Cara Therapeutics (CARA) 10-Q 5 May 16 2016 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2016	Apr. 29, 2016
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q1
Trading Symbol	CARA
Entity Registrant Name	Cara Therapeutics, Inc.
Entity Central Index Key	1,346,830
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		27,282,863

Condensed Balance Sheets

Condensed Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 7,922	$ 15,101
Marketable securities	88,322	91,640
Income tax receivable	529	384
Other receivables	128	80
Prepaid expenses	2,573	1,729
Total current assets	99,474	108,934
Property and equipment, net	1,070	1,263
Restricted cash	1,469	700
Total assets	102,013	110,897
Current liabilities:
Accounts payable and accrued expenses	6,089	5,268
Total current liabilities	6,089	5,268
Deferred lease obligation	$ 997	$ 585
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock; $0.001 par value; 5,000,000 shares authorized at March 31, 2016 and December 31, 2015, zero shares issued and outstanding at March 31, 2016 and December 31, 2015
Common stock; $0.001 par value; 100,000,000 shares authorized at March 31, 2016 and December 31, 2015, 27,282,863 shares and 27,254,863 shares issued and outstanding at March 31, 2016 and December 31, 2015, respectively	$ 27	$ 27
Additional paid-in capital	210,479	209,943
Accumulated deficit	(115,583)	(104,891)
Accumulated other comprehensive income (loss)	4	(35)
Total stockholders' equity	94,927	105,044
Total liabilities and stockholders' equity	$ 102,013	$ 110,897

Condensed Balance Sheets (Paren

Condensed Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 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	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	27,282,863	27,254,863
Common stock, shares outstanding	27,282,863	27,254,863

Condensed Statements of Compreh

Condensed Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenue:
Collaborative revenue		$ 489
Clinical compound revenue	$ 7
Total revenue	7	489
Operating expenses:
Research and development	8,546	3,385
General and administrative	2,447	1,822
Total operating expenses	10,993	5,207
Operating loss	(10,986)	(4,718)
Other income (expense), net	149	14
Loss before benefit from income taxes	(10,837)	(4,704)
Benefit from income taxes	145	15
Net loss	$ (10,692)	$ (4,689)
Net loss per share:
Basic and Diluted	$ (0.39)	$ (0.21)
Weighted average shares:
Basic and Diluted	27,259,589	22,808,479
Other comprehensive income (loss), net of tax of $0:
Unrealized gains on available-for-sale marketable securities	$ 39
Total comprehensive loss	$ (10,653)	$ (4,689)

Condensed Statements of Compre5

Condensed Statements of Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Other comprehensive income (loss), tax	$ 0	$ 0

Condensed Statements of Stockho

Condensed Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance, Value at Dec. 31, 2014	$ 51,662	$ 23	$ 131,840	$ (80,201)
Balance, Shares at Dec. 31, 2014		22,802,039
Stock-based compensation expense	445		445
Shares issued upon exercise of stock options, Value	6		6
Shares issued upon exercise of stock options, Shares		22,880
Net loss	(4,689)			(4,689)
Balance, Value at Mar. 31, 2015	47,424	$ 23	132,291	(84,890)
Balance, Shares at Mar. 31, 2015		22,824,919
Balance, Value at Dec. 31, 2015	105,044	$ 27	209,943	(104,891)	$ (35)
Balance, Shares at Dec. 31, 2015		27,254,863
Stock-based compensation expense	496		496
Shares issued upon exercise of stock options, Value	40		40
Shares issued upon exercise of stock options, Shares		28,000
Net loss	(10,692)			(10,692)
Other comprehensive income	39				39
Balance, Value at Mar. 31, 2016	$ 94,927	$ 27	$ 210,479	$ (115,583)	$ 4
Balance, Shares at Mar. 31, 2016		27,282,863

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Operating activities
Net loss	$ (10,692)	$ (4,689)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	496	445
Depreciation and amortization	730	193
Amortization/accretion of available-for-sale marketable securities	(67)
Deferred rent costs	(83)	(71)
Changes in operating assets and liabilities:
Income tax receivable	(145)	(15)
Other receivables	(48)
Prepaid expenses	(844)	(733)
Accounts payable and accrued expenses	820	118
Deferred revenue		(489)
Net cash used in operating activities	(9,833)	(5,241)
Investing activities
Proceeds from maturities of available-for-sale marketable securities	26,050
Purchase of available-for-sale marketable securities	(22,625)
Change in restricted cash	(769)
Cash paid for construction in progress	(34)
Purchases of property and equipment	(8)	(6)
Net cash provided by (used in) investing activities	2,614	(6)
Financing activities
Proceeds from the exercise of stock options	40	6
Net cash provided by financing activities	40	6
Net cash decrease for the period	(7,179)	(5,241)
Cash and cash equivalents at beginning of period	15,101	52,663
Cash and cash equivalents at end of period	7,922	$ 47,422
Noncash investing and financing activities
Tenant improvements paid by landlord	$ 495

Business

Business	3 Months Ended
	Mar. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business	1. Business Cara Therapeutics, Inc. (the “Company”, “we”, “our” or “us”) is a clinical-stage biopharmaceutical corporation formed on July 2, 2004. The Company is focused on developing and commercializing new chemical entities designed to alleviate pain and pruritus by selectively targeting peripheral kappa opioid receptors. The Company’s primary activities to date have been organizing and staffing the company, developing its product candidates, including conducting preclinical studies and clinical trials of CR845-based product candidates and raising capital. As of March 31, 2016, the Company has raised aggregate net proceeds of approximately $204,800 from several rounds of equity financing, including its initial public offering, which closed in February 2014 and its follow-on offering, which closed in August 2015, and the issuance of debt. In addition, the Company received approximately $32,500 under its license agreements for CR845, primarily with Maruishi Pharmaceutical Co. Ltd., or Maruishi, and Chong Kun Dang Pharmaceutical Corp., or CKD, and an earlier product candidate for which development efforts ceased in 2007. In connection with the license of rights to CR845 in Japan to Maruishi and as part of the payments described above, in April 2013, the Company received an upfront payment of $15,000, and in August 2014 and September 2015, the Company received additional milestone payments of $480 and $1,725 (net of contractual foreign currency exchange adjustments), respectively. In connection with the license of rights to CR845 in South Korea to CKD and as part of the payments described above, in 2012, the Company received aggregate upfront and milestone payments of $1,190, and in August 2015 and October 2015, the Company received additional milestone payments of $209 and $417 (net of South Korean withholding taxes), respectively. As of March 31, 2016, the Company had unrestricted cash and cash equivalents and marketable securities of $96,244 and an accumulated deficit of $115,583. The Company has incurred substantial net losses and negative cash flows from operating activities in nearly every fiscal period since inception and expects this trend to continue for the foreseeable future. The Company recognized net losses of $10,692 and $4,689 and had net cash used in operating activities of $9,833 and $5,241 for the three months ended March 31, 2016 and 2015, respectively. The Company expects that cash and cash equivalents and marketable securities as of March 31, 2016 will be sufficient to fund its operations beyond one year. The Company is subject to risks common to other life science companies including, but not limited to, uncertainty of product development and commercialization, lack of marketing and sales history, development by its competitors of new technological innovations, dependence on key personnel, market acceptance of products, product liability protection of proprietary technology, ability to raise additional financing, and compliance with Food and Drug Administration, or FDA, and other government regulations. If the Company does not successfully commercialize any of its product candidates, it will be unable to generate recurring product revenue or achieve profitability.

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	2. Basis of Presentation The unaudited interim condensed financial statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission, or the SEC. Accordingly, they do not include all information and disclosures necessary for a presentation of the Company’s financial position, results of operations and cash flows in conformity with generally accepted accounting principles in the United States of America, or GAAP. In the opinion of management, these unaudited interim financial statements reflect all adjustments, consisting primarily of normal recurring accruals, necessary for a fair presentation of results for the periods presented. The results of operations for interim periods are not necessarily indicative of the results for the full year. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted from this report, as is permitted by SEC rules and regulations; however, the Company believes that the disclosures are adequate to make the information presented not misleading. The condensed balance sheet data for the year ended December 31, 2015 were derived from audited financial statements, but do not include all disclosures required by GAAP. These unaudited interim condensed financial statements should be read in conjunction with the audited financial statements and accompanying notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2015. Use of Estimates The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, as of the date of the financial statements as well as the reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from the Company’s estimates and assumptions. Significant estimates include the fair value of marketable securities that are classified as level 2 of the fair value hierarchy, useful lives of fixed assets, the periods over which certain revenues will be recognized, including licensing and collaborative revenue recognized from non-refundable up-front and milestone payments, the determination of prepaid research and development, or R&D, clinical costs and accrued research projects, the amount of non-cash compensation costs related to share-based payments to employees and non-employees and the periods over which those costs are expensed and the likelihood of realization of deferred tax assets. Significant Accounting Policies There have been no material changes to the significant accounting policies previously disclosed in Note 2 to the Financial Statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2015. Recent Accounting Pronouncements In March 2016, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, No. 2016-08, Revenue from Contracts with Customers (Topic 606), Principal versus Agent Considerations (Reporting Revenue Gross versus Net) Revenue from Contracts with Customers (Topic 606) Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date. In March 2016, the FASB issued ASU No. 2016-09, Improvements to Employee Share-Based Payment Accounting Topic 718 Compensation – Stock Compensation In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606), Identifying Performance Obligations and Licensing , Revenue from Contracts with Customers (Topic 606) Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date.

Available-for-Sale Marketable S

Available-for-Sale Marketable Securities	3 Months Ended
	Mar. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Available-for-Sale Marketable Securities	3. Available-for-Sale Marketable Securities As of March 31, 2016 and December 31, 2015, the Company’s available-for-sale marketable securities consisted of money market mutual funds and debt securities issued by the U.S. government and government-sponsored entities and by investment grade institutions. The following tables summarize the Company’s available-for-sale marketable securities by major type of security as of March 31, 2016 and December 31, 2015: As of March 31, 2016 Gross Unrealized Estimated Fair Type of Security Amortized Cost Gains Losses Value Money market mutual funds $ 42,083 $ — $ — $ 42,083 U.S. Treasury securities 5,016 2 — 5,018 Other U.S. government agency obligations 6,766 1 — 6,767 Corporate bonds 13,278 4 — 13,282 Commercial paper 21,175 2 (5 ) 21,172 Total available-for-sale marketable securities $ 88,318 $ 9 $ (5 ) $ 88,322 As of December 31, 2015 Gross Unrealized Estimated Fair Type of Security Amortized Cost Gains Losses Value Money market mutual funds $ 42,017 $ — $ (31 ) $ 41,986 U.S. Treasury securities 2,528 — — 2,528 Other U.S. government agency obligations 13,492 4 — 13,496 Corporate bonds 14,194 — (6 ) 14,188 Commercial paper 19,444 1 (3 ) 19,442 Total available-for-sale marketable securities $ 91,675 $ 5 $ (40 ) $ 91,640 All available-for-sale marketable securities are classified in the Company’s Condensed Balance Sheets as Marketable securities. The Company classifies its marketable debt securities based on their contractual maturity dates. The marketable debt securities as of March 31, 2016 mature at various dates through March 2017. The fair values and amortized cost of marketable debt securities by contractual maturity were as follows. The table does not include money market funds that are classified as available-for-sale marketable securities. As of March 31, 2016 As of December 31, 2015 Contractual maturity Fair Value Amortized Cost Fair Value Amortized Cost Less than one year $ 46,239 $ 46,235 $ 49,653 $ 49,657 For the three months ended March 31, 2016, there were no sales of available-for-sale marketable securities. The following tables show the fair value of the Company’s available-for-sale marketable securities that have unrealized losses and that are deemed to be only temporarily impaired, aggregated by investment category and length of time that the individual investments have been in a continuous unrealized loss position. Less than 12 Months 12 Months or Greater Total As of March 31, 2016 Fair Value Gross Fair Value Gross Fair Value Gross Commercial paper $ 11,684 $ (5 ) $ — $ — $ 11,684 $ (5 ) Total $ 11,684 $ (5 ) $ — $ — $ 11,684 $ (5 ) Less than 12 Months 12 Months or Greater Total As of December 31, 2015 Fair Value Gross Fair Value Gross Fair Value Gross Money market mutual funds $ 30,985 $ (31 ) $ — $ — $ 30,985 $ (31 ) Corporate bonds 14,187 (6 ) — — 14,187 (6 ) Commercial paper 11,960 (3 ) — — 11,960 (3 ) Total $ 57,132 $ (40 ) $ — $ — $ 57,132 $ (40 ) As of March 31, 2016 and December 31, 2015, the Company held a total of 9 and 15 positions, respectively, that were in an unrealized loss position, none of which had been in an unrealized loss position for 12 months or greater. Based on the Company’s review of these securities, the Company believes that the cost basis of its available-for-sale marketable securities is recoverable and that, therefore, it had no other-than-temporary impairments on these securities as of March 31, 2016 and December 31, 2015. The Company does not intend to sell these debt securities and the Company believes it is not more likely than not that it will be required to sell these securities before the recovery of their amortized cost basis, which may be maturity.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	3 Months Ended
	Mar. 31, 2016
Equity [Abstract]
Accumulated Other Comprehensive Loss	4. Accumulated Other Comprehensive Loss The following table summarizes the changes in accumulated other comprehensive income (loss), or AOCI, net of tax, from unrealized gains (losses) on available-for-sale marketable securities, the Company’s only component of AOCI, for the three months ended March 31, 2016. For the three months ended March 31, 2015, all of the Company’s funds were held in money market savings and checking accounts that were classified as cash equivalents and not as available-for-sale marketable securities. For the three months ended March 31, 2016, there were no reclassifications from AOCI since there were no sales of available-for-sale marketable securities. Total Accumulated Balance, December 31, 2015 $ (35 ) Other comprehensive income before reclassifications 39 Amount reclassified from accumulated other comprehensive income — Net current period other comprehensive income 39 Balance, March 31, 2016 $ 4

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	5. Fair Value Measurements As of March 31, 2016 and December 31, 2015, the Company’s financial instruments consist of cash and cash equivalents, available-for-sale marketable securities, restricted cash, accounts payable and accrued liabilities. The fair values of cash and cash equivalents, restricted cash, accounts payable and accrued liabilities approximate their carrying values due to the short-term nature of these financial instruments. Marketable securities are reported on the Company’s Condensed Balance Sheets at their fair values, based upon pricing of securities with the same or similar investment characteristics as provided by third-party pricing services, as described below. Current accounting guidance defines fair value, establishes a framework for measuring fair value in accordance with ASC section 820, and requires certain disclosures about fair value measurements. The valuation techniques included in the guidance are based on observable and unobservable inputs. Observable inputs reflect readily obtainable data from independent sources, while unobservable inputs reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. The Company classifies its investments in a fair value hierarchy that is intended to increase consistency and comparability in fair value measurements and related disclosures. The fair value hierarchy is divided into three levels based on the source of inputs as follows: • Level 1 – Observable inputs – quoted prices in active markets for identical assets and liabilities. • Level 2 – Observable inputs other than the quoted prices in active markets for identical assets and liabilities – such as quoted prices for similar instruments, quoted prices for identical or similar instruments in inactive markets, or other inputs that are observable or can be corroborated by observable market data. • Level 3 – Unobservable inputs – includes amounts derived from valuation models where one or more significant inputs are unobservable and require the Company to develop relevant assumptions. Valuation Techniques - Level 2 Inputs The Company estimates the fair values of its financial instruments categorized as level 2 in the fair value hierarchy, including U.S. Treasury securities, other U.S. government agency obligations, corporate bonds and commercial paper by taking into consideration valuations obtained from third-party pricing services. The pricing services use industry standard valuation models, including both income- and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities, benchmark yields, issuer credit spreads, benchmark securities, and other observable inputs. The Company obtains a single price for each financial instrument and does not adjust the prices obtained from the pricing service. The Company validates the prices provided by its third party pricing services by reviewing their pricing methods, obtaining market values from other pricing sources and comparing them to the share prices presented by the pricing service. After completing its validation procedures, the Company did not adjust or override any fair value measurements provided by its pricing services as of March 31, 2016 or December 31, 2015. The following tables summarize the Company’s financial assets measured at fair value on a recurring basis as of March 31, 2016 and December 31, 2015. Fair value measurement as of March 31, 2016 Financial assets Total Quoted prices in (Level 1) Significant other (Level 2) Significant (Level 3) Type of Instrument Cash and cash equivalents: Money market mutual funds, savings account and checking account $ 7,922 $ 7,922 $ — $ — Available-for-sale marketable securities: Money market mutual funds 42,083 — 42,083 — U.S. Treasury securities 5,018 — 5,018 — Other U.S. government agency obligations 6,767 — 6,767 — Corporate bonds 13,282 — 13,282 — Commercial paper 21,172 — 21,172 — Restricted cash: Commercial money market account 1,469 1,469 — — Total financial assets $ 97,713 $ 9,391 $ 88,322 $ — Fair value measurement as of December 31, 2015: Financial assets Total Quoted prices in (Level 1) Significant other (Level 2) Significant (Level 3) Type of Instrument Cash and cash equivalents: Money market mutual funds, savings account and checking account $ 15,101 $ 15,101 $ — $ — Available-for-sale marketable securities: Money market mutual funds 41,986 41,986 — U.S. Treasury securities 2,528 2,528 — Other U.S. government agency obligations 13,496 13,496 — Corporate bonds 14,188 14,188 — Commercial paper 19,442 19,442 — Restricted cash: Bank Certificate of Deposit 700 700 — — Total financial assets $ 107,441 $ 15,801 $ 91,640 $ — There were no purchases, sales or maturities of Level 3 financial assets and no unrealized gains or losses related to Level 3 available-for-sale marketable securities for the three months ended March 31, 2016. There were no transfers of financial assets between Levels 1, 2, or 3 classifications during the three months ended March 31, 2016.

Restricted Cash

Restricted Cash	3 Months Ended
	Mar. 31, 2016
Receivables [Abstract]
Restricted Cash	6. Restricted Cash The Company is required to maintain stand-by letters of credit as security deposits under each of the Shelton Lease and the Stamford Lease (refer to Note 12, Commitments and Contingencies The restricted cash balance for the Shelton Lease remains at $700 through the end of the lease term in 2017. For the Stamford Lease, the letter of credit balance remains at $769 for the first three years following commencement of the Stamford Lease and may, upon request from the Company, thereafter be reduced to $408 through the end of the lease term in 2023. The reduction in the balance of the Letter of Credit for the Stamford Lease is contingent upon the Company not being in default of any provisions of that lease prior to request for the reduction. As of March 31, 2016 and December 31, 2015, the Company had $1,469 and $700 of restricted cash, respectively, in long-term assets.

Prepaid Expenses

Prepaid Expenses	3 Months Ended
	Mar. 31, 2016
Text Block [Abstract]
Prepaid Expenses	7. Prepaid expenses As of March 31, 2016, prepaid expenses were $2,573, consisting of $1,810 of prepaid R&D clinical costs, $671 of prepaid insurance and $92 of other prepaid costs. As of December 31, 2015, prepaid expenses were $1,729 consisting of $1,500 of prepaid R&D clinical costs, $98 of prepaid insurance, $96 of prepaid rent, and $35 of other prepaid costs.

Accounts Payable and Accrued Ex

Accounts Payable and Accrued Expenses	3 Months Ended
	Mar. 31, 2016
Payables and Accruals [Abstract]
Accounts Payable and Accrued Expenses	8. Accounts Payable and Accrued Expenses Accounts payable and accrued expenses consist of the following: March 31, 2016 December 31, 2015 Accounts payable $ 2,348 $ 1,965 Accrued research projects 2,495 1,542 Accrued professional fees 398 371 Accrued compensation and benefits 646 1,204 Accrued other 202 186 Total $ 6,089 $ 5,268

Net Loss Per Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Net Loss Per Share	9. Net Loss Per Share The Company computes basic net income (loss) per share by dividing net income (loss) by the weighted average number of shares of common stock outstanding. Diluted net income per share includes the potential dilutive effect of common stock equivalents as if such securities were exercised during the period, when the effect is dilutive. Common stock equivalents may include outstanding stock options, which are included using the treasury stock method when dilutive. For the three months ended March 31, 2016 and 2015, the Company excluded the effects of potentially dilutive shares that were outstanding during those respective periods from the denominator as their inclusion would be anti-dilutive due to the Company’s net losses during those periods. The denominators used in the net loss per share computations are as follows: Three Months Ended March 31, 2016 2015 Basic: Weighted average common shares outstanding 27,259,589 22,808,479 Diluted: Weighted average common shares outstanding -Basic 27,259,589 22,808,479 Common stock options* — — Denominator for diluted net loss per share 27,259,589 22,808,479 * No amounts were considered as their effects would be anti-dilutive. Basic and diluted net loss per share are computed as follows: Three Months Ended March 31, 2016 2015 Net loss $ (10,692 ) $ (4,689 ) Weighted-average common shares outstanding: Basic and Diluted 27,259,589 22,808,479 Net loss per share, Basic and Diluted $ (0.39 ) $ (0.21 ) At the end of the respective periods presented above, 2,214,492 and 1,294,480 stock options were outstanding, which could potentially dilute basic earnings per share in the future, but were not included in the computation of diluted net loss per share because to do so would have been anti-dilutive.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	10. Stock-Based Compensation 2014 Equity Incentive Plan The Company’s 2014 Equity Incentive Plan, or the 2014 Plan, is administered by the Company’s Board of Directors or a duly authorized committee thereof, referred to as the Plan administrator. The 2014 Plan provides for the grant of incentive stock options, non-statutory stock options, restricted stock awards, restricted stock unit awards, stock appreciation rights, performance stock awards and other forms of equity compensation, collectively, Stock Awards. Additionally, the 2014 Plan provides for the grant of performance cash awards. Incentive stock options may be granted only to employees. All other awards may be granted to employees, including officers, non-employee directors, and consultants. No incentive stock options may be granted under the 2014 Plan after the tenth anniversary of the effective date of the 2014 Plan. Stock Awards granted under the 2014 Plan vest at the rate specified by the Plan administrator, which, to date, has generally been 25% on the first anniversary of the date of grant and the balance ratably over the next 36 months. Grants of Stock Awards made during the three months ended March 31, 2016 to employees, who had previously been granted Stock Awards, vest monthly from the grant date. The Plan administrator determines the term of Stock Awards granted under the 2014 Plan up to a maximum of ten years. The aggregate number of shares of the Company’s common stock reserved for issuance under the 2014 Plan will automatically increase on January 1 of each year, beginning on January 1, 2015 and continuing through and including January 1, 2024, by 3% of the total number of shares of the Company’s capital stock outstanding on December 31 of the preceding calendar year, or a lesser number of shares determined by the Company’s Board of Directors. On January 1, 2016, the aggregate number of shares of common stock that may be issued pursuant to stock awards under the 2014 Plan automatically increased from 2,284,061 to 3,101,707. The maximum number of shares that may be issued pursuant to the exercise of incentive stock options under the 2014 Plan is 30,000,000 shares. Under the 2014 Plan, the Company granted 610,000 and 295,000 stock options during the three months ended March 31, 2016 and 2015, respectively. The fair values of stock options granted during the three months ended March 31, 2016 and 2015 were estimated as of the dates of grant using the Black-Scholes option pricing model with the following assumptions: Three Months Ended March 31, 2016 2015 Risk-free interest rate 1.40% - 1.59% 1.43% - 1.70% Expected volatility 67.8% - 69.7% 65% - 67% Expected dividend yield 0% 0% Expected life of employee options (in years) 6.25 6.25 Expected life of nonemployee options (in years) 10 10 The weighted average grant date fair value of options granted to employees during the three months ended March 31, 2016 and 2015 was $3.85 and $6.23, respectively. The weighted average fair value of outstanding vested options that had been granted to nonemployee consultants as re-measured during the three months ended March 31, 2016 and 2015, in accordance with ASC 505-50, was $3.82 and $7.22, respectively. During the three months ended March 31, 2016 and 2015, the Company recognized compensation expense relating to stock options, as follows: Three Months Ended March 31, 2016 2015 Research and development $ 189 $ 198 General and administrative 307 247 Total stock option expense $ 496 $ 445 A summary of stock option award activity related to employees, non-employee members of the Company’s Board of Directors and non-employee consultants as of and for the three months ended March 31, 2016 is presented below: Number of Weighted Outstanding, December 31, 2015 1,658,408 $ 10.27 Granted 610,000 6.08 Exercised (28,000 ) 1.41 Forfeited (25,000 ) 15.49 Expired (916 ) 11.00 Outstanding, March 31, 2016 2,214,492 $ 9.17 Options exercisable, March 31, 2016 614,109 $ 8.64

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	11. Income Taxes For the three months ended March 31, 2016 and 2015, pre-tax losses were $10,837 and $4,704, respectively. The Company recognized a full tax valuation allowance against net deferred tax assets at March 31, 2016 and December 31, 2015. The benefit from income taxes of $145 and $15 for the three months ended March 31, 2016 and 2015, respectively, relates to state R&D tax credits exchanged for cash pursuant to the Connecticut R&D Tax Credit Exchange Program, which permits qualified small businesses engaged in R&D activities within Connecticut to exchange their unused R&D tax credits for a cash amount equal to 65% of the value of the exchanged credits.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	12. Commitments and Contingencies Contractual obligations and commitments as of March 31, 2016 were as follows: Payment Due for the Year Ending December 31, 2016 2017 2018 2019 2020 Thereafter Total Shelton operating lease (1) $ 686 $ 740 $ — $ — $ — $ — $ 1,426 Stamford operating lease (2) 192 875 1,093 1,217 1,241 3,650 8,268 $ 878 $ 1,615 $ 1,093 $ 1,217 $ 1,241 $ 3,650 $ 9,694 (1) The Company leases its operating facility located in Shelton, Connecticut (See Note 21 of Notes to Financial Statements, Commitments and Contingencies (2) In December 2015, the Company signed a lease for office space in Stamford, Connecticut for the purpose of relocating its operating facility as of May, 2016 (See Note 21 of Notes to Financial Statements, Commitments and Contingencies

Basis of Presentation (Policies

Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, as of the date of the financial statements as well as the reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from the Company’s estimates and assumptions. Significant estimates include the fair value of marketable securities that are classified as level 2 of the fair value hierarchy, useful lives of fixed assets, the periods over which certain revenues will be recognized, including licensing and collaborative revenue recognized from non-refundable up-front and milestone payments, the determination of prepaid research and development, or R&D, clinical costs and accrued research projects, the amount of non-cash compensation costs related to share-based payments to employees and non-employees and the periods over which those costs are expensed and the likelihood of realization of deferred tax assets.
Significant Accounting Policies	Significant Accounting Policies There have been no material changes to the significant accounting policies previously disclosed in Note 2 to the Financial Statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2015.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In March 2016, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, No. 2016-08, Revenue from Contracts with Customers (Topic 606), Principal versus Agent Considerations (Reporting Revenue Gross versus Net) Revenue from Contracts with Customers (Topic 606) Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date. In March 2016, the FASB issued ASU No. 2016-09, Improvements to Employee Share-Based Payment Accounting Topic 718 Compensation – Stock Compensation In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606), Identifying Performance Obligations and Licensing , Revenue from Contracts with Customers (Topic 606) Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date.

Available-for-Sale Marketable21

Available-for-Sale Marketable Securities (Tables)	3 Months Ended
	Mar. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Summary of Available-for-Sale Marketable Securities by Major Type of Security	The following tables summarize the Company’s available-for-sale marketable securities by major type of security as of March 31, 2016 and December 31, 2015: As of March 31, 2016 Gross Unrealized Estimated Fair Type of Security Amortized Cost Gains Losses Value Money market mutual funds $ 42,083 $ — $ — $ 42,083 U.S. Treasury securities 5,016 2 — 5,018 Other U.S. government agency obligations 6,766 1 — 6,767 Corporate bonds 13,278 4 — 13,282 Commercial paper 21,175 2 (5 ) 21,172 Total available-for-sale marketable securities $ 88,318 $ 9 $ (5 ) $ 88,322 As of December 31, 2015 Gross Unrealized Estimated Fair Type of Security Amortized Cost Gains Losses Value Money market mutual funds $ 42,017 $ — $ (31 ) $ 41,986 U.S. Treasury securities 2,528 — — 2,528 Other U.S. government agency obligations 13,492 4 — 13,496 Corporate bonds 14,194 — (6 ) 14,188 Commercial paper 19,444 1 (3 ) 19,442 Total available-for-sale marketable securities $ 91,675 $ 5 $ (40 ) $ 91,640
Schedule of Fair Values and Amortized Cost of Marketable Debt Securities by Contractual Maturity	The Company classifies its marketable debt securities based on their contractual maturity dates. The marketable debt securities as of March 31, 2016 mature at various dates through March 2017. The fair values and amortized cost of marketable debt securities by contractual maturity were as follows. The table does not include money market funds that are classified as available-for-sale marketable securities. As of March 31, 2016 As of December 31, 2015 Contractual maturity Fair Value Amortized Cost Fair Value Amortized Cost Less than one year $ 46,239 $ 46,235 $ 49,653 $ 49,657
Schedule of Fair Values and Continuous Unrealized Loss Positions of Available-for-Sale Marketable Securities	The following tables show the fair value of the Company’s available-for-sale marketable securities that have unrealized losses and that are deemed to be only temporarily impaired, aggregated by investment category and length of time that the individual investments have been in a continuous unrealized loss position. Less than 12 Months 12 Months or Greater Total As of March 31, 2016 Fair Value Gross Fair Value Gross Fair Value Gross Commercial paper $ 11,684 $ (5 ) $ — $ — $ 11,684 $ (5 ) Total $ 11,684 $ (5 ) $ — $ — $ 11,684 $ (5 ) Less than 12 Months 12 Months or Greater Total As of December 31, 2015 Fair Value Gross Fair Value Gross Fair Value Gross Money market mutual funds $ 30,985 $ (31 ) $ — $ — $ 30,985 $ (31 ) Corporate bonds 14,187 (6 ) — — 14,187 (6 ) Commercial paper 11,960 (3 ) — — 11,960 (3 ) Total $ 57,132 $ (40 ) $ — $ — $ 57,132 $ (40 )

Accumulated Other Comprehensi22

Accumulated Other Comprehensive Loss (Tables)	3 Months Ended
	Mar. 31, 2016
Equity [Abstract]
Summary of Changes in Accumulated Other Comprehensive Income (Loss), Net of Tax, from Unrealized Gains (Losses) on Available-for-Sale Marketable Securities	The following table summarizes the changes in accumulated other comprehensive income (loss), or AOCI, net of tax, from unrealized gains (losses) on available-for-sale marketable securities, the Company’s only component of AOCI, for the three months ended March 31, 2016. For the three months ended March 31, 2015, all of the Company’s funds were held in money market savings and checking accounts that were classified as cash equivalents and not as available-for-sale marketable securities. For the three months ended March 31, 2016, there were no reclassifications from AOCI since there were no sales of available-for-sale marketable securities. Total Accumulated Balance, December 31, 2015 $ (35 ) Other comprehensive income before reclassifications 39 Amount reclassified from accumulated other comprehensive income — Net current period other comprehensive income 39 Balance, March 31, 2016 $ 4

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Summary of Financial Assets Measured at Fair Value on Recurring Basis	The following tables summarize the Company’s financial assets measured at fair value on a recurring basis as of March 31, 2016 and December 31, 2015. Fair value measurement as of March 31, 2016 Financial assets Total Quoted prices in (Level 1) Significant other (Level 2) Significant (Level 3) Type of Instrument Cash and cash equivalents: Money market mutual funds, savings account and checking account $ 7,922 $ 7,922 $ — $ — Available-for-sale marketable securities: Money market mutual funds 42,083 — 42,083 — U.S. Treasury securities 5,018 — 5,018 — Other U.S. government agency obligations 6,767 — 6,767 — Corporate bonds 13,282 — 13,282 — Commercial paper 21,172 — 21,172 — Restricted cash: Commercial money market account 1,469 1,469 — — Total financial assets $ 97,713 $ 9,391 $ 88,322 $ — Fair value measurement as of December 31, 2015: Financial assets Total Quoted prices in (Level 1) Significant other (Level 2) Significant (Level 3) Type of Instrument Cash and cash equivalents: Money market mutual funds, savings account and checking account $ 15,101 $ 15,101 $ — $ — Available-for-sale marketable securities: Money market mutual funds 41,986 41,986 — U.S. Treasury securities 2,528 2,528 — Other U.S. government agency obligations 13,496 13,496 — Corporate bonds 14,188 14,188 — Commercial paper 19,442 19,442 — Restricted cash: Bank Certificate of Deposit 700 700 — — Total financial assets $ 107,441 $ 15,801 $ 91,640 $ —

Accounts Payable and Accrued 24

Accounts Payable and Accrued Expenses (Tables)	3 Months Ended
	Mar. 31, 2016
Payables and Accruals [Abstract]
Schedule of Accounts Payable and Accrued Expenses	Accounts payable and accrued expenses consist of the following: March 31, 2016 December 31, 2015 Accounts payable $ 2,348 $ 1,965 Accrued research projects 2,495 1,542 Accrued professional fees 398 371 Accrued compensation and benefits 646 1,204 Accrued other 202 186 Total $ 6,089 $ 5,268

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Computation of Denominators Used in Net Loss per Share	The denominators used in the net loss per share computations are as follows: Three Months Ended March 31, 2016 2015 Basic: Weighted average common shares outstanding 27,259,589 22,808,479 Diluted: Weighted average common shares outstanding -Basic 27,259,589 22,808,479 Common stock options* — — Denominator for diluted net loss per share 27,259,589 22,808,479 * No amounts were considered as their effects would be anti-dilutive.
Computation of Basic and Diluted Net Loss per Share	Basic and diluted net loss per share are computed as follows: Three Months Ended March 31, 2016 2015 Net loss $ (10,692 ) $ (4,689 ) Weighted-average common shares outstanding: Basic and Diluted 27,259,589 22,808,479 Net loss per share, Basic and Diluted $ (0.39 ) $ (0.21 )

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Assumptions Used in Black-Scholes Option Pricing Model	The fair values of stock options granted during the three months ended March 31, 2016 and 2015 were estimated as of the dates of grant using the Black-Scholes option pricing model with the following assumptions: Three Months Ended March 31, 2016 2015 Risk-free interest rate 1.40% - 1.59% 1.43% - 1.70% Expected volatility 67.8% - 69.7% 65% - 67% Expected dividend yield 0% 0% Expected life of employee options (in years) 6.25 6.25 Expected life of nonemployee options (in years) 10 10
Summary of Compensation Expense Relating to Stock Options	During the three months ended March 31, 2016 and 2015, the Company recognized compensation expense relating to stock options, as follows: Three Months Ended March 31, 2016 2015 Research and development $ 189 $ 198 General and administrative 307 247 Total stock option expense $ 496 $ 445
Summary of Stock Option Award Activity	A summary of stock option award activity related to employees, non-employee members of the Company’s Board of Directors and non-employee consultants as of and for the three months ended March 31, 2016 is presented below: Number of Weighted Outstanding, December 31, 2015 1,658,408 $ 10.27 Granted 610,000 6.08 Exercised (28,000 ) 1.41 Forfeited (25,000 ) 15.49 Expired (916 ) 11.00 Outstanding, March 31, 2016 2,214,492 $ 9.17 Options exercisable, March 31, 2016 614,109 $ 8.64

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Schedule of Contractual Obligations and Commitments	Contractual obligations and commitments as of March 31, 2016 were as follows: Payment Due for the Year Ending December 31, 2016 2017 2018 2019 2020 Thereafter Total Shelton operating lease (1) $ 686 $ 740 $ — $ — $ — $ — $ 1,426 Stamford operating lease (2) 192 875 1,093 1,217 1,241 3,650 8,268 $ 878 $ 1,615 $ 1,093 $ 1,217 $ 1,241 $ 3,650 $ 9,694 (1) The Company leases its operating facility located in Shelton, Connecticut (See Note 21 of Notes to Financial Statements, Commitments and Contingencies (2) In December 2015, the Company signed a lease for office space in Stamford, Connecticut for the purpose of relocating its operating facility as of May, 2016 (See Note 21 of Notes to Financial Statements, Commitments and Contingencies

Business - Additional Informati

Business - Additional Information (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Oct. 31, 2015	Sep. 30, 2015	Aug. 31, 2015	Aug. 31, 2014	Apr. 30, 2013	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2012	Dec. 31, 2015
Nature Of Business [Line Items]
Date of formation							Jul. 2, 2004
Proceeds from equity and debt financing	$ 204,800
Upfront and milestone payments received in connection with license agreements	32,500
Unrestricted cash and cash equivalents and marketable securities	96,244						$ 96,244
Accumulated deficit	$ 115,583						115,583			$ 104,891
Net loss							10,692	$ 4,689
Net cash used in operating activities							$ 9,833	$ 5,241
Minimum [Member]
Nature Of Business [Line Items]
Expected period to fund operations							1 year
Maruishi Pharmaceutical Co., Ltd. [Member]
Nature Of Business [Line Items]
Upfront license fee received						$ 15,000
Milestone payment received			$ 1,725		$ 480
Chong Kun Dang Pharmaceutical Corporation [Member]
Nature Of Business [Line Items]
Milestone payment received		$ 417		$ 209
Upfront and milestone payments related to license agreement									$ 1,190

Available-for-Sale Marketable29

Available-for-Sale Marketable Securities - Summary of Available-for-Sale Marketable Securities by Major Type of Security (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 88,318	$ 91,675
Gross Unrealized Gains	9	5
Gross Unrealized Losses	(5)	(40)
Estimated Fair Value	88,322	91,640
Money Market Mutual Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	42,083	42,017
Gross Unrealized Losses		(31)
Estimated Fair Value	42,083	41,986
U.S. Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	5,016	2,528
Gross Unrealized Gains	2
Estimated Fair Value	5,018	2,528
Other U.S. Government Agency Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	6,766	13,492
Gross Unrealized Gains	1	4
Estimated Fair Value	6,767	13,496
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	13,278	14,194
Gross Unrealized Gains	4
Gross Unrealized Losses		(6)
Estimated Fair Value	13,282	14,188
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	21,175	19,444
Gross Unrealized Gains	2	1
Gross Unrealized Losses	(5)	(3)
Estimated Fair Value	$ 21,172	$ 19,442

Available-for-Sale Marketable30

Available-for-Sale Marketable Securities - Schedule of Fair Values and Amortized Cost of Marketable Debt Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Fair value of marketable debt securities, contractual maturity, Less than one year	$ 46,239	$ 49,653
Amortized Cost of marketable debt securities, contractual maturity, Less than one year	$ 46,235	$ 49,657

Available-for-Sale Marketable31

Available-for-Sale Marketable Securities - Schedule of Fair Values and Continuous Unrealized Loss Positions of Available-for-Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Fair Value	$ 11,684	$ 57,132
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Gross Unrealized Losses	(5)	(40)
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Fair Value	0	0
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Gross Unrealized Losses	0	0
Available-for-sale marketable securities, continuous unrealized loss position, Fair Value	11,684	57,132
Available-for-sale marketable securities, continuous unrealized loss position, Gross Unrealized Losses	(5)	(40)
Money Market Mutual Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Fair Value		30,985
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Gross Unrealized Losses		(31)
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Fair Value		0
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Gross Unrealized Losses		0
Available-for-sale marketable securities, continuous unrealized loss position, Fair Value		30,985
Available-for-sale marketable securities, continuous unrealized loss position, Gross Unrealized Losses		(31)
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Fair Value		14,187
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Gross Unrealized Losses		(6)
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Fair Value		0
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Gross Unrealized Losses		0
Available-for-sale marketable securities, continuous unrealized loss position, Fair Value		14,187
Available-for-sale marketable securities, continuous unrealized loss position, Gross Unrealized Losses		(6)
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Fair Value	11,684	11,960
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Gross Unrealized Losses	(5)	(3)
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Fair Value	0	0
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Gross Unrealized Losses	0	0
Available-for-sale marketable securities, continuous unrealized loss position, Fair Value	11,684	11,960
Available-for-sale marketable securities, continuous unrealized loss position, Gross Unrealized Losses	$ (5)	$ (3)

Available-for-Sale Marketable32

Available-for-Sale Marketable Securities - Additional Information (Detail) - Position	Mar. 31, 2016	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Number of available-for-sale marketable securities in unrealized loss positions	9	15

Accumulated Other Comprehensi33

Accumulated Other Comprehensive Loss - Summary of Changes in Accumulated Other Comprehensive Income (Loss), Net of Tax, from Unrealized Gains (Losses) on Available-for-Sale Marketable Securities (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2016USD ($)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Total Accumulated Other Comprehensive Income (Loss), Beginning Balance	$ (35)
Other comprehensive income before reclassifications	39
Amount reclassified from accumulated other comprehensive income	0
Net current period other comprehensive income	39
Total Accumulated Other Comprehensive Income (Loss), Ending Balance	$ 4

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financial assets
Available-for-sale marketable securities	$ 88,322	$ 91,640
Corporate Bonds [Member]
Financial assets
Available-for-sale marketable securities	13,282	14,188
Recurring [Member]
Financial assets
Total financial assets	97,713	107,441
Recurring [Member] | Corporate Bonds [Member]
Financial assets
Available-for-sale marketable securities	13,282	14,188
Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets
Total financial assets	9,391	15,801
Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets
Total financial assets	88,322	91,640
Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Corporate Bonds [Member]
Financial assets
Available-for-sale marketable securities	13,282	14,188
Recurring [Member] | Money Market Mutual Funds [Member]
Financial assets
Cash and cash equivalents	7,922	15,101
Available-for-sale marketable securities	42,083	41,986
Recurring [Member] | Money Market Mutual Funds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets
Cash and cash equivalents	7,922	15,101
Recurring [Member] | Money Market Mutual Funds [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets
Available-for-sale marketable securities	42,083	41,986
Recurring [Member] | Commercial Paper [Member]
Financial assets
Available-for-sale marketable securities	21,172	19,442
Recurring [Member] | Commercial Paper [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets
Available-for-sale marketable securities	21,172	19,442
Recurring [Member] | Other U.S. Government Agency Obligations [Member]
Financial assets
Available-for-sale marketable securities	6,767	13,496
Recurring [Member] | Other U.S. Government Agency Obligations [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets
Available-for-sale marketable securities	6,767	13,496
Recurring [Member] | U.S. Treasury Securities [Member]
Financial assets
Available-for-sale marketable securities	5,018	2,528
Recurring [Member] | U.S. Treasury Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets
Available-for-sale marketable securities	5,018	2,528
Recurring [Member] | Bank Certificate of Deposit [Member]
Financial assets
Restricted cash		700
Recurring [Member] | Bank Certificate of Deposit [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets
Restricted cash		$ 700
Recurring [Member] | Commercial Money Market Account [Member]
Financial assets
Restricted cash	1,469
Recurring [Member] | Commercial Money Market Account [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets
Restricted cash	$ 1,469

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2016USD ($)Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Purchases of financial assets	$ 0
Sales of financial assets	0
Maturities of financial assets	$ 0
Transfers of financial assets between Levels 1, 2, or 3 classifications | Securities	0
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unrealized gains	$ 0
Unrealized losses	$ 0

Restricted Cash - Additional In

Restricted Cash - Additional Information (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash balance	$ 1,469	$ 700
Shelton Lease [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash balance	$ 700
Lease term	2,017
Stamford Lease [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Lease term	2,023
Letter of credit, remaining amount	$ 769
Letter of credit, remaining amount after three years	$ 408

Prepaid Expenses - Additional I

Prepaid Expenses - Additional Information (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid expenses	$ 2,573	$ 1,729
Prepaid insurance	671	98
Prepaid R&D clinical costs	1,810	1,500
Other prepaid costs	$ 92	35
Prepaid rent		$ 96

Accounts Payable and Accrued 38

Accounts Payable and Accrued Expenses - Schedule of Accounts Payable and Accrued Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Payables and Accruals [Abstract]
Accounts payable	$ 2,348	$ 1,965
Accrued research projects	2,495	1,542
Accrued professional fees	398	371
Accrued compensation and benefits	646	1,204
Accrued other	202	186
Total	$ 6,089	$ 5,268

Net Loss Per Share - Computatio

Net Loss Per Share - Computation of Denominators Used in Net Loss per Share (Detail) - shares	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Basic:
Weighted average common shares outstanding	27,259,589	22,808,479
Diluted:
Weighted average common shares outstanding -Basic	27,259,589	22,808,479
Common stock options	0	0
Denominator for diluted net loss per share	27,259,589	22,808,479

Net Loss Per Share - Computat40

Net Loss Per Share - Computation of Basic and Diluted Net Loss per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Earnings Per Share [Abstract]
Net loss	$ (10,692)	$ (4,689)
Weighted-average common shares outstanding:
Basic and Diluted	27,259,589	22,808,479
Net loss per share, Basic and Diluted	$ (0.39)	$ (0.21)

Net Loss Per Share - Additional

Net Loss Per Share - Additional Information (Detail) - shares	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive common stock equivalents	2,214,492	1,294,480

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - $ / shares	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Jan. 01, 2016	Dec. 31, 2015
Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of options granted	$ 3.85	$ 6.23
Nonemployee Consultants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair values of outstanding vested options	$ 3.82	$ 7.22
2014 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options that may be granted after the tenth anniversary of the 2014 Plan	0
Annual increases in number of shares reserved for issuance as a percentage of shares of capital stock outstanding through January 1, 2024	3.00%
Share-based compensation arrangement by share-based payment award, number of shares authorized			3,101,707	2,284,061
Options granted	610,000	295,000
2014 Equity Incentive Plan [Member] | Share-Based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of vested shares on first anniversary of grant date	25.00%
2014 Equity Incentive Plan [Member] | Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted	36 months
2014 Equity Incentive Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of awards granted	10 years
2014 Equity Incentive Plan [Member] | Incentive Stock Options [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized	30,000,000

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Assumptions Used in Black-Scholes Option Pricing Model (Detail)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	1.40%	1.43%
Risk-free interest rate, maximum	1.59%	1.70%
Expected volatility, minimum	67.80%	65.00%
Expected volatility, maximum	69.70%	67.00%
Expected dividend yield	0.00%	0.00%
Employee Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life of options (in years)	6 years 3 months	6 years 3 months
Nonemployee Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life of options (in years)	10 years	10 years

Stock-Based Compensation - Su44

Stock-Based Compensation - Summary of Compensation Expense Relating to Stock Options (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock option expense	$ 496	$ 445
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock option expense	189	198
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock option expense	$ 307	$ 247

Stock-Based Compensation - Su45

Stock-Based Compensation - Summary of Stock Option Award Activity (Detail) - 2014 Equity Incentive Plan [Member] - $ / shares	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Outstanding, at December 31, 2015	1,658,408
Number of Shares, Granted	610,000	295,000
Number of Shares, Exercised	(28,000)
Number of shares, Forfeited	(25,000)
Number of shares, Expired	(916)
Number of Shares, Outstanding, March 31, 2016	2,214,492
Number of Shares, Options exercisable, March 31, 2016	614,109
Weighted-Average Exercise Price, Outstanding, at December 31, 2015	$ 10.27
Weighted-Average Exercise Price, Granted	6.08
Weighted-Average Exercise Price, Exercised	1.41
Weighted-Average Exercise Price, Forfeited	15.49
Weighted-Average Exercise Price, Expired	11
Weighted Average Exercise Price, Outstanding, March 31, 2016	9.17
Weighted Average Exercise Price, Options exercisable, March 31, 2016	$ 8.64

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Pre-tax losses	$ 10,837	$ 4,704
Benefit from income taxes	$ 145	$ 15
Percentage of annual research and development credit for cash	65.00%

Commitments and Contingencies -

Commitments and Contingencies - Schedule of Contractual Obligations and Commitments (Detail) $ in Thousands	Mar. 31, 2016USD ($)
Operating Leased Assets [Line Items]
2,016	$ 878
2,017	1,615
2,018	1,093
2,019	1,217
2,020	1,241
Thereafter	3,650
Total	9,694
Shelton Operating Lease [Member]
Operating Leased Assets [Line Items]
2,016	686
2,017	740
Total	1,426
Stamford Operating Lease [Member]
Operating Leased Assets [Line Items]
2,016	192
2,017	875
2,018	1,093
2,019	1,217
2,020	1,241
Thereafter	3,650
Total	$ 8,268

Commitments and Contingencies48

Commitments and Contingencies - Schedule of Contractual Obligations and Commitments (Parenthetical) (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Operating Leased Assets [Line Items]
Capitalized Lease renovation expenses	$ 1,070	$ 1,263
Shelton Operating Lease [Member]
Operating Leased Assets [Line Items]
Additional amortization expense	$ 539
Additional loss per share	$ 0.02
Stamford Operating Lease [Member]
Operating Leased Assets [Line Items]
Capitalized Lease renovation expenses	$ 495