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Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2014	Mar. 20, 2015	Jun. 30, 2014
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2014
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Trading Symbol	CARA
Entity Registrant Name	Cara Therapeutics, Inc.
Entity Central Index Key	0001346830
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		22,824,919
Entity Public Float			$ 226,478,179

Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 52,663	$ 12,357
Income tax receivable	200	61
Prepaid expenses	287	2,140
Total current assets	53,150	14,558
Property and equipment, net	2,084	2,825
Restricted cash	700	700
Total assets	55,934	18,083
Current liabilities:
Accounts payable and accrued expenses	1,946	1,958
Deferred Revenue	1,452	3,475
Total current liabilities	3,398	5,433
Deferred lease obligation	874	1,139
Commitments and contingencies (Note 18)
Convertible Preferred stock; $0.001 par value; zero shares and 29,402,200 shares authorized at December 31, 2014 and December 31, 2013, respectively; zero shares and 29,186,929 shares at December 31, 2014 and December 31, 2013 issued and outstanding, respectively; aggregate liquidation preference of zero and $65,969 at December 31, 2014 and December 31, 2013, respectively		65,586
Stockholders' (deficit) equity:
Preferred stock; $0.001 par value; 5,000,000 shares and zero shares authorized at December 31, 2014 and December 31, 2013, respectively; zero shares issued and outstanding at December 31, 2014 and December 31, 2013, respectively
Common stock; $0.001 par value; 100,000,000 shares and 50,000,000 shares authorized at December 31, 2014 and December 31, 2013, respectively; 22,802,039 shares and 4,288,243 shares issued and outstanding at December 31, 2014 and December 31, 2013, respectively	23	4
Additional paid-in capital	131,840	8,377
Accumulated deficit	(80,201)	(62,456)
Total stockholders' (deficit) equity	51,662	(54,075)
Total liabilities, convertible preferred stock and stockholders' (deficit) equity	$ 55,934	$ 18,083

Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2014	Feb. 05, 2014	Jan. 30, 2014	Jan. 16, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]
Convertible Preferred stock, par value	$ 0.001				$ 0.001
Convertible Preferred stock, shares authorized	0				29,402,200	26,636,118
Convertible Preferred stock, shares issued	0	29,186,929			29,186,929	26,636,118
Convertible Preferred stock, shares outstanding	0	29,186,929			29,186,929	26,636,118
Convertible Preferred stock, aggregate liquidation preference	$ 0				$ 65,969	$ 58,530
Preferred stock, par value	$ 0.001			$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000			5,000,000	0
Preferred stock, shares issued	0				0
Preferred stock, shares outstanding	0				0
Common stock, par value	$ 0.001			$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000			100,000,000	50,000,000
Common stock, shares issued	22,802,039		5,750,000		4,288,243
Common stock, shares outstanding	22,802,039				4,288,243

Statements of Operations - USD ($) $ in Thousands	12 Months Ended
Statements of Operations - USD ($) $ in Thousands	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue:
License and milestone fees	$ 302	$ 9,637	$ 1,190
Collaborative revenue	2,201	2,225
Clinical compound revenue	674	102
Total revenue	3,177	11,964	1,190
Operating expenses:
Research and development	15,068	8,685	4,597
General and administrative	6,181	3,516	2,829
Total operating expenses	21,249	12,201	7,426
Operating loss	(18,072)	(237)	(6,236)
Interest income (expense), net	126	(3,756)	(66)
Loss before benefit from income taxes	(17,946)	(3,993)	(6,302)
Benefit from income taxes	201	30	31
Net loss	(17,745)	(3,963)	(6,271)
Net loss available to common stockholders:
Basic and Diluted	$ (17,745)	$ (3,072)	$ (6,271)
Loss per share available to common stockholders:
Basic and Diluted	$ (0.85)	$ (0.74)	$ (1.90)
Weighted average shares:
Basic and Diluted	20,965,935	4,133,138	3,299,993

Statements of Convertible Preferred Stock and Stockholders' (Deficit) Equity - USD ($) $ in Thousands	Total	Junior Convertible Preferred Stock [Member]	Junior A Convertible Preferred Stock [Member]	Initial Public Offering [Member]	Private Placement [Member]	Common Stock [Member]	Common Stock [Member] Initial Public Offering [Member]	Common Stock [Member] Private Placement [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member] Initial Public Offering [Member]	Additional Paid-in Capital [Member] Private Placement [Member]	Accumulated Deficit [Member]	Convertible Preferred Stock [Member]	Convertible Preferred Stock [Member] Junior Convertible Preferred Stock [Member]	Convertible Preferred Stock [Member] Junior A Convertible Preferred Stock [Member]	Beneficial Conversion Feature on Convertible Promissory Notes [Member]
Balance, Value at Dec. 31, 2011	$ (52,064)					$ 3			$ 1,046			$ (53,113)
Balance, Value at Dec. 31, 2011													$ 58,168
Balance, Shares at Dec. 31, 2011						3,236,637
Balance, Shares at Dec. 31, 2011													26,462,507
Issuance of stock, Value	86								86					$ 354
Issuance of stock, Shares						58,061								173,611
Beneficial conversion feature on convertible promissory notes																$ 2,050
Balance, Value at Dec. 31, 2012	$ 58,522	$ 354											$ 58,522			2,050
Balance, Shares at Dec. 31, 2012	26,636,118	173,611											26,636,118
Stock-based compensation expense	$ 61								61
Shares issued upon exercise of stock options, Value	55								55
Shares issued upon exercise of stock options, Shares						34,000
Net loss	(6,271)											(6,271)
Balance, Value at Dec. 31, 2012	(58,133)					$ 3			1,248			(59,384)
Balance, Shares at Dec. 31, 2012						3,328,698
Preferred stock converted to common shares, Value	4,466					$ 1			3,574			891	$ (4,466)
Preferred stock converted to common shares, Shares						959,545							(2,246,743)
Issuance of stock, Value															$ 7,642
Convertible promissory notes converted to Series D preferred stock, Value													$ 3,888
Issuance of stock, Shares															2,105,263
Convertible promissory notes converted to Series D preferred stock, Shares													2,692,291
Beneficial conversion feature on convertible promissory notes																1,382
Reclassification of beneficial conversion feature	3,432								3,432							$ (3,432)
Balance, Value at Dec. 31, 2013	$ 65,586	$ 354	$ 7,642										$ 65,586
Balance, Shares at Dec. 31, 2013	29,186,929	173,611	2,105,263										29,186,929
Stock-based compensation expense	$ 123								123
Net loss	(3,963)											(3,963)
Balance, Value at Dec. 31, 2013	(54,075)					$ 4			8,377			(62,456)
Balance, Shares at Dec. 31, 2013						4,288,243
Preferred stock converted to common shares, Value	$ 65,586					$ 13			65,573				$ (65,586)
Preferred stock converted to common shares, Shares						12,554,171							(29,186,929)
Issuance of stock, Value				$ 56,297	$ 100		$ 6			$ 56,291	$ 100
Issuance of stock, Shares							5,750,000	11,442
Balance, Shares at Dec. 31, 2014	0
Stock-based compensation expense	$ 1,371								1,371
Shares issued upon exercise of stock options, Value	128								128
Shares issued upon exercise of stock options, Shares						191,800
Shares issued upon cashless exercise of warrants, Value	0					$ 0			0			0
Shares issued upon cashless exercise of warrants, Shares						6,383
Net loss	(17,745)											(17,745)
Balance, Value at Dec. 31, 2014	$ 51,662					$ 23			$ 131,840			$ (80,201)
Balance, Shares at Dec. 31, 2014						22,802,039

Statements of Convertible Preferred Stock and Stockholders' (Deficit) Equity (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2014 USD ($) $ / shares
Initial Public Offering [Member]
Sale of common stock, per share	$ 11.00
Underwriting discounts and commissions and offering expenses \| $	$ 6,953
Private Placement [Member]
Sale of common stock, per share	$ 8.74

Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
Statements of Cash Flows - USD ($) $ in Thousands	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating activities
Net loss	$ (17,745)	$ (3,963)	$ (6,271)
Adjustments to reconcile net loss to net cash (used in) provided by operations:
Stock-based compensation expense	1,371	123	61
Change in fair value of liability under license agreement		(35)	(25)
Accrued interest and amortization of beneficial conversion feature on promissory notes		3,605	25
Depreciation & amortization	783	789	1,021
Deferred rent costs	(265)	(238)	(214)
Amortization of financing costs		117	4
Loss on sale of property and equipment			286
Changes in operating assets and liabilities:
Other receivables			18
Income tax receivable	(139)	(30)	8
Prepaid expenses	388	(1,736)	73
Restricted cash			294
Accounts payable and accrued expenses	(12)	722	(1,311)
Deferred revenue	(2,023)	3,475
Net cash (used in) provided by operating activities	(17,642)	2,829	(6,031)
Investing activities
Purchases of property and equipment	(42)	(5)
Proceeds from sale of property and equipment			511
Net cash (used in) provided by investing activities	(42)	(5)	511
Financing activities
Proceeds from convertible promissory notes		1,462	2,538
Financing costs on convertible promissory notes		(70)	(47)
Repayment of convertible promissory notes		(311)
Repayment of long-term debt		(307)	(446)
Proceeds from sale of common stock	100		86
Proceeds from the exercise of stock options	128		55
Proceeds from initial public offering, net of issuance costs	57,762
Net cash provided by financing activities	57,990	8,416	2,540
Net cash increase (decrease) for the period	40,306	11,240	(2,980)
Cash and cash equivalents at beginning of period	12,357	1,117	4,097
Cash and cash equivalents at end of period	52,663	12,357	1,117
Supplemental disclosure of cash flow information
Cash paid for interest		37	20
Noncash financing activities
Conversion of convertible preferred stock to common stock	65,586
Reclassification of prepaid IPO costs paid in 2013	$ 1,465
Conversion of convertible promissory notes to Series D convertible preferred stock		3,888
Junior Convertible Preferred Stock [Member]
Financing activities
Proceeds from sale of convertible preferred stock			$ 354
Junior A Convertible Preferred Stock [Member]
Financing activities
Proceeds from sale of convertible preferred stock		$ 7,642

Business	12 Months Ended
Business	Dec. 31, 2014
Accounting Policies [Abstract]
Business	1. Business Cara Therapeutics, Inc. (the “Company”) 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. The Company’s registration statement on Form S-1 (File No 333-192230) relating to its initial public offering (“IPO”) was declared effective by the Securities and Exchange Commission on January 30, 2014. The Company registered the offering and sale of 5,750,000 shares of common stock (including 750,000 shares upon exercise of an option by the underwriters) at a public offering price of $11.00 per share for an aggregate offering price of $63,250. As a result of the IPO, the Company received net proceeds of $56,297 after deducting $6,953 of underwriting discounts and commissions and offering expenses paid by the Company. Prior to the IPO, the Company raised several rounds of equity financing and issued debt, resulting in aggregate net proceeds of approximately $73,309, including $7,642 in connection with a Stock Purchase Agreement, which the Company entered into with Maruishi Pharmaceutical Co., Ltd. (“Maruishi”) in April 2013. In addition, in April 2013, the Company entered into a License Agreement with Maruishi, which added $15,000 in cash (see Note 11, Collaborations). As of December 31, 2014, the Company had unrestricted cash and cash equivalents of $52,663 and an accumulated deficit of $80,201. The Company has incurred substantial losses and negative cash flows from operations in nearly every fiscal period since inception, and expects operating losses and negative cash flows to continue into the foreseeable future. The Company recognized net loss available to common stockholders of $17,745 and had net cash flows used in operating activities of $17,642 for the year ended December 31, 2014. The Company expects that cash and cash equivalents at December 31, 2014 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 (“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.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2014

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Use of Estimates

The preparation of financial statements in conformity with generally-accepted accounting principles in the United States (“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.

Fair Value Measurements

The Company’s financial instruments consist of cash and cash equivalents, restricted cash, accounts payable and accrued liabilities. The carrying amount of each of those financial instruments is generally considered to be representative of their respective fair values because of the short-term nature of those instruments.

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 December 31, 2014 and 2013 and by level within the fair value hierarchy:


	December 31, 2014		December 31, 2013
	Level 1		Level 1
Financial assets
Cash equivalents:
Money market savings account and checking account	$	52,663	$	12,357
Restricted cash:
Bank Certificate of Deposit		700		700

Total	$	53,363	$	13,057

The following table represents a rollforward of the fair value of Level 3 instruments (significant unobservable inputs):


	Year Ended December 31, 2013
Liabilities
Balance at beginning of period	$	76
Amounts acquired or issued		—
Net (gains) losses (realized and unrealized)		(76	)
Net settlements		—

Balance at end of period	$	—

The balance at January 1, 2013 includes (1) the fair value of the contingent call option liability related to the convertible promissory notes ($41) (see Note 7, Convertible Promissory Notes) and (2) the fair value of the liability under the Glasgow License Agreement ($35) (see Note 14, License and Research Agreement). The gain related to the convertible promissory notes was recognized as an offset to interest expense and the gain related to the Glasgow License Agreement was recognized as an offset to R&D expense.

Cash and Cash Equivalents

The Company considers all highly liquid investments with an original maturity of three months or less when purchased to be cash equivalents. The carrying amount of cash and cash equivalents approximates its fair value due to its short-term nature.

Concentration of Credit Risk

Financial instruments, which potentially subject the Company to significant concentration of credit risk, consist primarily of cash and cash equivalents. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and management believes that the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which those deposits are held.

Reclassifications

Certain revenue within the Statement of Operations has been reclassified from Collaborative revenue to Clinical compound revenue to conform to the current year presentation.

Property and Equipment

Property and equipment (consisting of computer, office and laboratory equipment, furniture and fixtures, software and leasehold improvements) are stated at cost, net of accumulated depreciation and amortization of leasehold improvements. Depreciation and amortization are calculated using the straight-line method over the estimated useful lives of the respective assets. Leasehold improvements are amortized over the lesser of their useful lives or the life of the lease.


Asset Category	Useful Lives
Computer and office equipment		5 years
Laboratory equipment		8 years
Furniture and fixtures		7 years
Software		3 years
Leasehold improvements		10 years

Long-Lived Assets

ASC 360, Property, Plant and Equipment, addresses the financial accounting and reporting for impairment or disposal of long-lived assets. The Company reviews the recorded values of long-lived assets for impairment whenever events or changes in business circumstances indicate that the carrying amount of an asset or group of assets may not be fully recoverable.

Common Stock and Convertible Preferred Stock Valuation

Due to the absence of an active market for the Company’s common stock and convertible preferred stock prior to its IPO, the Company utilized methodologies in accordance with the framework of the American Institute of Certified Public Accountants Technical Practice Aid, Valuation of Privately-Held Company Equity Securities Issued as Compensation (the “Practice Aid”) to estimate the fair value of its common stock and convertible preferred stock at various reporting dates and in conjunction with various transactions. Each valuation included estimates and assumptions that required the Company’s judgment. These estimates included assumptions regarding future performance, including the probability of successful completion of preclinical studies and clinical trials and FDA approval of product candidates containing CR845, and the probability and estimated time to complete financing and collaborative transactions. Significant changes to the key assumptions used in the valuations could have resulted in different fair values of common stock and convertible preferred stock at each valuation date.

Revenue Recognition

In general, the Company recognizes revenue when all of the following criteria are met: persuasive evidence of an arrangement exists; the Company’s price to the customer is fixed or determinable; collectability is reasonably assured and delivery has occurred or services have been rendered.

The Company has entered into license agreements to develop, manufacture and commercialize drug products. The terms of these agreements typically contain multiple elements, including licenses and research and development services. Payments to the Company under these agreements may include nonrefundable license fees, payments for research activities, payments based upon the achievement of certain milestones and royalties on any resulting net product sales. There are no performance, cancellation, termination or refund provisions in any of the arrangements that contain material financial consequences to the Company.

The Company records revenue related to these agreements in accordance with ASC 605-25, Revenue Recognition Multiple-Element Arrangements. In order to account for these agreements, the Company identifies the deliverables included within an arrangement and evaluates which deliverables represent separate units of accounting based on whether certain criteria are met, including whether the delivered element has stand-alone value to the counterparty. The consideration received is then allocated among the separate units of accounting based on each unit’s relative selling price. The identification of individual elements in a multiple-element arrangement and the estimation of the selling price of each element involves significant judgment, including evaluation as to whether each delivered element has standalone value.

The Company determines the estimated selling price for deliverables within each agreement using vendor specific objective evidence (“VSOE”) of selling price, if available, or third party evidence (“TPE”) of selling price if VSOE is not available, or the Company’s best estimate of selling price, if neither VSOE nor TPE is available. Determining the best estimate of selling price for a deliverable requires significant judgment. Because the Company does not have VSOE or third party evidence of selling price to determine the estimated selling price of a license to its proprietary technology, it typically uses its best estimate of a selling price to estimate the selling prices for licenses to its proprietary technology. In making these estimates, the Company considers market conditions and entity-specific factors, including those contemplated in negotiating the agreements, as well as internally developed estimates that include assumptions related to the market opportunity, estimated development costs, probability of success and the time needed to commercialize a product candidate pursuant to the license. In validating its best estimate of selling price, the Company evaluates whether changes in the key assumptions used to determine its best estimate of selling price will have a significant effect on the allocation of arrangement consideration between deliverables. The Company recognizes consideration allocated to an individual element when all other revenue recognition criteria are met for that element.

Arrangement consideration allocated to license deliverables that represent separate units of accounting is recognized as revenue at the outset of the agreement assuming the general criteria for revenue recognition noted above have been met. Arrangement consideration allocated to license deliverables which do not represent separate units of accounting is deferred. The Company has determined that its license deliverables represent separate units of accounting because the counterparty has the right to sublicense and manufacture in its territory, as defined.

Arrangement consideration allocated to research and development services which represent separate units of accounting is recognized as the services are performed, assuming the general criteria for revenue recognition noted above have been met. The Company has determined that its research and developments services deliverables, as applicable, represent separate units of accounting because similar services are sold separately by other vendors.

The Company’s license agreements include contingent milestone payments related to specified clinical development milestones and regulatory milestones. Development milestones are payable when a product candidate initiates or advances into different clinical trial phases. Regulatory milestones are payable upon submission for marketing approval with the FDA or other countries’ regulatory authorities or on receipt of actual marketing approvals for the compound or for additional indications. At the inception of each agreement that includes milestone payments, the Company evaluates whether each such payment is a milestone payment as defined by ASC 605-28, Revenue Recognition – Milestone Method, because achievement requires performance by the Company and, at inception of the arrangement, there is substantive uncertainty that the event will be achieved, or whether the payment is a contingent payment, because achievement requires performance by the counterparty.

If the payment meets the criteria of a milestone payment, the Company evaluates whether such milestone is considered to be substantive. This evaluation includes an assessment of whether (a) the consideration is commensurate with either (1) the entity’s performance to achieve the milestone, or (2) the enhancement of the value of the delivered item(s) as a result of a specific outcome resulting from the entity’s performance to achieve the milestone, (b) the consideration relates solely to past performance and (c) the consideration is reasonable relative to all of the deliverables and payment terms within the arrangement. The Company evaluates factors such as the scientific, regulatory, commercial and other risks that must be overcome to achieve the respective milestone and the level of effort and investment required to achieve the respective milestone in making this assessment.

The Company recognizes substantive milestone payments as revenue upon the achievement of the milestone, assuming all other revenue recognition criteria are met. If any milestone payment is considered not to be a substantive milestone or is considered to be a contingent payment, the Company initially defers the milestone payment, allocates it to the deliverables based on relative selling price in the same proportion as at inception of the agreement, immediately recognizes revenue to the extent of any delivered elements and recognizes the portion attributable to any undelivered elements over the remaining term of its performance obligations. If no such performance obligations exist, milestones that are considered not to be substantive or are considered to be contingent payments are generally recognized as revenue upon achievement, assuming all other revenue recognition criteria are met.

Royalty revenue is recognized when earned. To date, no royalties have been earned or were otherwise due to the Company.

Research and Development Expenses

Research and development (“R&D”) costs are charged to expense as incurred. Costs incurred under agreements with third parties are charged to expense as incurred in accordance with the specific contractual performance terms of such agreements. Research and development expenses include, among other costs, salaries and other personnel-related costs, costs to conduct clinical trials, costs to manufacture product candidates and clinical supplies, laboratory supplies costs and facility-related costs. Non-refundable research and development advance payments are deferred and capitalized as prepaid R&D expense. The capitalized amounts are expensed as the related goods are delivered or services are performed. As of December 31, 2014 and 2013, the Company recorded $177 and $262 as prepaid R&D expense, respectively.

Income Taxes

The Company accounts for income taxes using the asset and liability method. Under this method, deferred tax assets and liabilities are determined based on differences between the financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. Deferred income tax assets are reduced, as necessary, by a valuation allowance when management determines it is more likely than not that some or all of the tax benefits will not be realized.

The Company applies the provisions of ASC 740, Income Taxes, which prescribes a comprehensive model for how a company should recognize, measure, present and disclose in its financial statements uncertain tax positions that the company has taken or expects to take on a tax return. The financial statements reflect expected future tax consequences of such positions presuming the taxing authorities possess full knowledge of the position and all relevant facts. There were no material uncertain tax positions taken as of December 31, 2014 and December 31, 2013. The Company does not have any interest or penalties accrued related to tax positions as it does not have any unrecognized tax benefits. In the event the Company determines that accrual of interest or penalties are necessary in the future, the amount will be presented as a component of interest expense.

Stock-Based Compensation

The Company grants stock options to employees, non-employee members of the Company’s Board of Directors and non-employee consultants as compensation for services performed. Employee and non-employee members of the Board of Directors’ awards of stock-based compensation are accounted for in accordance with ASC 718, Compensation – Stock Compensation (“ASC 718”). ASC 718 requires all share-based payments to employees and non-employee directors, including grants of stock options, to be recognized in the Statements of Operations based on their grant date fair values. The grant date fair value of stock options is estimated using the Black-Scholes option valuation model.

Using this model, fair value is calculated based on assumptions with respect to (i) the fair value or market price of the Company’s common stock on the grant date; (ii) expected volatility of the Company’s common stock price, (iii) the periods of time over which employees and members of the Company’s Board of Directors are expected to hold their options prior to exercise (expected lives), (iv) expected dividend yield on the Company’s common stock, and (v) risk-free interest rates.

Prior to the effective date of the registration statement related to the Company’s IPO in January 2014, the Company utilized methodologies in accordance with the Practice Aid to determine the fair value of the Company’s common stock on any given date. Subsequently, the stock price input to the Black-Scholes model for each stock option granted is the closing price of the Company’s common stock as quoted on The NASDAQ Global Market on the grant date.

Expected volatility is based on an analysis of guideline companies in accordance with ASC 718. The expected life of stock options granted to employees and members of the Company’s Board of Directors is determined using the average of the vesting period and term, an accepted method for the Company’s option grants under the SEC’s Staff Accounting Bulletin No. 107, Share-Based Payment. The expected dividend yield is zero as the Company has never paid dividends and does not currently anticipate paying any in the foreseeable future. Risk-free interest rates are based on quoted U.S. Treasury rates for securities with maturities approximating the options’ expected lives.

The Company applies a forfeiture rate to the number of unvested awards in each reporting period in order to accrue share-based compensation expense based on an estimate of the number of awards that are expected to vest. Estimated forfeiture rates are based upon historical data of awards that were cancelled prior to vesting. The Company adjusts the total amount of compensation cost recognized for each award, in the period in which each award vests, to reflect the actual forfeitures related to that award. To the extent that the actual forfeiture rate for an award is lower than the estimated forfeiture rate, additional compensation expense is recorded in the period that the award vests. Changes in the Company’s estimated forfeiture rate will result in changes in the rate at which compensation cost for an award is recognized over its vesting period.

The Company accounts for options granted to non-employee consultants under ASC 505-50, Equity-Based Payments to Non-Employees. As such, the Company estimates the fair value of each such option using the Black-Scholes model, with the expected life of stock options granted to non-employees initially equal to the options’ maximum contractual life of ten years, at issuance, and then revalues the option on each reporting date until performance is complete. Under ASC 505-50, upon re-measurement of each award, income or expense is recognized during its vesting term. Compensation cost relating to awards with service-based graded vesting schedules is recognized using the straight-line method.

Income (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. Common stock equivalents include convertible preferred stock, convertible promissory notes and outstanding stock options and stock warrants, which are included under the treasury stock method when dilutive. The computation of diluted net loss per share for each of the years ended December 31, 2012, 2013 and 2014 does not include common stock equivalents since such inclusion would be antidilutive.

During the years ended December 31, 2013 and 2012, the Company computed basic net income (loss) per share available to common stockholders using the “two-class” method, which includes the weighted average number of shares of common stock outstanding during the period and other securities that participate in dividends (a participating security). Prior to the IPO, the Company’s shares of convertible preferred stock were participating securities as defined by ASC 260-10, Earnings Per Share. In conjunction with the closing of the IPO on February 5, 2014, all outstanding shares of convertible preferred stock were automatically converted to shares of the Company’s common stock (see Note 9, Convertible Preferred Stock).

Under the two-class method, basic net income (loss) per share available to common stockholders is computed by dividing the net income (loss) available to common stockholders by the weighted average number of common shares outstanding for the period. The Company allocates net income on a pari passu (equal) basis to both common and preferred stockholders. Net losses are not allocated to preferred stockholders as they do not have an obligation to share in the Company’s net losses. Diluted net income (loss) per share is computed using the more dilutive of (1) the two-class method, or (2) the “if-converted” method.

All calculations of net income (loss) per share, both basic and diluted, reflect the 1-for-2.5 reverse stock split (see Note10, Stockholders’ (Deficit) Equity). Refer to Note 15, Net Loss per Share, for the Company’s calculations of net loss per share available to common stockholders for the periods presented.

Segment Reporting

Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business as one operating segment, which includes all activities related to the discovery and development of novel therapeutics to treat serious medical conditions, including pain and pruritus.

Leases

The Company recognizes rent expense for operating leases on a straight-line basis over the term of the lease, beginning on the date the Company takes possession of the property. Rent expense includes the base amounts stated in the lease agreement as well as the effect of reduced or free rent and rent escalations. At lease inception, the Company determines the lease term by assuming the exercise of those renewal options that are reasonably assured because of the significant economic penalty that exists for not exercising those options. The exercise of renewal options is at the Company’s sole discretion. The expected lease term is one of the factors used to determine whether a lease is classified operating or capital and is used to calculate the straight-line rent expense. The difference between the cash paid to the landlord and the amount recognized as rent expense on a straight-line basis is included in deferred rent and classified within long-term liabilities. Cash reimbursements received from landlords for leasehold improvements and other cash payments received from landlords as lease incentives are recorded as deferred rent and classified as long-term liabilities. Deferred rent related to landlord incentives is amortized using the straight-line method over the lease term as an offset to rent expense. Penalties paid to landlords to terminate a lease before the contractual end date of the lease are recognized on an undiscounted basis in the Statements of Operations.

Litigation Reserves

The Company may become involved in the future in various lawsuits, claims, investigations and proceedings that arise in the ordinary course of business. Accruals are recorded when it is probable that a liability has been incurred and the amount of the liability can be reasonably estimated. The Company reviews these reserves at least quarterly and adjusts these reserves to reflect current law, progress of each case, opinions and views of legal counsel and other advisers, the Company’s experience in similar matters and intended response to the litigation. The Company expenses amounts for administering or litigating claims as incurred. Accruals for legal proceedings, if any, are included in Accounts payable and accrued expenses in the Balance Sheets.

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) (“ASU 2014-09”). ASU 2014-09 provides a single authoritative source of guidance and, thereby, is meant to significantly enhance comparability of revenue recognition practices across entities, industries, jurisdictions, and capital markets. ASU 2014-09 changes the principle under which the Company will recognize revenue from contracts with customers from one which requires the Company to satisfy specific criteria before recognizing revenue to one which requires the Company to recognize revenue in an amount that reflects the consideration to which it expects to be entitled in exchange for the transfer of promised goods or services to customers. The amount of revenue to be recognized in any reporting period is determined by applying the following steps: (1) identify the contract(s) with a customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract and (5) recognize revenue when (or as) the entity satisfies a performance obligation. ASU 2014-09 is effective for the Company for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period (i.e., January 1, 2017). Early application is not permitted. The Company is allowed to adopt ASU 2014-09 either (1) retrospectively to each prior reporting period presented using several practical expedients related to completed contracts and required disclosures, or (2) retrospectively with the cumulative effect of initially applying ASU 2014-09 recognized at the date of initial application, including disclosure of the effect of using this method of adoption on the financial statement line items. The Company is currently in the process of deciding which method of adoption it will use and the effect of adoption of ASU 2014-09 on its results of operations, financial position and cash flows.

In August 2014, the FASB issued Accounting Standards Update 2014-15 Presentation of Financial Statements – Going Concern (Subtopic 205-40), Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (“ASU 2014-15”). ASU 2014-15 codifies, for the first time within GAAP, management’s responsibility to evaluate whether there is substantial doubt about the Company’s ability to continue as a going concern and to provide related footnote disclosures in connection with preparing financial statements for each annual and interim reporting period. Substantial doubt about the Company’s ability to continue as a going concern exists when there are conditions or events, considered in the aggregate, that are known and reasonably knowable at the date that the financial statements are issued, that indicate that the Company will be unable to meet its obligations as they become due within one year after that date. ASU 2014-15 requires the Company to disclose the nature of those conditions or events when they are present, management’s plans to mitigate those conditions or events and whether or not such plans alleviated the substantial doubt. ASU 2014-15 is effective for annual periods ending after December 15, 2016, and interim periods within annual periods beginning after December 15, 2016. Early application is permitted. Prior to adoption of ASU 2014-15, the Company evaluated the need to disclose its ability to continue as a going concern for a reasonable period of time based on projections of its ability to meet its obligations as they become due within a period of one year from the balance sheet date. Upon adoption of ASU 2014-15, that period will be extended to include one year from the date the financial statements are issued and the Company will be required to make the applicable disclosures in its financial statements. The Company does not expect that the adoption of ASU 2014-15 will have a material effect on its financial position, results of operations or cash flows.

Prepaid expenses	12 Months Ended
Prepaid expenses	Dec. 31, 2014
Text Block [Abstract]
Prepaid expenses	3. Prepaid expenses As of December 31, 2014, prepaid expenses was $287, consisting of $92 of prepaid insurance, $177 of prepaid R&D clinical costs and $18 of other costs. As of December 31, 2013, prepaid expenses was $2,140, consisting of $1,833 of IPO costs, $262 of prepaid R&D clinical costs, $34 of prepaid insurance, and $11 of other costs.

Property and Equipment, Net

12 Months Ended

Dec. 31, 2014

Property, Plant and Equipment [Abstract]

Property and Equipment, Net

4. Property and Equipment, Net

Property and equipment, net consists of the following:


	December 31,
	2014		2013
Computer and office equipment	$	309	$	275
Laboratory equipment		233		233
Furniture and fixtures		156		153
Software		126		126
Leasehold improvements		7,453		7,453

	$	8,276	$	8,240
Less accumulated depreciation and amortization		6,192		5,415

Property and equipment, net	$	2,084	$	2,825

Depreciation and amortization expense included in research and development expense and general and administrative expense was $783, $789 and $1,021 for the years ended December 31, 2014, 2013 and 2012, respectively.

During the third quarter of 2012, the Company sold most of its laboratory equipment for net proceeds of $511 resulting in a net loss of $286, included in general and administrative expense.

Restricted Cash	12 Months Ended
Restricted Cash	Dec. 31, 2014
Cash and Cash Equivalents [Abstract]
Restricted Cash	5. Restricted Cash The Company is required to maintain a stand-by letter of credit as security under the Shelton Lease (refer to Note 18, Commitments and Contingencies). The Company’s bank requires the Company to maintain a restricted cash balance equal to the stand-by letter of credit, which is invested in a bank certificate of deposit. The letter of credit balance remains at $700 through the end of the lease term in 2017. As of December 31, 2014 and 2013, the Company has $700 of restricted cash in long-term assets.

- Definition

The entire disclosure for cash and cash equivalent footnotes, which may include the types of deposits and money market instruments, applicable carrying amounts, restricted amounts and compensating balance arrangements. Cash and equivalents include: (1) currency on hand (2) demand deposits with banks or financial institutions (3) other kinds of accounts that have the general characteristics of demand deposits (4) short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments maturing within three months from the date of acquisition qualify.

+ References + Details

Accounts Payable and Accrued Expenses

12 Months Ended

Dec. 31, 2014

Payables and Accruals [Abstract]

Accounts Payable and Accrued Expenses

6. Accounts Payable and Accrued Expenses

Accounts payable and accrued expenses consist of the following:


	December 31,
	2014		2013
Accounts payable	$	515	$	676
Accrued research projects		549		405
Accrued professional fees		266		739
Accrued compensation and benefits		504		83
Accrued other		112		55

	$	1,946	$	1,958

Convertible Promissory Notes	12 Months Ended
Convertible Promissory Notes	Dec. 31, 2014
Debt Disclosure [Abstract]
Convertible Promissory Notes	7. Convertible Promissory Notes In December 2012 and February 2013, the Company issued an aggregate of $4,000 principal amount of Convertible Promissory Notes (“Notes”) due August 28, 2013 (“Maturity Date”). The sale was consummated through two closings. The initial closing was on December 28, 2012 for $2,538 principal amount. The final closing was on February 28, 2013 for $1,462 principal amount. All of the Notes were purchased by current stockholders, all of whom were given the opportunity to buy their pro rata share of the Notes. The holders of preferred stock who did not participate in the Note financing had their shares of preferred stock converted into common stock at their respective then applicable conversion rates. As a result, as of February 2013, 2,246,743 shares of preferred stock were converted into 959,545 shares of common stock. Because the original terms of the preferred stock were modified to reflect this mandatory conversion, the Company determined that the preferred stock had been extinguished. Accordingly, the conversion date difference between the carrying value of the preferred stock converted ($4,466) and the fair value of the common stock issued ($3,575) has been recorded as a gain ($891) within accumulated deficit. The Notes bore interest at 8% per annum and had a Maturity Date of August 28, 2013. The Notes were not eligible to be repaid prior to the maturity date without the consent of the holders of a majority in interest of the outstanding aggregate principal amount of the Notes. The Notes included an optional conversion feature and a mandatory conversion feature. The optional conversion feature allowed the Note holder, any time prior to the Maturity Date, to elect to convert the balance of the note plus accrued interest into Series D convertible preferred stock at a conversion price of $1.444244 per share. In accordance with ASC 470-20, Debt with Conversion and Other Options, the Company determined that the intrinsic value of the beneficial conversion feature embedded in the Notes issued in the initial closing was $2,050, based on the estimated fair value of the Series D convertible preferred stock as of December 31, 2012 of $2.61 per share, and this intrinsic value was recorded as a debt discount, to be accreted to interest expense over the term of the Notes. As of December 31, 2012, the Company amortized $25 of debt discount to interest expense. As of February 28, 2013, the final closing of the Note financing, the Company determined that the intrinsic value of the beneficial conversion feature of the Notes issued in the final closing was $1,382 and recorded this amount as an additional debt discount. For the year ended December 31, 2013, the Company amortized $3,407 of debt discount to interest expense. The mandatory conversion of the Notes would have occurred in the event the Company issued or sold equity securities on or before August 28, 2013 of not less than $10,000. In this event, the Notes plus all accrued interest would have automatically converted into the issued class of equity securities at a price per share equal to 90% of the cash price paid by the investors in the new equity securities. In accordance with ASC 815-15, Derivatives and Hedging, the Company was required to record the embedded mandatory conversion feature as a free-standing financial instrument, as the conversion feature was a substantial contingent call option. The Company recorded $41 as the fair value of the contingent call option liability related to the Notes issued in the initial closing of the Note financing as of December 31, 2012, with a corresponding amount recorded as additional debt discount, with the debt discount to be accreted to interest expense over the life of the Notes. Any increases or decreases to the fair value of the contingent call option would be recorded in operations through the life of the Notes. The Company estimated the fair value of the contingent call option by estimating the accreted value of the Notes upon conversion, with consideration provided for the 10% price discount and the probability of the Company closing an equity offering in excess of $10,000 before August 28, 2013. The Company classified the liability within Level 3 of the fair value hierarchy as the probability factor is an unobservable input and significant to the valuation model. Increases in the probability of an equity offering closing before August 28, 2013 in excess of $10,000 would increase the fair value of the liability. In April 2013, the estimated fair value of the contingent call option of $41 was reduced to zero with an equal reduction in interest expense, since the Company estimated the probability of closing a $10,000 equity offering before August 28, 2013 as zero, following the receipt of $23,000 in connection with the Maruishi transaction in April 2013, which removed the need for a $10,000 financing prior to August 28, 2013. Prior to the Maturity Date, the Company received notice from Note holders to convert Notes in the aggregate amount of $3,888 in principal plus accrued interest, into 2,692,291 shares of Series D convertible preferred stock, and the remaining Notes, in the aggregate amount of $311 in principal and accrued interest, were repaid during October 2013. Deferred financing costs related to the convertible promissory notes were amortized over the life of the related debt using the effective interest method. For the years ended December 31, 2013 and 2012, deferred financing costs of $117, and $4, respectively, were amortized and included in interest expense.

Long-Term Debt	12 Months Ended
Long-Term Debt	Dec. 31, 2014
Debt Disclosure [Abstract]
Long-Term Debt	8. Long-Term Debt In September 2007, the Company entered into a $4,000 term loan (“Loan”) with Connecticut Innovations Inc. (“CII”). The Loan carried a 7% interest rate and was payable in monthly installments over five years. The Loan was collateralized by property and equipment which was owned by the Company that was located in Shelton, Connecticut. The CII Loan contained certain non-financial covenants, including the requirement that the Company maintain its principal place of business and conduct the majority of its operations in Connecticut. If the Company failed to maintain its Connecticut presence, all amounts due under the Loan would be immediately due and payable with the cumulative interest rate increasing to 25%. On September 4, 2012, the Company and CII amended the Loan to defer all payments due between July 1, 2012 and December 31, 2012 until January 2, 2013 and to increase the interest rate to 8.5%. The Company repaid the remaining principal balance of $307 plus accrued interest outstanding under the Loan in April 2013. In connection with the Loan, the Company issued to CII a warrant to purchase 19,851 shares of common stock at an exercise price of $10.08. The fair value of such warrant at the date of issuance was determined not to be material. The warrant also incorporated the non-financial covenants of the Loan described above. If the Company failed to maintain its Connecticut presence, it would be required to pay CII the excess of the market price of the common stock over the warrant exercise price for all unexercised shares represented by the warrant and/or the exercise price paid plus the market price on any shares acquired through a previous exercise of the warrants. On July 31, 2014, CII exercised its outstanding warrant in a cashless exercise, resulting in the issuance of 6,383 shares of the Company’s common stock.

Convertible Preferred Stock

12 Months Ended

Dec. 31, 2014

Text Block [Abstract]

Convertible Preferred Stock

9. Convertible Preferred Stock

In May 2012, the Company issued to Chong Kun Dang Pharmaceutical Corporation (“CKD”) 173,611 shares of Junior convertible preferred stock, $0.001 par value per share (“Junior Preferred Stock”) having an estimated fair value of $354. The shares were sold as part of the license transaction with CKD (refer to Note 11, Collaborations).

In connection with the Notes (refer to Note 7, Convertible Promissory Notes), as of February 2013, the holders of 2,246,743 shares of preferred stock who did not participate in the Note financing had their shares of preferred stock converted into 959,545 shares of common stock.

In April 2013, the Company issued to Maruishi (refer to Note, 11 Collaborations) 2,105,263 shares of Junior A convertible preferred stock (“Junior A Preferred Stock”), having an estimated fair value of $7,663. The shares were sold as part of the license transaction with Maruishi.

In September 2013, the Company issued an aggregate of 2,692,291 shares of Series D convertible preferred stock upon the conversion of the Notes (refer to Note 7, Convertible Promissory Notes). Each series of convertible preferred stock is referred to as that series’ Preferred Stock. All series of convertible stock are, collectively, referred to as Preferred Stock. The following tables summarize the outstanding Preferred Stock as of December 31, 2013 and December 31, 2012:

As of December 31, 2013


	Preferred Shares Authorized		Preferred Shares Issued and Outstanding		Liquidation Preference		Carrying Value		Common Stock Issuable Upon Conversion
Junior		173,611		173,611	$	500	$	354		69,444
Junior A		2,105,263		2,105,263		8,000		7,642		842,105
Series A		1,677,118		1,677,118		1,677		1,677		670,830
Series B		2,254,417		2,254,417		4,509		4,509		980,163
Series C		10,930,946		10,930,946		33,886		33,886		5,173,413
Series D		12,260,845		12,045,574		17,397		17,518		4,818,216

		29,402,200		29,186,929	$	65,969	$	65,586		12,554,171

As of December 31, 2012


	Preferred Shares Authorized		Preferred Shares Issued and Outstanding		Liquidation Preference		Carrying Value		Common Stock Issuable Upon Conversion
Junior		173,611		173,611	$	500	$	354		69,444
Junior A		—		—		—		—		—
Series A		2,000,000		2,000,000		2,000		2,000		800,000
Series B		2,370,000		2,370,000		4,740		4,740		1,030,434
Series C		11,706,450		11,706,450		36,290		36,290		5,540,457
Series D		10,386,057		10,386,057		15,000		15,138		4,154,422

		26,636,118		26,636,118	$	58,530	$	58,522		11,594,757

Upon the closing of the Company’s IPO on February 5, 2014, all 29,186,929 shares of the Company’s Preferred Stock that were issued and outstanding on that date were automatically converted into an aggregate of 12,554,171 shares of its common stock. As of December 31, 2014, there were no shares of Preferred Stock authorized or outstanding.

Prior to automatic conversion of the Preferred Stock to common stock upon the closing of the Company’s IPO, the following terms and conditions applied to the Preferred Stock:

Liquidation Preferences

In the event of any voluntary or involuntary liquidation, dissolution, or winding up of the Company, including a deemed liquidation event, as defined in the Company’s amended and restated certificate of incorporation, the following liquidation preferences as of December 31, 2013 were payable to the holders of Preferred Stock: Series D Preferred Stock, aggregate liquidation preference of $17,397, plus declared, but unpaid dividends; Series C Preferred Stock, aggregate liquidation preference of $33,886, plus declared, but unpaid dividends; Series B Preferred Stock, aggregate liquidation preference of $4,509, plus declared, but unpaid dividends; Series A Preferred Stock, aggregate liquidation preference of $1,677 plus declared, but unpaid dividends; Junior A Preferred Stock, aggregate liquidation preference of $8,000 plus declared, but unpaid dividends; and Junior Preferred Stock, aggregate liquidation preference of $500 plus declared, but unpaid dividends. The Series D Preferred Stock liquidation preferences are senior to Series C Preferred Stock liquidation preferences, the Series C Preferred Stock liquidation preferences are senior to the Series B Preferred Stock liquidation preferences, the Series B Preferred Stock liquidation preferences are senior to the Series A Preferred Stock liquidation preferences, the Series A Preferred Stock liquidation preferences are senior to the Junior A Preferred Stock liquidation preferences, and the Junior A Preferred Stock liquidation preferences are senior to the Junior Preferred Stock liquidation preferences. If all amounts would have been paid to the holders of the Preferred Stock in respect of their liquidation preferences, then the remaining assets of the Company would have been distributed pro rata to the holders of Series D Preferred Stock and the common stockholders, subject to a maximum of an additional $4.332732 per share for the holders of Series D Preferred Stock. As a result, the Series D Preferred Stock’s total liquidation preference could have been up to $70,000, exclusive of any declared, but unpaid dividends.

The amount that each holder of Preferred Stock would have received upon liquidation, dissolution or winding up of the Company would have been the greater of the cumulative amounts described above or the amount that such holder of Preferred Stock would have received if the shares of Preferred Stock converted into common stock immediately prior to the liquidation, dissolution or winding up of the Company.

As of December 31, 2013, since the Preferred Stock may have become redeemable upon an event that was outside of the control of the Company, the Preferred Stock was classified outside of permanent equity.

Conversion

Each holder of Preferred Stock had the right to convert any or all of such holder’s Preferred Stock into common stock at any time. As of December 31, 2013, Junior Preferred Stock, Junior A Preferred Stock, Series A Preferred Stock and Series D Preferred Stock were convertible into common stock at a conversion ratio of one to 0.4 and Series B and Series C were convertible into common stock at a conversion ratio of one to 0.434782 and one to 0.473282, respectively. The conversion ratio for all Preferred Stock was subject to adjustment based on certain events specified in the Company’s amended and restated certificate of incorporation, including a stock split, if the Company pays a dividend to common stockholders without a corresponding dividend to the Preferred Stockholders or if the Company sells, or is deemed to sell, common stock at a price per share that is less than the then effective conversion prices of each class of Preferred Stock. Pursuant to these provisions, the conversion ratio for the Series B Preferred Stock and Series C Preferred Stock was adjusted upon the issuance of the Series D Preferred Stock.

Automatic Conversion

Contemporaneously with the closing of a qualified public offering of common stock, as defined in the Company’s amended and restated certificate of incorporation, or upon a vote of the holders of a majority of the Preferred Stock, voting together as a single class, and holders of at least 67% of the Series D Preferred Stock, all outstanding shares of Preferred Stock would automatically convert into common stock at the then effective applicable conversion rates for such shares. Contemporaneously with the closing of the Company’s IPO, all outstanding shares of Preferred Stock were automatically converted into common stock at the then effective applicable conversion rates for such shares (see above).

Dividends

Dividends on all series of outstanding Preferred Stock were payable when and if declared by the Company’s Board of Directors. No dividends shall be paid to the holders of the Company’s common stock unless equivalent dividends have been declared and paid on each series of outstanding Preferred Stock. Through December 31, 2014, no dividends were declared or paid by the Company.

Voting Rights

As set forth in the Company’s amended and restated certificate of incorporation, the holders of Series A, Series B, Series C and Series D Preferred Stock (“Senior Preferred Stock”) were entitled to vote as one class, with common stockholders, based on the number of shares of common stock each holder would receive upon conversion of their Senior Preferred Stock into shares of common stock, for all matters except for the approval of certain major actions by the Company and the election of directors. Subject to certain ownership thresholds and certain nomination and approval rights set forth in the Company’s amended and restated certificate of incorporation and an amended and restated voting agreement by and among the Company and certain stockholders of the Company, directors are elected as follows: common stockholders vote as a separate class for the election of two directors; the holders of Series D Preferred Stock vote as a separate class for the election of one director; the holders of Series C Preferred Stock vote as a separate class for the election of three directors; and the holders of Senior Preferred Stock vote as a combined class for the election of one director. Upon the closing of the Company’s initial public offering on February 5, 2014, the voting agreement terminated and the Company’s stockholders no longer have any special rights regarding the election or designation of members of its Board of Directors.

Registration Rights

The holders of shares of Preferred Stock have certain registration rights as set forth in an amended and restated investors’ rights agreement by and among the Company and certain of its stockholders.

Stockholders' (Deficit) Equity

12 Months Ended

Dec. 31, 2014

Equity [Abstract]

Stockholders' (Deficit) Equity

10. Stockholders’ (Deficit) Equity

On January 16, 2014, the Company’s Board of Directors approved an Amended and Restated Certificate of Incorporation, which, among other things, increased the authorized number of shares of the Company’s common stock, par value $0.001 per share, from 50,000,000 to 100,000,000 and authorized 5,000,000 shares of undesignated preferred stock, par value $0.001 per share, that may be issued from time to time by the Board of Directors of the Company in one or more series. As of December 31, 2014, there were 22,802,039 shares of common stock and no shares of preferred stock issued and outstanding.

The Company’s Board of Directors and stockholders approved a 1-for-2.5 reverse stock split of the Company’s common stock effective on January 16, 2014, which resulted in an adjustment to the preferred stock conversion price to reflect a proportional decrease in the number of shares of common stock to be issued upon conversion. All share and per share amounts in the financial statements and notes thereto in this Annual Report on Form 10-K have been retroactively adjusted for all periods presented to give effect to this reverse stock split.

On January 30, 2014, the Company’s registration statement on Form S-1 relating to its IPO was declared effective, providing for the sale of 5,750,000 shares of the Company’s common stock at a public offering price of $11.00 per share (see Note 1, Business).

On December 1, 2014, the Company sold 11,442 shares of common stock to its Chief Medical Officer at $8.74 per share (which was the closing price of the Company’s common stock on the NASDAQ Global Market on that date) for gross proceeds of $100. The shares of common stock have not been registered under the Securities Act of 1933, as amended (the “Securities Act”), and have been sold pursuant to an exemption from registration contained in the Securities Act based in part upon the purchaser’s representations contained in the purchase agreement.

The following table summarizes common stock reserved for conversion of Preferred Stock and the exercise of warrants and options at December 31, 2014 and 2013. On February 5, 2014, all shares of Preferred Stock automatically converted to shares of common stock (see Note 9, Convertible Preferred Stock). On July 31, 2014, all outstanding warrants were exercised (see Note 8, Long Term Debt).


	December 31,
	2014		2013
Conversion of Series A convertible preferred		—		670,830
Conversion of Series B convertible preferred		—		901,757
Conversion of Series C convertible preferred		—		4,372,369
Conversion of Series D convertible preferred		—		4,818,216
Conversion of Junior convertible preferred		—		69,444
Conversion of Junior A convertible preferred		—		842,105
Series B and C anti-dilution shares		—		879,450
Exercise of warrant		—		19,851
Exercise of stock options		1,898,360		1,247,959

		1,898,360		13,821,981

Each share of common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. Common stockholders are entitled to dividends when and if declared by the Board of Directors, subject to the preferential rights of the holders of preferred stock, if any.

As described in Note 2, Summary of Significant Accounting Policies – Common Stock and Convertible Preferred Stock Valuation, prior to its IPO, the Company utilized methodologies in accordance with the Practice Aid to support the fair value of its common stock at key points in time. In conducting these valuations, the Company considered all objective and subjective factors that it believed to be relevant for each valuation conducted, including its best estimate of its business condition, prospects and operating performance at each valuation date.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(d),(e))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21484-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 4.E)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 5
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+ Details

Collaborations	12 Months Ended
Collaborations	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Collaborations	11. Collaborations Chong Kun Dang Pharmaceutical Corporation In April, 2012, the Company entered into a license agreement with Chong Kun Dang Pharmaceutical Corporation (“CKD”) that provides CKD with the exclusive rights to develop, manufacture and commercialize products containing CR845, the Company’s lead product candidate, in South Korea. Under the agreement, the Company received a non-refundable and non-creditable amount of $1,000 and 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. At the time of execution of this license 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 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 milestones also relate solely to past performance and monetary investment of the Company to achieve the clinical advancement. In exchange for the $1,000, the Company provided CKD with the license for CR845 and issued CKD 173,611 shares of Junior Preferred Stock. The Company recorded the issuance of the 173,611 shares of Junior Preferred Stock as a capital transaction for $354, which represented the shares’ estimated fair value as of the transaction date. The remaining proceeds of $646 were recorded as license revenue as the license was the only deliverable within the agreement that had stand-alone value and was determined to be a separate unit of accounting under ASC 605-25, Revenue Recognition Multiple – Element Arrangements. In addition, the Company received milestone payments of $750 during the year ended December 31, 2012 related to the Company’s achievement of U.S. clinical development milestones stated in the CKD license agreement. The next potential milestone that the Company could be entitled to receive under the CKD license agreement will be a clinical development milestone for the completion of a Phase 1b clinical trial in the U.S. for a certain indication. If achieved, this milestone will result in a $250 payment being due to the Company. During the year ended December 31, 2012, the Company recorded license and milestone revenue related to the CKD license agreement of $1,190, net of South Korean withholding tax of $206. Maruishi Pharmaceutical Co., Ltd. In April 2013, the Company entered into a license agreement with Maruishi under which the Company granted Maruishi an exclusive license to develop, manufacture, and commercialize products containing CR845 for acute pain and uremic pruritus in Japan. The Company and Maruishi are each responsible to use commercially reasonable efforts, at its expense, to develop, obtain regulatory approval for and commercialize CR845 in the United States and Japan, respectively. In addition, the Company will provide Maruishi specific clinical development services for CR845 used in Maruishi’s field of use. Under the terms of the agreement, the Company received an upfront non-refundable, non-creditable license fee of $15,000. As indicated in Note 2, Summary of Significant Accounting Policies – Revenue Recognition, the Company accounts for arrangements of this type under ASC 605-25, Revenue Recognition—Multiple Element Arrangements. The Company has identified two deliverables under this guidance: (1) the license; and (2) the R&D services specific to the uremic pruritus field of use. The Company has determined that the license has standalone value because Maruishi has the right to sublicense and manufacture CR845 in Japan. The second deliverable is the R&D services, which also have standalone value as similar services are sold separately by other vendors. Since both license and R&D services separability criteria have been met, they are being accounted for as separate units of accounting at the outset of the arrangement. As a result, the total value of the arrangement of $15,337 (consisting of the $15,000 upfront payment, plus the additional amount assigned to these deliverables as a result of the Junior A Preferred Stock premium, see below) was allocated between the two units of accounting. The Company used its best estimate of the selling price of these units of accounting, since, as described in Note 2 Summary of Significant Accounting Policies – Revenue Recognition, neither VSOE nor TPE was available. To determine these estimates, the Company used a discounted cash flow method that forecasted and analyzed CR845 in the Japanese market, the phase of clinical development as well as considering recent similar license arrangements within the same phase of clinical development, therapeutic area, type of agreement, etc. As a result, at inception of this license agreement, the management of the Company determined that the license and the R&D services had estimated selling prices of $10,200 and $6,200, respectively. The resulting percentage allocations were applied to the $15,337 of total consideration, which resulted in $9,637 being assigned to the license unit of accounting, which was recognized immediately as license revenue, while $5,700 was assigned to the R&D services unit of accounting. The amount assigned to the R&D services unit of accounting was initially recorded as deferred revenue and is being recognized as revenue as the services are provided. Upon achievement of a milestone by Maruishi during June 2014, the Company deferred a portion of the milestone payment (see below). 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 U.S. The Company accounts for any future milestone payments under ASC 605-28 Revenue Recognition – Milestone Method (see Note 2, Summary of Significant Accounting Policies). At the time of execution of this license 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 U.S. 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. However, the milestones achieved by Maruishi in Japan are not substantive and will be accounted for as contingent consideration. During June 2014, Maruishi completed a Phase 1 clinical trial in Japan related to CR845 in acute post-operative pain, which constituted achievement of one of the milestones specified in the license agreement. As the milestone was considered not to be substantive, the payment was accounted for as contingent consideration. Accordingly, the Company allocated the non-refundable contingent payment of $480, net of a contractual foreign currency exchange adjustment, to the two deliverables in the same proportion as the initial upfront payment had been allocated. The portion of the contingent payment allocated to the previously delivered license deliverable ($302) was recognized as license revenue entirely at the time of achievement of the milestone. A portion of the contingent payment allocated to the R&D services deliverable ($88) was recognized as collaborative revenue at the time of achievement of the milestone to the extent of R&D services provided through that date and the remainder ($90) was deferred and is being recognized as collaborative revenue through the period during which the Company provides R&D services to Maruishi. The next potential milestone that the Company could be entitled to receive under the Maruishi license agreement will be a clinical development milestone for the initiation of a Phase 1 clinical trial in Japan for a certain indication. If achieved, this milestone will result in a $2,000 payment being due to the Company. Along with the R&D services performed by the Company for Maruishi, the Company supplies 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 are capitalized as prepaid expense. During the manufacturing process, title and risk of loss remains with the third party until the Company has paid in full for the material. Once the Company has title to the CR845 and has delivered it to Maruishi, prepaid expense related to that CR845 is reduced with an offset to R&D expense. At that time, Maruishi reimburses the Company for its external and internal costs for purchasing CR845 and processing the sale to Maruishi and the Company recognizes clinical compound revenue for the reimbursement amount. Deposits received from Maruishi prior to delivery of CR845 are recorded as deferred revenue. The Company is also eligible to receive tiered, low double digit royalties with respect to any sales of the licensed product sold in Japan by Maruishi. Additionally, the Company can receive sublicense fees (subject to certain credits for milestone payments already made) if Maruishi enters into a sublicense agreement regarding the product candidates. Also, in conjunction with entering into this arrangement, Maruishi purchased 2,105,263 shares of Junior A Preferred Stock of the Company pursuant to a stock purchase agreement for a purchase price of $3.80 per share, for total consideration of $8,000. These shares have been recorded at their fair value of $7,663 or $3.64 per share. As a result, the premium of $337 was allocated to the arrangement consideration (see above). As of December 31, 2014 and 2013, the Company had $1,452 and $3,475, respectively, of deferred revenue pursuant to the R&D services deliverable under the license agreement with Maruishi. During the years ended December 31, 2014 and 2013, the Company recognized $302 and $9,637, respectively, of license fee revenue, $2,201 and $2,225, respectively, of collaborative revenue from the amortization of deferred revenue arising from the portion of the upfront payment received pursuant to the license agreement with Maruishi that was allocated to the R&D services deliverable and $674 and $102, respectively, from the sale of CR845 clinical compound. The Company incurred R&D expense related to the Maruishi license agreement of $3,558 (consisting of $3,000 of clinical trial costs related to the R&D services deliverable and $558 related to cost of clinical compound sold to Maruishi) and $2,452 (consisting of $2,420 of clinical trial costs related to the R&D services deliverable and $32 related to cost of clinical compound sold to Maruishi) during years ended December 31, 2014 and 2013, respectively.

Stock-Based Compensation

12 Months Ended

Dec. 31, 2014

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation

12. Stock-Based Compensation

2014 Equity Incentive Plan

The Company’s Board of Directors adopted, and its stockholders subsequently approved, its 2014 Equity Incentive Plan, or 2014 Plan, in January 2014. The 2014 Plan became effective immediately upon the signing of the underwriting agreement for the Company’s IPO. 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 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 non-employee 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 been 25% on the first anniversary of the date of grant and the balance ratably over the next 36 months. The Plan Administrator determines the term of Stock Awards granted under the 2014 Plan up to a maximum of ten years.

Initially, the aggregate number of shares of the Company’s common stock that may be issued pursuant to Stock Awards under the 2014 Plan is 1,600,000 shares. Additionally, the 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. 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. 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 to 2,284,061.

2004 Stock Incentive Plan

The Company’s 2004 Stock Incentive Plan (the “2004 Plan”), as amended, was adopted by the Company’s Board of Directors and stockholders. Under the 2004 Plan, the Company has granted stock options to selected officers, employees and consultants of the Company. The Company’s Board of Directors administers the 2004 Plan. Options granted under the 2004 Plan have a maximum term of ten years. Options issued generally vest 25% on the first anniversary date of grant and the balance ratably over the next 36 months. Although as of December 31 2013, 757,799 shares remained available for future issuance pursuant to the grant of options or restricted share awards under the 2004 Plan, following the effectiveness of the 2014 Plan in January 2014, no additional options or restricted share awards were granted under the 2004 Plan. As of September 30, 2014, the 2004 Plan has expired and no further grants of stock options or restricted stock are allowed.

The Company accounts for stock options granted to employees and non-employee members of the Board of Directors in accordance with ASC 718, Compensation – Stock Compensation. The Company also occasionally grants stock options to non-employee consultants. Such grants are accounted for pursuant to ASC 505-50, Equity-Based Payments to Non-Employees (refer to Note 2, Summary of Significant Accounting Policies – Stock-Based Compensation).

A summary of the Company’s stock option activity related to employees, non-employee members of the Board of Directors and non-employee consultants as of December 31, 2014 and changes during the year then ended is as follows:


	Number of Options			Weighted- Average Exercise Price		Aggregate Intrinsic Value
Outstanding at December 31, 2013		490,160		$	1.34
Granted		884,000			11.24
Exercised		(191,800	)		0.67
Forfeited		(160,000	)		13.26

Outstanding at December 31, 2014		1,022,360		$	8.16	$	2,763

Weighted average remaining contractual life as of December 31, 2014 (yrs)		7.78

Options exercisable at December 31, 2014		299,735		$	2.11	$	2,366

Weighted average remaining contractual life as of December 31, 2014 (yrs)		3.90

Options vested and expected to vest at December 31, 2014		990,191		$	8.05	$	2,743

Weighted average remaining contractual life as of December 31, 2014 (yrs)		7.73

The total fair value of options vested during the years ended December 31, 2014, 2013 and 2012 was $393 and $75 and $65, respectively. The intrinsic value of options exercised during the years ended December 31, 2014, 2013 and 2012 was $2,055, $0 and $10, respectively.

During the years ended December 31, 2013 and 2012, the Company did not grant any stock options to employees, non-employee members of the Board of Directors or non-employee consultants. The fair values of the stock options granted to those groups during the year ended December 31, 2014 were estimated using the Black-Scholes option valuation model with the following ranges of assumptions (see Note 2, Summary of Significant Accounting Policies – Stock-Based Compensation):


		Year Ended December 31, 2014
Risk-free interest rate		1.64% – 2.72%
Expected volatility		64.9% – 71.3%
Expected dividend yield		0%
Expected life of employee and Board of Directors’ options (in years)		6.25
Expected life of non-employee options (in years)		10

The weighted average grant date fair value of options granted to employees, non-employee members of the Board of Directors for their Board service and non-employee consultants during the year ended December 31, 2014 was $7.09.

At the end of each fiscal quarter during the years ended December 31, 2014, 2013 and 2012, the Company used the Black-Scholes option valuation model with the following ranges of assumptions to re-measure the fair value of all outstanding vested options that had been granted to non-employee consultants until each option grant was fully vested.


	Year Ended December 31,
	2014	2013	2012
Risk-free interest rate	1.96% – 2.72%	2.5% – 3.2%	1.77%
Expected volatility	69% – 71%	71% – 72%	73%
Expected dividend yield	0%	0%	0%
Expected life of non-employee options (in years)	6 – 10	1.5 – 7	2 – 8

Under ASC 505-50, upon re-measurement of each award, income or expense is recognized during its vesting term.

The weighted average fair values of outstanding vested options that had been granted to non-employee consultants as re-measured during the years ended December 31, 2014, 2013 and 2012 were $10.77, $6.54 and $1.77, respectively.

During the years ended December 31, 2014, 2013 and 2012, the Company recognized compensation expense in the accompanying Statements of Operations relating to stock options, as follows:


	Year Ended December 31,
	2014		2013		2012
Research and development	$	349	$	71	$	48
General and administrative		1,022		52		13

Total stock option expense	$	1,371	$	123	$	61

As of December 31, 2014, the total compensation expense relating to unvested options granted to employees, non-employee members of the Board of Directors and non-employee consultants that had not yet been recognized was $3,768, which is expected to be realized over a weighted average period of 3.24 years. The Company will issue shares upon exercise of options from common stock reserved.

Income Taxes

12 Months Ended

Dec. 31, 2014

Income Tax Disclosure [Abstract]

Income Taxes

13. Income Taxes

The Company’s benefit from income taxes is as follows:


	December 31,
	2014			2013			2012
Current:
Federal	$	—		$	—		$	—
State		(201	)		(30	)		(31	)

		(201	)		(30	)		(31	)

Deferred:
Federal		—			—			—
State		—			—			—

		—			—			—

Benefit from income taxes	$	(201	)	$	(30	)	$	(31	)

The Company’s tax benefits relate to state research and development tax credits exchanged for cash. The State of Connecticut provides companies with the opportunity to exchange certain research and development credit carryforwards for cash in exchange for foregoing the carryforward of the research and development credit. The program provides for such exchange of the research and development credits at a rate of 65% of the annual research and development credit, as defined.

A reconciliation of income taxes computed using the U.S. federal statutory rate to that reflected in operations is as follows:


	December 31,
	2014			2013			2012
Income taxes using U.S. federal statutory rate		34.00	%		34.00	%		34.00	%
State income taxes, net of federal benefit		5.23	%		6.03	%		5.60	%
Impact of R&D tax credit on effective tax rate		3.03	%		12.04	%		0.00	%
Impact of foreign tax credit on effective tax rate		0.00	%		0.00	%		3.27	%
Stock option shortfalls and cancellations		-0.69	%		0.00	%		-2.54	%
Provision to return adjustments		-0.57	%		-1.42	%		-1.95	%
Change in valuation allowance		-39.88	%		-49.90	%		-37.89	%

		1.12	%		0.75	%		0.49	%

Significant components of the Company’s deferred tax assets are as follows:


	December 31,
	2014			2013
Net operating loss carryforwards	$	27,094		$	21,433
Federal and state tax credits		3,508			2,947
Accelerated depreciation		1,018			860
Deferred revenue		566			—
Stock-based compensation expense		333			85
Rent expense		114			136
Amortization of R&D intangible assets		56			67
Accrued vacation		27			32

		32,716			25,560
Valuation allowance		(32,716	)		(25,560	)

Net deferred tax asset	$	—		$	—

A 100% valuation allowance has been recorded on the deferred tax asset as of December 31, 2014 and 2013 because management believes it is more likely than not that the asset will not be realized. The change in the valuation allowance during 2014 and 2013 was $7,156 and $667, respectively.

The Company has a tax benefit of approximately $401 related to the exercise of non-qualified stock options and the disqualified disposition of incentive stock options. Pursuant to ASC 718, the benefit will be recognized and recorded to additional paid-in-capital when the benefit is realized through the reduction of taxes payable.

The Company applies the provisions of ASC 740, Income Taxes, which prescribes a comprehensive model for how a company should recognize, measure, present, and disclose in its financial statements uncertain tax positions that the company has taken or expects to take on a tax return. The financial statements reflect expected future tax consequences of such positions presuming the taxing authorities possess full knowledge of the position and all relevant facts. As of December 31, 2014 and 2013, the Company had no unrecognized tax benefits or related interest and penalties accrued. In the event the Company determines that accrual of interest or penalties are necessary in the future, the amount will be presented as a component of interest expense.

At December 31, 2014, the Company had federal and state net operating loss carryforwards of approximately $71,369 and $65,260 respectively. The federal and state tax loss carryforwards will begin to expire in 2026 and 2027, respectively, unless previously utilized. The losses may also be subject to limitation pursuant to Internal Revenue Code 382. The Company also had federal and state research and development tax credit carryforwards of approximately $2,854 and $678, respectively. The federal credits will begin expiring in 2025 unless previously utilized. The Connecticut credit carryforwards have no expiration period. Because of the net operating loss and research credit carryforwards, tax years 2007 through 2014 remain open to U.S. federal and state tax examinations.

License and Research Agreement	12 Months Ended
License and Research Agreement	Dec. 31, 2014
Research and Development [Abstract]
License and Research Agreement	14. License and Research Agreement Effective April 2005, the Company entered into a semi-exclusive worldwide royalty-free license agreement (the “Glasgow License Agreement”) for a certain G protein-coupled receptor (“GPCR”) assay technology with the University of Glasgow (“Glasgow”). The Company issued 200,000 shares of its common stock to Glasgow as compensation for this license. Upon an exit event, including an IPO or as otherwise defined in the Glasgow License Agreement, Glasgow had the option to require the Company to guarantee a return of $1,000 on its 200,000 shares of common stock. If the proceeds from the exit event resulted in a return of less than $1,000, the Company was required to make an additional license payment by giving Glasgow cash or through the issuance of additional shares (at the Company’s option), as specified in the Glasgow License Agreement. In accordance with ASC 480, Distinguishing Liabilities from Equity, the Company initially recorded the fair value of this option as both a long-term liability and research and development expense. The Company estimated the fair value of the option using the Black-Scholes option valuation model with consideration given to the probability of an exit event occurring below the guaranteed amount. The fair value of the liability was estimated at each subsequent balance sheet date, with any increases or decreases to the fair value recorded as increases or decreases to research and development expense and the related liability. As of December 31, 2013, the estimated fair value of the liability was reduced to zero based on the Company’s estimated fair value of common stock after the Maruishi transaction (see Note 11, Collaborations). The Company classified the liability within Level 3 as the probability factor is an unobservable input and significant to the valuation model. The Company used a probability factor of 10% in all periods from 2005 to 2013. The probability rate was based on the successful progress of the Company’s product candidates containing CR845 and the Company’s expectation of an exit event value below the guaranteed amount. An increase in the probability rate would have resulted in a higher liability while an increase in the stock price would have reduced the liability. The decrease in the value of the liability of $35 in 2013 was the result of changes in the observable inputs (i.e. stock value, interest rates and volatility) and was recorded in research and development expense. The closing of the Company’s IPO on February 5, 2014 constituted an exit event under the Glasgow License Agreement. Since the public offering price in the IPO was $11.00 per share, the aggregate exit event value was greater than the guaranteed amount. Consequently, as of December 31, 2014, the Company no longer has a liability under the Glasgow License Agreement.

- Definition

The entire disclosure for research, development, and computer software activities, including contracts and arrangements to be performed for others and with federal government. Includes costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility and in-process research and development acquired in a business combination consummated during the period.

+ References + Details

Net Loss per Share

12 Months Ended

Dec. 31, 2014

Earnings Per Share [Abstract]

Net Loss per Share

15. Net Loss per Share

The Company computes net loss per share available to common stockholders in accordance with ASC 260-10, Earnings per Share (see Note 2, Significant Accounting Policies – Income (Loss) per Share).

The denominators used in the net loss per share available to common stockholders computations are as follows:


	Year Ended December 31,
	2014		2013		2012
Basic:
Weighted average shares outstanding		20,965,935		4,133,138		3,299,993

Diluted:
Weighted average shares outstanding – Basic		20,965,935		4,133,138		3,299,993
Convertible preferred stock*		—		—		—
Common stock options*		—		—		—
Common stock warrants*		—		—		—
Convertible promissory notes (as converted)*		—		—		—

Demoninator for diluted net loss per share available to common stockholders		20,965,935		4,133,138		3,299,993

*	No amounts were considered as their effects would be anti-dilutive.

Basic and diluted net loss per share available to common stockholders are computed as follows:


	Year Ended December 31,
	2014			2013			2012
Net loss	$	(17,745	)	$	(3,963	)	$	(6,271	)
Add back: extinguishment of preferred shares		—			891			—

Net loss available to common stockholders – Basic and Diluted	$	(17,745	)	$	(3,072	)	$	(6,271	)

Net loss per share available to common stockholders:
Basic and Diluted	$	(0.85	)	$	(0.74	)	$	(1.90	)
Weighted-average common shares outstanding available to common stockholders
Basic and Diluted		20,965,935			4,133,138			3,299,993

Securities outstanding at the end of the respective periods presented below, that could potentially dilute basic earnings per share in the future, that were not included in the computation of diluted net loss per share because to do so would have been antidilutive are as follows:


	Year Ended December 31,
	2014		2013		2012
Convertible preferred stock		—		12,554,171		11,594,757
Common stock options		1,022,360		490,160		557,160
Common stock warrants		—		19,851		19,851
Convertible promissory notes		—		—		702,928

All shares of the Company’s convertible preferred stock were automatically converted to shares of the Company’s common stock upon the closing of the IPO on February 5, 2014 (see Note 9, Convertible Preferred Stock). All convertible promissory notes were either converted into shares of the Company’s Series D convertible preferred stock or repaid in cash by December 31, 2013 (see Note 7, Convertible Promissory Notes). All common stock warrants were exercised in a cashless exercise on July 31, 2014 (see Note 8, Long-Term Debt).

Related Party Transactions	12 Months Ended
Related Party Transactions	Dec. 31, 2014
Related Party Transactions [Abstract]
Related Party Transactions	16. Related Party Transactions The Company is party to a consulting agreement with a founder and a common stockholder of the Company who provides scientific advisory services. Total expenses under this agreement were $169, $134 and $129 for the years ended December 31, 2014, 2013 and 2012, respectively. Included in accounts payable and accrued expenses as of December 31, 2014 and 2013, respectively, was $35 and $0 for amounts due to this stockholder.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References + Details

Employee Benefit Plan	12 Months Ended
Employee Benefit Plan	Dec. 31, 2014
Postemployment Benefits [Abstract]
Employee Benefit Plan	17. Employee Benefit Plan In February 2006, the Company adopted a defined contribution retirement plan that complies with Section 401(k) of the Internal Revenue Code. All employees over the age of 21 are eligible to participate in the plan after three consecutive months of service. Employees are able to defer a portion of their pay into the plan on the first day of the quarter on or after the day all age and service requirements have been met. The plan allows the Company to match employee contributions; however, there have not been any matching contributions paid through December 31, 2014. Effective January 1, 2015, all eligible employees will receive an employer contribution equal to 3% of their salary up to the annual IRS limit.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2014

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

18. Commitments and Contingencies

Operating Leases

The Company leases its operating facility located in Shelton, Connecticut. The lease agreement, as amended, requires monthly lease payments through October 2017. The lease is renewable thereafter for two successive terms of five years. At inception of the lease, the Company received an incentive allowance from the landlord of $2,127. The Company recorded the incentive allowance as leasehold improvements and deferred lease obligation. The Company is recording monthly rent expense associated with the lease on a straight-line basis over the ten-year minimum term of the lease reduced by the amortization of the deferred lease obligation over the same time period. As a result of this straight-line basis, deferred lease obligation includes $582 and $790 of unamortized incentive allowance plus $292 and $349 of accrued rent at December 31, 2014 and 2013, respectively.

Total rent expense under the operating lease was $643, $616 and $618 for the years ended December 31, 2014, 2013, and 2012, respectively.

Future minimum rental payments under the operating lease at December 31, 2014 are as follows:


2015	$	886
2016		913
2017		740

Total	$	2,539

In conjunction with the signing of the Shelton, Connecticut lease, the Company entered into a standby letter of credit agreement for $2,170, which expires on May 31, 2017 as a security deposit for the premises. In accordance with the terms of the lease, because no drawing was made against the standby letter of credit nor has any default under the operating lease occurred, the amount of the letter of credit was automatically reduced by $294 annually starting March 1, 2008 until the stated amount reached a balance of $700, which occurred in 2012. This standby letter of credit is secured with restricted cash (refer to Note 5, Restricted Cash).

Legal Matters	12 Months Ended
Legal Matters	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Legal Matters	19. Legal Matters From time to time, the Company may become involved in arbitrations or legal proceedings that arise in the ordinary course of its business. The Company cannot predict the timing or outcome of these claims and proceedings. Currently, the Company is not involved in any such arbitration and/or legal proceeding that it expects to have a material effect on its financial condition, results of operations or business.

Quarterly Results of Operations

12 Months Ended

Dec. 31, 2014

Quarterly Financial Information Disclosure [Abstract]

Quarterly Results of Operations

20. Quarterly Results of Operations (Unaudited)

The following tables contain selected financial data for each quarter of the years ended December 31, 2014 and 2013. The Company believes that the following information reflects all normal recurring adjustments necessary for a fair presentation of the information for each quarter of the years ended December 31, 2014 and 2013. The operating results for any period are not necessarily indicative of results for any future periods.


	Year Ended December 31, 2014
	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
Revenues	$	178		$	960		$	1,125		$	914

Net loss available to common stockholders – Basic and Diluted		(3,383	)		(3,645	)		(6,545	)		(4,172	)

Loss per share available to common stockholders – Basic and Diluted	$	(0.22	)	$	(0.16	)	$	(0.29	)	$	(0.18	)


	Year Ended December 31, 2013
	First Quarter			Second Quarter		Third Quarter			Fourth Quarter
Revenues	$	—		$	9,973	$	1,018		$	973

Net (loss) income available to common stockholders – Basic		(1,748	)		1,475		(4,575	)		(2,093	)

Net (loss) income available to common stockholders – Diluted		(1,748	)		5,424		(4,575	)		(2,093	)

(Loss) income per share available to common stockholders – Basic	$	(0.48	)	$	0.34	$	(1.07	)	$	(0.49	)

(Loss) income per share available to common stockholders – Diluted	$	(0.48	)	$	0.33	$	(1.07	)	$	(0.49	)

During the year ended December 31, 2013, the Company used the two-class method to calculate income (loss) per share (refer to Note 2 – Significant Accounting Policies – Income (Loss) per Share). During the second quarter of the year ended December 31, 2013, the Company recorded net income, although for the full year ended December 31, 2013, the Company recorded net loss. For purposes of calculating basic net income per share for the second quarter, the Company excluded from the numerator $3,869 of net income attributable to participating securities. For purposes of calculating diluted earnings per share, such amount was included in the numerator together with interest on convertible promissory notes. Common shares issuable upon exercise of outstanding stock options, assumed conversion of convertible preferred stock and convertible promissory notes were included in the denominator on an as-if converted basis.

However, net loss for the full year ended December 31, 2013 was not allocated to preferred stockholders because they are not obligated to participate in the Company’s net losses. Diluted loss per share excluded common shares issuable upon exercise of outstanding stock options, assumed conversion of convertible preferred stock and convertible promissory notes because they were anti-dilutive. Consequently, the sum of net (loss) income and net (loss) income per share for the quarters in the table above do not equal those measures for the full year ended December 31, 2013.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2014

Accounting Policies [Abstract]

Use of Estimates

Use of Estimates

Fair Value Measurements

Fair Value Measurements

•

Level 1 – Observable inputs – quoted prices in active markets for identical assets and liabilities.

•

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 December 31, 2014 and 2013 and by level within the fair value hierarchy:


	December 31, 2014		December 31, 2013
	Level 1		Level 1
Financial assets
Cash equivalents:
Money market savings account and checking account	$	52,663	$	12,357
Restricted cash:
Bank Certificate of Deposit		700		700

Total	$	53,363	$	13,057

The following table represents a rollforward of the fair value of Level 3 instruments (significant unobservable inputs):


	Year Ended December 31, 2013
Liabilities
Balance at beginning of period	$	76
Amounts acquired or issued		—
Net (gains) losses (realized and unrealized)		(76	)
Net settlements		—

Balance at end of period	$	—

Cash and Cash Equivalents

Cash and Cash Equivalents

Concentration of Credit Risk

Concentration of Credit Risk

Property and Equipment

Property and Equipment


Asset Category	Useful Lives
Computer and office equipment		5 years
Laboratory equipment		8 years
Furniture and fixtures		7 years
Software		3 years
Leasehold improvements		10 years

Long-Lived Assets

Long-Lived Assets

Common Stock and Convertible Preferred Stock Valuation

Common Stock and Convertible Preferred Stock Valuation

Revenue Recognition

Revenue Recognition

Royalty revenue is recognized when earned. To date, no royalties have been earned or were otherwise due to the Company.

Research and Development Expenses

Research and Development Expenses

Income Taxes

Income Taxes

Stock-Based Compensation

Stock-Based Compensation

Income (Loss) Per Share

Income (Loss) Per Share

Segment Reporting

Segment Reporting

Leases

Leases

Litigation Reserves

Litigation Reserves

Reclassifications

Reclassifications

Certain revenue within the Statement of Operations has been reclassified from Collaborative revenue to Clinical compound revenue to conform to the current year presentation.

Recent Accounting Pronouncements

Recent Accounting Pronouncements

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2014

Accounting Policies [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 December 31, 2014 and 2013 and by level within the fair value hierarchy:


	December 31, 2014		December 31, 2013
	Level 1		Level 1
Financial assets
Cash equivalents:
Money market savings account and checking account	$	52,663	$	12,357
Restricted cash:
Bank Certificate of Deposit		700		700

Total	$	53,363	$	13,057

Summary of Rollforward of Fair Value of Level 3 Instruments

The following table represents a rollforward of the fair value of Level 3 instruments (significant unobservable inputs):


	Year Ended December 31, 2013
Liabilities
Balance at beginning of period	$	76
Amounts acquired or issued		—
Net (gains) losses (realized and unrealized)		(76	)
Net settlements		—

Balance at end of period	$	—

Summary of Useful Lives of Property and Equipment


Asset Category	Useful Lives
Computer and office equipment		5 years
Laboratory equipment		8 years
Furniture and fixtures		7 years
Software		3 years
Leasehold improvements		10 years

Property and Equipment, Net (Tables)

12 Months Ended

Dec. 31, 2014

Property, Plant and Equipment [Abstract]

Property and Equipment, Net

Property and equipment, net consists of the following:


	December 31,
	2014		2013
Computer and office equipment	$	309	$	275
Laboratory equipment		233		233
Furniture and fixtures		156		153
Software		126		126
Leasehold improvements		7,453		7,453

	$	8,276	$	8,240
Less accumulated depreciation and amortization		6,192		5,415

Property and equipment, net	$	2,084	$	2,825

Accounts Payable and Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2014

Payables and Accruals [Abstract]

Schedule of Accounts Payable and Accrued Expenses

Accounts payable and accrued expenses consist of the following:


	December 31,
	2014		2013
Accounts payable	$	515	$	676
Accrued research projects		549		405
Accrued professional fees		266		739
Accrued compensation and benefits		504		83
Accrued other		112		55

	$	1,946	$	1,958

Convertible Preferred Stock (Tables)

12 Months Ended

Dec. 31, 2014

Text Block [Abstract]

Schedule of Convertible Preferred Stock

The following tables summarize the outstanding Preferred Stock as of December 31, 2013 and December 31, 2012:

As of December 31, 2013


	Preferred Shares Authorized		Preferred Shares Issued and Outstanding		Liquidation Preference		Carrying Value		Common Stock Issuable Upon Conversion
Junior		173,611		173,611	$	500	$	354		69,444
Junior A		2,105,263		2,105,263		8,000		7,642		842,105
Series A		1,677,118		1,677,118		1,677		1,677		670,830
Series B		2,254,417		2,254,417		4,509		4,509		980,163
Series C		10,930,946		10,930,946		33,886		33,886		5,173,413
Series D		12,260,845		12,045,574		17,397		17,518		4,818,216

		29,402,200		29,186,929	$	65,969	$	65,586		12,554,171

As of December 31, 2012


	Preferred Shares Authorized		Preferred Shares Issued and Outstanding		Liquidation Preference		Carrying Value		Common Stock Issuable Upon Conversion
Junior		173,611		173,611	$	500	$	354		69,444
Junior A		—		—		—		—		—
Series A		2,000,000		2,000,000		2,000		2,000		800,000
Series B		2,370,000		2,370,000		4,740		4,740		1,030,434
Series C		11,706,450		11,706,450		36,290		36,290		5,540,457
Series D		10,386,057		10,386,057		15,000		15,138		4,154,422

		26,636,118		26,636,118	$	58,530	$	58,522		11,594,757

Stockholders' (Deficit) Equity (Tables)

12 Months Ended

Dec. 31, 2014

Equity [Abstract]

Summary of Common Stock Reserved for Conversion of Preferred Stock and Exercise of Warrants and Options


	December 31,
	2014		2013
Conversion of Series A convertible preferred		—		670,830
Conversion of Series B convertible preferred		—		901,757
Conversion of Series C convertible preferred		—		4,372,369
Conversion of Series D convertible preferred		—		4,818,216
Conversion of Junior convertible preferred		—		69,444
Conversion of Junior A convertible preferred		—		842,105
Series B and C anti-dilution shares		—		879,450
Exercise of warrant		—		19,851
Exercise of stock options		1,898,360		1,247,959

		1,898,360		13,821,981

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

Summary of Stock Option Activity


	Number of Options			Weighted- Average Exercise Price		Aggregate Intrinsic Value
Outstanding at December 31, 2013		490,160		$	1.34
Granted		884,000			11.24
Exercised		(191,800	)		0.67
Forfeited		(160,000	)		13.26

Outstanding at December 31, 2014		1,022,360		$	8.16	$	2,763

Weighted average remaining contractual life as of December 31, 2014 (yrs)		7.78

Options exercisable at December 31, 2014		299,735		$	2.11	$	2,366

Weighted average remaining contractual life as of December 31, 2014 (yrs)		3.90

Options vested and expected to vest at December 31, 2014		990,191		$	8.05	$	2,743

Weighted average remaining contractual life as of December 31, 2014 (yrs)		7.73

Summary of Assumptions Used in Black-Scholes Option Pricing Model

The fair values of the stock options granted to those groups during the year ended December 31, 2014 were estimated using the Black-Scholes option valuation model with the following ranges of assumptions (see Note 2, Summary of Significant Accounting Policies – Stock-Based Compensation):


		Year Ended December 31, 2014
Risk-free interest rate		1.64% – 2.72%
Expected volatility		64.9% – 71.3%
Expected dividend yield		0%
Expected life of employee and Board of Directors’ options (in years)		6.25
Expected life of non-employee options (in years)		10

Summary of Compensation Expense Relating to Stock Options

During the years ended December 31, 2014, 2013 and 2012, the Company recognized compensation expense in the accompanying Statements of Operations relating to stock options, as follows:


	Year Ended December 31,
	2014		2013		2012
Research and development	$	349	$	71	$	48
General and administrative		1,022		52		13

Total stock option expense	$	1,371	$	123	$	61

Re-Measurement [Member]

Summary of Assumptions Used in Black-Scholes Option Pricing Model

Year Ended December 31,
	2014	2013	2012
Risk-free interest rate	1.96% – 2.72%	2.5% – 3.2%	1.77%
Expected volatility	69% – 71%	71% – 72%	73%
Expected dividend yield	0%	0%	0%
Expected life of non-employee options (in years)	6 – 10	1.5 – 7	2 – 8

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2014

Income Tax Disclosure [Abstract]

Components of Income Taxes (Benefit)

The Company’s benefit from income taxes is as follows:


	December 31,
	2014			2013			2012
Current:
Federal	$	—		$	—		$	—
State		(201	)		(30	)		(31	)

		(201	)		(30	)		(31	)

Deferred:
Federal		—			—			—
State		—			—			—

		—			—			—

Benefit from income taxes	$	(201	)	$	(30	)	$	(31	)

Schedule of Reconciliation of Income Taxes Computed Using U.S. Federal Statutory Rate to that Reflected in Operations

A reconciliation of income taxes computed using the U.S. federal statutory rate to that reflected in operations is as follows:


	December 31,
	2014			2013			2012
Income taxes using U.S. federal statutory rate		34.00	%		34.00	%		34.00	%
State income taxes, net of federal benefit		5.23	%		6.03	%		5.60	%
Impact of R&D tax credit on effective tax rate		3.03	%		12.04	%		0.00	%
Impact of foreign tax credit on effective tax rate		0.00	%		0.00	%		3.27	%
Stock option shortfalls and cancellations		-0.69	%		0.00	%		-2.54	%
Provision to return adjustments		-0.57	%		-1.42	%		-1.95	%
Change in valuation allowance		-39.88	%		-49.90	%		-37.89	%

		1.12	%		0.75	%		0.49	%

Schedule of Significant Components of Company's Deferred Tax Assets

Significant components of the Company’s deferred tax assets are as follows:


	December 31,
	2014			2013
Net operating loss carryforwards	$	27,094		$	21,433
Federal and state tax credits		3,508			2,947
Accelerated depreciation		1,018			860
Deferred revenue		566			—
Stock-based compensation expense		333			85
Rent expense		114			136
Amortization of R&D intangible assets		56			67
Accrued vacation		27			32

		32,716			25,560
Valuation allowance		(32,716	)		(25,560	)

Net deferred tax asset	$	—		$	—

Net Loss per Share (Tables)

12 Months Ended

Dec. 31, 2014

Earnings Per Share [Abstract]

Computation of Denominators Used in Net Loss Per Share Available to Common Stockholders

The denominators used in the net loss per share available to common stockholders computations are as follows:


	Year Ended December 31,
	2014		2013		2012
Basic:
Weighted average shares outstanding		20,965,935		4,133,138		3,299,993

Diluted:
Weighted average shares outstanding – Basic		20,965,935		4,133,138		3,299,993
Convertible preferred stock*		—		—		—
Common stock options*		—		—		—
Common stock warrants*		—		—		—
Convertible promissory notes (as converted)*		—		—		—

Demoninator for diluted net loss per share available to common stockholders		20,965,935		4,133,138		3,299,993

*	No amounts were considered as their effects would be anti-dilutive.

Computation of Basic and Diluted Net Loss Per Share Available to Common Stockholders

Basic and diluted net loss per share available to common stockholders are computed as follows:


	Year Ended December 31,
	2014			2013			2012
Net loss	$	(17,745	)	$	(3,963	)	$	(6,271	)
Add back: extinguishment of preferred shares		—			891			—

Net loss available to common stockholders – Basic and Diluted	$	(17,745	)	$	(3,072	)	$	(6,271	)

Net loss per share available to common stockholders:
Basic and Diluted	$	(0.85	)	$	(0.74	)	$	(1.90	)
Weighted-average common shares outstanding available to common stockholders
Basic and Diluted		20,965,935			4,133,138			3,299,993

Schedule of Anti-Dilutive Common Stock Equivalents Excluded from Calculations of Diluted Net Loss per Share


	Year Ended December 31,
	2014		2013		2012
Convertible preferred stock		—		12,554,171		11,594,757
Common stock options		1,022,360		490,160		557,160
Common stock warrants		—		19,851		19,851
Convertible promissory notes		—		—		702,928

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2014

Commitments and Contingencies Disclosure [Abstract]

Schedule of Future Minimum Rental Payments Under Operating Leases

Future minimum rental payments under the operating lease at December 31, 2014 are as follows:


2015	$	886
2016		913
2017		740

Total	$	2,539

Quarterly Results of Operations (Tables)

12 Months Ended

Dec. 31, 2014

Quarterly Financial Information Disclosure [Abstract]

Schedule of Selected Financial Data for Each Quarter


	Year Ended December 31, 2014
	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
Revenues	$	178		$	960		$	1,125		$	914

Net loss available to common stockholders – Basic and Diluted		(3,383	)		(3,645	)		(6,545	)		(4,172	)

Loss per share available to common stockholders – Basic and Diluted	$	(0.22	)	$	(0.16	)	$	(0.29	)	$	(0.18	)


	Year Ended December 31, 2013
	First Quarter			Second Quarter		Third Quarter			Fourth Quarter
Revenues	$	—		$	9,973	$	1,018		$	973

Net (loss) income available to common stockholders – Basic		(1,748	)		1,475		(4,575	)		(2,093	)

Net (loss) income available to common stockholders – Diluted		(1,748	)		5,424		(4,575	)		(2,093	)

(Loss) income per share available to common stockholders – Basic	$	(0.48	)	$	0.34	$	(1.07	)	$	(0.49	)

(Loss) income per share available to common stockholders – Diluted	$	(0.48	)	$	0.33	$	(1.07	)	$	(0.49	)

Business - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended				12 Months Ended
	Jan. 30, 2014	Apr. 30, 2013	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Nature Of Business [Line Items]
Date of formation							Jul. 02, 2004
Common stock, shares issued	5,750,000		22,802,039				22,802,039	4,288,243
Common stock, shares issued upon exercise by underwriters	750,000
Aggregate gross offering proceeds	$ 63,250
Net proceeds as a result of IPO	56,297						$ 57,762
Underwriting discounts and commissions	$ 6,953
Net proceeds from equity financing and issuance of debt prior to the IPO								$ 73,309
Unrestricted cash and cash equivalents			$ 52,663				52,663	12,357	$ 1,117	$ 4,097
Accumulated deficit			80,201				80,201	62,456
Net cash (used in) provided by operating activities							17,642	(2,829)	6,031
Net loss available to common stockholders			$ 4,172	$ 6,545	$ 3,645	$ 3,383	$ 17,745	$ 3,072	$ 6,271
Initial Public Offering [Member]
Nature Of Business [Line Items]
Public offering price	$ 11.00		$ 11.00				$ 11.00
Maruishi Stock Purchase Agreement [Member]
Nature Of Business [Line Items]
Net proceeds from equity financing and issuance of debt prior to the IPO		$ 7,642
Maruishi License Agreement [Member]
Nature Of Business [Line Items]
Upfront license fee		$ 15,000

Summary of Significant Accounting Policies - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Detail) - Recurring [Member] - Level 1 [Member] - USD ($) $ in Thousands	Dec. 31, 2014	Dec. 31, 2013
Financial assets
Total	$ 53,363	$ 13,057
Money Market Savings Account and Checking Account [Member]
Financial assets
Cash equivalents	52,663	12,357
Bank Certificate of Deposit [Member]
Financial assets
Restricted cash	$ 700	$ 700

Summary of Significant Accounting Policies - Summary of Rollforward of Fair Value of Level 3 Instruments (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2013 USD ($)
Liabilities
Balance at beginning of period	$ 76
Amounts acquired or issued	0
Net (gains) losses (realized and unrealized)	(76)
Net settlements	$ 0

Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2014 USD ($) Segments	Dec. 31, 2013 USD ($)	Apr. 30, 2013 USD ($)	Jan. 01, 2013 USD ($)	Dec. 31, 2012 USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of liability					$ 76,000
Original maturity period of highly liquid investments	Three months or less
Royalty revenue	$ 0
Prepaid R&D expense	$ 177,000	$ 262,000
Expected dividend yield	0.00%
Reverse stock split, description	1-for-2.5 reverse stock split
Reverse stock split, ratio	2.5
Number of operating segments \| Segments	1
Glasgow License Agreement [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of liability		$ 0		$ 35,000
Beneficial Conversion Feature on Convertible Promissory Notes [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of liability			$ 0	$ 41,000
Maximum [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Maximum contractual life	10 years

Summary of Significant Accounting Policies - Summary of Useful Lives of Property and Equipment (Detail)	12 Months Ended
	Dec. 31, 2014
Computer and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives, years	5 years
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives, years	8 years
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives, years	7 years
Software [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives, years	3 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives, years	10 years

Prepaid Expenses - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2014	Dec. 31, 2013
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid expenses	$ 287	$ 2,140
Prepaid insurance	92	34
Prepaid R&D clinical costs	177	262
Other costs	$ 18	11
IPO costs		$ 1,833

Property and Equipment, Net - Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 8,276	$ 8,240
Less accumulated depreciation and amortization	6,192	5,415
Property and equipment, net	2,084	2,825
Computer and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	309	275
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	233	233
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	156	153
Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	126	126
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 7,453	$ 7,453

Property and Equipment, Net - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense		$ 783	$ 789	$ 1,021
Proceeds from sale of property and equipment				511
Loss on sale of property and equipment				$ 286
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Proceeds from sale of property and equipment	$ 511
Loss on sale of property and equipment	$ 286

Restricted Cash - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash in long-term assets	$ 700	$ 700
Standby Letter of Credit [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Letter of credit, remaining amount	$ 700		$ 700

Accounts Payable and Accrued Expenses - Schedule of Accounts Payable and Accrued Expenses (Detail) - USD ($) $ in Thousands	Dec. 31, 2014	Dec. 31, 2013
Payables and Accruals [Abstract]
Accounts payable	$ 515	$ 676
Accrued research projects	549	405
Accrued professional fees	266	739
Accrued compensation and benefits	504	83
Accrued other	112	55
Total	$ 1,946	$ 1,958

Convertible Promissory Notes - Additional Information (Detail) $ / shares in Units, $ in Thousands				1 Months Ended			12 Months Ended
	Aug. 28, 2013 USD ($) shares	Feb. 28, 2013 USD ($) shares	Dec. 31, 2012 USD ($) $ / shares	Oct. 31, 2013 USD ($)	Apr. 30, 2013 USD ($)	Feb. 28, 2013 USD ($) shares	Dec. 31, 2014 Closings shares	Dec. 31, 2013 USD ($) shares	Dec. 31, 2012 USD ($) $ / shares	Jan. 01, 2013 USD ($)	Dec. 28, 2012 USD ($)
Debt Instrument [Line Items]
Fair value of liability			$ 76						$ 76
Percentage of discount on conversion price	10.00%
Probability of closing a $10,000 equity offering before August 28, 2013					0.00%
Convertible promissory notes converted to Series D convertible preferred stock, Value								$ 3,888
Repayment of convertible promissory notes				$ 311				311
Deferred financing costs			$ 4					117	4
Maruishi License Agreement [Member]
Debt Instrument [Line Items]
Amount received in connection with Maruishi transaction					$ 23,000
Series D Convertible Preferred Stock [Member]
Debt Instrument [Line Items]
Convertible promissory notes converted to Series D convertible preferred stock, Shares \| shares	2,692,291
Convertible promissory notes converted to Series D convertible preferred stock, Value	$ 3,888
Optional Conversion Feature [Member]
Debt Instrument [Line Items]
Debt conversion feature, description							The optional conversion feature allowed the Note holder, any time prior to the Maturity Date, to elect to convert the balance of the note plus accrued interest into Series D convertible preferred stock at a conversion price of $1.444244 per share.
Amortization of debt discount to interest expense								3,407	$ 25
Optional Conversion Feature [Member] \| Series D Convertible Preferred Stock [Member]
Debt Instrument [Line Items]
Conversion price per share \| $ / shares			$ 1.444244						$ 1.444244
Estimated fair value of preferred stock \| $ / shares			$ 2.61
Mandatory Conversion Feature [Member]
Debt Instrument [Line Items]
Debt conversion feature, description							The mandatory conversion of the Notes would have occurred in the event the Company issued or sold equity securities on or before August 28, 2013 of not less than $10,000. In this event, the Notes plus all accrued interest would have automatically converted into the issued class of equity securities at a price per share equal to 90% of the cash price paid by the investors in the new equity securities.
Latest date equity securities issued for mandatory conversion							Aug. 28, 2013
Conversion condition, value of shares issued	$ 10,000
Amount in which promissory notes are converted as a percentage of the price paid by new investors	90.00%
Beneficial Conversion Feature on Convertible Promissory Notes [Member]
Debt Instrument [Line Items]
Debt, face amount		$ 1,462				$ 1,462		4,000			$ 2,538
Number of closings \| Closings							2
Debt, maturity date							Aug. 28, 2013
Debt, initial closing date							Dec. 28, 2012
Debt, final closing date							Feb. 28, 2013
Debt, interest rate		8.00%				8.00%
Beneficial conversion feature								$ 1,382	$ 2,050
Fair value of liability					$ 0					$ 41
Beneficial Conversion Feature on Convertible Promissory Notes [Member] \| Optional Conversion Feature [Member]
Debt Instrument [Line Items]
Beneficial conversion feature		$ 1,382							2,050
Beneficial Conversion Feature on Convertible Promissory Notes [Member] \| Mandatory Conversion Feature [Member]
Debt Instrument [Line Items]
Fair value of liability			$ 41						$ 41
Convertible Preferred Stock [Member]
Debt Instrument [Line Items]
Preferred stock converted to common shares \| shares		2,246,743				2,246,743	(29,186,929)	(2,246,743)
Carrying value of convertible preferred stock								$ 4,466
Common Stock [Member]
Debt Instrument [Line Items]
Preferred stock converted to common shares \| shares		959,545				959,545	12,554,171	959,545
Fair value of common stock issued								$ 3,575
Accumulated Deficit [Member]
Debt Instrument [Line Items]
Gain on conversion of preferred stock to common stock								$ 891

Long-Term Debt - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended		12 Months Ended
	Jul. 31, 2014	Apr. 30, 2013	Sep. 30, 2007	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 04, 2012
Debt Instrument [Line Items]
Repayment of long-term debt					$ 307	$ 446
Exercise price, per share				$ 10.08
Number of shares to be purchased under warrant				19,851
Warrant exercise date				Jul. 31, 2014
Common stock issued in result of warrants exercise	6,383
Term Loan [Member]
Debt Instrument [Line Items]
Debt, face amount			$ 4,000
Debt, interest rate			7.00%				8.50%
Debt, frequency of periodic payments				Monthly installments over five years
Debt, payment period			5 years
Debt, default description				If the Company failed to maintain its Connecticut presence, all amounts due under the Loan would be immediately due and payable with the cumulative interest rate increasing to 25%.
Debt, cumulative interest rate			25.00%
Repayment of long-term debt		$ 307

Convertible Preferred Stock - Additional Information (Detail)			1 Months Ended		12 Months Ended
	Feb. 05, 2014 shares	Feb. 28, 2013 shares	Sep. 30, 2013 shares	Feb. 28, 2013 shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) $ / shares shares	Apr. 30, 2013 USD ($) shares	Dec. 31, 2012 USD ($) shares	May 31, 2012 USD ($) $ / shares shares	Dec. 31, 2011 shares
Temporary Equity [Line Items]
Convertible Preferred stock, shares issued	29,186,929				0	29,186,929		26,636,118
Convertible Preferred stock, par value \| $ / shares					$ 0.001	$ 0.001
Convertible Preferred stock, shares outstanding	29,186,929				0	29,186,929		26,636,118
Conversion of stock, shares issued	12,554,171
Closing date of IPO					Feb. 05, 2014
Convertible Preferred stock, shares authorized					0	29,402,200		26,636,118
Liquidation preference \| $					$ 0	$ 65,969,000		$ 58,530,000
Preferred stock to common stock conversion ratio					2.5
Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Preferred stock converted to common shares		2,246,743		2,246,743	(29,186,929)	(2,246,743)
Convertible promissory notes converted to Series D convertible preferred stock, Shares						2,692,291
Convertible Preferred stock, shares outstanding						29,186,929		26,636,118		26,462,507
Dividends declared or paid \| $					$ 0
Common Stock [Member]
Temporary Equity [Line Items]
Preferred stock converted to common shares		959,545		959,545	12,554,171	959,545
Junior Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible Preferred stock, shares issued						173,611		173,611
Convertible Preferred stock, shares outstanding						173,611		173,611
Convertible Preferred stock, shares authorized						173,611		173,611
Liquidation preference \| $						$ 500,000		$ 500,000
Preferred stock to common stock conversion ratio						0.4
Junior Convertible Preferred Stock [Member] \| Chong Kun Dang Pharmaceutical Corporation [Member] \| Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible Preferred stock, shares issued									173,611
Convertible Preferred stock, par value \| $ / shares									$ 0.001
Convertible Preferred stock, estimated fair value \| $									$ 354,000
Junior A Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible Preferred stock, shares issued						2,105,263
Convertible Preferred stock, shares outstanding						2,105,263
Convertible Preferred stock, shares authorized						2,105,263
Liquidation preference \| $						$ 8,000,000
Preferred stock to common stock conversion ratio						0.4
Junior A Convertible Preferred Stock [Member] \| Maruishi Pharmaceutical Co., Ltd. [Member] \| Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible Preferred stock, shares issued							2,105,263
Convertible Preferred stock, estimated fair value \| $							$ 7,663,000
Series D Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible Preferred stock, shares issued						12,045,574		10,386,057
Convertible promissory notes converted to Series D convertible preferred stock, Shares			2,692,291
Convertible Preferred stock, shares outstanding						12,045,574		10,386,057
Convertible Preferred stock, shares authorized						12,260,845		10,386,057
Liquidation preference \| $						$ 17,397,000		$ 15,000,000
Preferred stock to common stock conversion ratio						0.4
Minimum percentage of stock required for conversion of outstanding Preferred Stock to common stock					67.00%
Series D Convertible Preferred Stock [Member] \| Maximum [Member]
Temporary Equity [Line Items]
Liquidation preference \| $						$ 70,000,000
Liquidation preference per share \| $ / shares						$ 4.332732
Series C Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible Preferred stock, shares issued						10,930,946		11,706,450
Convertible Preferred stock, shares outstanding						10,930,946		11,706,450
Convertible Preferred stock, shares authorized						10,930,946		11,706,450
Liquidation preference \| $						$ 33,886,000		$ 36,290,000
Preferred stock to common stock conversion ratio						0.473282
Series B Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible Preferred stock, shares issued						2,254,417		2,370,000
Convertible Preferred stock, shares outstanding						2,254,417		2,370,000
Convertible Preferred stock, shares authorized						2,254,417		2,370,000
Liquidation preference \| $						$ 4,509,000		$ 4,740,000
Preferred stock to common stock conversion ratio						0.434782
Series A Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible Preferred stock, shares issued						1,677,118		2,000,000
Convertible Preferred stock, shares outstanding						1,677,118		2,000,000
Convertible Preferred stock, shares authorized						1,677,118		2,000,000
Liquidation preference \| $						$ 1,677,000		$ 2,000,000
Preferred stock to common stock conversion ratio						0.4

Convertible Preferred Stock - Schedule of Convertible Preferred Stock (Detail) - USD ($) $ in Thousands	Dec. 31, 2014	Feb. 05, 2014	Dec. 31, 2013	Dec. 31, 2012
Temporary Equity [Line Items]
Preferred Shares Authorized	0		29,402,200	26,636,118
Preferred Shares Issued	0	29,186,929	29,186,929	26,636,118
Preferred Shares Outstanding	0	29,186,929	29,186,929	26,636,118
Liquidation preference	$ 0		$ 65,969	$ 58,530
Carrying Value			$ 65,586	$ 58,522
Common Stock Issuable Upon Conversion			12,554,171	11,594,757
Junior Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Preferred Shares Authorized			173,611	173,611
Preferred Shares Issued			173,611	173,611
Preferred Shares Outstanding			173,611	173,611
Liquidation preference			$ 500	$ 500
Carrying Value			$ 354	$ 354
Common Stock Issuable Upon Conversion			69,444	69,444
Junior A Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Preferred Shares Authorized			2,105,263
Preferred Shares Issued			2,105,263
Preferred Shares Outstanding			2,105,263
Liquidation preference			$ 8,000
Carrying Value			$ 7,642
Common Stock Issuable Upon Conversion			842,105
Series A Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Preferred Shares Authorized			1,677,118	2,000,000
Preferred Shares Issued			1,677,118	2,000,000
Preferred Shares Outstanding			1,677,118	2,000,000
Liquidation preference			$ 1,677	$ 2,000
Carrying Value			$ 1,677	$ 2,000
Common Stock Issuable Upon Conversion			670,830	800,000
Series B Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Preferred Shares Authorized			2,254,417	2,370,000
Preferred Shares Issued			2,254,417	2,370,000
Preferred Shares Outstanding			2,254,417	2,370,000
Liquidation preference			$ 4,509	$ 4,740
Carrying Value			$ 4,509	$ 4,740
Common Stock Issuable Upon Conversion			980,163	1,030,434
Series C Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Preferred Shares Authorized			10,930,946	11,706,450
Preferred Shares Issued			10,930,946	11,706,450
Preferred Shares Outstanding			10,930,946	11,706,450
Liquidation preference			$ 33,886	$ 36,290
Carrying Value			$ 33,886	$ 36,290
Common Stock Issuable Upon Conversion			5,173,413	5,540,457
Series D Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Preferred Shares Authorized			12,260,845	10,386,057
Preferred Shares Issued			12,045,574	10,386,057
Preferred Shares Outstanding			12,045,574	10,386,057
Liquidation preference			$ 17,397	$ 15,000
Carrying Value			$ 17,518	$ 15,138
Common Stock Issuable Upon Conversion			4,818,216	4,154,422

Stockholders' (Deficit) Equity - Additional Information (Detail) $ / shares in Units, $ in Thousands			12 Months Ended
	Dec. 01, 2014 USD ($) $ / shares shares	Jan. 30, 2014 $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2012 USD ($)	Jan. 16, 2014 $ / shares shares	Dec. 31, 2013 $ / shares shares
Class of Stock [Line Items]
Common stock, shares authorized			100,000,000		100,000,000	50,000,000
Common stock, par value \| $ / shares			$ 0.001		$ 0.001	$ 0.001
Preferred stock, shares authorized			5,000,000		5,000,000	0
Preferred stock, par value \| $ / shares			$ 0.001		$ 0.001	$ 0.001
Common stock, shares outstanding			22,802,039			4,288,243
Preferred stock, shares issued			0			0
Preferred stock, shares outstanding			0			0
Reverse stock split, description			1-for-2.5 reverse stock split
Reverse stock split, ratio			2.5
Reverse stock split, effective date			Jan. 16, 2014
Common stock, shares issued		5,750,000
Gross proceeds of common stock \| $			$ 100	$ 86
Preferred stock, conversion date			Feb. 05, 2014
Outstanding warrants exercised, date			Jul. 31, 2014
Initial Public Offering [Member]
Class of Stock [Line Items]
Public offering price \| $ / shares		$ 11.00	$ 11.00
Chief Medical Officer [Member]
Class of Stock [Line Items]
Common stock, shares issued	11,442
Public offering price \| $ / shares	$ 8.74
Gross proceeds of common stock \| $	$ 100

Stockholders' (Deficit) Equity - Summary of Common Stock Reserved For Conversion of Preferred Stock and Exercise of Warrants and Options (Detail) - shares	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Class of Stock [Line Items]
Exercise of warrant		19,851
Exercise of stock options	1,898,360	1,247,959
Common stock reserved for conversion of Preferred Stock and exercise of warrants and options	1,898,360	13,821,981
Series A Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Common stock reserved for conversion of Preferred Stock		670,830
Series B Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Common stock reserved for conversion of Preferred Stock		901,757
Series C Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Common stock reserved for conversion of Preferred Stock		4,372,369
Series D Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Common stock reserved for conversion of Preferred Stock		4,818,216
Junior Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Common stock reserved for conversion of Preferred Stock		69,444
Junior A Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Common stock reserved for conversion of Preferred Stock		842,105
Series B and C Anti-Dilution Shares [Member]
Class of Stock [Line Items]
Common stock reserved for conversion of Preferred Stock		879,450

Collaborations - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended			12 Months Ended
	Jun. 30, 2014	Apr. 30, 2013	Apr. 30, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 05, 2014	May 31, 2012
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
License and milestone revenue				$ 302	$ 9,637	$ 1,190
Deferred R&D service revenue				1,452	3,475
Collaborative revenue				$ 2,201	$ 2,225
Issuance of convertible preferred stock				0	29,186,929	26,636,118	29,186,929
Revenue recognized from sale of clinical compound				$ 674	$ 102
Research and development expense				15,068	$ 8,685	$ 4,597
Junior Convertible Preferred Stock [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Issuance of convertible preferred stock					173,611	173,611
Junior A Convertible Preferred Stock [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Issuance of convertible preferred stock					2,105,263
Maruishi License Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Research and development expense				3,558	$ 2,452
Clinical trial costs related to the R&D services deliverable				3,000	2,420
Cost of clinical compound sold to Maruishi				558	32
Chong Kun Dang Pharmaceutical Corporation [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront non-refundable, non-creditable license fee			$ 1,000
Milestone payments receivable			3,750
License and milestone revenue			$ 646			$ 1,190
Milestone payments						750
Revenue recognized from substantive milestones				250
South Korean Withholding tax						$ 206
Chong Kun Dang Pharmaceutical Corporation [Member] \| Junior Convertible Preferred Stock [Member] \| Convertible Preferred Stock [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Issuance of convertible preferred stock, Shares			173,611
Issuance of convertible preferred stock, Value			$ 354
Issuance of convertible preferred stock								173,611
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]
Upfront non-refundable, non-creditable license fee		$ 15,000
License and milestone revenue				302	9,637
Revenue recognized from substantive milestones				2,500
Value of arrangement		15,337
Deferred R&D service revenue				1,452	3,475
Revenue recognized from nonsubstantive milestones				8,000
Non-refundable contingent payment	$ 480
Collaborative revenue				2,201	2,225
Stock purchase agreement, purchase price of preferred stock		8,000
Stock purchase agreement, purchase price fair value of preferred stock		$ 7,663
Stock purchase agreement, purchase price fair value of preferred stock per share		$ 3.64
Stock purchase agreement, purchase price premium of preferred stock		$ 337
Revenue recognized from sale of clinical compound				674	$ 102
Maruishi Pharmaceutical Co., Ltd. [Member] \| Junior A Convertible Preferred Stock [Member] \| Convertible Preferred Stock [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Issuance of convertible preferred stock		2,105,263
Stock purchase agreement, purchase price of preferred stock per share		$ 3.80
Maruishi Pharmaceutical Co., Ltd. [Member] \| Clinical Development [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Milestone payment due				$ 2,000
Maruishi Pharmaceutical Co., Ltd. [Member] \| License [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
License and milestone revenue	302	$ 9,637
Estimated selling price		10,200
Maruishi Pharmaceutical Co., Ltd. [Member] \| R & D Services [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Estimated selling price		6,200
Deferred R&D service revenue	90	$ 5,700
Collaborative revenue	$ 88

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jan. 01, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2014	Jan. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of options vested		$ 393	$ 75	$ 65
Intrinsic value of options exercised		$ 2,055	$ 0	$ 10
Options granted			0	0
Fair value of options granted		$ 7.09
Compensation expense not yet recognized		$ 3,768
Weighted average period of compensation expense not yet recognized		3 years 2 months 27 days
Re-Measurement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of options granted		$ 10.77	$ 6.54	$ 1.77
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
Share-based compensation arrangement by share-based payment award, number of shares authorized		1,600,000
Annual increase in number of shares reserved for issuance as a percentage of shares of capital stock outstanding through January 1, 2024		3.00%
Options granted		884,000
2014 Equity Incentive Plan [Member] \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in aggregate number of shares that may be issued	2,284,061
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
2004 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for future issuance			757,799		0	0
2004 Stock 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%
2004 Stock 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
2004 Stock Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of awards granted		10 years

Stock-Based Compensation - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Granted		0	0
2014 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Outstanding at December 31, 2013	490,160
Number of Options, Granted	884,000
Number of Options, Exercised	(191,800)
Number of Options, Forfeited	(160,000)
Number of Options, Outstanding at December 31, 2014	1,022,360	490,160
Number of Options, Outstanding, Weighted average remaining contractual life as of December 31, 2014	7 years 9 months 11 days
Number of Options, Options exercisable at December 31, 2014	299,735
Number of Options, Exercisable, Weighted average remaining contractual life as of December 31, 2014	3 years 10 months 24 days
Number of Options, Options vested and expected to vest at December 31, 2014	990,191
Number of Options, Vested and expected to vest, Weighted average remaining contractual life as of December 31, 2014	7 years 8 months 23 days
Weighted-Average Exercise Price, Outstanding at December 31, 2013	$ 1.34
Weighted-Average Exercise Price, Granted	11.24
Weighted-Average Exercise Price, Exercised	0.67
Weighted-Average Exercise Price, Forfeited	13.26
Weighted-Average Exercise Price, Outstanding at December 31, 2014	8.16	$ 1.34
Weighted-Average Exercise Price, Options exercisable at December 31, 2014	2.11
Weighted-Average Exercise Price, Options vested and expected to vest at December 31, 2014	$ 8.05
Aggregate Intrinsic Value, Outstanding at December 31, 2014	$ 2,763
Aggregate Intrinsic Value, Options exercisable at December 31, 2014	2,366
Aggregate Intrinsic Value, Options vested and expected to vest at December 31, 2014	$ 2,743

Stock-Based Compensation - Summary of Assumptions Used in Black-Scholes Option Pricing Model (Detail)	12 Months Ended
	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	1.64%
Risk-free interest rate, maximum	2.72%
Expected volatility, minimum	64.90%
Expected volatility, maximum	71.30%
Expected dividend yield	0.00%
Employee and Board of Directors Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life of options (in years)	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

Stock-Based Compensation - Summary of Re-measurement of Assumptions Used in Black-Scholes Option Pricing Model (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	1.64%
Risk-free interest rate, maximum	2.72%
Expected volatility, minimum	64.90%
Expected volatility, maximum	71.30%
Expected dividend yield	0.00%
Nonemployee Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life of options (in years)	10 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life of options (in years)	10 years
Re-Measurement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate			1.77%
Risk-free interest rate, minimum	1.96%	2.50%
Risk-free interest rate, maximum	2.72%	3.20%
Expected volatility			73.00%
Expected volatility, minimum	69.00%	71.00%
Expected volatility, maximum	71.00%	72.00%
Expected dividend yield	0.00%	0.00%	0.00%
Re-Measurement [Member] \| Minimum [Member] \| Nonemployee Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life of options (in years)	6 years	1 year 6 months	2 years
Re-Measurement [Member] \| Maximum [Member] \| Nonemployee Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life of options (in years)	10 years	7 years	8 years

Stock-Based Compensation - Summary of Compensation Expense Relating to Stock Options (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock option expense	$ 1,371	$ 123	$ 61
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock option expense	349	71	48
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock option expense	$ 1,022	$ 52	$ 13

Income Taxes - Components of Income Taxes (Benefit) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current:
Federal	$ 0	$ 0	$ 0
State	(201)	(30)	(31)
Total Current	(201)	(30)	(31)
Deferred:
Federal	0	0	0
State	0	0	0
Total Deferred	0	0	0
Benefit from income taxes	$ (201)	$ (30)	$ (31)

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Income Taxes [Line Items]
Percentage of annual research and development credit for cash	65.00%
Valuation allowance on the deferred tax asset	100.00%	100.00%
Change in valuation allowance	$ 7,156,000	$ 667,000
Tax benefit on exercise of non-qualified stock options and disqualified disposition of incentive stock options	401,000
Unrecognized tax benefits	0	0
Unrecognized tax benefits, related interest and penalties	$ 0	$ 0
Tax examinations, description	Tax years 2007 through 2014 remain open to U.S. federal and state tax examinations.
Earliest Tax Year [Member]
Income Taxes [Line Items]
Open tax years	2007
Latest Tax Year [Member]
Income Taxes [Line Items]
Open tax years	2014
Federal [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 71,369,000
Federal [Member] \| Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax loss carryforwards expiration year	2026
Federal [Member] \| Research and Development Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Tax credit carryforwards	$ 2,854,000
Federal [Member] \| Research and Development Tax Credit Carryforward [Member] \| Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax credit expiration year	2025
State and Local [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 65,260,000
State and Local [Member] \| Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax loss carryforwards expiration year	2027
State and Local [Member] \| Research and Development Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Tax credit carryforwards	$ 678,000

Income Taxes - Schedule of Reconciliation of Income Taxes Computed Using U.S. Federal Statutory Rate to that Reflected in Operations (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Income taxes using U.S. federal statutory rate	34.00%	34.00%	34.00%
State income taxes, net of federal benefit	5.23%	6.03%	5.60%
Impact of R&D tax credit on effective tax rate	3.03%	12.04%	0.00%
Impact of foreign tax credit on effective tax rate	0.00%	0.00%	3.27%
Stock option shortfalls and cancellations	(0.69%)	0.00%	(2.54%)
Provision to return adjustments	(0.57%)	(1.42%)	(1.95%)
Change in valuation allowance	(39.88%)	(49.90%)	(37.89%)
Total	1.12%	0.75%	0.49%

Income Taxes - Schedule of Significant Components of Company's Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Net operating loss carryforwards	$ 27,094	$ 21,433
Federal and state tax credits	3,508	2,947
Accelerated depreciation	1,018	860
Deferred revenue	566
Stock-based compensation expense	333	85
Rent expense	114	136
Amortization of R&D intangible assets	56	67
Accrued vacation	27	32
Gross deferred tax asset	32,716	25,560
Valuation allowance	(32,716)	(25,560)
Net deferred tax asset	$ 0	$ 0

License and Research Agreement - Additional Information (Detail) - USD ($)		12 Months Ended
	Apr. 01, 2005	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008	Dec. 31, 2007	Dec. 31, 2006	Dec. 31, 2005	Feb. 05, 2014	Jan. 01, 2013
Research and Development Assets Acquired Other than Through Business Combination [Line Items]
Fair value of liability				$ 76,000
IPO closing date		Feb. 05, 2014
Glasgow License Agreement [Member]
Research and Development Assets Acquired Other than Through Business Combination [Line Items]
Issuance of common stock as compensation	200,000
Guarantee return on common stock issued as compensation	$ 1,000,000
Fair value of liability			$ 0										$ 35,000
Probability factor percentage			10.00%	10.00%	10.00%	10.00%	10.00%	10.00%	10.00%	10.00%	10.00%
Decrease in fair value of liability			$ (35,000)
Public offering price in the IPO												$ 11.00
IPO closing date		Feb. 05, 2014

Net Loss per Share - Computation of Denominators Used in Net Loss per Share Available to Common Stockholders (Detail) - shares	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Basic:
Weighted average shares outstanding	20,965,935	4,133,138	3,299,993
Diluted:
Weighted average shares outstanding - Basic	20,965,935	4,133,138	3,299,993
Convertible preferred stock	0	0	0
Common stock options	0	0	0
Common stock warrants	0	0	0
Convertible promissory notes (as converted)	0	0	0
Denominator for diluted net loss per share available to common stockholders	20,965,935	4,133,138	3,299,993

Net Loss per Share - Computation of Basic and Diluted Net Loss Per Share Available to Common Stockholders (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Earnings Per Share [Abstract]
Net loss					$ (17,745)	$ (3,963)	$ (6,271)
Add back: extinguishment of preferred shares						891
Net loss available to common stockholders - Basic and Diluted	$ (4,172)	$ (6,545)	$ (3,645)	$ (3,383)	$ (17,745)	$ (3,072)	$ (6,271)
Net loss per share available to common stockholders:
Basic and Diluted	$ (0.18)	$ (0.29)	$ (0.16)	$ (0.22)	$ (0.85)	$ (0.74)	$ (1.90)
Weighted-average common shares outstanding available to common stockholders
Basic and Diluted					20,965,935	4,133,138	3,299,993

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Net Loss per Share - Schedule of Anti-Dilutive Common Stock Equivalents Excluded from Calculations of Diluted Net Loss Per Share (Detail) - shares	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Common Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive common stock equivalents	1,022,360	490,160	557,160
Common Stock Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive common stock equivalents		19,851	19,851
Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive common stock equivalents		12,554,171	11,594,757
Beneficial Conversion Feature on Convertible Promissory Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive common stock equivalents			702,928

Net Loss per Share - Additional Information (Detail)	12 Months Ended
Net Loss per Share - Additional Information (Detail)	Dec. 31, 2014
Earnings Per Share [Abstract]
Warrant exercise date	Jul. 31, 2014

Related Party Transactions - Additional Information (Detail) - Consulting Agreement [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Related Party Transaction [Line Items]
Related party transaction, total expenses	$ 169	$ 134	$ 129
Related party transaction, due to stockholder	$ 35	$ 0

Employee Benefit Plan - Additional Information (Detail)		12 Months Ended
Employee Benefit Plan - Additional Information (Detail)	Jan. 01, 2015	Dec. 31, 2014
Defined Contribution Plan Disclosure [Line Items]
Defined contribution retirement plan, description		All employees over the age of 21 are eligible to participate in the plan after three consecutive months of service.
Subsequent Event [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined contribution retirement plan, employer contribution percentage	3.00%
Minimum [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined contribution retirement plan, employee eligible age to participate		21 years
Defined contribution retirement plan, employee eligible service period		3 months

Commitments and Contingencies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Commitments [Line Items]
Operating lease, expiration date	2017-10
Operating lease, renewable term description	The lease is renewable thereafter for two successive terms of five years.
Incentive allowance received	$ 2,127,000
Unamortized incentive allowance	582,000	$ 790,000
Accrued rent	292,000	349,000
Operating lease, rent expense	$ 643,000	$ 616,000	$ 618,000
Minimum [Member]
Other Commitments [Line Items]
Term of lease	10 years
Standby Letter of Credit [Member]
Other Commitments [Line Items]
Letter of credit, amount	$ 2,170,000
Letter of credit, expiration date	May 31, 2017
Amounts of drawings against letter of credit	$ 0
Letter of credit, annual reduction from 2008 to 2012			294,000
Letter of credit, remaining amount	$ 700,000		$ 700,000

Commitments and Contingencies - Schedule of Future Minimum Rental Payments Under Operating Leases (Detail) $ in Thousands	Dec. 31, 2014 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2015	$ 886
2016	913
2017	740
Total	$ 2,539

Quarterly Results of Operations - Schedule of Selected Financial Data for Each Quarter (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 914	$ 1,125	$ 960	$ 178	$ 973	$ 1,018	$ 9,973		$ 3,177	$ 11,964	$ 1,190
Net (loss) income available to common stockholders - Basic					(2,093)	(4,575)	1,475	$ (1,748)
Net loss available to common stockholders - Basic and Diluted	$ (4,172)	$ (6,545)	$ (3,645)	$ (3,383)					$ (17,745)	$ (3,072)	$ (6,271)
Net (loss) income available to common stockholders - Diluted					$ (2,093)	$ (4,575)	$ 5,424	$ (1,748)
Loss per share available to common stockholders - Basic and Diluted	$ (0.18)	$ (0.29)	$ (0.16)	$ (0.22)					$ (0.85)	$ (0.74)	$ (1.90)
(Loss) income per share available to common stockholders - Basic					$ (0.49)	$ (1.07)	$ 0.34	$ (0.48)
(Loss) income per share available to common stockholders - Diluted					$ (0.49)	$ (1.07)	$ 0.33	$ (0.48)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References + Details

Quarterly Results of Operations - Additional Information (Detail) $ in Thousands	3 Months Ended
	Jun. 30, 2013 USD ($)
Quarterly Financial Information Disclosure [Abstract]
Net income attributable to participating securities	$ 3,869