 60,836 $ 22,052 $ — $ 82,888

Cash, Cash Equivalents and In19

Cash, Cash Equivalents and Investments (Tables)	6 Months Ended
	Jun. 30, 2017
Cash and Cash Equivalents [Abstract]
Cash Equivalents and Short-term and Long-term Investments	Cash, cash equivalents and investments, available for sale included the following at June 30, 2017 and December 31, 2016: Average maturity Amortized cost Unrealized gains Unrealized losses Fair value June 30, 2017 Cash $ 3,801 $ — $ — $ 3,801 Money market funds 23,790 — — 23,790 Cash and cash equivalents $ 27,591 $ — $ — $ 27,591 U.S. Treasury obligations 184 days 21,544 — (17 ) 21,527 Government agency securities 187 days 54,329 — (27 ) 54,302 Investments, available for sale $ 75,873 $ — $ (44 ) $ 75,829 Average maturity Amortized cost Unrealized gains Unrealized losses Fair value December 31, 2016 Cash $ 13,297 $ — $ — $ 13,297 Money market funds 26,257 — — 26,257 U.S. Treasury obligations 31 days 1,001 — — 1,001 Cash and cash equivalents $ 40,555 $ — $ — $ 40,555 U.S. Treasury obligations 125 days 15,534 4 (1 ) 15,537 Government agency securities 140 days 40,103 1 (11 ) 40,093 Investments, available for sale $ 55,637 $ 5 $ (12 ) $ 55,630

Accrued Expenses and Other Li20

Accrued Expenses and Other Liabilities (Tables)	6 Months Ended
	Jun. 30, 2017
Payables and Accruals [Abstract]
Accrued Expenses and Other Liabilities	Accrued expenses and other liabilities consisted of the following: June 30, December 31, Accrued professional fees and other $ 1,366 $ 487 Employee compensation and benefits 1,320 2,010 Research and development expenses 604 930 Deferred lease incentive, current portion 328 324 Deferred rent, current portion 127 102 Interest payable 164 — $ 3,909 $ 3,853

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation Expense Related to All Stock Based Awards Recognized in Statements of Operations and Comprehensive Income (Loss)	Total stock-based compensation expense related to all stock-based awards recognized in the condensed consolidated statements of operations and comprehensive loss consisted of: Three Months Ended June 30, Six Months Ended June 30, 2017 2016 2017 2016 Research and development $ 686 $ 553 $ 1,403 $ 1,106 General and administrative 887 734 1,813 1,463 Total stock-based compensation expense $ 1,573 $ 1,287 $ 3,216 $ 2,569
Estimated Weighted-Average Assumptions of Options Granted	The weighted average fair value of options granted in the three and six months ended June 30, 2017 and 2016 reflect the following weighted-average assumptions: Three Months Ended Six Months Ended June 30, 2017 2016 2017 2016 Expected volatility 78.30 % 78.12 % 78.16 % 78.31 % Expected term 6.0 years 6.0 years 6.0 years 6.0 years Risk-free interest rate 2.02 % 1.15 % 2.07 % 1.35 % Expected dividend yield — % — % — % — %
Certain Information Related to Outstanding Stock Options	The following table provides certain information related to the Company's outstanding stock options: Three Months Ended June 30, Six Months Ended June 30, 2017 2016 2017 2016 (in thousands, except per share data) Weighted average fair value of options granted, per option $ 9.29 $ 8.72 $ 7.66 $ 10.91 Aggregate grant date fair value of options vested during the period $ 1,691 $ 1,352 $ 2,967 $ 2,384 Total cash received from exercises of stock options $ 317 $ 63 $ 1,456 $ 239 Total intrinsic value of stock options exercised $ 645 $ 131 $ 3,309 $ 628
Summary of Stock Option Activity	The following is a summary of stock option activity for the six months ended June 30, 2017: Number of Option Shares Weighted Average Exercise Price per Share Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (In years) (In thousands) Outstanding at December 31, 2016 2,953,961 $ 10.49 Granted 1,059,300 $ 11.23 Exercised (301,306 ) $ 4.96 Forfeited or expired (174,685 ) $ 12.17 Outstanding at June 30, 2017 3,537,270 $ 11.10 6.84 $ 12,333 Exercisable at June 30, 2017 1,747,298 $ 9.57 5.41 $ 8,527 Vested and expected to vest at June 30, 2017 (1) 3,371,158 $ 11.03 6.76 $ 11,966 (1) This represents the number of vested stock option shares as of June 30, 2017, plus the number of unvested stock option shares that the Company estimated as of June 30, 2017 would vest, based on the unvested stock option shares at June 30, 2017 and an estimated forfeiture rate of 7% .

Earnings (Loss) Per Share (Tabl

Earnings (Loss) Per Share (Tables)	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings (Loss) Per Share	Three Months Ended June 30, Six Months Ended 2017 2016 2017 2016 (in thousands, expect per share amounts) Numerator: Net loss applicable to common stockholders - basic and diluted (13,027 ) $ (13,441 ) (26,360 ) $ (27,321 ) Denominator: Weighted average shares outstanding - basic 22,579 22,217 22,479 22,208 Dilutive stock options — — — — Dilutive warrants — — — — Weighted average shares outstanding - diluted 22,579 22,217 22,479 22,208 Net loss per share applicable to common stockholders - basic and diluted $ (0.58 ) $ (0.60 ) $ (1.17 ) $ (1.23 ) Anti-dilutive potential common stock equivalents excluded from the calculation of net loss per share: Stock options 637 667 610 717 Warrants 132 71 132 71

Loan Payable and Warrant to P23

Loan Payable and Warrant to Purchase Common Stock (Tables)	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Loan Payable Future Minimum Payments	Future principal payments, which exclude the end of term charge, in connection with the Loan and Security Agreement, as of June 30, 2017 are as follows (in thousands): Fiscal Year Principal Payments 2017 $ — 2018 — 2019 11,209 2020 12,216 2021 6,575 Total 30,000
Summary of Significant Assumptions Used in Warrant Fair Value Measurements	The Company used the following weighted-average assumptions: Expected volatility 73.71 % Expected term (in years) 5 Risk-free interest rate 1.75 % Expected dividend yield — %

Nature of Business - Additional

Nature of Business - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2017	Jun. 08, 2017	Mar. 03, 2017	Dec. 31, 2016
Subsidiary, Sale of Stock [Line Items]
Cash and cash equivalents and investments	$ 103,400,000
Period of sufficiency of cash resources to fund operating plan	12 months
Accumulated deficit	$ (198,242,000)			$ (171,882,000)
Assets for synthesis and research and development for treating Cystic Fibrosis | Disposed of by sale, not discontinued operations
Subsidiary, Sale of Stock [Line Items]
Consideration transferred			$ 250,000,000
Cash consideration			160,000,000
Loan Agreement | Secured Term Loan Facility | Line of Credit
Subsidiary, Sale of Stock [Line Items]
Secured term loan facility amount		$ 30,000,000
Indemnification agreement | Assets for synthesis and research and development for treating Cystic Fibrosis | Disposed of by sale, not discontinued operations
Subsidiary, Sale of Stock [Line Items]
Guarantor maximum liability			$ 16,000,000

Basis of Presentation and Sig25

Basis of Presentation and Significant Accounting Policies - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2017segment
Accounting Policies [Abstract]
Number of segments	1

Fair Value Measurements - Finan

Fair Value Measurements - Financial Assets and Liabilities Recognized at Fair Value (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Fair value measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets at fair value	$ 99,619	$ 82,888
Fair value measurements | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets at fair value	98,621	60,836
Fair value measurements | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets at fair value	998	22,052
Fair value measurements | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets at fair value	0	0
Shorter maturity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, investments available-for-sale securities	27,591	40,555
Shorter maturity | Fair value measurements | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, cash equivalents	23,790	26,257
Shorter maturity | Fair value measurements | Money market funds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, cash equivalents	23,790	26,257
Shorter maturity | Fair value measurements | Money market funds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, cash equivalents	0	0
Shorter maturity | Fair value measurements | Money market funds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, cash equivalents	0	0
Shorter maturity | Fair value measurements | U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, cash equivalents		1,001
Shorter maturity | Fair value measurements | U.S. Treasury obligations | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, cash equivalents		0
Shorter maturity | Fair value measurements | U.S. Treasury obligations | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, cash equivalents		1,001
Shorter maturity | Fair value measurements | U.S. Treasury obligations | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, cash equivalents		0
Longer maturity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, investments available-for-sale securities	75,829	55,630
Longer maturity | Fair value measurements | U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, investments available-for-sale securities	21,527	15,537
Longer maturity | Fair value measurements | U.S. Treasury obligations | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, investments available-for-sale securities	21,527	10,034
Longer maturity | Fair value measurements | U.S. Treasury obligations | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, investments available-for-sale securities	0	5,503
Longer maturity | Fair value measurements | U.S. Treasury obligations | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, investments available-for-sale securities	0	0
Longer maturity | Fair value measurements | Government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, investments available-for-sale securities	54,302	40,093
Longer maturity | Fair value measurements | Government agency securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, investments available-for-sale securities	53,304	24,545
Longer maturity | Fair value measurements | Government agency securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, investments available-for-sale securities	998	15,548
Longer maturity | Fair value measurements | Government agency securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, investments available-for-sale securities	$ 0	$ 0

Cash, Cash Equivalents and In27

Cash, Cash Equivalents and Investments (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost, cash and cash equivalents	$ 27,591	$ 40,555	$ 53,651	$ 92,510
Cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost, investments available for sale	27,591	40,555
Unrealized gains	0	0
Unrealized losses	0	0
Fair value, available-for-sale securities	27,591	40,555
Investments, available for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost, investments available for sale	75,873	55,637
Unrealized gains	0	5
Unrealized losses	(44)	(12)
Fair value, available-for-sale securities	75,829	55,630
Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost, cash and cash equivalents	3,801	13,297
Fair value, cash and cash equivalent	3,801	13,297
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost, cash and cash equivalents	23,790	26,257
Fair value, cash and cash equivalent	$ 23,790	$ 26,257
U.S. Treasury obligations | Cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Expected term (in years)		31 days
Amortized cost, investments available for sale		$ 1,001
Unrealized gains		0
Unrealized losses		0
Fair value, available-for-sale securities		$ 1,001
U.S. Treasury obligations | Investments, available for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Expected term (in years)	184 days	125 days
Amortized cost, investments available for sale	$ 21,544	$ 15,534
Unrealized gains	0	4
Unrealized losses	(17)	(1)
Fair value, available-for-sale securities	$ 21,527	$ 15,537
Government agency securities | Investments, available for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Expected term (in years)	187 days	140 days
Amortized cost, investments available for sale	$ 54,329	$ 40,103
Unrealized gains	0	1
Unrealized losses	(27)	(11)
Fair value, available-for-sale securities	$ 54,302	$ 40,093

Cash, Cash Equivalents and In28

Cash, Cash Equivalents and Investments - Additional Information (Detail) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Cash and Cash Equivalents [Abstract]
Realized gains or losses on sales of investments	$ 0	$ 0
Other than temporary impairment losses, investments	$ 0	$ 0

Accrued Expenses and Other Li29

Accrued Expenses and Other Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Accrued professional fees and other	$ 1,366	$ 487
Employee compensation and benefits	1,320	2,010
Research and development expenses	604	930
Deferred lease incentive, current portion	328	324
Deferred rent, current portion	127	102
Interest payable	164	0
Accrued expenses and other liabilities	$ 3,909	$ 3,853

Asset Purchase Agreement (Detai

Asset Purchase Agreement (Details) - Disposed of by sale, not discontinued operations - Assets for synthesis and research and development for treating Cystic Fibrosis	Mar. 03, 2017USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash consideration	$ 160,000,000
Contingent consideration asset, After achievement of milestone events
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Contingent consideration receivable	90,000,000
Contingent consideration asset, Upon receipt of FDA marketing approval
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Contingent consideration receivable	50,000,000
Contingent consideration asset, Upon completion of pricing and reimbursement agreement
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Contingent consideration receivable	40,000,000
Indemnification agreement
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Guarantor maximum liability	$ 16,000,000
Guarantor obligations term	18 months

Income Taxes Income Taxes (Deta

Income Taxes Income Taxes (Details) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Jun. 30, 2016	Mar. 03, 2017
Schedule Of Income Taxes [Line Items]
Income tax provision or benefit	$ 0	$ 0	$ 0
Disposed of by sale, not discontinued operations | Assets for synthesis and research and development for treating Cystic Fibrosis
Schedule Of Income Taxes [Line Items]
Cash consideration				$ 160,000,000
Indemnification agreement | Disposed of by sale, not discontinued operations | Assets for synthesis and research and development for treating Cystic Fibrosis
Schedule Of Income Taxes [Line Items]
Guarantor maximum liability				$ 16,000,000

Collaborations - Celgene - Addi

Collaborations - Celgene - Additional Information (Detail)	1 Months Ended	3 Months Ended		6 Months Ended
	Apr. 30, 2013USD ($)licenseoption	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Dec. 31, 2016USD ($)	Oct. 30, 2015USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Deferred revenue, current portion		$ 1,168,000		$ 1,168,000		$ 1,172,000
License, research and development revenue		15,000	$ 71,000	35,000	$ 127,000
Deferred revenue, noncurrent		8,857,000		8,857,000		$ 8,878,000
Celgene
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of additional license program | license	2
Deferred revenue, current portion		1,100,000		1,100,000
Percentage of royalty on net sales required to pay under the agreement	20.00%
Deferred revenue		7,200,000		7,200,000
Deferred revenue, noncurrent		$ 6,100,000		6,100,000
Celgene | License exercise fee
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of options for providing license program | option	1
Celgene | If Celgene exercises its option with respect to the option program
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Deferred revenue, current portion	$ 10,000,000
Celgene | If Celgene exercises its option with respect to the option program | Development milestone | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	23,000,000
Celgene | If Celgene exercises its option with respect to the option program | Regulatory milestones | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	247,500,000
Celgene | If Celgene exercises its rights with respect to either of the two additional license programs | Development milestone | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	23,000,000
Celgene | If Celgene exercises its rights with respect to either of the two additional license programs | Regulatory milestones | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	247,500,000
Celgene | If Celgene exercises its rights with respect to either of the two additional license programs | Sales-based milestones | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	$ 100,000,000
Celgene | If Celgene exercises its rights with respect to either of the two additional license programs | License exercise fee
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of options for providing license program | option	2
Deferred revenue, current portion	$ 30,000,000
Celgene | One of the other additional license programs | Sales-based milestones | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	50,000,000
Celgene | Research and development services deliverable
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
License, research and development revenue			11,000	2,000	19,000
Celgene | Supply deliverable
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
License, research and development revenue			$ 18,000	$ 10,000	$ 38,000
Celgene | CTP-730 Program | Non-refundable upfront payment arrangement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Deferred revenue, payment received	35,000,000
Celgene | CTP-730 Program | Development milestone
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable							$ 8,000,000
Celgene | CTP-730 Program | Regulatory milestones | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	247,500,000
Celgene | CTP-730 Program | Sales-based milestones | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	50,000,000
Celgene | CTP-730 Program | If Celgene exercises its option with respect to the option program | Development milestone
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	15,000,000
Celgene | Product collaborative arrangement | CTP-730 Program | Development milestone | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	$ 15,000,000

Collaborations - Jazz Pharmaceu

Collaborations - Jazz Pharmaceuticals - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Feb. 28, 2013	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
License, research and development revenue		$ 15,000	$ 71,000	$ 35,000	$ 127,000
Jazz Pharmaceuticals
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of royalty on net sales required to pay under the agreement	20.00%
Jazz Pharmaceuticals | Non-refundable upfront payment arrangement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Deferred revenue, payment received	$ 4,000,000
Jazz Pharmaceuticals | Regulatory milestones | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	35,000,000
Jazz Pharmaceuticals | Sales-based milestones | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	70,000,000
Jazz Pharmaceuticals | Development support services
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
License, research and development revenue		$ 15,000	$ 34,000	$ 22,000	$ 68,000
Jazz Pharmaceuticals | JZP 386
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	4,000,000
Jazz Pharmaceuticals | Co-promotion collaborative arrangement | Development milestone | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	$ 8,000,000

Collaborations - Avanir - Addit

Collaborations - Avanir - Additional Information (Detail) - Avanir Pharmaceuticals - USD ($)	1 Months Ended
	Feb. 29, 2012	Jun. 30, 2017
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable		$ 6,000,000
Non-refundable upfront payment arrangement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	$ 2,000,000
Regulatory and commercial launch milestone | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	37,000,000
Development milestone | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	21,500,000
Sales-based milestones | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	$ 125,000,000
Product collaborative arrangement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of royalty on net sales required to pay under the agreement	20.00%
Product collaborative arrangement | Licensed product
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	$ 43,000,000
Co-promotion collaborative arrangement | AVP-786 Program | Development milestone
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	3,000,000
US Food and Drug Administration | Product collaborative arrangement | AVP-786 Program | Development milestone
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	5,000,000
Ministry of Health, Labour and Welfare (MHLW) | Product collaborative arrangement | AVP-786 Program | Development milestone
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible payments receivable	$ 1,500,000

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	Jan. 01, 2017	Jun. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated forfeiture rate		7.00%
Total unrecognized compensation cost related to unvested options		$ 13.2
2014 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares issued under the plan (in shares)	892,679
Common stock available for future award grant (in shares)		1,709,515
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards expiration period		10 years
Vesting period		4 years
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to unvested options, weighted-average recognition period		2 years 8 months

Stock Based Compensation - Stoc

Stock Based Compensation - Stock-Based Compensation Expense Related to All Stock Based Awards Recognized in Statements of Operations and Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 1,573	$ 1,287	$ 3,216	$ 2,569
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	686	553	1,403	1,106
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 887	$ 734	$ 1,813	$ 1,463

Stock Based Compensation - Esti

Stock Based Compensation - Estimated Weighted-Average Assumptions of Options Granted (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected volatility	78.30%	78.12%	78.16%	78.31%
Expected term	6 years	6 years	6 years	6 years
Risk-free interest rate	2.02%	1.15%	2.07%	1.35%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value of Options (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of options granted, per option (dollars per share)	$ 9.29	$ 8.72	$ 7.66	$ 10.91
Aggregate grant date fair value of options vested during the period	$ 1,691	$ 1,352	$ 2,967	$ 2,384
Total cash received from exercises of stock options	317	63	1,456	239
Total intrinsic value of stock options exercised	$ 645	$ 131	$ 3,309	$ 628

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Detail) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2017USD ($)$ / sharesshares
Number of Option Shares
Number of options, Outstanding beginning balance (in shares) | shares	2,953,961
Number of options, Granted (in shares) | shares	1,059,300
Number of options, Exercised (in shares) | shares	(301,306)
Number of options, Forfeited or expired (in shares) | shares	(174,685)
Number of options, Outstanding ending balance (in shares) | shares	3,537,270
Number of options, Exercisable (in shares) | shares	1,747,298
Number of options, Vested and expected to vest (in shares) | shares	3,371,158
Weighted Average Exercise Price per Share
Weighted average exercise price per share, Outstanding at beginning of year (in dollars per share) | $ / shares	$ 10.49
Weighted average exercise price per share, Granted (in dollars per share) | $ / shares	11.23
Weighted average exercise price per share, Exercised (in dollars per share) | $ / shares	4.96
Weighted average exercise price per share, Forfeited or expired (in dollars per share) | $ / shares	12.17
Weighted average exercise price per share, Outstanding ending balance (in dollars per share) | $ / shares	11.10
Weighted average exercise price per share, Exercisable (in dollars per share) | $ / shares	9.57
Weighted average exercise price per share, Vested and expected to vest (in dollars per share) | $ / shares	$ 11.03
Weighted Average Remaining Contractual Term (In years)
Weighted average remaining contractual term, Outstanding	6 years 10 months 2 days
Weighted average remaining contractual term, Exercisable	5 years 4 months 27 days
Weighted average remaining contractual term, Vested and expected to vest	6 years 9 months 3 days
Aggregate Intrinsic Value
Aggregate intrinsic value, Outstanding | $	$ 12,333
Aggregate intrinsic value, Exercisable | $	8,527
Aggregate intrinsic value, Vested and expected to vest | $	$ 11,966

Earnings (Loss) Per Share - Com

Earnings (Loss) Per Share - Computation of Basic and Diluted Earnings (Loss) Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Numerator:
Net loss applicable to common stockholders - basic and diluted	$ (13,027)	$ (13,441)	$ (26,360)	$ (27,321)
Denominator:
Weighted average shares outstanding - basic (in shares)	22,579	22,217	22,479	22,208
Dilutive stock options (in shares)	0	0	0	0
Dilutive warrants (in shares)	0	0	0	0
Weighted average shares outstanding - diluted (in shares)	22,579	22,217	22,479	22,208
Net loss per share applicable to common stockholders - basic and diluted (in dollars per share)	$ (0.58)	$ (0.60)	$ (1.17)	$ (1.23)
Stock options
Anti-dilutive potential common stock equivalents excluded from the calculation of net loss per share:
Anti-dilutive potential common stock equivalents excluded from the calculation of net loss per share (in shares)	637	667	610	717
Warrants
Anti-dilutive potential common stock equivalents excluded from the calculation of net loss per share:
Anti-dilutive potential common stock equivalents excluded from the calculation of net loss per share (in shares)	132	71	132	71

Loan Payable and Warrant to P41

Loan Payable and Warrant to Purchase Common Stock - Additional Information (Details) - Loan Agreement	Jun. 01, 2021USD ($)	Jun. 08, 2017USD ($)$ / sharesshares	Jun. 01, 2021USD ($)Installment
Debt Instrument [Line Items]
Amount of warrants issued and exercisable (in shares) | shares		61,273
Warrant exercise price (in dollars per share) | $ / shares		$ 12.24
Warrant expiration term		5 years
Warrants total relative fair value		$ 500,000
Line of Credit | Secured Term Loan Facility
Debt Instrument [Line Items]
Secured term loan facility amount		30,000,000
Loan issuance costs incurred		$ 300,000
Secured term loan variable rate		8.55%
Interest rate during period		8.55%
Percent of assets Loan Agreement secured by		65.00%
Line of Credit | Secured Term Loan Facility | Minimum
Debt Instrument [Line Items]
Prepayment charge waived term		90 days
Line of Credit | Secured Term Loan Facility | Maximum
Debt Instrument [Line Items]
Prepayment charge waived term		6 months
Line of Credit | Secured Term Loan Facility | Prime rate
Debt Instrument [Line Items]
Basis spread on variable rate		4.50%
Line of Credit | Prepaid on or prior to June 1, 2018 | Secured Term Loan Facility
Debt Instrument [Line Items]
Prepayment of the principal percent		2.00%
Line of Credit | Prepaid during the period from June 1, 2018 to June 1, 2019 | Secured Term Loan Facility
Debt Instrument [Line Items]
Prepayment of the principal percent		1.00%
Line of Credit | Prepaid on and after June 1, 2019 | Secured Term Loan Facility
Debt Instrument [Line Items]
Prepayment of the principal percent		0.50%
Line of Credit | Scenario, forecast | Secured Term Loan Facility
Debt Instrument [Line Items]
Equal monthly installments | Installment			30
End of term charge	$ 1,500,000		$ 1,500,000
Potential end of term charge reduction	$ 700,000

Loan Payable and Warrant to P42

Loan Payable and Warrant to Purchase Common Stock - Loan Payable Future Minimum Payments (Details) - Line of Credit - Secured Term Loan Facility - Loan Agreement $ in Thousands	Jun. 30, 2017USD ($)
Long-term Debt, Fiscal Year Maturity [Abstract]
2,017	$ 0
2,018	0
2,019	11,209
2,020	12,216
2,021	6,575
Long-term debt, gross	$ 30,000

Loan Payable and Warrant to P43

Loan Payable and Warrant to Purchase Common Stock - Summary of Significant Assumptions Used in Warrant Fair Value Measurements (Details) - Warrants	Jun. 08, 2017
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Expected volatility	73.71%
Expected term (in years)	5 years
Risk-free interest rate	1.75%
Expected dividend yield	0.00%