Cara Therapeutics (CARA) 10-Q 9 Nov 15 2015 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Nov. 04, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
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	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		27,231,583

Condensed Balance Sheets

Condensed Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 111,116	$ 52,663
Income tax receivable	450	200
Other receivables	2,143
Prepaid expenses	1,971	287
Total current assets	115,680	53,150
Property and equipment, net	1,517	2,084
Restricted cash	700	700
Total assets	117,897	55,934
Current liabilities:
Accounts payable and accrued expenses	3,374	1,946
Deferred revenue		1,452
Total current liabilities	3,374	3,398
Deferred lease obligation	$ 660	$ 874
Commitments and contingencies (Note 11)
Stockholders' equity:
Preferred stock; $0.001 par value; 5,000,000 shares authorized at September 30, 2015 and December 31, 2014, zero shares issued and outstanding at September 30, 2015 and December 31, 2014
Common stock; $0.001 par value; 100,000,000 shares authorized at September 30, 2015 and December 31, 2014, 27,231,583 shares and 22,802,039 shares issued and outstanding at September 30, 2015 and December 31, 2014, respectively	$ 27	$ 23
Additional paid-in capital	209,197	131,840
Accumulated deficit	(95,361)	(80,201)
Total stockholders' equity	113,863	51,662
Total liabilities and stockholders' equity	$ 117,897	$ 55,934

Condensed Balance Sheets (Paren

Condensed Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2015	Dec. 31, 2014
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	27,231,583	22,802,039
Common stock, shares outstanding	27,231,583	22,802,039

Condensed Statements of Operati

Condensed Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenue:
License and milestone fees	$ 1,710		$ 1,710	$ 302
Collaborative revenue	730	$ 1,125	2,093	1,802
Clinical compound revenue			0	159
Total revenue	2,440	1,125	3,803	2,263
Operating expenses:
Research and development	5,584	6,208	13,653	11,609
General and administrative	1,865	1,520	5,609	4,390
Total operating expenses	7,449	7,728	19,262	15,999
Operating loss	(5,009)	(6,603)	(15,459)	(13,736)
Interest income	22	26	49	104
Loss before benefit from income taxes	(4,987)	(6,577)	(15,410)	(13,632)
Benefit from income taxes	200	32	250	59
Net loss	$ (4,787)	$ (6,545)	$ (15,160)	$ (13,573)
Net loss per share -Basic and Diluted	$ (0.19)	$ (0.29)	$ (0.64)	$ (0.67)
Weighted average shares:
Basic and Diluted	25,545,164	22,713,040	23,737,443	20,351,005

Condensed Statements of Convert

Condensed Statements of Convertible Preferred Stock and Stockholders' (Deficit) Equity - USD ($) $ in Thousands	Total	Convertible Preferred Stock [Member]	Initial Public Offering [Member]	Follow On Public Offering [Member]	Common Stock [Member]	Common Stock [Member]Initial Public Offering [Member]	Common Stock [Member]Follow On Public Offering [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member]Initial Public Offering [Member]	Additional Paid-in Capital [Member]Follow On Public Offering [Member]	Accumulated Deficit [Member]
Balance, Value at Dec. 31, 2013		$ 65,586
Balance, Value at Dec. 31, 2013	$ (54,075)				$ 4			$ 8,377			$ (62,456)
Balance, Shares at Dec. 31, 2013		29,186,929
Balance, Shares at Dec. 31, 2013					4,288,243
Sale of common stock, net of underwriting discounts and commissions and offering expenses, Value			$ 56,247			$ 6			$ 56,241
Sale of common stock, net of underwriting discounts and commissions and offering expenses, Shares						5,750,000
Preferred stock converted to common shares, Value	65,586	$ (65,586)			$ 13			65,573
Preferred stock converted to common shares, Shares		29,186,929			12,554,171
Stock-based compensation expense	1,031							1,031
Shares issued upon exercise of stock options, Value	119							119
Shares issued upon exercise of stock options, Shares					179,800
Shares issued upon cashless exercise of warrants, Shares					6,383
Net loss	(13,573)										(13,573)
Balance, Value at Sep. 30, 2014	55,335				$ 23			131,341			(76,029)
Balance, Shares at Sep. 30, 2014					22,778,597
Balance, Value at Dec. 31, 2014	51,662				$ 23			131,840			(80,201)
Balance, Shares at Dec. 31, 2014					22,802,039
Sale of common stock, net of underwriting discounts and commissions and offering expenses, Value				$ 75,231			$ 4			$ 75,227
Sale of common stock, net of underwriting discounts and commissions and offering expenses, Shares							4,327,956
Stock-based compensation expense	1,807							1,807
Shares issued upon exercise of stock options, Value	323							323
Shares issued upon exercise of stock options, Shares					101,588
Net loss	(15,160)										(15,160)
Balance, Value at Sep. 30, 2015	$ 113,863				$ 27			$ 209,197			$ (95,361)
Balance, Shares at Sep. 30, 2015					27,231,583

Condensed Statements of Conver6

Condensed Statements of Convertible Preferred Stock and Stockholders' (Deficit) Equity (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Initial Public Offering [Member]
Sale of common stock, per share		$ 11
Underwriting discounts and commissions and offering expenses		$ 7,003
Follow On Public Offering [Member]
Sale of common stock, per share	$ 18.60
Underwriting discounts and commissions and offering expenses	$ 5,269

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Operating activities
Net loss	$ (15,160)	$ (13,573)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	1,807	1,031
Depreciation and amortization	580	590
Deferred rent costs	(214)	(194)
Changes in operating assets and liabilities:
Income tax receivable	(250)	(28)
Other receivables	(2,143)
Prepaid expenses	(1,649)	240
Accounts payable and accrued expenses	1,171	1,647
Deferred revenue	(1,452)	(1,531)
Net cash used in operating activities	(17,310)	(11,818)
Investing activities
Purchases of property and equipment	(13)	(27)
Net cash used in investing activities	(13)	(27)
Financing activities
Proceeds from initial public offering, net of issuance costs		57,762
Proceeds from follow-on offering of common stock, net of issuance costs	75,453
Proceeds from the exercise of stock options	323	119
Net cash provided by financing activities	75,776	57,881
Net cash increase for the period	58,453	46,036
Cash and cash equivalents at beginning of period	52,663	12,357
Cash and cash equivalents at end of period	111,116	58,393
Noncash financing activities
Conversion of convertible preferred stock to common stock		65,586
Reclassification of prepaid IPO costs paid in 2013		1,465
Unpaid IPO/ follow-on offering issuance costs	$ 222	$ 50

Business

Business	9 Months Ended
	Sep. 30, 2015
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 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 September 30, 2015, the Company has raised aggregate net proceeds of approximately $204,800 from several rounds of equity financing, including its follow-on offering, which closed in August 2015 (see Note 5 of Notes to Condensed Financial Statements), and the issuance of debt. In addition, the Company earned approximately $32,500 (of which approximately $2,100 was due to the Company as of September 30, 2015 and received in October 2015) under its license agreements for CR845, primarily with Maruishi Pharmaceutical Co. Ltd. (“Maruishi”) and Chong Kun Dang Pharmaceutical Corp. (“CKD”), and for 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 earnings described above, in April 2013, the Company received an upfront payment of $15,000, and in August 2014 and September 2015, the Company received an additional $480 and was due an additional $1,725 (net of contractual foreign currency exchange adjustments), respectively, in milestone payments. In connection with the license of rights to CR845 in South Korea to CKD and as part of the earnings described above, in 2012, the Company received aggregate upfront and milestone payments of $1,190, and in August 2015 and September 2015, the Company received an additional $209 and was due an additional $417 (net of South Korean withholding taxes), respectively, in milestone payments. The Company has incurred substantial net losses and negative cash flows from operating activities in nearly every fiscal period since inception. As of September 30, 2015, the Company had unrestricted cash and cash equivalents of $111,116 and an accumulated deficit of $95,361. The Company had net cash used in operating activities of $17,310 and $11,818 for the nine months ended September 30, 2015 and 2014, respectively. The Company expects that cash and cash equivalents at September 30, 2015 will be sufficient to fund its operations beyond one year. The Company recognized net losses of $4,787 and $15,160 for the three and nine months ended September 30, 2015, respectively, and $6,545 and $13,573 for the three and nine months ended September 30, 2014, respectively, and expects to incur additional net losses and negative cash flows for the full year ending December 31, 2015 and for the foreseeable future. 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 U.S. Food and Drug Administration (“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	9 Months Ended
	Sep. 30, 2015
Accounting Policies [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 (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 (“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, 2014 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, 2014. 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 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 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, 2014. Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update 2014-09, Revenue from Contracts with Customers (Topic 606) Revenue from Contracts with Customers (Topic 606) Deferral of the Effective Date During April 2015, the FASB issued Accounting Standards Update 2015-03 (“ASU 2015-03”) Interest—Imputation of Interest (Subtopic 835-30) Simplifying the Presentation of Debt Issuance Costs Interest—Imputation of Interest (Subtopic 835-30) Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements Reclassifications Certain revenue amounting to $159 within the Statements of Operations for the nine months ended September 30, 2014 has been reclassified from Collaborative revenue to Clinical compound revenue to conform to the current year presentation.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Fair Value Measurements As of September 30, 2015 and December 31, 2014, the Company’s financial instruments consisted of cash and cash equivalents, restricted cash, accounts payable and accrued liabilities. As of September 30, 2015, the Company’s financial instruments also included other receivables (see Note 6 of Notes to Condensed Financial Statements, Collaborations Current accounting guidance defines fair value, establishes a framework for measuring fair value in accordance with Accounting Standards Codification (“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 market assumptions and are classified into the following fair value hierarchy: • 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. The following table summarizes the financial assets measured at fair value on a recurring basis as of September 30, 2015 and December 31, 2014. September 30, 2015 December 31, 2014 Level 1 Level 1 Financial assets Cash equivalents: Money market savings account $ 110,486 $ 52,663 Restricted cash: Bank certificate of deposit 700 700 Other receivables 2,143 — Total $ 113,329 $ 53,363

Prepaid Expenses

Prepaid Expenses	9 Months Ended
	Sep. 30, 2015
Text Block [Abstract]
Prepaid Expenses	4. Prepaid expenses As of September 30, 2015, prepaid expenses were $1,971, consisting of $294 of prepaid insurance, $1,627 of prepaid research and development (“R&D”) clinical costs and $50 of other prepaid costs. As of December 31, 2014, prepaid expenses and other current assets were $287, consisting of $92 of prepaid insurance, $177 of prepaid R&D clinical costs and $18 of other prepaid costs.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2015
Equity [Abstract]
Stockholders' Equity	5. Stockholders’ Equity On July 29, 2015, the Company entered into an underwriting agreement (the “Underwriting Agreement”) with Stifel, Nicolaus & Company, Incorporated and Piper Jaffray & Co., as representatives of the several underwriters named therein, relating to the issuance and sale by the Company of 3,763,440 shares of its common stock (the “Offering”). The Offering was made pursuant to the Company’s Registration Statement on Form S-3 (File No. 333-203072), filed with the SEC on March 27, 2015 and declared effective on May 13, 2015, and a related prospectus supplement dated July 29, 2015, which was filed with the SEC on July 30, 2015. As part of the Offering, the Company granted the underwriters an option to purchase 564,516 additional shares of common stock. On August 4, 2015, the Company closed the Offering, including the full exercise of the underwriters’ option to purchase 564,516 additional shares of common stock, at a public offering price of $18.60 per share. The Company received net proceeds of approximately $75,231, after deducting the underwriting discounts and commissions and offering expenses paid or payable by the Company.

Collaborations

Collaborations	9 Months Ended
	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Collaborations	6. Collaborations Chong Kun Dang Pharmaceutical Corporation In April, 2012, the Company entered into a license agreement with CKD (the “CKD Agreement”) that provides CKD with the exclusive rights to develop, manufacture and commercialize products containing CR845 in South Korea. Under the CKD Agreement, the Company is eligible to receive milestone payments totaling $3,750, relating to pre-defined clinical development ($2,250) and regulatory events ($1,500), as well as royalties on sales of any marketed products containing CR845. The Company has accounted for the milestones under ASC 605 Revenue Recognition – Milestone Method In July 2015, the Company met the milestone criteria, as set forth in the CKD Agreement, for completion of a Phase 1b trial of Oral CR845 in the United States. As a result, in August 2015, the Company received a milestone payment of $209 (net of South Korean withholding tax of $41) from CKD. In September 2015, the Company met the milestone criteria, as set forth in the CKD Agreement, for completion of a Phase 2 trial of CR845 in uremic pruritus patients in the United States. As a result, as of September 30, 2015, the Company was due a milestone payment of $417 (net of South Korean withholding tax of $83) from CKD. In October 2015, the Company received the milestone payment from CKD. Both milestones were considered to be substantive and the full amount of the milestone payments was recognized as milestone revenue when the milestones were achieved. The next potential milestone that the Company could be entitled to receive under the CKD Agreement will be a clinical development milestone for completion of a Phase 3 trial of CR845 in the United States in uremic pruritus patients. If achieved, this milestone will result in a payment of $750 being due to the Company. Maruishi Pharmaceutical Co., Ltd. In April 2013, the Company entered into a license agreement with Maruishi (the “Maruishi Agreement”) under which the Company granted Maruishi an exclusive license to develop, manufacture, and commercialize drug products containing CR845 for acute pain and uremic pruritus in Japan. Under the Maruishi Agreement, the Company and Maruishi are required to use commercially reasonable efforts, at their own expense, to develop, obtain regulatory approval for and commercialize CR845 in the United States and Japan, respectively. In addition, the Company provided Maruishi specific clinical development services for CR845 used in Maruishi’s field of use. The Company has identified two deliverables under ASC 605-25, Revenue Recognition — Multiple Element Arrangements Along with the R&D services performed by the Company for Maruishi, the Company supplied Maruishi with CR845 clinical material as an accommodation. The Company had previously entered into manufacturing and service agreements with third parties to manufacture CR845. Payments made by the Company to third parties based on firm and fixed commitments by Maruishi to purchase CR845 from the Company were capitalized as prepaid expense. During the manufacturing process, title and risk of loss remained with the third party until the Company paid in full for the material. Once the Company had title to the CR845 and had delivered it to Maruishi, prepaid expense related to that CR845 was reduced with an offset to R&D expense. At that time, Maruishi reimbursed the Company for its external and internal costs for purchasing CR845 and processing the sale to Maruishi and the Company recognized clinical compound revenue for the reimbursement amount. During the nine months ended September 30, 2015 and 2014, the Company recognized clinical compound revenue of $0 and $159, respectively. Deposits received from Maruishi prior to delivery of CR845 were recorded as deferred revenue. Under the terms of the Maruishi Agreement, the Company is also entitled to receive aggregate milestone payments of $8,000 for events performed by Maruishi in Japan and $2,500 for events performed by the Company in the United States. At the time of execution of the Maruishi Agreement, there was significant uncertainty as to whether the stated milestones would be achieved. In conjunction with this uncertainty, the Company has determined that the milestones achieved in the United States are substantive in nature as they are commensurate with the enhancement of value of the delivered license as they relate to clinical success and advancement within the FDA drug development platform. The Company will account for those milestone payments under ASC 605-28 Revenue Recognition – Milestone Method In September 2015, Maruishi initiated a Phase 2 clinical trial of CR845 in Japan for uremic pruritus, which triggered a $1,725 milestone payment (net of contractual foreign currency exchange adjustments of $275) to the Company. As of September 30, 2015, such payment was due to the Company and was received in October 2015. At the time of achievement of the milestone, the Company had delivered all deliverables under the Maruishi Agreement. Since the milestone was achieved in Japan, it was deemed not to be substantive. Accordingly, the Company recognized $1,084 as milestone revenue and $641 as collaborative revenue during both the three months and nine months ended September 30, 2015 in connection with achievement of this milestone. The next potential milestone that the Company could be entitled to receive under the Maruishi Agreement will be a clinical development milestone for the completion of the first Phase 3 pivotal trial of CR845 in acute pain in the United States. If achieved, this milestone will result in a payment of $1,000 being due to the Company. The R&D services deliverable was completed in July 2015. As of September 30, 2015 and December 31, 2014, the Company had $0 and $1,452, respectively, of deferred revenue pursuant to the R&D services deliverable under the Maruishi Agreement. Amortization of deferred revenue pursuant to the R&D services deliverable to collaborative revenue was $89 and $1,125, for the three months ended September 30, 2015 and 2014, respectively, and $1,452 and $1,802 for the nine months ended September 30, 2015 and 2014, respectively. The Company incurred R&D expense related to the Maruishi Agreement of $108 and $1,326 (both consisting of clinical trial costs related to the R&D services deliverable) during the three months ended September 30, 2015 and 2014, respectively. During the nine months ended September 30, 2015 and 2014, the Company incurred R&D expense related to the Maruishi Agreement of $1,583 (consisting of clinical trial costs related to the R&D services deliverable) and $2,438 (consisting of $2,324 of clinical trial costs related to the R&D services deliverable and $114 related to the cost of clinical compound sold to Maruishi), respectively.

Accounts Payable and Accrued Ex

Accounts Payable and Accrued Expenses	9 Months Ended
	Sep. 30, 2015
Payables and Accruals [Abstract]
Accounts Payable and Accrued Expenses	7. Accounts Payable and Accrued Expenses Accounts payable and accrued expenses consist of the following: September 30, 2015 December 31, 2014 Accounts payable $ 1,263 $ 515 Accrued research projects 969 549 Accrued professional fees 348 266 Accrued compensation and benefits 708 504 Accrued other 86 112 Total $ 3,374 $ 1,946

Net Loss Per Share

Net Loss Per Share	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Net Loss Per Share	8. 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 converted or exercised during the period, when the effect is dilutive. Potential common stock equivalents include convertible preferred stock and outstanding stock options and stock warrants, which are included using the treasury stock method when dilutive. The computation of diluted net loss per share does not include common stock equivalents since such inclusion would be anti-dilutive. For the three and nine months ended September 30, 2015 and 2014, 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 September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Basic: Weighted average common shares outstanding 25,545,164 22,713,040 23,737,443 20,351,005 Diluted: Weighted average common shares outstanding - Basic 25,545,164 22,713,040 23,737,443 20,351,005 Common stock options* — — — — Common stock warrants* — — — — Convertible preferred stock* — — — — Denominator for diluted net loss per share 25,545,164 22,713,040 23,737,443 20,351,005 * 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 September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Net loss $ (4,787 ) $ (6,545 ) $ (15,160 ) $ (13,573 ) Weighted-average common shares outstanding: Basic and Diluted 25,545,164 22,713,040 23,737,443 20,351,005 Net loss per share, Basic and Diluted $ (0.19 ) $ (0.29 ) $ (0.64 ) $ (0.67 ) As of September 30, 2015 and 2014, 1,541,772 and 964,360 stock options were outstanding, respectively, 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	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	9. Stock-Based Compensation 2014 Equity Incentive Plan The Company’s 2014 Equity Incentive Plan (the “2014 Plan”) is administered by the Company’s Board of Directors or a duly authorized committee thereof (the “Plan Administrator”). The 2014 Plan provides for the grant of incentive stock options, non-statutory The aggregate number of shares of the Company’s common stock reserved for issuance under the 2014 Plan automatically increases 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, 2015, the aggregate number of shares of common stock that may be issued pursuant to stock awards under the Company’s 2014 Equity Incentive Plan automatically increased from 1,600,000 to 2,284,061. 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 25,000 and 629,000 stock options during the three and nine months ended September 30, 2015, respectively, and 40,000 and 654,000 stock options during the three and nine months ended September 30, 2014, respectively. The fair values of stock options granted during the three and nine months ended September 30, 2015 and 2014 were estimated as of the dates of grant using the Black-Scholes option pricing model with the following assumptions: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Risk-free interest rate 1.77% 1.92% 1.43% - 1.89% 1.80% - 2.72% Expected volatility 64.1% 65.0% 64.0% - 67.1% 65.0% - 71.0% Expected dividend yield 0% 0% 0% 0% Expected life of employee options (in years) 6.25 6.25 6.25 6.25 Expected life of nonemployee options (in years) 10 10 10 10 The weighted average grant date fair value of options granted to employees and members of the Company’s Board of Directors for their service during the three and nine months ended September 30, 2015 was $13.30 and $6.60, respectively, and during the three and nine months ended September 30, 2014 was $8.01 and $7.58, respectively. The weighted average fair value of outstanding unvested options that had been granted to nonemployee consultants as re-measured During the three and nine months ended September 30, 2015 and 2014, the Company recognized compensation expense relating to stock options, as follows: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Research and development $ 283 $ 38 $ 761 $ 269 General and administrative 378 184 1,046 762 Total stock option expense $ 661 $ 222 $ 1,807 $ 1,031 A summary of stock option award activity as of and for the nine months ended September 30, 2015 is presented below: Number of Weighted Outstanding, December 31, 2014 1,022,360 $ 8.16 Granted 629,000 10.91 Exercised (101,588 ) 3.18 Expired (8,000 ) 0.25 Outstanding, September 30, 2015 1,541,772 9.65 Options exercisable, September 30, 2015 433,806 $ 7.00

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Income Taxes	10. Income Taxes For the three months ended September 30, 2015 and 2014, pre-tax losses were $4,987 and $6,577, respectively, and for the nine months ended September 30, 2015 and 2014, pre-tax losses were $15,410 and $13,632, respectively. The Company recognized a full tax valuation allowance against net deferred tax assets at September 30, 2015 and December 31, 2014. The benefit from income taxes of $200 and $32 for the three months ended September 30, 2015 and 2014, respectively, and $250 and $59 for the nine months ended September 30, 2015 and 2014, respectively, relates to state research and development tax credits exchanged for cash pursuant to the Connecticut Research and Development Tax Credit Exchange Program, which permits qualified small businesses engaged in research and development activities within Connecticut to exchange their unused research and development tax credits for a cash amount equal to 65% of the value of the exchanged credits.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	11. Commitments and Contingencies Contractual obligations and commitments as of September 30, 2015 were as follows: Payment Due for the Year Ending December 31, 2015 2016 2017 2018 Thereafter Total Operating lease (1) $ 226 $ 913 $ 740 $ — $ — $ 1,879 (1) The Company leases its operating facility located in Shelton, Connecticut.

Basis of Presentation (Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2015
Accounting Policies [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 (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 (“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, 2014 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, 2014.
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 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 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, 2014.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update 2014-09, Revenue from Contracts with Customers (Topic 606) Revenue from Contracts with Customers (Topic 606) Deferral of the Effective Date During April 2015, the FASB issued Accounting Standards Update 2015-03 (“ASU 2015-03”) Interest—Imputation of Interest (Subtopic 835-30) Simplifying the Presentation of Debt Issuance Costs Interest—Imputation of Interest (Subtopic 835-30) Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements
Reclassifications	Reclassifications Certain revenue amounting to $159 within the Statements of Operations for the nine months ended September 30, 2014 has been reclassified from Collaborative revenue to Clinical compound revenue to conform to the current year presentation.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Summary of Financial Assets Measured at Fair Value on Recurring Basis	The following table summarizes the financial assets measured at fair value on a recurring basis as of September 30, 2015 and December 31, 2014. September 30, 2015 December 31, 2014 Level 1 Level 1 Financial assets Cash equivalents: Money market savings account $ 110,486 $ 52,663 Restricted cash: Bank certificate of deposit 700 700 Other receivables 2,143 — Total $ 113,329 $ 53,363

Accounts Payable and Accrued 21

Accounts Payable and Accrued Expenses (Tables)	9 Months Ended
	Sep. 30, 2015
Payables and Accruals [Abstract]
Schedule of Accounts Payable and Accrued Expenses	Accounts payable and accrued expenses consist of the following: September 30, 2015 December 31, 2014 Accounts payable $ 1,263 $ 515 Accrued research projects 969 549 Accrued professional fees 348 266 Accrued compensation and benefits 708 504 Accrued other 86 112 Total $ 3,374 $ 1,946

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	9 Months Ended
	Sep. 30, 2015
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 September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Basic: Weighted average common shares outstanding 25,545,164 22,713,040 23,737,443 20,351,005 Diluted: Weighted average common shares outstanding - Basic 25,545,164 22,713,040 23,737,443 20,351,005 Common stock options* — — — — Common stock warrants* — — — — Convertible preferred stock* — — — — Denominator for diluted net loss per share 25,545,164 22,713,040 23,737,443 20,351,005 * 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 September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Net loss $ (4,787 ) $ (6,545 ) $ (15,160 ) $ (13,573 ) Weighted-average common shares outstanding: Basic and Diluted 25,545,164 22,713,040 23,737,443 20,351,005 Net loss per share, Basic and Diluted $ (0.19 ) $ (0.29 ) $ (0.64 ) $ (0.67 )

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2015
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 and nine months ended September 30, 2015 and 2014 were estimated as of the dates of grant using the Black-Scholes option pricing model with the following assumptions: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Risk-free interest rate 1.77% 1.92% 1.43% - 1.89% 1.80% - 2.72% Expected volatility 64.1% 65.0% 64.0% - 67.1% 65.0% - 71.0% Expected dividend yield 0% 0% 0% 0% Expected life of employee options (in years) 6.25 6.25 6.25 6.25 Expected life of nonemployee options (in years) 10 10 10 10
Summary of Compensation Expense Relating to Stock Options	During the three and nine months ended September 30, 2015 and 2014, the Company recognized compensation expense relating to stock options, as follows: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Research and development $ 283 $ 38 $ 761 $ 269 General and administrative 378 184 1,046 762 Total stock option expense $ 661 $ 222 $ 1,807 $ 1,031
Summary of Stock Option Award Activity	A summary of stock option award activity as of and for the nine months ended September 30, 2015 is presented below: Number of Weighted Outstanding, December 31, 2014 1,022,360 $ 8.16 Granted 629,000 10.91 Exercised (101,588 ) 3.18 Expired (8,000 ) 0.25 Outstanding, September 30, 2015 1,541,772 9.65 Options exercisable, September 30, 2015 433,806 $ 7.00

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Schedule of Contractual Obligations and Commitments	Contractual obligations and commitments as of September 30, 2015 were as follows: Payment Due for the Year Ending December 31, 2015 2016 2017 2018 Thereafter Total Operating lease (1) $ 226 $ 913 $ 740 $ — $ — $ 1,879 (1) The Company leases its operating facility located in Shelton, Connecticut.

Business - Additional Informati

Business - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended				3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015	Aug. 31, 2015	Aug. 31, 2014	Apr. 30, 2013	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013
Nature Of Business [Line Items]
Date of formation							Jul. 2, 2004
Proceeds from equity and debt financing							$ 204,800
Upfront and milestone payments earned in connection with license agreements							32,500
Amount due from upfront and milestone payments with license agreements	$ 2,100				$ 2,100		2,100
Upfront and milestone payments related to license agreement					1,710		1,710	$ 302
Net cash used in operating activities							17,310	11,818
Accumulated deficit	95,361				95,361		95,361			$ 80,201
Unrestricted cash and cash equivalents	111,116				111,116	$ 58,393	111,116	58,393		$ 52,663	$ 12,357
Net loss					4,787	$ 6,545	$ 15,160	$ 13,573
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			$ 480
Amount due from milestone payments net of contractual foreign currency exchange adjustments	1,725
Upfront and milestone payments related to license agreement					$ 1,084		$ 1,084
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

Basis of Presentation - Additio

Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Accounting Policies [Abstract]
Clinical compound revenue	$ 0	$ 159

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Detail) - Recurring [Member] - Level 1 [Member] - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Financial assets
Other receivables	$ 2,143
Total	113,329	$ 53,363
Money Market Savings Account [Member]
Financial assets
Cash equivalents	110,486	52,663
Bank Certificate of Deposit [Member]
Financial assets
Restricted cash	$ 700	$ 700

Prepaid Expenses - Additional I

Prepaid Expenses - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid expenses	$ 1,971	$ 287
Prepaid insurance	294	92
Prepaid R&D clinical costs	1,627	177
Other prepaid costs	$ 50	$ 18

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Aug. 04, 2015	Sep. 30, 2015	Jul. 29, 2015	Dec. 31, 2014
Subsidiary, Sale of Stock [Line Items]
Common stock, shares issued		27,231,583		22,802,039
Public offering price per share	$ 18.60
Net proceeds from offering of common stock	$ 75,231
Offering [Member]
Subsidiary, Sale of Stock [Line Items]
Common stock, shares issued			3,763,440
Underwriters [Member] | Maximum [Member]
Subsidiary, Sale of Stock [Line Items]
Common stock, shares issued	564,516

Collaborations - Additional Inf

Collaborations - Additional Information (Detail) $ in Thousands	1 Months Ended			3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015USD ($)	Aug. 31, 2015USD ($)	Aug. 31, 2014USD ($)	Sep. 30, 2015USD ($)	Sep. 30, 2014USD ($)	Sep. 30, 2015USD ($)Deliverables	Sep. 30, 2014USD ($)	Dec. 31, 2012USD ($)	Dec. 31, 2014USD ($)	Apr. 30, 2012USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Clinical compound revenue						$ 0	$ 159
License and milestone fee revenue				$ 1,710		1,710	302
Collaborative revenue				730	$ 1,125	2,093	1,802
Deferred R&D service revenue									$ 1,452
Research and development expense				5,584	6,208	13,653	11,609
Chong Kun Dang Pharmaceutical Corporation [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Milestone payments receivable										$ 3,750
Milestone payment received	$ 417	$ 209
South Korean Withholding tax	83	$ 41
Next potential milestone that could be received						$ 750
License and milestone fee revenue								$ 1,190
Chong Kun Dang Pharmaceutical Corporation [Member] | Clinical Development [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Milestone payments receivable										2,250
Chong Kun Dang Pharmaceutical Corporation [Member] | Regulatory Events [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Milestone payments receivable										$ 1,500
Maruishi Pharmaceutical Co., Ltd. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Milestone payment received			$ 480
Number of deliverables for revenue recognized | Deliverables						2
Revenue recognized from nonsubstantive milestones						$ 8,000
Revenue recognized from substantive milestones						2,500
Amount due from milestone payments net of contractual foreign currency exchange adjustments	1,725
Contractual foreign currency exchange adjustments	275
License and milestone fee revenue				1,084		1,084
Collaborative revenue				641		641
Deferred R&D service revenue	$ 0			0		0			$ 1,452
Clinical trial costs related to the R&D services deliverable				108	1,326	1,583	2,324
Research and development expense							2,438
Cost of clinical compound sold to Maruishi							114
Maruishi Pharmaceutical Co., Ltd. [Member] | Clinical Development [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Next potential milestone that could be received						1,000
Maruishi Pharmaceutical Co., Ltd. [Member] | Amortization Of Deferred Revenue [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaborative revenue				$ 89	$ 1,125	$ 1,452	$ 1,802

Accounts Payable and Accrued 31

Accounts Payable and Accrued Expenses - Schedule of Accounts Payable and Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Accounts payable	$ 1,263	$ 515
Accrued research projects	969	549
Accrued professional fees	348	266
Accrued compensation and benefits	708	504
Accrued other	86	112
Total	$ 3,374	$ 1,946

Net Loss Per Share - Computatio

Net Loss Per Share - Computation of Denominators Used in Net Loss Per Share (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Basic:
Weighted average common shares outstanding	25,545,164	22,713,040	23,737,443	20,351,005
Diluted:
Weighted average common shares outstanding - Basic	25,545,164	22,713,040	23,737,443	20,351,005
Common stock options	0	0	0	0
Common stock warrants	0	0	0	0
Convertible preferred stock	0	0	0	0
Denominator for diluted net loss per share	25,545,164	22,713,040	23,737,443	20,351,005

Net Loss Per Share - Computat33

Net Loss Per Share - Computation of Basic and Diluted Net Loss Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share [Abstract]
Net loss	$ (4,787)	$ (6,545)	$ (15,160)	$ (13,573)
Weighted-average common shares outstanding:
Basic and Diluted	25,545,164	22,713,040	23,737,443	20,351,005
Net loss per share, Basic and Diluted	$ (0.19)	$ (0.29)	$ (0.64)	$ (0.67)

Net Loss Per Share - Additional

Net Loss Per Share - Additional Information (Detail) - shares	Sep. 30, 2015	Sep. 30, 2014
Common Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive common stock equivalents	1,541,772	964,360

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Jan. 01, 2015	Dec. 31, 2014
Employees and Members of Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of options granted	$ 13.30	$ 8.01	$ 6.60	$ 7.58
Nonemployee Consultants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of outstanding unvested options	$ 10.87	$ 5.87	$ 9.03	$ 11.79
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					2,284,061	1,600,000
Options granted	25,000	40,000	629,000	654,000
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		30,000,000

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Assumptions Used in Black-Scholes Option Pricing Model (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.77%	1.92%
Risk-free interest rate, minimum			1.43%	1.80%
Risk-free interest rate, maximum			1.89%	2.72%
Expected volatility	64.10%	65.00%
Expected volatility, minimum			64.00%	65.00%
Expected volatility, maximum			67.10%	71.00%
Expected dividend yield	0.00%	0.00%	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	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	10 years	10 years

Stock-Based Compensation - Su37

Stock-Based Compensation - Summary of Compensation Expense Relating to Stock Options (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock option expense	$ 661	$ 222	$ 1,807	$ 1,031
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock option expense	283	38	761	269
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock option expense	$ 378	$ 184	$ 1,046	$ 762

Stock-Based Compensation - Su38

Stock-Based Compensation - Summary of Stock Option Award Activity (Detail) - 2014 Equity Incentive Plan [Member] - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Outstanding, December 31, 2014			1,022,360
Number of Shares, Granted	25,000	40,000	629,000	654,000
Number of Shares, Exercised			(101,588)
Number of Shares, Expired			(8,000)
Number of Shares, Outstanding, September 30, 2015	1,541,772		1,541,772
Number of Shares, Options exercisable, September 30, 2015	433,806		433,806
Weighted Average Exercise Price, Outstanding, December 31, 2014			$ 8.16
Weighted Average Exercise Price, Granted			10.91
Weighted Average Exercise Price, Exercised			3.18
Weighted Average Exercise Price, Expired			0.25
Weighted Average Exercise Price, Outstanding, September 30, 2015	$ 9.65		9.65
Weighted Average Exercise Price, Options exercisable, September 30, 2015	$ 7		$ 7

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Tax Disclosure [Abstract]
Pre-tax losses	$ 4,987	$ 6,577	$ 15,410	$ 13,632
Benefit from income taxes	$ 200	$ 32	$ 250	$ 59
Percentage of value of research and development tax credits exchanged for cash			65.00%

Commitments and Contingencies -

Commitments and Contingencies - Schedule of Contractual Obligations and Commitments (Detail) $ in Thousands	Sep. 30, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,015	$ 226
2,016	913
2,017	740
2,018	0
Thereafter	0
Total	$ 1,879