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Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2013	Jan. 31, 2014	Jun. 30, 2013
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	FY
Trading Symbol	ACAD
Entity Registrant Name	ACADIA PHARMACEUTICALS INC
Entity Central Index Key	0001070494
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		91,348,503
Entity Public Float			$ 1,000,000,000

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2013	Dec. 31, 2012
Assets
Cash and cash equivalents	$ 11,707	$ 57,899
Investment securities, available-for-sale	174,083	50,068
Prepaid expenses, receivables and other current assets	2,570	581
Total current assets	188,360	108,548
Property and equipment, net	579	42
Other assets	179
Total assets	189,118	108,590
Liabilities, redeemable common stock and stockholders' equity
Accounts payable	372	1,375
Accrued expenses	6,552	4,139
Deferred revenue	55	434
Total current liabilities	6,979	5,948
Long-term liabilities	8
Total liabilities	6,987	5,948
Commitments and contingencies (Note 10)
Redeemable common stock, $0.0001 par value; no shares and 5,347,137 shares issued and outstanding at December 31, 2013 and 2012, respectively (Note 7)		17,658
Stockholders' equity
Preferred stock, $0.0001 par value; 5,000,000 shares authorized at December 31, 2013 and 2012; no shares issued and outstanding at December 31, 2013 and 2012
Common stock, $0.0001 par value; 150,000,000 shares authorized at December 31, 2013 and 2012; 91,102,618 shares and 73,334,216 shares issued and outstanding at December 31, 2013 and 2012, respectively	9	7
Additional paid-in capital	587,742	452,693
Accumulated deficit	(405,668)	(367,720)
Accumulated other comprehensive income	48	4
Total stockholders' equity	182,131	84,984
Total liabilities, redeemable common stock and stockholders' equity	$ 189,118	$ 108,590

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2013	Dec. 31, 2012
Statement Of Financial Position [Abstract]
Redeemable common stock, par value	$ 0.0001	$ 0.0001
Redeemable common stock, shares issued	0	5,347,137
Redeemable common stock, shares outstanding	0	5,347,137
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	91,102,618	73,334,216
Common stock, shares outstanding	91,102,618	73,334,216

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues
Collaborative revenues	$ 1,145	$ 4,907	$ 2,067
Operating expenses
Research and development (includes stock-based compensation of $2,208, $680, and $512, respectively)	26,722	18,794	17,309
General and administrative (includes stock-based compensation of $3,503, $1,250, and $1,086, respectively)	12,720	6,999	7,610
Total operating expenses	39,442	25,793	24,919
Loss from operations	(38,297)	(20,886)	(22,852)
Interest income, net	349	37	87
Net loss	$ (37,948)	$ (20,849)	$ (22,765)
Net loss per common share, basic and diluted	$ (0.44)	$ (0.38)	$ (0.44)
Weighted average common shares outstanding, basic and diluted	85,715	55,116	52,183

Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Research and development
Stock-based compensation	$ 2,208	$ 680	$ 512
General and administrative
Stock-based compensation	$ 3,503	$ 1,250	$ 1,086

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (37,948)	$ (20,849)	$ (22,765)
Other comprehensive loss:
Unrealized gain (loss) on investment securities	45	(4)	9
Foreign currency translation adjustments	(1)	(1)	(512)
Comprehensive loss	$ (37,904)	$ (20,854)	$ (23,268)

- Definition

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

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+ Details

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash flows from operating activities
Net loss	$ (37,948)	$ (20,849)	$ (22,765)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	5,711	1,930	1,598
Amortization of premiums on investment securities	1,528	(133)	105
Depreciation and amortization	79	109	285
Non-cash charge resulting from lease termination			806
Gain on sales of property and equipment	(10)	(252)
Changes in operating assets and liabilities:
Prepaid expenses, receivables and other current assets	(1,989)	320	(131)
Other assets	(179)	14	106
Accounts payable	(1,003)	(585)	(29)
Accrued expenses	2,413	635	277
Deferred revenue	(379)	(2,822)	(57)
Long-term liabilities	8		(92)
Net cash used in operating activities	(31,769)	(21,633)	(19,897)
Cash flows from investing activities
Purchases of investment securities	(211,585)	(56,728)	(48,066)
Maturities of investment securities	86,087	30,948	54,049
Purchases of property and equipment	(618)		(3)
Proceeds from sales of property and equipment	12	252
Net cash (used in) provided by investing activities	(126,104)	(25,528)	5,980
Cash flows from financing activities
Proceeds from issuances of equity securities, net of issuance costs	111,682	98,204	14,022
Repayments of long-term debt		(32)	(78)
Net cash provided by financing activities	111,682	98,172	13,944
Effect of exchange rate changes on cash	(1)	(1)	13
Net (decrease) increase in cash and cash equivalents	(46,192)	51,010	40
Cash and cash equivalents
Beginning of year	57,899	6,889	6,849
End of year	11,707	57,899	6,889
Supplemental schedule of noncash investing activities
Unrealized gain (loss) on investment securities	$ 45	$ (4)	$ 9

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Dec. 31, 2010		39,350,561
Beginning balance at Dec. 31, 2010	$ 29,688	$ 4	$ 353,278	$ (324,106)	$ 512
Issuance of common stock and warrants, net of issuance costs (in shares)		12,565,446
Issuance of common stock and warrants, net of issuance costs	13,900	$ 1	13,899
Issuance of common stock from exercise of stock options (in shares)		10,434
Issuance of common stock from exercise of stock options	$ 13		13
Issuance of common stock pursuant to employee stock purchase plan (in shares)	189,879	189,879
Issuance of common stock pursuant to employee stock purchase plan	$ 109		109
Issuance of common stock in connection with lease termination (in shares)		782,339
Issuance of common stock in connection with lease termination	1,322		1,322
Net loss	(22,765)			(22,765)
Stock-based compensation	1,598		1,598
Other comprehensive income (loss)	(503)				(503)
Ending balance (in shares) at Dec. 31, 2011		52,898,659
Ending balance at Dec. 31, 2011	23,362	$ 5	370,219	(346,871)	9
Issuance of common stock and warrants, net of issuance costs (in shares)		19,000,000
Issuance of common stock and warrants, net of issuance costs	80,538	$ 2	80,536
Issuance of common stock from exercise of stock options (in shares)		293,595
Issuance of common stock from exercise of stock options	$ 453		453
Issuance of common stock pursuant to employee stock purchase plan (in shares)	205,862	205,862
Issuance of common stock pursuant to employee stock purchase plan	$ 123		123
Issuance of common stock from exercise of warrants on a net issuance basis (in shares)	874,719	936,100
Issuance of common stock from exercise of warrants on a net issuance basis
Issuance of common stock under ATM Agreement, net of issuance costs (in shares)		5,347,137
Issuance of common stock under ATM Agreement, net of issuance costs	17,090	$ 1	17,089
Reclassification to redeemable common stock (in shares)		(5,347,137)
Reclassification to redeemable common stock	(17,658)	$ (1)	(17,657)
Net loss	(20,849)			(20,849)
Stock-based compensation	1,930		1,930
Other comprehensive income (loss)	(5)				(5)
Ending balance (in shares) at Dec. 31, 2012		73,334,216
Ending balance at Dec. 31, 2012	84,984	$ 7	452,693	(367,720)	4
Issuance of common stock in public offering, net of issuance costs (in shares)		9,200,000
Issuance of common stock in public offering, net of issuance costs	$ 107,883	$ 1	107,882
Issuance of common stock from exercise of stock options (in shares)	1,455,406	1,455,406
Issuance of common stock from exercise of stock options	$ 3,441		3,441
Issuance of common stock pursuant to employee stock purchase plan (in shares)	122,853	122,853
Issuance of common stock pursuant to employee stock purchase plan	$ 358		358
Issuance of common stock from exercise of warrants on a net issuance basis (in shares)	1,643,006	1,643,006
Issuance of common stock from exercise of warrants on a net issuance basis
Reclassification from redeemable common stock (in shares)		5,347,137
Reclassification from redeemable common stock	17,658	$ 1	17,657
Net loss	(37,948)			(37,948)
Stock-based compensation	5,711		5,711
Other comprehensive income (loss)	44				44
Ending balance (in shares) at Dec. 31, 2013		91,102,618
Ending balance at Dec. 31, 2013	$ 182,131	$ 9	$ 587,742	$ (405,668)	$ 48

Organization and Nature of Operations	12 Months Ended
Organization and Nature of Operations	Dec. 31, 2013
Accounting Policies [Abstract]
Organization and Nature of Operations	1. Organization and Nature of Operations ACADIA Pharmaceuticals Inc. (the “Company”) was originally incorporated in Vermont in 1993 as Receptor Technologies, Inc. The Company reincorporated in Delaware in 1997 and its operations are based in San Diego, California. The Company is focused on the development and commercialization of innovative small molecule drugs that address unmet medical needs in neurological and related central nervous system disorders. The Company has incurred substantial operating losses since its inception due in large part to expenditures for its research and development activities. As of December 31, 2013, the Company had an accumulated deficit of $405.7 million. The Company expects to continue to incur operating losses for at least the next several years as it pursues the development and commercialization of its product candidates. The Company will require significant additional financing in the future to fund its operations. Future capital requirements will depend on many factors, including the progress in, the outcome of and the costs of the Company’s development and regulatory activities, costs associated with establishing necessary sales and marketing capabilities, the scope, prioritization and number of its research and development programs, the ability of its collaborators and the Company to reach milestones and other events or developments under its collaboration and license agreements, and the ability of the Company to enter into new, and to maintain existing, collaboration and license agreements. Until the Company can generate significant continuing revenues, it expects to fund its operations through its existing cash, cash equivalents and investment securities, payments from existing and potential future collaborations, proceeds from public or private sales of its equity securities, debt financing, grant funding, or by licensing all or a portion of its product candidates or technology. The Company cannot be certain that adequate additional funding will be available on acceptable terms, or at all. Conditions in the financial markets and other factors could have a material adverse effect on the Company’s ability to access sufficient funding on acceptable terms, or at all. If the Company cannot raise adequate additional capital, it will be required to delay, further reduce the scope of, or eliminate one or more of its research or development programs or its commercialization efforts. In such circumstances, the Company may also be required to relinquish greater, or even all, rights to product candidates at earlier stages of development or on less favorable terms than it would otherwise choose.

- Definition

The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.

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+ Details

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2013

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Significant accounting policies followed in the preparation of these financial statements are as follows:

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiary located in Europe. All intercompany accounts and transactions have been eliminated in consolidation.

Cash and Cash Equivalents

The Company considers all highly liquid investments with an initial maturity date at the date of purchase of three months or less to be cash equivalents.

Investment Securities

Investment securities are considered to be available-for-sale and are carried at fair value. Unrealized gains and losses, if any, are reported as a separate component of stockholders’ equity. The cost of investment securities classified as available-for-sale is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion are included in interest income. Realized gains and losses, if any, are also included in interest income. The cost of securities sold is based on the specific identification method.

Fair Value of Financial Instruments

For financial instruments, consisting of cash and cash equivalents, accounts payable and accrued expenses included in the Company’s financial statements, the carrying amounts are reasonable estimates of fair value due to their short maturities. Estimated fair values for investment securities, which are separately disclosed elsewhere, are based on quoted market prices for the instruments or other observable inputs.

Property and Equipment

Property and equipment are recorded at cost and depreciated over their estimated useful lives (generally three to ten years) using the straight line method. Leasehold improvements are amortized over the shorter of their estimated useful lives or the term of the lease by use of the straight line method. Maintenance and repair costs are expensed as incurred. When assets are retired or sold, the assets and accumulated depreciation are removed from the respective accounts and any gain or loss is recognized.

Revenues

The Company recognizes revenues in accordance with authoritative guidance established by U.S. generally accepted accounting principles (“GAAP”). The Company’s revenues are primarily related to its collaboration agreements, which may provide for various types of payments, including upfront payments, funding of research and development, milestone payments, and licensing fees. The Company’s collaboration agreements also include potential payments for product royalties; however, the Company has not received any product royalties to date.

The Company considers a variety of factors in determining the appropriate method of accounting under its collaboration agreements, including whether the various elements can be separated and accounted for individually as separate units of accounting. Where there are multiple deliverables identified within a collaboration agreement that are combined into a single unit of accounting, revenues are deferred and recognized over the expected period of performance. The specific methodology for the recognition of the revenue is determined on a case-by-case basis according to the facts and circumstances of the applicable agreement.

Upfront, non-refundable payments that do not have stand-alone value are recorded as deferred revenue once received and recognized as revenues over the expected period of performance. Revenues from non-refundable license fees are recognized upon receipt of the payment if the license has stand-alone value, the Company does not have ongoing involvement or obligations, and the Company can determine the best estimate of the selling price for any undelivered items. When non-refundable license fees do not meet all of these criteria, the license revenues are recognized over the expected period of performance. Non-refundable payments for research funding are generally recognized as revenues over the period the related research activities are performed. Payments for reimbursement of external development costs are generally recognized as revenues using a contingency-adjusted performance model over the expected period of performance. Payments received from grants are recognized as revenues as the related research and development is performed and when collectability has been reasonably assured.

The Company evaluates milestone payments on an individual basis and recognizes revenues from non-refundable milestone payments when the earnings process is complete and collectability is reasonably assured. Non-refundable milestone payments related to arrangements under which the Company has continuing performance obligations are recognized as revenues upon achievement of the associated milestone, provided that (i) the milestone event is substantive and its achievability was not reasonably assured at the inception of the agreement and (ii) the amount of the milestone payment is reasonable in relation to the effort expended or the risk associated with the milestone event. Where separate milestone payments do not meet these criteria, the Company recognizes revenue using a contingency-adjusted performance model over the expected period of performance.

Research and Development Expenses

Research and development expenses are charged to operations as incurred. Research and development expenses include, among other things, costs associated with services provided by contract organizations for preclinical development, manufacturing of product candidates, and clinical trials. The Company accrues for costs incurred as the services are being provided by monitoring the status of the trial or services provided and the invoices received from its external service providers. In the case of clinical trials, a portion of the estimated cost normally relates to the projected cost to treat a patient in the trials, and this cost is recognized based on the number of patients enrolled in the trial. Other indirect costs are generally recognized on a straight-line basis over the estimated period of the study. As actual costs become known, the Company adjusts its accruals. Certain research and development programs are funded under agreements with collaboration partners, and the Company’s costs related to these activities are included in research and development expenses.

Concentrations of Risk

Financial instruments, which potentially subject the Company to concentrations of credit risk, principally consist of cash, cash equivalents, and investment securities. The Company currently invests its excess cash primarily in a money market fund, U.S. Treasury notes, and high quality, marketable debt instruments of corporations, financial institutions and government sponsored enterprises. The Company has adopted an investment policy that includes guidelines relative to credit quality, diversification and maturities to preserve principal and liquidity.

During the years ended December 31, 2013, 2012 and 2011, revenues from the Company’s agreements with certain collaborative partners exceeded 10 percent of its total revenues. During the year ended December 31, 2013, revenues from Allergan, Inc., the National Institutes of Health, and The Michael J. Fox Foundation comprised 50 percent, 19 percent, and 15 percent of total revenues, respectively. During the year ended December 31, 2012, revenues from Allergan and Meiji Seika Pharma Co., Ltd. (“Meiji Seika Pharma”) comprised 23 percent and 66 percent of total revenues, respectively. During the year ended December 31, 2011, revenues from Allergan, Meiji Seika Pharma and The Michael J. Fox Foundation comprised 52 percent, 25 percent and 13 percent of total revenues, respectively.

Stock-Based Compensation

The fair value of each employee stock option and each employee stock purchase right granted is estimated on the grant date under the fair value method using the Black-Scholes model. The estimated fair value of each stock option and purchase right, including the effect of estimated forfeitures, is then expensed over the vesting period. The following assumptions were used to estimate the fair value of employee stock options:


	Years Ended December 31,
	2013			2012			2011
Expected volatility		94	%		98-99	%		98	%
Risk-free interest rate		1-2	%		1	%		1-2	%
Expected forfeiture rate		8	%		9	%		10	%
Expected dividend yield		0	%		0	%		0	%
Expected life of options in years		6.0			5.8-6.0			5.8

Expected Volatility. The Company considers its historical volatility and implied volatility when determining the expected volatility.

Risk-Free Interest Rate. The risk-free interest rate is based on the implied yield currently available on U.S. Treasury zero-coupon issues with a remaining term approximating the expected term of the option.

Expected Forfeiture Rate. The Company considers its pre-vesting forfeiture history to determine its expected forfeiture rate.

Expected Dividend Yield. The Company has never paid any dividends and currently has no plans to do so.

Expected Life of Options. The Company considers, among other factors, its historical exercise experience to date as well as the mean time remaining to full vesting of all outstanding options and the mean time remaining to the end of the contractual term of all outstanding options.

The following assumptions were used to estimate the fair value of the purchase rights of each offering under the employee stock purchase plan that commenced during the indicated year:


	Years Ended December 31,
	2013			2012			2011
Expected volatility		69-118	%		69-137	%		64-111	%
Risk-free interest rate		0.1-0.3	%		0.1-0.3	%		0.1-0.4	%
Expected dividend yield		0	%		0	%		0	%
Expected life of offering in years		0.5-2.0			0.5-2.0			0.5-2.0

Income Taxes

Current income tax expense or benefit represents the amount of income taxes expected to be payable or refundable for the current year. A deferred income tax asset or liability is computed for the expected future impact of differences between the financial reporting and income tax bases of assets and liabilities and for the expected future tax benefit to be derived from tax credits and loss carryforwards. Deferred income tax expense or benefit represents the net change during the year in the deferred income tax asset or liability. Deferred tax assets are reduced by a valuation allowance when, in the opinion of management, it is more likely than not that some portion or all of the deferred tax assets will not be realized.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates.

Long-Lived Assets

The Company assesses potential impairments to its long-lived assets when there is evidence that events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. An impairment loss is recognized when the estimated undiscounted cash flows expected to result from the use of the asset and its eventual disposition is less than its carrying amount. The amount of the impairment loss, if any, will generally be measured as the difference between the net book value of the assets and their estimated fair values. No such impairment losses have been recorded by the Company.

Comprehensive Income (Loss)

All components of comprehensive income (loss), including net income (loss), are reported in the financial statements in the period in which they are recognized. Comprehensive income (loss) is defined as the change in equity (net assets) of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. In accordance with accounting guidance, the Company presents the impact of any fluctuations in its foreign currency translation adjustments and any unrealized gains or losses on its investment securities in a separate statement of comprehensive income (loss) for each period.

Net Income (Loss) Per Common Share

Basic earnings (loss) per common share is computed by dividing net income (loss) by the weighted average number of common shares outstanding for the period. Diluted earnings (loss) per common share is computed by dividing net income (loss) by the weighted average number of common shares outstanding during the period, increased to include potential dilutive common shares that were outstanding during the period. The effect of outstanding stock options and warrants is reflected, when dilutive, in diluted earnings per common share by application of the treasury stock method. The Company has excluded all outstanding stock options and warrants from the calculation of diluted net loss per common share for the years ended December 31, 2013, 2012 and 2011 because all such securities were antidilutive. Shares used in calculating basic and diluted net loss per common share exclude these potential common shares:


	Years Ended December 31,
	2013		2012		2011
	(in thousands)
Antidilutive options to purchase common stock		7,245		6,868		5,414
Antidilutive warrants to purchase common stock		3,116		4,388		4,559

		10,361		11,256		9,973

Segment Reporting

Management has determined that the Company operates in one business segment. All revenues for the years ended December 31, 2013, 2012 and 2011 were generated in the United States.

Recently Issued Accounting Standards

In July 2013, the FASB issued authoritative guidance regarding the presentation of unrecognized tax benefits when a net operating loss carryforward exists. This authoritative guidance amends current guidance. The amended guidance clarifies that an unrecognized tax benefit, or a portion of an unrecognized tax benefit, should be presented in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward if such settlement is required or expected in the event the uncertain tax position is disallowed. In situations where a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date under the tax law of the applicable jurisdiction or the tax law of the jurisdiction does not require, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. This amended guidance is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2013. The Company is evaluating the impact, if any, this guidance will have on its consolidated financial statements.

Investment Securities

12 Months Ended

Dec. 31, 2013

Investments Debt And Equity Securities [Abstract]

Investment Securities

3. Investment Securities

Investment securities included investment securities available-for-sale and, at December 31, 2012, investment securities classified as cash equivalents. Investment securities consisted of the following:


	December 31, 2013
	Amortized Cost		Unrealized Gains		Unrealized (Losses)			Estimated Fair Value
	(in thousands)
U.S. Treasury notes	$	2,743	$	4	$	—		$	2,747
Government sponsored enterprise securities		78,537		28		(5	)		78,560
Corporate debt securities		65,290		1		(9	)		65,282
Commercial paper		27,468		26		—			27,494

	$	174,038	$	59	$	(14	)	$	174,083


	December 31, 2012
	Amortized Cost		Unrealized Gains		Unrealized (Losses)			Estimated Fair Value
	(in thousands)
U.S. Treasury notes	$	2,029	$	1	$	—		$	2,030
Government sponsored enterprise securities		54,353		4		(5	)		54,352

	$	56,382	$	5	$	(5	)	$	56,382

The Company has classified all of its investments securities available-for-sale, including those with maturities beyond one year, as current assets on the consolidated balance sheets based on the highly liquid nature of the investment securities and because these investment securities are considered available for use in current operations. As of December 31, 2013 and 2012, the Company held $33.5 million and $14.2 million, respectively, of available-for-sale investment securities with contractual maturity dates more than one year and less than two years.

- Definition

The entire disclosure for investments in certain debt and equity securities.

+ References + Details

Fair Value Measurements

12 Months Ended

Dec. 31, 2013

Fair Value Disclosures [Abstract]

Fair Value Measurements

4. Fair Value Measurements

As of December 31, 2013, the Company held $185.8 million of cash equivalents and available-for-sale investment securities consisting of a money market fund, U.S. Treasury notes, and high quality, marketable debt instruments of corporations, financial institutions and government sponsored enterprises. The Company has adopted an investment policy and established guidelines relating to credit quality, diversification and maturities of its investments to preserve principal and maintain liquidity. All investment securities have a credit rating of at least A3/A- or better, or P-1/A-1 or better, as determined by Moody’s Investors Service or Standard & Poor’s.

The Company’s cash equivalents and available-for-sale investment securities are classified within the fair value hierarchy as defined by authoritative guidance. The Company’s investment securities classified as Level 1 are valued using quoted market prices and the Company’s investment securities classified as Level 2 are valued using other observable inputs such as recent trades for the securities or similar securities, interest rates on similar securities, or yield curves or benchmark interest rates observable at commonly quoted intervals. The Company does not hold any securities classified as Level 3, which are securities valued using unobservable inputs. The Company has not transferred any investment securities between the classifications. No other-than-temporary impairments were identified for the investment securities held by the Company as of December 31, 2013 or December 31, 2012.

The fair value measurements of the Company’s cash equivalents and available-for-sale investment securities are identified in the following tables (in thousands):


			Fair Value Measurements at Reporting Date Using
	December 31, 2013		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Money market fund	$	11,748	$	11,748	$	—	$	—
U.S. Treasury notes		2,747		2,747		—		—
Government sponsored enterprise securities		78,560		—		78,560		—
Corporate debt securities		65,282		—		65,282		—
Commercial paper		27,494		—		27,494		—

	$	185,831	$	14,495	$	171,336	$	—


			Fair Value Measurements at Reporting Date Using
	December 31, 2012		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Money market fund	$	51,216	$	51,216	$	—	$	—
U.S. Treasury notes		2,030		2,030		—		—
Government sponsored enterprise securities		54,352		—		54,352		—

	$	107,598	$	53,246	$	54,352	$	—

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Balance Sheet Components

12 Months Ended

Dec. 31, 2013

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Balance Sheet Components

5. Balance Sheet Components

Property and equipment, net, consisted of the following:


	Estimated Useful Lives (Years)	December 31,
	Estimated Useful Lives (Years)	2013			2012
		(in thousands)
Machinery and equipment	5–7	$	875		$	2,578
Computers and software	3		863			981
Leasehold improvements	3–10		570			1,057
Furniture and fixtures	3–10		245			159

			2,553			4,775
Accumulated depreciation and amortization			(1,974	)		(4,733	)

		$	579		$	42

Depreciation and amortization of property and equipment was $79,000, $109,000, and $285,000 for the years ended December 31, 2013, 2012, and 2011, respectively. During 2013, the Company retired $2.8 million of fully depreciated property and equipment. During 2012, the Company sold $1.5 million of fully depreciated machinery and equipment for a gain of $252,000.

Accrued expenses consisted of the following:


	December 31,
	2013		2012
	(in thousands)
Accrued research and development services	$	4,207	$	3,216
Accrued compensation and benefits		1,865		413
Accrued professional fees		308		364
Other		172		146

	$	6,552	$	4,139

Collaborative Research and Licensing Agreements	12 Months Ended
Collaborative Research and Licensing Agreements	Dec. 31, 2013
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Collaborative Research and Licensing Agreements	6. Collaborative Research and Licensing Agreements The Company has been a party to three collaboration agreements with Allergan. The March 2003 collaboration originally provided for a three-year research term, which was extended by the parties through March 2013. Pursuant to this agreement, the Company received an aggregate of $19.5 million in payments, consisting of an upfront payment, research funding and related fees, through the conclusion of the collaboration in March 2013. The Company’s two ongoing collaboration agreements with Allergan involve the development of product candidates in the areas of glaucoma and chronic pain. Under the glaucoma collaboration, the Company had received an aggregate of $9.9 million in payments as of December 31, 2013, and is eligible to receive up to an aggregate of approximately $15 million in additional payments per product upon the achievement of development and regulatory milestones. Under the chronic pain collaboration, the Company had received an aggregate of $10.5 million in payments as of December 31, 2013, and is eligible to receive up to an aggregate of $10 million in additional payments upon the achievement of development and regulatory milestones. The Company also is eligible to receive royalties on future product sales worldwide, if any, under each of the two ongoing collaboration agreements with Allergan. The Company recognized revenues, consisting of research funding, milestone and related fees, from its collaboration agreements with Allergan of $571,000, $1.1 million and $1.1 million during each of the years ended December 31, 2013, 2012, and 2011. In March 2009, the Company entered into a collaboration agreement with Meiji Seika Pharma. In July 2012, the Company and Meiji Seika Pharma jointly decided to discontinue the development program that was being pursued under the collaboration, and the collaboration agreement was terminated pursuant to its terms. Under the collaboration agreement, the Company had received $3 million in non-refundable license fees as well as payments for the reimbursement of development costs that it had incurred during the collaboration. Payments received from Meiji Seika Pharma were deferred and recognized as revenues using a contingency-adjusted performance model over the estimated period of the Company’s performance. Upon the termination of this collaboration agreement and the end of the Company’s related performance obligations, the Company recognized as revenue the remaining deferred revenue from this collaboration during the third quarter of 2012. The Company recognized revenues relating to this collaboration of $3.2 million and $505,000 during the years ended December 31, 2012 and 2011, respectively. Effective January 1, 2011, the Company prospectively adopted authoritative guidance for any new, or materially modified, multiple deliverable arrangement after the date of adoption. The Company has not entered into any new, or materially modified any, multiple deliverable arrangements since January 1, 2011. Accordingly, the collaborative agreements discussed above in this note that contain multiple deliverables continue to be accounted for under previously issued revenue recognition guidance for multiple deliverable arrangements. Under this prior guidance, the Company recognizes revenue for non-refundable payments upon receipt of the payment if the deliverable has stand-alone value, the Company does not have ongoing involvement or obligations, and the fair value of any undelivered items can be determined. When non-refundable payments for deliverables do not meet all of these criteria, the payment is deferred and revenues are recognized over the expected period of performance. For a discussion of the Company’s revenue recognition policy that would apply to any future multiple deliverable arrangement, see Note 2—Summary of Significant Accounting Policies—Revenues.

Stockholders' Equity

12 Months Ended

Dec. 31, 2013

Equity [Abstract]

Stockholders' Equity

7. Stockholders’ Equity

Public Offering

In May 2013, the Company raised net proceeds of $107.9 million from the sale of 9,200,000 shares of its common stock in a public offering, including 1,200,000 shares sold pursuant to the exercise in full of the underwriters’ over-allotment option.

Private Equity Financings

In December 2012, the Company raised net proceeds of $80.5 million through the sale of 19,000,000 shares of its common stock at a price of $4.43 per share and the sale of warrants to purchase 500,000 shares of its common stock at a price of $4.42 per warrant share in a private equity financing. The warrants have an exercise price of $0.01 per share and will expire on December 17, 2019. In accordance with authoritative accounting guidance, the warrants’ value of $2.2 million was determined on the date of grant using the Black-Scholes model with the following assumptions: risk free interest rate of 1.1 percent, volatility of 105.8 percent, a 7.0 year term and no dividend yield. These warrants were recorded as a component of stockholders’ equity within additional paid-in capital. Per their terms, the outstanding warrants to purchase 500,000 shares of common stock may not be exercised if the holder’s ownership of the Company’s common stock would exceed 19.99 percent following such exercise. Pursuant to the terms of the private financing, the Company has an effective resale registration statement on file with the SEC covering shares of common stock sold and shares of common stock issuable upon the exercise of the warrants.

In January 2011, the Company raised net proceeds of $13.9 million through the sale of 12,565,446 units at a price of $1.19375 per unit in a private equity financing. Each unit consisted of one share of the Company’s common stock and a warrant to purchase 0.35 shares of common stock. The warrants have an exercise price of $1.38 per share and will expire on January 11, 2018. In accordance with authoritative accounting guidance, the warrants’ value of $3.3 million was determined on the date of grant using the Black-Scholes model with the following assumptions: risk free interest rate of 2.8 percent, volatility of 99.0 percent, a 7.0 year term and no dividend yield. These warrants were recorded as a component of stockholders’ equity with an equal offsetting amount to stockholders’ equity because the value of the warrants was considered a financing cost. During the year ended December 31, 2013, warrants to purchase 1,759,162 shares of common stock were exercised on a net issuance basis, resulting in the issuance of 1,643,006 shares of common stock. During the year ended December 31, 2012, warrants to purchase 1,172,774 shares of common stock were exercised on a net issuance basis, resulting in the issuance of 874,719 shares of common stock. At December 31, 2013, warrants to purchase 1,465,968 shares of common stock remained outstanding. Pursuant to the terms of the private financing, the Company has an effective resale registration statement on file with the SEC covering shares of common stock sold and shares of common stock issuable upon the exercise of the warrants.

Other Financing Transactions

In March 2012, the Company entered into an At-The-Market Issuance Sales Agreement (“ATM Agreement”) with MLV & Co. LLC. During the year ended December 31, 2012, the Company raised gross proceeds of $17.7 million from the sale of 5,347,137 shares of common stock under the ATM Agreement, resulting in net proceeds of $17.1 million after issuance costs. In November 2012, the Company determined that it had failed to timely file a Current Report on Form 8-K to report the election of a new director in January 2012. As a result, the Company was ineligible to use its effective shelf registration statement on Form S-3. Therefore, sales of the Company’s common stock made pursuant to the ATM Agreement in 2012 and issued under the registration statement were subject to potential rescission rights that expired in 2013. No shareholder claimed or attempted to exercise any such rights. At December 31, 2012, the Company classified 5.3 million shares ($17.7 million) of its common stock outside stockholders’ equity because the potential redemption features were not within the control of the Company. These shares were treated as outstanding for financial reporting purposes.

Stock Option Plans

The Company’s 2010 Equity Incentive Plan (the “2010 Plan”) permits the grant of options to directors, officers, other employees, and consultants. In addition, the 2010 Plan permits the grant of stock bonuses, rights to purchase restricted stock, and other stock awards. The exercise price of options granted under the 2010 Plan cannot be less than 100 percent of the fair market value of the common stock on the date of grant and the maximum term of any option is ten years. Options granted under the 2010 Plan generally vest over a four-year period. All shares that remained eligible for grant under the Company’s 2004 Equity Incentive Plan (the “2004 Plan”) at the time of approval of the 2010 Plan were transferred to the 2010 Plan. The 2010 Plan share reserve also has been, and may be, increased by the number of shares that otherwise would have reverted to the 2004 Plan reserve after June 2010. At December 31, 2013, there were 14,048,237 shares of common stock authorized for issuance and 6,710,099 shares of common stock available for new grants under the 2010 Plan.

The 2004 Plan provided for the grant of options to directors, officers, other employees, and consultants. The exercise price of options granted under the 2004 Plan was at 100 percent of the fair market value of the common stock on the date of grant and the maximum term of any option was ten years. Options granted under the 2004 Plan generally vested over a four-year period. The Company’s 1997 stock option plan (the “1997 Plan”) provided for the grant of options to directors, officers, other employees, and consultants prior to the Company’s initial public offering. The exercise price of each option grant was set at the fair market value for the Company’s common stock as determined by the Company’s Board of Directors and each option’s maximum term was ten years. Options granted under the 1997 Plan generally vested over a four-year period.

Stock option transactions during the year ended December 31, 2013 are presented below:


	Number of Shares			Weighted- Average Exercise Prices		Weighted Average Remaining Contractual Term
Outstanding at January 1, 2013		6,948,456		$	3.08
Granted		1,954,500		$	16.68
Exercised		(1,455,406	)	$	2.36
Canceled/forfeited		(109,412	)	$	5.04

Outstanding at December 31, 2013		7,338,138		$	6.81		7.1

Vested and expected to vest at December 31, 2013		7,034,407		$	6.53		7.0

Exercisable at December 31, 2013		4,314,480		$	3.79		5.9

The aggregate intrinsic value of options outstanding and exercisable as of December 31, 2013, is calculated as the difference between the exercise price of the underlying options and the closing market price of the Company’s common stock on that date, which was $24.99. The aggregate intrinsic value of options outstanding and exercisable as of December 31, 2013, was $91.5 million. The aggregate intrinsic value of options exercised during the years ended December 31, 2013, 2012, and 2011 was approximately $20.7 million, $650,000, and $6,000, respectively, determined as of the date of exercise. The Company received $3.4 million in cash from options exercised during the year ended December 31, 2013.

The weighted average fair value of options granted during the years ended December 31, 2013, 2012, and 2011 was approximately $12.66, $1.51, and $1.25, respectively. As of December 31, 2013, total unrecognized compensation cost related to stock options and purchase rights was approximately $20.0 million, and the weighted average period over which this cost is expected to be recognized is 2.7 years.

The following table summarizes information about stock options outstanding at December 31, 2013:


Options Outstanding					Options Exercisable
Range of Exercise Prices	Number of Shares		Weighted- Average Remaining Contractual Life	Weighted- Average Exercise Price	Number of Shares		Weighted- Average Exercise Price
$0.96–$ 1.56		1,589,996	6.9	$1.42		1,405,676	$1.43
$1.57–$ 1.86		1,273,411	7.3	$1.65		913,487	$1.66
$1.87–$ 2.39		1,443,343	7.3	$2.14		842,284	$2.11
$2.40–$14.89		1,275,608	4.3	$8.09		971,503	$8.45
$14.90–$27.47		1,755,780	9.0	$18.36		181,530	$15.61

		7,338,138		$6.81		4,314,480	$3.79

Stock-based awards issued to non-employees other than directors are accounted for using a fair value method and are re-measured to fair value at each period end until the earlier of the date that performance by the non-employee is complete or a performance commitment has been obtained. The fair value of each award is estimated using the Black-Scholes option pricing model with the following assumptions for the year ended December 31, 2013: dividend yield of 0 percent; volatility of 93 to 95 percent; risk free interest rate of 2 to 3 percent and remaining contractual life of 7 to 10 years. The stock compensation expense related to the grant of stock options to non-employees was $584,000 for the year ended December 31, 2013 and was not significant for each of the years ended December 31, 2012 and 2011.

Employee Stock Purchase Plan

The Company’s 2004 Employee Stock Purchase Plan (the “Purchase Plan”) became effective upon the closing of the Company’s initial public offering in June 2004. The Purchase Plan includes an “evergreen” provision providing that an additional number of shares may be added to the shares authorized for issuance on the date of each annual meeting of stockholders for a period of ten years, which began with the meeting in 2005. Through December 31, 2013, a total of 1,375,000 shares of common stock had been reserved for issuance under the Purchase Plan. At December 31, 2013, 333,400 shares of common stock remained available for issuance pursuant to the Purchase Plan. Eligible employees who elect to participate in an offering under the Purchase Plan may have up to 15 percent of their earnings withheld, subject to certain limitations, to purchase shares of common stock pursuant to the Purchase Plan. The price of common stock purchased under the Purchase Plan is equal to 85 percent of the lower of the fair market value of the common stock at the commencement date of each offering period or the relevant purchase date. During the years ended December 31, 2013, 2012, and 2011, a total of 122,853, 205,862, and 189,879 shares of common stock were issued under the Purchase Plan at average prices of $2.92, $0.60, and $0.57, respectively. The weighted average fair value of purchase rights granted during the years ended December 31, 2013, 2012, and 2011 was $10.96, $2.43, and $0.67, respectively. During the years ended December 31, 2013, 2012, and 2011, the Company recorded cash received from the exercise of purchase rights of $358,000, $123,000, and $109,000, respectively.

Common Stock Reserved for Future Issuance

At December 31, 2013, a total of 7,338,138 and 1,965,968 shares of common stock were reserved for issuance pursuant to outstanding stock options and warrants, respectively.

- 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))
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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
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-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 4.E)
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21488-112644

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29-31)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Subparagraph (SAB TOPIC 4.C)
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23285-112656

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Preferred Stock
-URI http://asc.fasb.org/extlink&oid=6521494

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph d
-Article 4

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30, 31
-Article 5

Reference 16: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section E

Reference 17: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
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Reference 18: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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Reference 19: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

+ Details

401(k) Plan	12 Months Ended
401(k) Plan	Dec. 31, 2013
Compensation And Retirement Disclosure [Abstract]
401(k) Plan	8. 401(k) Plan Effective January 1997, the Company established a deferred compensation plan (the “401(k) Plan”) pursuant to Section 401(k) of the Internal Revenue Code of 1986, as amended (the “Code”), whereby substantially all employees are eligible to contribute up to 60 percent of their pretax earnings, not to exceed amounts allowed under the Code. The Company makes discretionary contributions to the 401(k) Plan equal to 100 percent of each employee’s pretax contributions up to 5 percent of his or her eligible compensation, subject to limitations under the Code. The Company’s total contributions to the 401(k) Plan were $240,000, $180,000, and $156,000 for the years ended December 31, 2013, 2012 and 2011, respectively.

Income Taxes

12 Months Ended

Dec. 31, 2013

Income Tax Disclosure [Abstract]

Income Taxes

9. Income Taxes

At December 31, 2013, the Company had both federal and state net operating loss (“NOL”) carryforwards of approximately $360.9 million and $332.5 million, respectively. Utilization of the NOL and research and development (“R&D”) credit carryforwards may be subject to a substantial annual limitation due to ownership change limitations that have occurred or that could occur in the future, as required by Section 382 of the Code, as well as similar state and foreign provisions. These ownership changes may limit the amount of NOL and R&D credit carryforwards that can be utilized annually to offset future taxable income and tax, respectively. In general, an “ownership change” as defined by Section 382 of the Code results from a transaction or series of transactions over a three-year period resulting in an ownership change of more than 50 percentage points of the outstanding stock of a company by certain stockholders or public groups.

The Company completed a study to assess whether an ownership change, as defined by Section 382 of the Code, had occurred from the Company’s formation through December 31, 2013. Based upon this study, the Company determined that several ownership changes had occurred. Accordingly, the Company has reduced its deferred tax assets related to the federal and state NOL carryforwards and the federal R&D credit carryforwards that are anticipated to expire unused as a result of these ownership changes. These tax attributes have been excluded from deferred tax assets with a corresponding reduction of the valuation allowance with no net effect on income tax expense or the effective tax rate. Future ownership changes may further limit the Company’s ability to utilize its remaining tax attributes.

Federal and state NOL carryforwards of $3.6 million and $7.5 million will expire in 2018 and 2014, respectively, unless utilized. The remaining federal and state NOL carryforwards will begin to expire in 2019 and 2015, respectively. At December 31, 2013, the Company had $8.0 million of federal R&D credit carryforwards of which $119,000 will expire in 2018 unless utilized, and the remaining federal R&D credit carryforwards will begin to expire in 2019. At December 31, 2013, the Company had $4.9 million of state R&D credit carryforwards that have no expiration date. At December 31, 2013, the Company also had foreign NOL carryforwards of approximately $4.1 million that have no expiration date. The Company continues to record the deferred tax assets related to these attributes, subject to valuation allowance, until expiration occurs.

Approximately $16.4 million of the NOL carryforwards relate to excess tax deductions for stock compensation, the income tax benefit of which will be recorded as additional paid-in capital if and when realized.

The components of the deferred tax assets are as follows:


	2013			2012
	(in thousands)
NOL carryforwards	$	136,583		$	127,894
R&D credit carryforwards		11,227			11,056
Capitalized R&D		8,003			4,075
Stock-based compensation		3,221			2,906
Other		1,207			775

		160,241			146,706
Valuation allowance		(160,241	)		(146,706	)

	$	—		$	—

Realization of deferred tax assets is dependent upon future earnings, if any, the timing and amount of which are uncertain. Accordingly, the deferred tax assets have been fully offset by a valuation allowance. The valuation allowance increased by $13.5 million in 2013 primarily due to an increase in deferred tax assets generated from net operating losses and R&D credits, partially offset by the expiration of NOL carryforwards in 2013.

A reconciliation of income taxes to the amount computed by applying the statutory federal income tax rate to the net loss is summarized as follows:


	2013			2012			2011
	(in thousands)
Amounts computed at statutory federal rate	$	(12,902	)	$	(7,088	)	$	(7,734	)
Stock-based compensation and other permanent differences		244			209			306
Reduction of deferred tax assets under Section 382 of the Code		2,781			—			—
R&D credits		(1,269	)		(937	)		(514	)
Change in valuation allowance		13,509			8,375			8,820
State taxes		(2,140	)		(1,171	)		(1,288	)
Foreign taxes		—			(4	)		59
Other		(223	)		616			368

	$	0		$	0		$	17

The net income tax expense for each of the years ended December 31, 2013, 2012 and 2011 is recorded in the Company’s statement of operations in general and administrative expenses.

The tax years 1998-2013 remain open to examination by the major taxing jurisdictions to which the Company is subject. During 2012, the Internal Revenue Service concluded an exam for tax years 2008 and 2009 that resulted in favorable adjustments to the Company’s R&D credits. As of December 31, 2013 and 2012, the Company did not have any liabilities recorded for uncertain tax positions.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2013

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

10. Commitments and Contingencies

The Company leases facilities and certain equipment under noncancelable operating leases that expire at various dates through December 2016. Under the terms of the facilities leases, the Company is required to pay its proportionate share of property taxes, insurance and normal maintenance costs.

Future noncancelable minimum payment obligations under operating lease arrangements were as follows at December 31, 2013:


Year Ending	(in thousands)
2014	$	838
2015		866
2016		583
2017		—
Thereafter		—

	$	2,287

Rent expense was $594,000, $663,000, and $2.1 million for the years ended December 31, 2013, 2012, and 2011, respectively. Facility operating leases contain escalation clauses. The Company recognizes rent expense on a straight line basis over the lease term. The difference between rent expense recorded and amounts paid under lease agreements is recorded as deferred rent.

In April 2011, the Company entered into a termination agreement related to the lease for its Swedish research facility and ceased operations at this site. The lease was entered into in June 2005 and had a 10-year term. Pursuant to this agreement, the Company made a one-time payment of $690,000 and issued 782,339 shares of its common stock to the landlord in settlement of all lease-related obligations. General and administrative expenses for the year ended December 31, 2011 included a net charge of $1.1 million, which amount consisted of $1.7 million in lease termination charges, offset by a $539,000 reduction in the Company’s cumulative translation adjustment balance related to the liquidation of substantially all assets of its Swedish subsidiary.

The Company has entered into agreements with contract research organizations and other external service providers primarily for services in connection with the development of its product candidates. The Company was contractually obligated for up to approximately $19.1 million of future services under these agreements as of December 31, 2013. The nature of the work being conducted under the Company’s agreements with contract research organizations is such that, in most cases, the services may be stopped with short notice. In such event, the Company would not be liable for the full amount of the contract. The Company’s actual contractual obligations may vary depending upon several factors, including the progress and results of the underlying studies.

In November 2006, the Company entered into an agreement with the Ipsen Group pursuant to which it licensed certain intellectual property rights that complement its patent portfolio for its serotonin platform, including pimavanserin. If certain conditions are met, the Company would be required to make future payments, including milestones, sublicensing fees and royalties. The amount of potential future milestones payments is $10.5 million in the aggregate, which amount would be offset by any sublicensing fees the Company may pay under the agreement. Because these milestone payments would only be payable upon the achievement of specified regulatory events and it is uncertain when, or if, such events will occur, the Company cannot forecast with any degree of certainty when, or if, it will be required to make payments under the agreement.

Selected Quarterly Financial Data (Unaudited)

12 Months Ended

Dec. 31, 2013

Quarterly Financial Information Disclosure [Abstract]

Selected Quarterly Financial Data (Unaudited)

11. Selected Quarterly Financial Data (Unaudited)


2013	March 31,			June 30,			September 30,			December 31,
	(in thousands, except per share data)
Revenues	$	417		$	451		$	240		$	37
Net loss	$	(6,123	)	$	(9,081	)	$	(10,695	)	$	(12,049	)
Net loss per common share, basic and diluted	$	(0.08	)	$	(0.11	)	$	(0.12	)	$	(0.13	)

2012	March 31,			June 30,			September 30,			December 31,
	(in thousands, except per share data)
Revenues	$	450		$	599		$	3,478		$	380
Net loss	$	(6,218	)	$	(5,419	)	$	(2,402	)	$	(6,810	)
Net loss per common share, basic and diluted	$	(0.12	)	$	(0.10	)	$	(0.04	)	$	(0.11	)

Revenues and net loss are rounded to thousands each quarter. Therefore, the sum of the quarterly amounts may not equal the annual amounts reported. Net loss per common share, basic and diluted, are computed independently for each quarter and the full year based upon respective average shares outstanding. Therefore, the sum of the quarterly net loss per common share amounts may not equal the annual amounts reported.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2013

Accounting Policies [Abstract]

Principles of Consolidation

Principles of Consolidation

Cash and Cash Equivalents

Cash and Cash Equivalents

The Company considers all highly liquid investments with an initial maturity date at the date of purchase of three months or less to be cash equivalents.

Investment Securities

Investment Securities

Fair Value of Financial Instruments

Fair Value of Financial Instruments

Property and Equipment

Property and Equipment

Revenues

Revenues

Research and Development Expenses

Research and Development Expenses

Concentrations of Risk

Concentrations of Risk

Stock-Based Compensation

Stock-Based Compensation


	Years Ended December 31,
	2013			2012			2011
Expected volatility		94	%		98-99	%		98	%
Risk-free interest rate		1-2	%		1	%		1-2	%
Expected forfeiture rate		8	%		9	%		10	%
Expected dividend yield		0	%		0	%		0	%
Expected life of options in years		6.0			5.8-6.0			5.8

Expected Volatility. The Company considers its historical volatility and implied volatility when determining the expected volatility.

Expected Forfeiture Rate. The Company considers its pre-vesting forfeiture history to determine its expected forfeiture rate.

Expected Dividend Yield. The Company has never paid any dividends and currently has no plans to do so.

The following assumptions were used to estimate the fair value of the purchase rights of each offering under the employee stock purchase plan that commenced during the indicated year:


	Years Ended December 31,
	2013			2012			2011
Expected volatility		69-118	%		69-137	%		64-111	%
Risk-free interest rate		0.1-0.3	%		0.1-0.3	%		0.1-0.4	%
Expected dividend yield		0	%		0	%		0	%
Expected life of offering in years		0.5-2.0			0.5-2.0			0.5-2.0

Income Taxes

Income Taxes

Use of Estimates

Use of Estimates

Long-Lived Assets

Long-Lived Assets

Comprehensive Income (Loss)

Comprehensive Income (Loss)

Net Income (Loss) Per Common Share

Net Income (Loss) Per Common Share


	Years Ended December 31,
	2013		2012		2011
	(in thousands)
Antidilutive options to purchase common stock		7,245		6,868		5,414
Antidilutive warrants to purchase common stock		3,116		4,388		4,559

		10,361		11,256		9,973

Segment Reporting

Segment Reporting

Management has determined that the Company operates in one business segment. All revenues for the years ended December 31, 2013, 2012 and 2011 were generated in the United States.

Recently Issued Accounting Standards

Recently Issued Accounting Standards

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2013

Accounting Policies [Abstract]

Assumptions Used to Estimate Fair Value of Employee Stock Options

The following assumptions were used to estimate the fair value of employee stock options:


	Years Ended December 31,
	2013			2012			2011
Expected volatility		94	%		98-99	%		98	%
Risk-free interest rate		1-2	%		1	%		1-2	%
Expected forfeiture rate		8	%		9	%		10	%
Expected dividend yield		0	%		0	%		0	%
Expected life of options in years		6.0			5.8-6.0			5.8

Assumptions Used to Estimate Fair Value Purchase Rights of Each Offering Under Employee Stock Purchase Plan

The following assumptions were used to estimate the fair value of the purchase rights of each offering under the employee stock purchase plan that commenced during the indicated year:


	Years Ended December 31,
	2013			2012			2011
Expected volatility		69-118	%		69-137	%		64-111	%
Risk-free interest rate		0.1-0.3	%		0.1-0.3	%		0.1-0.4	%
Expected dividend yield		0	%		0	%		0	%
Expected life of offering in years		0.5-2.0			0.5-2.0			0.5-2.0

Potential Common Shares Excluded in Calculating Basic and Diluted Net Loss Per Common Share

Shares used in calculating basic and diluted net loss per common share exclude these potential common shares:


	Years Ended December 31,
	2013		2012		2011
	(in thousands)
Antidilutive options to purchase common stock		7,245		6,868		5,414
Antidilutive warrants to purchase common stock		3,116		4,388		4,559

		10,361		11,256		9,973

Investment Securities (Tables)

12 Months Ended

Dec. 31, 2013

Investments Debt And Equity Securities [Abstract]

Investment Securities, Available-for-Sale and Classified as Cash Equivalents


	December 31, 2013
	Amortized Cost		Unrealized Gains		Unrealized (Losses)			Estimated Fair Value
	(in thousands)
U.S. Treasury notes	$	2,743	$	4	$	—		$	2,747
Government sponsored enterprise securities		78,537		28		(5	)		78,560
Corporate debt securities		65,290		1		(9	)		65,282
Commercial paper		27,468		26		—			27,494

	$	174,038	$	59	$	(14	)	$	174,083


	December 31, 2012
	Amortized Cost		Unrealized Gains		Unrealized (Losses)			Estimated Fair Value
	(in thousands)
U.S. Treasury notes	$	2,029	$	1	$	—		$	2,030
Government sponsored enterprise securities		54,353		4		(5	)		54,352

	$	56,382	$	5	$	(5	)	$	56,382

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2013

Fair Value Disclosures [Abstract]

Fair Value Measurements of Cash Equivalents and Available-For-Sale Investment Securities

The fair value measurements of the Company’s cash equivalents and available-for-sale investment securities are identified in the following tables (in thousands):


			Fair Value Measurements at Reporting Date Using
	December 31, 2013		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Money market fund	$	11,748	$	11,748	$	—	$	—
U.S. Treasury notes		2,747		2,747		—		—
Government sponsored enterprise securities		78,560		—		78,560		—
Corporate debt securities		65,282		—		65,282		—
Commercial paper		27,494		—		27,494		—

	$	185,831	$	14,495	$	171,336	$	—


			Fair Value Measurements at Reporting Date Using
	December 31, 2012		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Money market fund	$	51,216	$	51,216	$	—	$	—
U.S. Treasury notes		2,030		2,030		—		—
Government sponsored enterprise securities		54,352		—		54,352		—

	$	107,598	$	53,246	$	54,352	$	—

Balance Sheet Components (Tables)

12 Months Ended

Dec. 31, 2013

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Property and Equipment, Net

Property and equipment, net, consisted of the following:


	Estimated Useful Lives (Years)	December 31,
	Estimated Useful Lives (Years)	2013			2012
		(in thousands)
Machinery and equipment	5–7	$	875		$	2,578
Computers and software	3		863			981
Leasehold improvements	3–10		570			1,057
Furniture and fixtures	3–10		245			159

			2,553			4,775
Accumulated depreciation and amortization			(1,974	)		(4,733	)

		$	579		$	42

Accrued Expenses

Accrued expenses consisted of the following:


	December 31,
	2013		2012
	(in thousands)
Accrued research and development services	$	4,207	$	3,216
Accrued compensation and benefits		1,865		413
Accrued professional fees		308		364
Other		172		146

	$	6,552	$	4,139

Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2013

Equity [Abstract]

Stock Option Transactions

Stock option transactions during the year ended December 31, 2013 are presented below:


	Number of Shares			Weighted- Average Exercise Prices		Weighted Average Remaining Contractual Term
Outstanding at January 1, 2013		6,948,456		$	3.08
Granted		1,954,500		$	16.68
Exercised		(1,455,406	)	$	2.36
Canceled/forfeited		(109,412	)	$	5.04

Outstanding at December 31, 2013		7,338,138		$	6.81		7.1

Vested and expected to vest at December 31, 2013		7,034,407		$	6.53		7.0

Exercisable at December 31, 2013		4,314,480		$	3.79		5.9

Summary of Stock Options Outstanding

The following table summarizes information about stock options outstanding at December 31, 2013:


Options Outstanding					Options Exercisable
Range of Exercise Prices	Number of Shares		Weighted- Average Remaining Contractual Life	Weighted- Average Exercise Price	Number of Shares		Weighted- Average Exercise Price
$0.96–$ 1.56		1,589,996	6.9	$1.42		1,405,676	$1.43
$1.57–$ 1.86		1,273,411	7.3	$1.65		913,487	$1.66
$1.87–$ 2.39		1,443,343	7.3	$2.14		842,284	$2.11
$2.40–$14.89		1,275,608	4.3	$8.09		971,503	$8.45
$14.90–$27.47		1,755,780	9.0	$18.36		181,530	$15.61

		7,338,138		$6.81		4,314,480	$3.79

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2013

Income Tax Disclosure [Abstract]

Components of Deferred Tax Assets

The components of the deferred tax assets are as follows:


	2013			2012
	(in thousands)
NOL carryforwards	$	136,583		$	127,894
R&D credit carryforwards		11,227			11,056
Capitalized R&D		8,003			4,075
Stock-based compensation		3,221			2,906
Other		1,207			775

		160,241			146,706
Valuation allowance		(160,241	)		(146,706	)

	$	—		$	—

Reconciliation of Income Taxes to Amount Computed by Applying Statutory Federal Income Tax Rate to Net Loss

A reconciliation of income taxes to the amount computed by applying the statutory federal income tax rate to the net loss is summarized as follows:


	2013			2012			2011
	(in thousands)
Amounts computed at statutory federal rate	$	(12,902	)	$	(7,088	)	$	(7,734	)
Stock-based compensation and other permanent differences		244			209			306
Reduction of deferred tax assets under Section 382 of the Code		2,781			—			—
R&D credits		(1,269	)		(937	)		(514	)
Change in valuation allowance		13,509			8,375			8,820
State taxes		(2,140	)		(1,171	)		(1,288	)
Foreign taxes		—			(4	)		59
Other		(223	)		616			368

	$	0		$	0		$	17

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2013

Commitments And Contingencies Disclosure [Abstract]

Future Noncancelable Minimum Payment Obligations under Operating Lease Arrangements

Future noncancelable minimum payment obligations under operating lease arrangements were as follows at December 31, 2013:


Year Ending	(in thousands)
2014	$	838
2015		866
2016		583
2017		—
Thereafter		—

	$	2,287

Selected Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2013

Quarterly Financial Information Disclosure [Abstract]

Selected Quarterly Financial Data


2013	March 31,			June 30,			September 30,			December 31,
	(in thousands, except per share data)
Revenues	$	417		$	451		$	240		$	37
Net loss	$	(6,123	)	$	(9,081	)	$	(10,695	)	$	(12,049	)
Net loss per common share, basic and diluted	$	(0.08	)	$	(0.11	)	$	(0.12	)	$	(0.13	)

2012	March 31,			June 30,			September 30,			December 31,
	(in thousands, except per share data)
Revenues	$	450		$	599		$	3,478		$	380
Net loss	$	(6,218	)	$	(5,419	)	$	(2,402	)	$	(6,810	)
Net loss per common share, basic and diluted	$	(0.12	)	$	(0.10	)	$	(0.04	)	$	(0.11	)

Organization and Nature of Operations - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2013	Dec. 31, 2012
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Accumulated deficit	$ (405,668)	$ (367,720)

Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2013 USD ($) Segment	Dec. 31, 2012	Dec. 31, 2011
Summary Of Significant Accounting Policy [Line Items]
Impairment losses \| $	$ 0
Number of business segments \| Segment	1
Revenues \| Allergan, Inc.
Summary Of Significant Accounting Policy [Line Items]
Percentage of revenues from collaborative partners to total revenues	50.00%	23.00%	52.00%
Revenues \| National Institutes of Health
Summary Of Significant Accounting Policy [Line Items]
Percentage of revenues from collaborative partners to total revenues	19.00%
Revenues \| Meiji Seika Pharma Co., Ltd.
Summary Of Significant Accounting Policy [Line Items]
Percentage of revenues from collaborative partners to total revenues		66.00%	25.00%
Revenues \| Michael J. Fox Foundation
Summary Of Significant Accounting Policy [Line Items]
Percentage of revenues from collaborative partners to total revenues	15.00%		13.00%
Minimum
Summary Of Significant Accounting Policy [Line Items]
Property and equipment, estimated useful lives	3 years
Minimum \| Revenues
Summary Of Significant Accounting Policy [Line Items]
Percentage of revenues from collaborative partners to total revenues	10.00%	10.00%	10.00%
Maximum
Summary Of Significant Accounting Policy [Line Items]
Property and equipment, estimated useful lives	10 years

Assumptions Used to Estimate Fair Value of Employee Stock Options (Detail) - Options	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Assumptions used to Determine Fair Value Options [Line Items]
Expected volatility	94.00%		98.00%
Expected volatility, minimum		98.00%
Expected volatility, maximum		99.00%
Risk-free interest rate		1.00%
Risk-free interest rate, minimum	1.00%		1.00%
Risk-free interest rate, maximum	2.00%		2.00%
Expected forfeiture rate	8.00%	9.00%	10.00%
Expected dividend yield	0.00%	0.00%	0.00%
Expected life of options in years	6 years		5 years 9 months 18 days
Minimum
Assumptions used to Determine Fair Value Options [Line Items]
Expected life of options in years		5 years 9 months 18 days
Maximum
Assumptions used to Determine Fair Value Options [Line Items]
Expected life of options in years		6 years

Assumptions Used to Estimate Fair Value Purchase Rights of Each Offering Under Employee Stock Purchase Plan (Detail) - Employee Stock Purchase Plan	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Employee Stock Purchase Plan [Line Items]
Expected volatility, minimum	69.00%	69.00%	64.00%
Expected volatility, maximum	118.00%	137.00%	111.00%
Risk-free interest rate, minimum	0.10%	0.10%	0.10%
Risk-free interest rate, maximum	0.30%	0.30%	0.40%
Expected dividend yield	0.00%	0.00%	0.00%
Expected life of offering in years	10 years
Minimum
Employee Stock Purchase Plan [Line Items]
Expected life of offering in years	6 months	6 months	6 months
Maximum
Employee Stock Purchase Plan [Line Items]
Expected life of offering in years	2 years	2 years	2 years

Potential Common Shares Excluded in Calculating Basic and Diluted Net Loss Per Common Share (Detail) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities to purchase common stock	10,361	11,256	9,973
Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities to purchase common stock	7,245	6,868	5,414
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities to purchase common stock	3,116	4,388	4,559

Investment Securities, Available-for-Sale and Classified as Cash Equivalents (Detail) - USD ($) $ in Thousands	Dec. 31, 2013	Dec. 31, 2012
Schedule of Investments [Line Items]
Amortized Cost	$ 174,038	$ 56,382
Unrealized Gains	59	5
Unrealized (Losses)	(14)	(5)
Estimated Fair Value	174,083	56,382
U.S. Treasury notes
Schedule of Investments [Line Items]
Amortized Cost	2,743	2,029
Unrealized Gains	4	1
Estimated Fair Value	2,747	2,030
Government sponsored enterprise securities
Schedule of Investments [Line Items]
Amortized Cost	78,537	54,353
Unrealized Gains	28	4
Unrealized (Losses)	(5)	(5)
Estimated Fair Value	78,560	$ 54,352
Corporate debt securities
Schedule of Investments [Line Items]
Amortized Cost	65,290
Unrealized Gains	1
Unrealized (Losses)	(9)
Estimated Fair Value	65,282
Commercial paper
Schedule of Investments [Line Items]
Amortized Cost	27,468
Unrealized Gains	26
Estimated Fair Value	$ 27,494

- Definition

Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-12.Column C.3,4)
-URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611133-123010

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-12C.Column C.7)
-URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611225-123010

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 6
-Subparagraph (SX 210.12-14.Column E.2,3)
-URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611322-123010

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 5
-Subparagraph (SX 210.12-13.Column C.6)
-URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611282-123010

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column C
-Article 12

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph 3, 4
-Article 12

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 14
-Paragraph 2, 3
-Article 12

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 13
-Paragraph 6
-Article 12

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12C
-Paragraph 7
-Article 12

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 14
-Paragraph Column E
-Article 12

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 13
-Paragraph Column C
-Article 12

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12C
-Paragraph Column C
-Article 12

+ Details

Investment Securities - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2013	Dec. 31, 2012
Schedule of Investments [Line Items]
Available-for-sale investment securities	$ 174,083	$ 50,068
Maturity dates more than 1 and less than 2 years
Schedule of Investments [Line Items]
Available-for-sale investment securities	$ 33,500	$ 14,200

Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Fair Value Disclosures [Abstract]
Investment, fair value disclosure	$ 185,831	$ 107,598
Impairment of investment securities	$ 0	$ 0

Fair Value Measurements of Cash Equivalents and Available-For-Sale Investment Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	$ 185,831	$ 107,598
Money market fund
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	11,748	51,216
U.S. Treasury notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value disclosure	2,747	2,030
Government sponsored enterprise securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value disclosure	78,560	54,352
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value disclosure	65,282
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value disclosure	27,494
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	14,495	53,246
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Money market fund
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	11,748	51,216
Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. Treasury notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value disclosure	2,747	2,030
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	171,336	54,352
Significant Other Observable Inputs (Level 2) \| Government sponsored enterprise securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value disclosure	78,560	$ 54,352
Significant Other Observable Inputs (Level 2) \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value disclosure	65,282
Significant Other Observable Inputs (Level 2) \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value disclosure	$ 27,494

Property and Equipment, Net (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,553	$ 4,775
Accumulated depreciation and amortization	(1,974)	(4,733)
Property and equipment, net	$ 579	42
Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	3 years
Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	10 years
Machinery and Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 875	2,578
Machinery and Equipment \| Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	5 years
Machinery and Equipment \| Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	7 years
Computer And Software
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	3 years
Property and equipment, gross	$ 863	981
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 570	1,057
Leasehold Improvements \| Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	3 years
Leasehold Improvements \| Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	10 years
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 245	$ 159
Furniture and Fixtures \| Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	3 years
Furniture and Fixtures \| Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	10 years

Balance Sheet Components - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Depreciation and amortization of property and equipment	$ 79	$ 109	$ 285
Removal of fully depreciated property, machinery and equipment	2,800	1,500
Gain on sale of machinery and equipment	$ 10	$ 252

Accrued Expenses (Detail) - USD ($) $ in Thousands	Dec. 31, 2013	Dec. 31, 2012
Payables And Accruals [Abstract]
Accrued research and development services	$ 4,207	$ 3,216
Accrued compensation and benefits	1,865	413
Accrued professional fees	308	364
Other	172	146
Accrued expenses	$ 6,552	$ 4,139

Collaborative Research and Licensing Agreements - Additional Information (Detail)	3 Months Ended								12 Months Ended
	Dec. 31, 2013 USD ($)	Sep. 30, 2013 USD ($)	Jun. 30, 2013 USD ($)	Mar. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Sep. 30, 2012 USD ($)	Jun. 30, 2012 USD ($)	Mar. 31, 2012 USD ($)	Dec. 31, 2013 USD ($) Contract	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement, revenue recognized	$ 37,000	$ 240,000	$ 451,000	$ 417,000	$ 380,000	$ 3,478,000	$ 599,000	$ 450,000	$ 1,145,000	$ 4,907,000	$ 2,067,000
Allergan, Inc.
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of collaboration agreements \| Contract									3
Collaboration agreement, payments received									$ 19,500,000
Collaboration agreement, original research term									3 years
Collaboration agreement, beginning date									2003-03
Collaboration agreement, revenue recognized									$ 571,000.0	1,100,000	1,100,000
Allergan, Inc. \| Glaucoma Collaboration
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement, payments received									9,900,000
Collaboration agreement, estimated development and regulatory milestones	15,000,000								15,000,000
Allergan, Inc. \| Chronic Pain Collaboration
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement, payments received									10,500,000
Collaboration agreement, estimated development and regulatory milestones	$ 10,000,000								10,000,000
Meiji Seika Pharma Co., Ltd.
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement, revenue recognized										$ 3,200,000	$ 505,000.0
Collaboration agreement, license fees									$ 3,000,000

Stockholders' Equity - Additional Information (Detail)			1 Months Ended	12 Months Ended
Stockholders' Equity - Additional Information (Detail)	May 31, 2013 USD ($) shares	Dec. 31, 2012 USD ($) $ / shares $ / Right shares	Jan. 31, 2011 USD ($) $ / shares $ / Right shares	Dec. 31, 2013 USD ($) $ / shares shares	Dec. 31, 2012 USD ($) $ / shares $ / Right shares	Dec. 31, 2011 USD ($) $ / shares shares	Dec. 31, 2010
Stockholders Equity Note [Line Items]
Proceeds from issuance of common stock and warrants, net of issuance costs \| $	$ 107,900,000			$ 111,682,000	$ 98,204,000	$ 14,022,000
Share of common stock issued	9,200,000	19,000,000	12,565,446
Proceed from sale of stock and warrants \| $		$ 80,500,000	$ 13,900,000
Common stock sale price per share \| $ / shares		$ 4.43	$ 1.19375
Warrants issued		500,000			500,000
Warrants issuance price per share \| $ / shares		$ 4.42
Warrant exercise price \| $ / Right		0.01	1.38		0.01
Warrant expiration date		Dec. 17, 2019	Jan. 11, 2018
Issuance of warrant value \| $		$ 2,200,000	$ 3,300,000
Warrant risk free interest rate		1.10%	2.80%
Volatility percentage		105.80%	99.00%
Warrant term		7 years	7 years
Warrants outstanding		500,000			500,000
Description of warrant		Per their terms, the outstanding warrants to purchase 500,000 shares of common stock may not be exercised if the holder's ownership of the Company's common stock would exceed 19.99 percent following such exercise.
Number of common stock per unit sold			1
Number common stock allowed to purchase			0.35
Dividend Yield			0.00%	0.00%
Warrants exercised for purchase of common shares				1,759,162	1,172,774
Shares of common stock issued upon exercise of warrants				1,643,006	874,719
Warrants outstanding to purchase common stock				1,465,968
Redeemable common stock, shares issued		5,347,137		0	5,347,137
Closing market price of Common stock \| $ / shares				$ 24.99
Aggregate intrinsic value of stock options outstanding and exercisable \| $				$ 91,500,000
Aggregate intrinsic value of stock options exercised \| $				20,700,000	$ 650,000	$ 6,000
Cash received from options exercised \| $				$ 3,400,000
Weighted average fair value of options granted \| $ / shares				$ 12.66	$ 1.51	$ 1.25
Unrecognized compensation costs \| $				$ 20,000,000
Weighted average period cost expected to be recognized				2 years 8 months 12 days
Common stock reserved for issuance under stock purchase plan		6,948,456		7,338,138	6,948,456
Number of periods additional number of shares could be added to shares authorized for issuance				10 years
Eligible employees percentage of earnings withheld to purchase shares under purchase plan				15.00%
Issuance of common stock pursuant to employee stock purchase plan				122,853	205,862	189,879
Average price of stock issued under purchase plan \| $ / shares				$ 2.92	$ 0.60	$ 0.57
Issuance of common stock pursuant to employee stock purchase plan \| $				$ 358,000	$ 123,000	$ 109,000
Common stock reserved for issuance upon exercise of warrants				1,965,968
Employee Stock Purchase Plan
Stockholders Equity Note [Line Items]
Exercise price of Options as percentage of fair market value				100.00%
Options expiration term				10 years
Options vesting period				4 years
Common stock reserved for issuance under stock purchase plan				1,375,000
Common stock remained available for issuance pursuant to the Purchase Plan				333,400
Eligible employees percentage of earnings withheld to purchase shares under purchase plan				85.00%
Weighted average fair value of purchase rights granted \| $ / shares				$ 10.96	$ 2.43	$ 0.67
Non Employee Stock [Member]
Stockholders Equity Note [Line Items]
Stock compensation expense related to stock options \| $				$ 584,000
Underwriter
Stockholders Equity Note [Line Items]
Share of common stock issued	1,200,000
Minimum
Stockholders Equity Note [Line Items]
Warrant risk free interest rate				2.00%
Volatility percentage				93.00%
Warrant term				7 years
Minimum \| Employee Stock Purchase Plan
Stockholders Equity Note [Line Items]
Options expiration term				6 months	6 months	6 months
Maximum
Stockholders Equity Note [Line Items]
Warrant risk free interest rate				3.00%
Volatility percentage				95.00%
Warrant term				10 years
Maximum \| Employee Stock Purchase Plan
Stockholders Equity Note [Line Items]
Options expiration term				2 years	2 years	2 years
Stock Options \| Equity Incentive Plan 2010
Stockholders Equity Note [Line Items]
Exercise price of Options as percentage of fair market value							100.00%
Options expiration term							10 years
Options vesting period							4 years
Number of common stock authorized for issuance				14,048,237
Common stock available for grants				6,710,099
Redeemable common stock
Stockholders Equity Note [Line Items]
Rescission of common stock, value \| $					$ 17,700,000
Redeemable common stock, shares issued		5,347,137			5,347,137
At -The-Market Agreement
Stockholders Equity Note [Line Items]
Proceeds from issuance of common stock and warrants, net of issuance costs \| $					$ 17,100,000
Share of common stock issued					5,347,137
Gross proceeds from issuance of common stock \| $					$ 17,700,000

Stock Option Transactions (Detail)	12 Months Ended
Stock Option Transactions (Detail)	Dec. 31, 2013 $ / shares shares
Number of Shares
Option Outstanding, Beginning Balance \| shares	6,948,456
Granted \| shares	1,954,500
Exercised \| shares	(1,455,406)
Canceled/forfeited \| shares	(109,412)
Option Outstanding, Ending Balance \| shares	7,338,138
Vested and expected to vest \| shares	7,034,407
Exercisable \| shares	4,314,480
Weighted Average Exercise Prices
Weighted Average Exercise Prices, Beginning Balance \| $ / shares	$ 3.08
Weighted Average Exercise Prices, granted \| $ / shares	16.68
Weighted Average Exercise Prices, exercised \| $ / shares	2.36
Weighted Average Exercise Prices, Canceled/forfeited \| $ / shares	5.04
Weighted Average Exercise Prices, Ending Balance \| $ / shares	6.81
Weighted Average Exercise Prices, Vested and expected to vest \| $ / shares	6.53
Weighted Average Exercise Prices, Exercisable \| $ / shares	$ 3.79
Weighted average remaining contractual term, outstanding	7 years 1 month 6 days
Weighted average remaining contractual term, Vested and expected to vest	7 years
Weighted average remaining contractual term, Exercisable	5 years 10 months 24 days

Summary of Stock Options Outstanding (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Number of Shares	7,338,138	6,948,456
Options Outstanding, weighted-average exercise price	$ 6.81	$ 3.08
Options exercisable, Number of Shares	4,314,480
Options exercisable, weighted-average exercise price	$ 3.79
Weighted- Average Remaining Contractual Life	7 years 1 month 6 days
$ 0.96-$ 1.32
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 0.96
Range of Exercise Prices, Upper Limit	$ 1.56
Options Outstanding, Number of Shares	1,589,996
Options Outstanding, weighted-average exercise price	$ 1.42
Options exercisable, Number of Shares	1,405,676
Options exercisable, weighted-average exercise price	$ 1.43
Weighted- Average Remaining Contractual Life	6 years 10 months 24 days
$ 1.33-$ 1.60
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 1.57
Range of Exercise Prices, Upper Limit	$ 1.86
Options Outstanding, Number of Shares	1,273,411
Options Outstanding, weighted-average exercise price	$ 1.65
Options exercisable, Number of Shares	913,487
Options exercisable, weighted-average exercise price	$ 1.66
Weighted- Average Remaining Contractual Life	7 years 3 months 18 days
$ 1.61-$ 2.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 1.87
Range of Exercise Prices, Upper Limit	$ 2.39
Options Outstanding, Number of Shares	1,443,343
Options Outstanding, weighted-average exercise price	$ 2.14
Options exercisable, Number of Shares	842,284
Options exercisable, weighted-average exercise price	$ 2.11
Weighted- Average Remaining Contractual Life	7 years 3 months 18 days
$ 2.01-$ 4.65
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 2.40
Range of Exercise Prices, Upper Limit	$ 14.89
Options Outstanding, Number of Shares	1,275,608
Options Outstanding, weighted-average exercise price	$ 8.09
Options exercisable, Number of Shares	971,503
Options exercisable, weighted-average exercise price	$ 8.45
Weighted- Average Remaining Contractual Life	4 years 3 months 18 days
$ 4.66-$ 15.43
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 14.90
Range of Exercise Prices, Upper Limit	$ 27.47
Options Outstanding, Number of Shares	1,755,780
Options Outstanding, weighted-average exercise price	$ 18.36
Options exercisable, Number of Shares	181,530
Options exercisable, weighted-average exercise price	$ 15.61
Weighted- Average Remaining Contractual Life	9 years

Four Zero One (k) Plan - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Compensation And Retirement Disclosure [Abstract]
Maximum contribution by employee, percentage of pretax earnings	60.00%
Percentage of company's matching contribution with respect to each participant's contribution	100.00%
Company matching contributions to maximum employees eligible compensation	5.00%
Deferred compensation arrangement with individual, description	Effective January 1997, the Company established a deferred compensation plan (the “401(k) Plan”) pursuant to Section 401(k) of the Internal Revenue Code of 1986, as amended (the “Code”), whereby substantially all employees are eligible to contribute up to 60 percent of their pretax earnings, not to exceed amounts allowed under the Code. The Company makes discretionary contributions to the 401(k) Plan equal to 100 percent of each employee’s pretax contributions up to 5 percent of his or her eligible compensation, subject to limitations under the Code. The Company’s total contributions to the 401(k) Plan were $240,000, $180,000, and $156,000 for the years ended December 31, 2013, 2012 and 2011, respectively.
Company contributions to 401 (k) plan	$ 240,000	$ 180,000	$ 156,000

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Income Tax [Line Items]
Federal R&D credit carryforwards	$ 8,000,000
Net operating loss carryforwards related to excess tax deductions for stock compensation	16,400,000
Increase in valuation allowance of deferred tax assets	13,500,000
Liabilities for uncertain tax positions	0	$ 0
Federal
Income Tax [Line Items]
Operating loss carryforwards	$ 360,900,000
Remaining net operating loss carryforward, expiration year	2019
Federal \| Expiring in 2018
Income Tax [Line Items]
Operating loss carryforwards	$ 3,600,000
State
Income Tax [Line Items]
Operating loss carryforwards	$ 332,500,000
Remaining net operating loss carryforward, expiration year	2015
Net operating loss carryforwards with no expiration date	$ 4,900,000
State \| Expiring in 2014
Income Tax [Line Items]
Operating loss carryforwards	7,500,000
Expire in 2018
Income Tax [Line Items]
Federal R&D credit carryforwards	119,000
Foreign
Income Tax [Line Items]
Net operating loss carryforwards with no expiration date	$ 4,100,000

Components of Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
NOL carryforwards	$ 136,583	$ 127,894
R&D credit carryforwards	11,227	11,056
Capitalized R&D	8,003	4,075
Stock-based compensation	3,221	2,906
Other	1,207	775
Deferred Tax Assets, Gross	160,241	146,706
Valuation allowance	(160,241)	(146,706)
Deferred Tax Assets, Net

Reconciliation of Income Taxes to Amount Computed by Applying Statutory Federal Income Tax Rate to Net Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Amounts computed at statutory federal rate	$ (12,902)	$ (7,088)	$ (7,734)
Stock-based compensation and other permanent differences	244	209	306
Reduction of deferred tax assets under Section 382 of the Code	2,781
R&D credits	(1,269)	(937)	(514)
Change in valuation allowance	13,509	8,375	8,820
State taxes	(2,140)	(1,171)	(1,288)
Foreign taxes		(4)	59
Other	(223)	616	368
Income Tax Expense (Benefit)	$ 0	$ 0	$ 17

Commitments and Contingencies - Additional Information (Detail) - USD ($)	1 Months Ended		12 Months Ended
	Apr. 30, 2011	Jun. 30, 2005	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Nov. 30, 2006
Supply Commitment [Line Items]
Operating lease, expiration year			2016-12
Rent expense			$ 594,000	$ 663,000	$ 2,100,000
Operating lease term, years		10 years
One time payment of lease related obligation	$ 690,000
Common stock issued for settlement of lease related obligations	782,339
General and administrative expense	$ 1,100,000		12,720,000	$ 6,999,000	$ 7,610,000
Lease termination charges	1,700,000
Reduction in cumulative translation adjustment balance related to liquidation of substantially all assets of Swedish subsidiary	$ 539,000
Potential future milestones payments to agreement with Ipsen Group						$ 10,500,000
Maximum
Supply Commitment [Line Items]
Development services			$ 19,100,000

Future Noncancelable Minimum Payment Obligations under Operating Lease Arrangements (Detail) $ in Thousands	Dec. 31, 2013 USD ($)
Commitments And Contingencies Disclosure [Abstract]
2014	$ 838
2015	866
2016	583
2017
Thereafter
Operating Leases, Future Minimum Payments Due, Total	$ 2,287

Selected Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 37	$ 240	$ 451	$ 417	$ 380	$ 3,478	$ 599	$ 450	$ 1,145	$ 4,907	$ 2,067
Net loss	$ (12,049)	$ (10,695)	$ (9,081)	$ (6,123)	$ (6,810)	$ (2,402)	$ (5,419)	$ (6,218)	$ (37,948)	$ (20,849)	$ (22,765)
Net loss per common share, basic and diluted	$ (0.13)	$ (0.12)	$ (0.11)	$ (0.08)	$ (0.11)	$ (0.04)	$ (0.10)	$ (0.12)	$ (0.44)	$ (0.38)	$ (0.44)

- Definition

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

+ References

+ Details