Gyre Therapeutics (GYRE) 10-K 16 Mar 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2014	Feb. 28, 2015	Jun. 30, 2014
Document Information [Line Items]
Document Type	10-K
Amendment Flag	FALSE
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Trading Symbol	TRGT
Entity Registrant Name	TARGACEPT INC
Entity Central Index Key	1124105
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		33,793,735
Entity Public Float			$101,556,374

Balance_Sheets

Balance Sheets (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$56,430	$54,485
Investments in marketable securities-short term	50,955	37,844
Current receivables	141	278
Prepaid expenses	615	999
Total current assets	108,141	93,606
Investments in marketable securities-long term	3,418	51,448
Property and equipment, net	428	682
Intangible assets		97
Other assets	12	40
Total assets	111,999	145,873
Current liabilities:
Accounts payable	405	1,296
Accrued expenses	2,509	8,830
Current portion of long-term debt		853
Total current liabilities	2,914	10,979
Long-term debt, net of current portion		283
Total liabilities	2,914	11,262
Commitments and contingencies
Stockholders' equity:
Common stock, $0.001 par value, 100,000,000 shares authorized; 34,306,435 and 33,718,179 shares issued at December 31, 2014 and 2013, respectively; 33,793,735 and 33,718,179 shares outstanding at December 31, 2014 and 2013, respectively	34	34
Preferred stock, $0.001 par value, 5,000,000 shares authorized; 0 shares issued and outstanding at December 31, 2014 and 2013
Capital in excess of par value	422,303	415,123
Accumulated other comprehensive income	4	87
Accumulated deficit	-313,256	-280,633
Total stockholders' equity	109,085	134,611
Total liabilities and stockholders' equity	$111,999	$145,873

Balance_Sheets_Parenthetical

Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	34,306,435	33,718,179
Common stock, shares outstanding	33,793,735	33,718,179
Preferred stock, par value	$0.00	$0.00
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0

Statements_of_Comprehensive_In

Statements of Comprehensive Income (Loss) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating revenues:
License fees and milestones from collaborations		$3,536	$57,420
Grant and other revenue	275	93	440
Net operating revenues	275	3,629	57,860
Operating expenses:
Research and development (including stock-based compensation of $1,614, $2,497 and $3,792 in 2014, 2013 and 2012, respectively)	19,499	38,840	49,087
General and administrative (including stock-based compensation of $1,858, $2,719 and $3,956 in 2014, 2013 and 2012, respectively)	10,172	12,005	13,193
Reductions in force (including stock-based compensation of $98 in 2012)	318		3,718
Total operating expenses	29,989	50,845	65,998
Loss from operations	-29,714	-47,216	-8,138
Other income (expense):
Interest income	585	784	1,070
Gain (loss) on sale of property and equipment	13	-213	55
Interest expense	-23	-53	-86
Total other income (expense)	575	518	1,039
Loss before income taxes	-29,139	-46,698	-7,099
Income tax (expense) benefit	-3,484	-7	101
Net loss	-32,623	-46,705	-6,998
Basic and diluted net loss per share	($0.97)	($1.39)	($0.21)
Weighted average common shares outstanding-basic and diluted	33,780,433	33,640,323	33,476,316
Net loss	-32,623	-46,705	-6,998
Unrealized (loss) gain on available-for-sale securities, net	-83	-114	165
Comprehensive loss	($32,706)	($46,819)	($6,833)

Statements_of_Comprehensive_In1

Statements of Comprehensive Income (Loss) (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Research and Development Expense
Stock-based compensation	$1,614	$2,497	$3,792
General and Administrative Expense
Stock-based compensation	1,858	2,719	3,956
Reduction in force
Stock-based compensation			$98

Statements_of_Stockholders_Equ

Statements of Stockholders' Equity (USD $)	Total	Common Stock	Capital in Excess of Par Value	Accumulated Other Comprehensive Income	Accumulated Deficit
In Thousands, except Share data
Beginning balance at Dec. 31, 2011	$174,288	$33	$401,149	$36	($226,930)
Beginning balance (in shares) at Dec. 31, 2011		33,383,403
Issuance of common stock related to exercise of stock options (in shares)		231,678
Issuance of common stock related to exercise of stock options	614	1	613
Stock-based compensation	7,846		7,846
Net change in unrealized holding gain on available-for-sale marketable securities	165			165
Net loss	-6,998				-6,998
Comprehensive loss	-6,833
Ending balance at Dec. 31, 2012	175,915	34	409,608	201	-233,928
Ending balance (in shares) at Dec. 31, 2012		33,615,081
Issuance of common stock related to exercise of stock options (in shares)		103,098
Issuance of common stock related to exercise of stock options	299		299
Stock-based compensation	5,216		5,216
Net change in unrealized holding gain on available-for-sale marketable securities	-114			-114
Net loss	-46,705				-46,705
Comprehensive loss	-46,819
Ending balance at Dec. 31, 2013	134,611	34	415,123	87	-280,633
Ending balance (in shares) at Dec. 31, 2013		33,718,179
Issuance of common stock related to exercise of stock options (in shares)	75,556	75,556
Issuance of common stock related to exercise of stock options	296		296
Stock-based compensation	3,472		3,472
Excess tax benefits from stock-based compensation	3,412		3,412
Net change in unrealized holding gain on available-for-sale marketable securities	-83			-83
Net loss	-32,623				-32,623
Comprehensive loss	-32,706
Ending balance at Dec. 31, 2014	$109,085	$34	$422,303	$4	($313,256)
Ending balance (in shares) at Dec. 31, 2014		33,793,735

Statements_of_Cash_Flows

Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating activities
Net loss	($32,623)	($46,705)	($6,998)
Adjustments to reconcile net loss to net cash used in operating activities:
Recognition of deferred revenue	-148	-3,536	-57,860
Amortization of premium on marketable securities, net	775	908	937
Depreciation and amortization	351	547	2,212
Stock-based compensation expense	3,472	5,216	7,846
Loss (gain) on disposal of property and equipment	-14	213	-55
Income tax expense (benefit) from other comprehensive income	72	7	-101
Changes in operating assets and liabilities:
Current receivable	131	226	-1,162
Other assets	565	527	2,017
Accounts payable, license fees payable and accrued expenses	-7,212	1,985	-11,515
Deferred license fee revenue	148		440
Net cash used in operating activities	-34,483	-40,612	-64,239
Investing activities
Purchase of investments in marketable securities	-7,169	-57,551	-120,972
Proceeds from sale of investments in marketable securities	40,991	69,882	159,538
Purchase of property and equipment	-4	-92	-333
Proceeds from sale of property and equipment	38	1,170	1,589
Net cash provided by investing activities	33,856	13,409	39,822
Financing activities
Excess tax benefits from stock-based compensation	3,412
Principal payments on long-term debt	-1,136	-851	-1,240
Proceeds from issuance of common stock, net	296	299	614
Net cash provided by (used in) financing activities	2,572	-552	-626
Net increase (decrease) in cash and cash equivalents	1,945	-27,755	-25,043
Cash and cash equivalents at beginning of year	54,485	82,240	107,283
Cash and cash equivalents at end of year	$56,430	$54,485	$82,240

The_Company_and_Nature_of_Oper

The Company and Nature of Operations	12 Months Ended
	Dec. 31, 2014
The Company and Nature of Operations	1. The Company and Nature of Operations
	Targacept, Inc., or the Company, is a Delaware corporation formed on March 7, 1997. The Company is a biopharmaceutical company engaged in the development of novel NNR Therapeutics™ to treat patients suffering from serious nervous system and gastrointestinal/genitourinary diseases and disorders. The Company’s NNR Therapeutics selectively target neuronal nicotinic receptors, which it refers to as NNRs. Its facilities are located in Winston-Salem, North Carolina.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies
	Use of Estimates
	The preparation of financial statements in conformity with U.S. generally accepted accounting principles, or GAAP, requires management to make estimates and assumptions that affect the amounts of assets, liabilities, revenues and expenses reported in the financial statements and accompanying notes. Actual results could differ from these estimates.
	Cash and Cash Equivalents
	The Company considers cash equivalents to be those investments which are highly liquid, readily convertible to cash and mature within three months from the date of purchase.
	Investments in Marketable Securities
	Consistent with its investment policy, the Company invests its cash allocated to fund its short-term liquidity requirements with prominent financial institutions in bank depository accounts and institutional money market funds and the Company invests the remainder of its cash in corporate debt securities and municipal bonds rated at least A quality or equivalent, U.S. Treasury notes and bonds, U.S. and state government agency-backed securities and certificates of deposit.
	The Company determines the appropriate classification of marketable securities at the time of purchase and reevaluates its classification as of each balance sheet date. All marketable securities owned during 2014 and 2013 were classified as available-for-sale. The cost of securities sold is based on the specific identification method. Investments in marketable securities are recorded as of each balance sheet date at fair value, with unrealized gains and, to the extent deemed temporary, unrealized losses included in stockholders’ equity. Interest and dividend income on investments in marketable securities, accretion of discounts and amortization of premiums and realized gains and losses are included in interest income in the statement of comprehensive income (loss).
	An investment in marketable securities is considered to be impaired when a decline in fair value below its cost basis is determined to be other than temporary. The Company evaluates whether a decline in fair value of an investment in marketable securities below its cost basis is other than temporary using available evidence. In the event that the cost basis of the investment exceeds its fair value, the Company evaluates, among other factors, the amount and duration of the period that the fair value is less than the cost basis, the financial health of and business outlook for the issuer, including industry and sector performance and operational and financing cash flow factors, overall market conditions and trends, the Company’s intent to sell the investment and whether it is more likely than not the Company would be required to sell the investment before its anticipated recovery. If a decline in fair value is determined to be other than temporary, the Company records an impairment charge in the statement of comprehensive income (loss) and establishes a new cost basis in the investment.
	Receivables
	The Company’s current receivables at December 31, 2014 and 2013 are primarily related to the Company’s sale of equipment as a result of the Company closing its laboratory operations and the Company’s service revenue. During 2014, 2013 and 2012, the Company sold equipment with a net book value of $4,000, $519,000 and $1,534,000, respectively, of which $13,000, $183,000 and $1,046,000 was receivable at December 31, 2014, 2013 and 2012, respectively.
	Long-lived Assets
	Property and equipment consists primarily of laboratory equipment, office furniture and fixtures and leasehold improvements and is recorded at historical cost, net of accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. Equipment is typically depreciated over 3 to 5 years, office furniture and fixtures are typically depreciated over 7 years, and leasehold improvements are typically amortized over the lesser of the asset life or the lease term.
	The Company capitalizes the costs of intellectual property acquired or licensed from external sources as intangible assets if, at the time of acquisition, the intellectual property has reached technological feasibility. Intellectual property acquired or licensed from external sources that has not reached technological feasibility at the time of acquisition or that has no expected future use is charged to research and development expense as incurred. The Company records all other charges related to the filing, prosecution and maintenance of patents to expense as incurred.
	The Company assesses the net realizable value of its long-lived assets and evaluates these assets for impairment whenever events or changes in business circumstances indicate that the carrying amount of an asset may not be recoverable. An impairment charge would be recognized when estimated undiscounted future cash flows expected to result from the use of the asset and its eventual disposition are less than its carrying amount. An impairment charge, if recognized, would be based on the excess of the carrying value of the impaired asset over its estimated fair value.
	Research and Development Expense
	Research and development costs are expensed as incurred and include direct costs incurred to third parties related to research or development of the Company’s product candidates, salaries of, and stock-based compensation for, personnel involved in research and development activities, contractor fees, administrative expenses and allocations of research and development-related overhead costs. Administrative expenses and research and development-related overhead costs included in research and development expense consist of allocations of facility and equipment lease charges, depreciation and amortization of assets, and insurance, legal and supply costs that are directly related to research and development activities. For the year ended December 31, 2014 the Company recorded insurance proceeds of $790,000 related to clinical trial material manufacturing, as a reduction to research and development expense. The Company directly reduces research and development expenses for amounts reimbursed pursuant to the cost-sharing agreements described in Note 12.
	Accrued Expenses
	The Company records accruals based on estimates of the services received, efforts expended and amounts owed pursuant to contracts with clinical trial sites, contract research organizations and other service providers. In the normal course of business, the Company contracts with third parties to perform various clinical trial and other research and development activities in the ongoing development of potential products. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. Payments under these agreements depend on the performance of services or the achievement of specified events, such as the production of drug substance or clinical trial materials, the recruitment of clinical trial subjects, the completion of portions of a non-clinical study or clinical trial or similar conditions. The objective of the Company’s accrual policy is to match the recording of expenses in its financial statements to the actual services received and efforts expended. As such, expense accruals are recognized based on the Company’s estimate of the degree of completion of the event or events specified in a particular contract as giving rise to a payment.
	Credit Risk
	Financial instruments that potentially subject the Company to credit risk consist principally of cash, investments in marketable securities and receivables from collaborations. The Company has established guidelines for investment of its cash that are designed to emphasize safety, liquidity and preservation of capital. The Company places its cash and cash equivalents with prominent financial institutions. At December 31, 2014 and 2013, the Company had deposits in excess of federally insured limits of $52,324,000 and $57,485,000, respectively.
	Revenue Recognition
	The Company uses the revenue recognition guidance established by Financial Accounting Standards Board, or FASB, Accounting Standards Codification, or ASC, Topic 605, Revenue Recognition, or ASC 605. In determining the accounting for collaboration and alliance agreements, the Company follows the provisions of ASC 605, Subtopic 25, Multiple Element Arrangements, or ASC 605-25. ASC 605-25 provides guidance on whether an arrangement that involves multiple revenue-generating activities or deliverables should be divided into separate units of accounting for revenue recognition purposes and, if division is required, how the arrangement consideration should be allocated among the separate units of accounting. If the arrangement constitutes separate units of accounting according to the separation criteria of ASC 605-25, the consideration received is allocated among the separate units of accounting and the applicable revenue recognition criteria must be applied to each unit. If the arrangement constitutes a single unit of accounting, the revenue recognition policy must be determined for the entire arrangement and the consideration received is recognized over the period of inception through the date on which the last deliverable within the single unit of accounting is expected to be delivered. Revisions to the estimated period of recognition are reflected in revenue prospectively.
	Non-refundable upfront fees, which may include, for example, an initial payment upon effectiveness of the contractual relationship, payment representing a common stock purchase premium or payment to secure a right for a future license, are recorded as deferred revenue and recognized into revenue as license fees and milestones from collaborations on a straight-line basis over the estimated period of the Company’s substantive performance obligations. If the Company does not have substantive performance obligations, it recognizes non-refundable upfront fees into revenue through the date the deliverable is satisfied.
	Revenue for non-refundable payments based on the achievement of milestone events under collaboration agreements is recognized in accordance with ASC 605, Subtopic 28, Milestone Method, or ASC 605-28. Milestone events under the Company’s collaboration agreements may include research, development, regulatory, commercialization or sales events. Under ASC 605-28, a milestone payment is recognized as revenue when the applicable event is achieved if the event meets the definition of a milestone and the milestone is determined to be substantive. ASC 605-28 defines a milestone event as an event having all of the following characteristics: (1) there is substantive uncertainty regarding achievement of the milestone event at the inception of the arrangement; (2) the event can only be achieved based, in whole or in part, on either the company’s performance or a specific outcome resulting from the company’s performance; and (3) if achieved, the event would result in additional payment due to the company. The Company also treats events that can only be achieved based, in whole or in part, on either a third party’s performance or a specific outcome resulting from a third party’s performance as milestone events if the criteria of ASC 605-28 are otherwise satisfied. A milestone is considered substantive if it meets all of the following criteria: (A) the payment is commensurate with either the Company’s performance to achieve the milestone or with the enhancement of the value of the delivered item; (B) the payment relates solely to past performance; and (C) the payment is reasonable relative to all of the deliverables and payment terms within the arrangement. If any of these conditions is not met, the milestone payment is deferred and recognized on a straight-line basis over a period determined as discussed above.
	Research and development costs that are reimbursable under collaboration agreements are recorded in accordance with ASC 605, Subtopic 45, Principal Agent Considerations. Amounts reimbursed under a cost sharing arrangement are reflected as a reduction of research and development expense.
	Grant payments received prior to the Company’s performance of work required by the terms of the award are recorded as deferred revenue and recognized as grant revenue as the Company performs the work and incurs qualifying costs. Service revenue is earned and recognized as research or development is performed and related expenses are incurred.
	Income Taxes
	The Company uses the liability method in accounting for income taxes as required by ASC Topic 740, Income Taxes, or ASC 740. Under ASC 740, deferred tax assets and liabilities are recorded for operating loss and tax credit carryforwards and for the future tax consequences attributable to the differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in the results of operations in the period that includes the enactment date. A valuation allowance is recorded to reduce the carrying amounts of deferred tax assets unless it is more likely than not that the assets will be realized. ASC 740 prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. ASC 740 also provides guidance on de-recognition, classification, interest and penalties, accounting in interim periods, disclosures and transition. The Company’s policy is to classify any interest recognized in accordance with ASC 740 as interest expense and to classify any penalties recognized in accordance with ASC 740 as an expense other than income tax expense.
	Net Income or Loss Per Share
	The Company computes net income or loss per share in accordance with ASC Topic 260, Earnings Per Share, or ASC 260. Under the provisions of ASC 260, basic net income or loss per share, or Basic EPS, is computed by dividing net income or loss by the weighted average number of common shares outstanding. Diluted net income or loss per share, or Diluted EPS, is computed by dividing net income or loss by the weighted average number of common shares outstanding plus, in the case of diluted net income per share, dilutive common share equivalents outstanding.
	The calculations of Basic EPS and Diluted EPS are set forth in the table below (in thousands, except share and per share amounts):
		Year Ended December 31,
		2014			2013			2012
	Basic and diluted:
	Net loss	$	(32,623	)	$	(46,705	)	$	(6,998	)
	Weighted average common shares—basic and diluted		33,780,433			33,640,323			33,476,316
	Basic and diluted EPS	$	(0.97	)	$	(1.39	)	$	(0.21	)
	Common share equivalents consist of the incremental common shares that would be outstanding upon the exercise of stock options, calculated using the treasury stock method. For each of the years ended December 31, 2014, 2013 and 2012, the Company excluded all common share equivalents from the calculation of Diluted EPS because the Company had a net loss. As a result, Diluted EPS is identical to Basic EPS for those years. If the Company had been in a net income position for the years ended December 31, 2014, 2013 or 2012, 4,683,263, 4,364,064 and 4,250,964 shares, respectively, subject to outstanding stock options may have been included in the calculation of common share equivalents using the treasury stock method.
	Stock-Based Compensation
	The Company has two stock-based incentive plans, the 2000 Equity Incentive Plan of Targacept, Inc., as amended and restated through March 15, 2006, or the 2000 Plan, and the Targacept, Inc. 2006 Stock Incentive Plan, as amended and restated through March 9, 2011 and further amended on December 7, 2012, March 13, 2013 and April 10, 2013, or the 2006 Plan. The 2000 Plan and the 2006 Plan, or the Plans, are described more fully in Note 9.
	The Company records stock-based compensation under the fair value recognition provisions of ASC Topic 718, Compensation – Stock Compensation, or ASC 718. Under ASC 718, the Company calculates the fair value of each option grant using the Black-Scholes-Merton valuation formula. The fair value of each grant is recorded as expense on a straight-line basis over the option’s vesting period.
	ASC 718 also requires the benefits of tax deductions in excess of recognized compensation expense to be reported as a financing cash flow. This requirement reduces net operating cash flows and increases net financing cash flows for periods after adoption. The Company cannot estimate the future effect of excess tax deductions or shortfalls on cash flows because they depend on, among other things, when employees exercise stock options and the tax deductions available to the Company at those times.
	Prepaid Expenses
	The Company defers and capitalizes non-refundable advance payments for goods or services to be received in the future. The Company then charges the advance payments to expense ratably as the goods are delivered or the services are rendered. The Company may make adjustments to the amount charged to expense each period if expectations change regarding the timing of delivery of goods or rendering of services.
	Fair Value
	The carrying amounts of cash and cash equivalents, investments in marketable securities, receivables, accounts payable and accrued expenses are considered to be representative of their respective fair values due to their short-term natures and, in the case of investments in marketable securities, their market interest rates. Likewise, the carrying amounts of the Company’s long-term debts are considered to be representative of their fair value due to their respective market interest rates.
	The Company follows ASC Topic 820, Fair Value Measurements and Disclosures, or ASC 820, for application to financial assets. ASC 820 defines fair value, provides a consistent framework for measuring fair value under GAAP and requires fair value financial statement disclosures. ASC 820 applies only to the measurement and disclosure of financial assets that are required or permitted to be measured and reported at fair value under other ASC topics (except for standards that relate to share-based payments such as ASC Topic 718, Compensation – Stock Compensation).
	The valuation techniques required by ASC 820 may be based on either observable or unobservable inputs. Observable inputs reflect readily obtainable data from independent sources, and unobservable inputs reflect the Company’s market assumptions. These inputs are classified into the following hierarchy:
	Level 1 Inputs—quoted prices (unadjusted) in active markets for identical assets that the reporting entity has the ability to access at the measurement date;
	Level 2 Inputs—inputs other than quoted prices included within Level 1 that are observable for the asset, either directly or indirectly; and
	Level 3 Inputs—unobservable inputs for the assets.
	The following tables present the Company’s investments in marketable securities (including, if applicable, those classified on the Company’s balance sheet as cash equivalents) that are measured at fair value on a recurring basis as of December 31, 2014 and 2013, respectively:
	December 31, 2014	Quoted			Significant			Significant
		Prices in			Other			Unobservable
		Active			Observable			Inputs
		Markets			Inputs			(Level 3)
		(Level 1)			(Level 2)
		(in thousands)
	U.S. Treasury and U.S. or state government agency-backed securities	$	22,685		$	—		$	—
	Corporate debt securities		—			30,372			—
	Municipal bonds		—			1,075			—
	Accrued interest		241			—			—
	Total cash equivalents and marketable securities	$	22,926		$	31,447		$	—
December 31, 2013	Quoted			Significant			Significant
	Prices in			Other			Unobservable
	Active			Observable			Inputs
	Markets			Inputs			(Level 3)
	(Level 1)			(Level 2)
	(in thousands)
U.S. Treasury and U.S. or state government agency-backed securities	$	37,029		$	—		$	—
Corporate debt securities		—			43,347			—
Municipal bonds		—			3,509			—
Certificates of deposit		5,000			—			—
Accrued interest		407			—			—
Total cash equivalents and marketable securities	$	42,436		$	46,856		$	—
Corporate debt securities and municipal bonds are valued based on various observable inputs such as benchmark yields, reported trades, broker/dealer quotes, benchmark securities and bids.
Accumulated Other Comprehensive Income or Loss
Accumulated other comprehensive income or loss, as presented in stockholders’ equity on the Company’s balance sheet, reflects the cumulative net unrealized gains or losses on available-for-sale securities for all periods. The table below reflects changes in accumulated other comprehensive income for the year ended December 31, 2014, in thousands.
Accumulated other comprehensive income, January 1, 2014	$	87
Unrealized loss on available-for-sale securities, net		(147	)
Net realized gains on available-for sale securities reclassified out of other comprehensive income		(8	)
Income taxes		72
Accumulated other comprehensive income, December 31, 2014	$	4
Recent Accounting Pronouncements
In May 2014, the FASB issued Accounting Standards Update 2014-09, Revenue from Contracts with Customers, or ASU 2014-09. ASU 2014-09 develops a common revenue standard for GAAP and International Financial Reporting Standards and supersedes most current revenue recognition guidance. ASU 2014-09 outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and requires a company to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the Company expects to be entitled in exchange for those goods or services. ASU 2014-09 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2016. The Company is currently evaluating the impact that the implementation of ASU 2014-09 will have on the Company’s financial statements.

Investments_in_Marketable_Secu

Investments in Marketable Securities	12 Months Ended
	Dec. 31, 2014
Investments in Marketable Securities	3. Investments in Marketable Securities
	The following is a reconciliation of amortized cost to fair value of available-for-sale marketable securities (including those classified on the Company’s balance sheet as cash equivalents) held at December 31, 2014 and 2013:
	December 31, 2014	Amortized		Gross		Gross			Fair
		Cost		Unrealized		Unrealized			Value
				Gains		Losses
		(in thousands)
	Security type
	Marketable Securities—Short term
	U.S. Treasury and U.S. or state government agency-backed securities	$	22,677	$	9	$	(1	)	$	22,685
	Corporate debt securities		27,240		19		(4	)		27,255
	Municipal Bonds		780		1		—			781
	Accrued interest		234		—		—			234
	Marketable Securities—Long term
	Corporate debt securities—long term		3,114		4		(1	)		3,117
	Municipal Bonds		295		—		(1	)		294
	Accrued interest		7		—		—			7
	Total available-for-sale marketable securities	$	54,347	$	33	$	(7	)	$	54,373
	December 31, 2013	Amortized		Gross		Gross			Fair
		Cost		Unrealized		Unrealized			Value
				Gains		Losses
		(in thousands)
	Security type
	Marketable Securities—Short term
	U.S. Treasury and U.S. or state government agency-backed securities	$	16,352	$	39	$	—		$	16,391
	Corporate debt securities		14,307		35		—			14,342
	Municipal bonds		1,910		3		—			1,913
	Certificates of deposit		5,000		—		—			5,000
	Accrued interest		198		—		—			198
	Marketable Securities—Long term
	U.S. Treasury and U.S. or state government agency-backed securities		20,628		14		(4	)		20,638
	Corporate debt securities—long term		28,909		101		(5	)		29,005
	Municipal bonds		1,598		4		(6	)		1,596
	Accrued interest		209		—		—			209
	Total available-for-sale marketable securities	$	89,111	$	196	$	(15	)	$	89,292
	As of December 31, 2014, the Company held investments in marketable securities with unrealized gains of $33,000 and unrealized losses of $7,000. As of December 31, 2014, the Company’s investments in marketable securities reach maturity between January 9, 2015 and December 12, 2016, with a weighted average maturity date of approximately June 24, 2015.

Property_and_Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2014
Property and Equipment	4. Property and Equipment
	As of the respective dates shown, property and equipment consisted of the following:
		December 31,
		2014			2013
		(in thousands)
	Equipment	$	62		$	165
	Office furniture and fixtures		2,015			2,373
	Leasehold improvements		22			22
			2,099			2,560
	Less: accumulated depreciation		(1,671	)		(1,878	)
	Property and equipment, net	$	428		$	682
	The Company recorded $254,000, $505,000 and $2,195,000 of depreciation expense for the years ended December 31, 2014, 2013 and 2012, respectively. During the year ended December 31, 2012, the Company closed its laboratory operations and completed two reductions in force (see Note 13). In connection with the reductions in force, the Company sold laboratory equipment and office furniture and fixtures with a book value of $4,000, $519,000 and $1,534,000 for the year ended December 31, 2014, 2013 and 2012, respectively, which resulted in a cumulative gain of $14,000, a cumulative loss of $213,000 and a cumulative gain of $55,000 for the year ended December 31, 2014, 2013 and 2012, respectively.

Intangible_Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2014
Intangible Assets	5. Intangible Assets
	As of the respective dates shown, intangible assets consisted of the following:
		December 31,
		2014			2013
		(in thousands)
	Patents	$	296		$	296
	Less: accumulated amortization		(296	)		(199	)
	Total	$	—		$	97
	Intangible assets consisted of licensed patent rights assigned to the Company by Layton Bioscience, Inc. in 2002, which had an original value to the Company of $296,000. During 2014, as a result of recent clinical trial failures of a compound, the licensed patent rights of which were assigned to Targacept, the Company determined the intangible assets were impaired and recorded an expense for the full remaining carrying value in general and administrative expenses.

Accrued_Expenses

Accrued Expenses	12 Months Ended
	Dec. 31, 2014
Accrued Expenses	6. Accrued Expenses
	As of the respective dates shown, accrued expenses consisted of the following:
		December 31,
		2014		2013
		(in thousands)
	Clinical trial and nonclinical study costs	$	1,891	$	7,578
	Employee compensation		590		1,200
	Other		28		52
	Total	$	2,509	$	8,830

Longterm_Debt

Long-term Debt	12 Months Ended
	Dec. 31, 2014
Long-term Debt	7. Long-term Debt
	In July 2010, the Company entered into a loan agreement with a bank that provides aggregate borrowing capacity of $4,000,000 to be provided in up to three individual term loans on or prior to June 30, 2011 to fund the purchase of equipment, furnishings, software and other fixed assets. The Company borrowed $1,228,000 under the loan agreement in September 2010 and borrowed an additional $2,132,000 in June 2011. The Company’s September 2010 borrowing bears interest at a fixed rate of 3.40% per annum and is repayable in equal monthly installments of $28,000 beginning January 1, 2011 through the maturity date of December 1, 2014. The Company’s June 2011 borrowing bears interest at a fixed rate of 3.471% per annum and is repayable in equal monthly installments of $48,000 beginning July 1, 2011 through the maturity date of June 1, 2015. Pursuant to the loan agreement, the Company granted a first priority security interest in favor of the bank in assets acquired with the proceeds of the loan. The September 2010 borrowing was paid and satisfied in full in November 2014, and the June 2011 borrowing was paid and satisfied in full in December 2014.
	In March 2008, the Company entered into a loan agreement with a bank that provided borrowing capacity of $5,300,000 to fund the purchase of equipment, furnishings, software and other fixed assets and enable the refinancing of an existing loan facility with another lender. The Company borrowed $4,811,000 upon entering into the loan agreement and borrowed the remaining $489,000 in September 2008. The Company’s March 2008 borrowing bore interest at a fixed rate of 5.231% per annum and was repayable in equal monthly installments of $112,000 beginning April 1, 2008 through the maturity date of March 1, 2012. The March 2008 borrowing was paid and satisfied in full on March 1, 2012. The Company used $1,679,000 of the proceeds from the March 2008 borrowing to pay and satisfy in full the principal and interest outstanding on two tranches of the existing loan facility with another lender. The Company’s September 2008 borrowing bore interest at a fixed rate of 6.131% per annum and was repayable in equal monthly installments of $11,000 beginning October 1, 2008 through the maturity date of September 1, 2012. The September 2008 borrowing was paid and satisfied in full in August 2012.
	As of December 31, 2014, the Company had no remaining unpaid balance related to its loan agreements. The Company paid $26,000, $56,000 and $91,000 in interest under notes payable during the years ended December 31, 2014, 2013 and 2012, respectively.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Taxes	8. Income Taxes
	For the year ended December 31, 2012, the Company recognized $101,000 of income tax benefit as a result of the application of intraperiod tax allocation provisions of ASC 740, under which the Company is required to consider all items (including items recorded in other comprehensive income) in determining the amount of tax benefit that should be allocated to net loss. The non-cash income tax benefit was offset in full by income tax expense recorded in other comprehensive income. The Company recorded $72,000 and $7,000 income tax expense for the years ended December 31, 2014 and 2013, respectively, and a corresponding income tax benefit in other comprehensive income for each period, as the available-for-sale securities began to be sold.
	Because the Company has incurred cumulative net operating losses since inception, all tax years remain open to examination by U.S. federal, North Carolina and Massachusetts tax authorities. An examination of the Company’s 2010 federal income tax return was completed in 2014 and resulted in an adjustment that increased taxable income for 2010 by $15,064,000, decreased taxable income for 2011 by $1,076,000, and decreased taxable income for 2012 by $13,988,000. The examination adjustment had no cumulative effect on federal net operating loss carryforwards. The examination adjustment to the Company’s 2010 federal income tax return resulted in the realization of an additional $3,412,000 of excess tax deductions and an offsetting charge to income tax expense for the year ended December 31, 2014. The excess tax deductions were the result of exercises of stock options in periods of net income that gave rise to tax deductions for stock-based compensation in excess of expense recorded for the stock options under GAAP. For the years shown, components of the Company’s income tax expense (benefit) were as follows:
		Year Ended December 31,
		2014			2013			2012
		(in thousands)
	Current:
	Federal	$	3,412		$	—		$	—
	State		—			—			—
	Net current income tax (benefit) expense		3,412			—			—
	Deferred:
	Federal		(13,477	)		(18,076	)		(1,128	)
	State		(1,488	)		1,010			(718	)
	Valuation allowance		15,037			17,073			1,745
	Net deferred income tax expense (benefit)		72			7			(101	)
	Net income tax expense (benefit)	$	3,484		$	7		$	(101	)
	The following is a reconciliation from the federal income tax rate to the Company’s effective tax rate.
		Year Ended December 31,
		2014			2013			2012
	Expected federal income tax benefit/expense at statutory rate		35	%		35	%		35	%
	Increase (decrease) resulting from:
	Research and development credits		2			4			—
	Stock-based compensation		(1	)		(1	)		(15	)
	State income tax expense, net of federal benefit		3			4			2
	Change in state rates		—			(6	)		—
	Change in unrecognized tax benefit reserves		1			—			—
	Change in valuation allowance		(52	)		(37	)		(25	)
	Other		—			—			4
			(12	)%		(1	)%		1	%
	At December 31, 2014, 2013 and 2012, the Company had net operating loss carryforwards for federal income tax purposes of $259,168,000, $233,170,000, and $187,752,000, respectively, and for state income tax purposes of $244,994,000, $219,792,000 and $176,296,000, respectively. At December 31, 2014, 2013 and 2012, the Company had research and development income tax credit carryforwards for federal income tax purposes of $13,468,000, $12,773,000 and $10,762,000, respectively. The Company had research and development income tax credit carryforwards for state income tax purposes of $587,000 at December 31, 2014, 2013 and 2012. The federal net operating loss carryforwards begin to expire in 2024. The state net operating loss carryforwards begin to expire in 2019. The federal and state research and development tax credits begin to expire in 2021.
	Utilization of the net operating loss carryforwards and credits may be subject to a substantial annual limitation due to ownership change limitations provided by Section 382 of the Internal Revenue Code of 1986, as amended, and similar state provisions. A series of stock issuances gave rise to such an ownership change in December 2004. As a result, an annual limitation is imposed on the Company’s use of net operating loss and credit carryforwards attributable to periods before the change.
	Deferred income taxes reflect the net tax effects of temporary differences between the carrying amount of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. The Company’s net deferred tax assets relate principally to its research and development tax credits and net operating loss carryforwards. A valuation allowance has been recognized to offset the deferred tax assets. If and when recognized, the tax benefit for those items will be reflected in the period in which the benefit is recorded as a reduction of income tax expense. However, in the event the Company has excess tax deductions related to the exercise of stock options, the tax benefit will be reflected as an increase to capital in excess of par value. The utilization of the loss carryforwards to reduce future income taxes will depend on the Company’s ability to generate sufficient taxable income prior to the expiration of the net operating loss carryforwards. The valuation allowance increased by $15,026,000 and $17,110,000 for the years ended December 31, 2014 and 2013, respectively.
	As of the respective dates shown, significant components of the Company’s deferred tax assets (liabilities) were as follows:
		December 31,
		2014			2013
		(in thousands)
	Deferred tax assets:
	Net operating loss carryforward	$	94,756		$	81,183
	Research and development tax credit		12,739			12,044
	Stock-based compensation		7,317			6,498
	Patents		1,500			1,641
	Collaboration revenue		—			—
	Other		26			36
	Total gross deferred tax assets		116,338			101,402
	Valuation allowance		(116,237	)		(101,211	)
	Net deferred tax asset		101			191
	Deferred tax liabilities
	Equipment and other		(101	)		(191	)
	Net deferred tax asset	$	—		$	—
	As of December 31, 2014, the Company had cumulative tax deductions from exercises of stock options in excess of expense recorded for the stock options under GAAP. The $3,915,000 benefit of these excess tax deductions had not begun to be realized as of December 31, 2014 because the Company incurred operating losses in the years the respective stock options were exercised and has incurred cumulative net operating losses since inception. Accordingly, the tax benefit will not be recognized as an increase to capital in excess of par value unless and until the excess deductions reduce income taxes payable.
	The Company follows the provisions of ASC 740, which prescribes a threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return and also provides guidance on de-recognition, classification, interest and penalties, accounting in interim periods and disclosures. A reconciliation of beginning and ending unrecognized tax benefits is as follows (in thousands).
	Balance at January 1, 2012	$	1,474
	Additions (decreases) based on tax positions related to current and prior years		—
	Balance at December 31, 2012		1,474
	Additions (decreases) based on tax positions related to current and prior years		2
	Balance at December 31, 2013		1,476
	Additions (decreases) based on tax positions related to current and prior years		(159	)
	Balance at December 31, 2014	$	1,317
	None of the unrecognized tax benefits would, if recognized, affect the effective tax rate because the Company has recorded a valuation allowance to fully offset federal and state deferred tax assets. The Company has no tax positions for which it is reasonably possible that the total amount of unrecognized tax benefits will significantly increase or decrease during 2015. No interest or penalties with respect to unrecognized tax positions are recognized in the statement of comprehensive income (loss) for any of the years ended December 31, 2014, 2013 or 2012.

StockBased_Incentive_Plans

Stock-Based Incentive Plans	12 Months Ended
	Dec. 31, 2014
Stock-Based Incentive Plans	9. Stock-Based Incentive Plans
	The 2000 Plan became effective in August 2000. The 2006 Plan became effective in April 2006 and is the successor equity incentive program to the 2000 Plan. All shares previously reserved under the 2000 Plan and not subject to outstanding awards under the 2000 Plan are now reserved for grant under the 2006 Plan. As of December 31, 2014, the number of shares authorized for issuance under the Plans was 7,033,298, of which 3,149,324 shares remained available for grant.
	Awards may be made with respect to the 2006 Plan, or may have been made with respect to both Plans, to participants under the Plans in the form of incentive and nonqualified stock options, restricted stock (or unvested stock awards), stock appreciation rights, stock awards, and performance awards. As of December 31, 2014, the company has granted stock options and unvested stock awards under the Plans. Eligible participants under the Plans include employees, directors and certain independent contractors, consultants or advisors of the Company or a related corporation. Awards made under the Plans have vesting periods that are determined at the discretion of the administrator and range from 0 to 5 years and most commonly have 10-year contractual terms or, in some cases, shorter terms designed to comply with Section 409A of the Internal Revenue Code. The exercise price of stock options granted under the Plans may not be less than 100% of the fair market value of the common stock on the date of grant, as determined by the administrator.
	In addition to awards made under the Plans, on December 3, 2012, the Company granted a nonqualified option to purchase 400,000 shares of its common stock pursuant to an employment agreement entered into by the Company in connection with the hire of its president and chief executive officer. The option, which was not granted pursuant to a Plan, has similar terms to nonqualified stock options granted under the 2006 Plan.
	Under ASC 718, the Company recognizes the grant date fair value of stock awards issued to employees and non-employee directors over the requisite service periods, which are typically the vesting periods. The Company uses the Black-Scholes-Merton formula to estimate the fair value of its stock options. The volatility assumption used in the Black-Scholes-Merton formula is primarily based on the Company’s implied volatility, the calculated historical volatility of twelve to sixteen benchmark companies in the Company’s industry that have been identified as comparable public entities, the Company’s historical volatility and the implied volatility of the same benchmark companies. The expected term for stock options granted during 2014, 2013 and 2012 is based on historical analysis. The risk-free rate for periods within the contractual life of the option is based on the U.S. Treasury yield curve in effect at the time of grant.
	The following table illustrates the weighted average assumptions for the Black-Scholes-Merton model used in determining the fair value of stock options granted as of the respective dates shown:
		Year ended December 31,
		2014			2013			2012
	Dividend yield		—			—			—
	Risk-free interest rate		1.8	%		1.1	%		1	%
	Volatility		111	%		82	%		69	%
	Expected term		5.63 years			5.73 years			6.16 years
	During 2013 and 2012, the Company partially accelerated the vesting of, and/or extended the permitted period for exercise for, some outstanding stock options held by several employees who departed the Company. These modifications resulted in incremental compensation cost recorded by the Company for the year ended December 31, 2013 and 2012 of $573,000 and $1,397,000, respectively.
	A summary of option activity and changes during the year ended December 31, 2014 appears below.
		Shares			Weighted			Weighted			Aggregate
		Subject to			Average			Average			Intrinsic
		Options			Exercise Price			Remaining			Value
					Per Share			Contractual
								Term
											(in thousands)
	Outstanding at January 1, 2014		4,539,628		$	9.93
	Granted		935,368			4.68
	Forfeited		(1,515,466	)		9.53
	Exercised		(75,556	)		3.93
	Outstanding at December 31, 2014		3,883,974		$	8.93			5.21		$	2
	Vested and exercisable at December 31, 2014		2,838,812		$	10.49			3.98		$	1
	The weighted average grant date fair value of options granted during the years ended December 31, 2014, 2013, and 2012 was $3.85, $3.38 and $2.98, respectively. The total intrinsic value of options exercised during the years ended December 31, 2014, 2013, and 2012 was $60,000, $200,000, and $472,000, respectively. During 2014 and 2013, respectively, 12,171 and 176,102 shares subject to options expired upon reaching the 10-year contractual term, and are included in the “Forfeited” amount in the table above.
	A summary of the status of non-vested stock options outstanding as of December 31, 2014 and changes during the year ended December 31, 2014 appears below.
		Shares			Weighted Average
		Subject to			Grant-Date Fair
		Options			Value Per Share
	Non-vested at January 1, 2014		1,357,654		$	4.04
	Granted		935,368			3.85
	Vested		(721,385	)		4.75
	Forfeited		(526,475	)		3.82
	Non-vested at December 31, 2014		1,045,162		$	3.5
	As of December 31, 2014, there was $3,654,000 of total unrecognized compensation expense related to unvested stock options, before considering forfeitures. That cost is expected to be recorded over a weighted average period of 2.56 years. The total fair value of shares subject to stock options that vested during the years ended December 31, 2014, 2013, and 2012 was $3,427,000, $5,140,000 and $7,836,000, respectively.
	The Company uses the closing price on the date of grant as the fair value of its unvested stock awards. A summary of the status of unvested stock awards as of December 31 and changes during the year ended December 31, 2014 appears below.
		Shares			Weighted Average
		Subject to			Grant-Date Fair
		Options			Value Per Share
	Non-vested at January 1, 2014		—		$	—
	Granted		567,700			2.36
	Vested		—			—
	Forfeited		(55,000	)		2.36
	Non-vested at December 31, 2014		512,700		$	2.36
	As of December 31, 2014, there was $1,111,000 of total unrecognized compensation expense related to unvested stock awards. That cost is expected to be recorded over a weighted average period of 2.00 years. The unvested stock awards are reflected on the Company’s balance sheet as “issued” but not “outstanding” at December 31, 2014; and will become “outstanding” as they vest.
	The Company had 3,883,974 and 4,539,337 shares of common stock reserved for future issuance upon the exercise of outstanding stock options at December 31, 2014 and 2013, respectively.
	On January 21, 2015, the Company granted 111,025 stock options to employees. The stock options will vest over 16 quarters, beginning March 31, 2015.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies	10. Commitments and Contingencies
	Leases
	On December 4, 2012, the Company entered into an agreement with B/E Aerospace, Inc. to sublease approximately 18,282 square feet of office space in Winston-Salem, North Carolina. The term of the sublease began on January 1, 2013 and ends on December 30, 2015. The monthly rent payable by the Company under the sublease is approximately $23,000. The sublease is subject to the terms and conditions of the prime lease covering the subleased space between B/E Aerospace and its landlord, SL Winston-Salem, LLC.
	The Company has entered into various other lease agreements, primarily for storage space and equipment. The Company’s previous office lease expired on December 31, 2012. Rent expense incurred by the Company under the office leases and other operating leases was $541,000, $582,000 and $2,819,000 for the years ended December 31, 2014, 2013 and 2012, respectively.
	The following table illustrates expected future lease payments under all operating leases (in thousands):
	2015	$	356
	2016		25
	2017		12
	2018 and thereafter		—
		$	393
	Employment Arrangements
	The Company has entered into employment agreements with some of its employees. Under the agreements, if the Company terminates the employment other than for just cause or if the employee terminates employment for good reason, in each case as that term is defined in the agreement, the employee is entitled, among other things, to receive severance equal to current base salary for from up to 12 to 18 months following termination, depending on the employee and the circumstances of termination. The employee would also be entitled to continuation of the health and life insurance benefits coverage provided as of the date of termination for the period during which he receives severance.
	Under an employment agreement with a former executive officer and a related separation agreement and release, the Company paid severance equal to the departing executive’s regular base salary as of March 31, 2013 for nine months, a pro rata percentage of the departing executive’s target bonus for 2013, and the departing executive’s health and life insurance benefits coverage provided to him as of March 31, 2013 for nine months. These payments and benefits, which represent an aggregate amount of $306,000, were recorded as general and administrative expense for the year ended December 31, 2013.

Retirement_Savings_Plan

Retirement Savings Plan	12 Months Ended
	Dec. 31, 2014
Retirement Savings Plan	11. Retirement Savings Plan
	The Company has a 401(k) retirement plan in which all of its employees are eligible to participate. The Company contributed $194,000, $275,000 and $454,000 to the plan for the years ended December 31, 2014, 2013 and 2012, respectively. The Company matched employee contributions to the plan, on a per employee basis, up to 4% of each employee’s wages, subject to statutory limits, for each of the years ended December 31, 2014, 2013 and 2012.

Strategic_Alliance_and_Collabo

Strategic Alliance and Collaboration Agreements	12 Months Ended
	Dec. 31, 2014
Strategic Alliance and Collaboration Agreements	12. Strategic Alliance and Collaboration Agreements
	AstraZeneca AB
	In December 2005, the Company entered into a collaborative research and license agreement with AstraZeneca AB, or AstraZeneca, that was initially focused in cognitive disorders. In October 2014, AstraZeneca terminated the agreement in its entirety, effective January 2015. When termination of the agreement became effective, all remaining rights and licenses to compounds granted by the Company under the agreement to AstraZeneca were terminated and reverted to the Company, including the rights and license relating to the Company’s product candidate TC-6683 (also known as AZD1446).
	AstraZeneca paid the Company an initial fee of $10,000,000 under the agreement in February 2006. The initial fee included $5,000,000 for grants of licenses to develop and commercialize the Company’s product candidate TC-1734 (formerly known also as AZD3480), which the Company recognized on a straight-line basis over the estimated development period for TC-1734. In September 2010, the Company and AstraZeneca amended the agreement to enable the Company to conduct a clinical trial of TC-1734 in mild to moderate Alzheimer’s disease and to provide for respective roles and responsibilities and associated financial terms for such a study. Under the 2010 amendment, the Company received from AstraZeneca cumulative payments of $6,000,000 during 2010 and 2011. At that time, the Company began recognizing the portion of the $5,000,000 received for grants of licenses not yet recognized and the payments received under the 2010 amendment into revenue on a straight-line basis over the period of the Company’s substantive performance obligations under the agreement as amended.
	In March 2013, the Company and AstraZeneca amended the agreement to permit AstraZeneca to pursue development and commercialization of compounds it had licensed from the Company in any therapeutic area. Also in March 2013, AstraZeneca exercised its right to terminate TC-1734 from the collaboration. As a result, the Company recognized into revenue during the first quarter of 2013 all of the initial fee and payments received under the 2010 amendment that had not yet been recognized as of the date of AstraZeneca’s action, totaling $3,142,000. The Company recognized an aggregate of $3,536,000 and $2,946,000 of the initial fee and the payments received under the 2010 amendment into revenue during the years ended December 31, 2013 and 2012, respectively.
	Under the agreement, AstraZeneca paid the Company an aggregate of $88,120,000, including the initial fee and payments upon the achievement of milestone events, to maintain option rights and for research services rendered in the completed preclinical research collaboration. This entire amount had been fully recognized into revenue in previous periods.
	Prior Collaboration Agreement
	In December 2009, the Company entered into a collaboration and license agreement with AstraZeneca AB for the global development and commercialization of TC-5214 as a treatment for major depressive disorder. Under the agreement, AstraZeneca made an upfront payment to the Company of $200,000,000. The Company recorded the upfront payment made by AstraZeneca as deferred revenue and began recognizing the payment as revenue on a straight-line basis over the estimated period of the Company’s substantive performance obligations under the agreement, or approximately 33 months after the agreement date. The Company recognized $54,473,000 of the upfront payment as revenue for the year ended December 31, 2012.
	Under the agreement, AstraZeneca was responsible for 80% and the Company was responsible for 20% of the costs of the global development program for TC-5214 in major depressive disorder, except that AstraZeneca was responsible for 100% of development costs that were required only for countries outside the United States and the European Union. In addition, for each of the Company and AstraZeneca, costs that were not contemplated at execution to be part of the program were in some cases excluded from the cost-sharing arrangement.
	The Company’s portion of the costs of the TC-5214 development program was $2,175,000 for the year ended December 31, 2012. AstraZeneca’s allocable portion of the program costs paid by the Company was $127,000 for the year ended December 31, 2012. AstraZeneca’s allocable portion of the program costs paid by the Company is reflected in the Company’s financial statements as a reduction to research and development expense.
	In the first quarter of 2012, the Company and AstraZeneca announced that, based on the totality of the results of the Phase 3 development program for TC-5214, a regulatory submission for TC-5214 as an adjunct therapy for major depressive disorder would not be pursued. Also in the first quarter of 2012, the Company reported that the Company and AstraZeneca determined to discontinue a Phase 2b clinical trial of TC-5214 as a “switch” monotherapy. These determinations resulted in a change in the estimated period of the Company’s substantive performance obligations under the agreement, and the Company revised the revenue recognition period for the upfront payment accordingly. As a result, the entire upfront payment was recognized into revenue by June 30, 2012. In April 2012, the Company received notice of termination of the agreement from AstraZeneca. By the terms of the agreement, the termination became effective in May 2012.

Reductions_In_Force

Reductions In Force	12 Months Ended
	Dec. 31, 2014
Reductions In Force	13. Reductions In Force
	On April 25, 2012, the Company announced a reduction in force as part of a plan to focus its resources on its more advanced programs. The restructuring was completed in the second quarter of 2012. The Company recorded $2,312,000 in severance and other charges related to the reduction in force in the year ended December 31, 2012. Upon the completion of the restructuring, the Company’s workforce was reduced by 65 employees, or approximately 46%.
	On October 8, 2012, the Company announced a further reduction in force and the closing of its laboratory operations. Both of these actions were completed in the fourth quarter of 2012. The Company recorded $1,406,000 in severance and other charges related to the reduction in force in the year ended December 31, 2012. Upon the completion of the restructuring, the Company’s workforce was further reduced by 27 employees, or approximately 38%.
	In the fourth quarter of 2014, the Company completed a reduction in force, which reduced the Company’s workforce by 7 employees, or approximately 26%. The Company recorded $318,000 in severance and other charges related to the reduction in force in the year ended December 31, 2014.

Selected_Quarterly_Financial_D

Selected Quarterly Financial Data (unaudited)	12 Months Ended
	Dec. 31, 2014
Selected Quarterly Financial Data (unaudited)	14. Selected Quarterly Financial Data (unaudited)
			2014 Quarter
			First			Second			Third			Fourth
			(in thousands, except share and per share amounts)
	Net operating revenues		$	87		$	36		$	25		$	127
	Loss from operations			(11,756	)		(8,239	)		(4,988	)		(4,731	)
	Net loss			(14,999	)		(8,136	)		(4,860	)		(4,628	)
	Basic net loss per share(1)		$	(0.44	)	$	(0.24	)	$	(0.14	)	$	(0.14	)
	Weighted average common shares outstanding—basic and diluted(2)			33,746,917			33,786,686			33,793,735			33,793,735
			2013 Quarter
			First			Second			Third			Fourth
			(in thousands, except share and per share amounts)
	Net operating revenues		$	3,536		$	—		$	—		$	93
	Loss from operations			(8,274	)		(12,488	)		(13,146	)		(13,308	)
	Net loss			(8,066	)		(12,371	)		(12,902	)		(13,366	)
	Basic net loss per share(1)		$	(0.24	)	$	(0.37	)	$	(0.38	)	$	(0.40	)
	Weighted average common shares outstanding—basic and diluted(2)			33,616,342			33,626,980			33,644,256			33,673,047
	-1	Per common share amounts for the quarters and full years have been calculated separately. Accordingly, the sum of quarterly amounts may not equal the annual amount because of differences in the weighted average common shares outstanding during each period, principally due to the effect of share issuances by the Company during the year.
	-2	Diluted weighted average common shares outstanding are identical to basic weighted average common shares outstanding and Diluted EPS is identical to Basic EPS for the each quarter of 2014 and 2013 because common share equivalents are excluded from the calculations of diluted weighted average common shares outstanding for those quarters, as their effect is antidilutive.

Subsequent_Event

Subsequent Event	12 Months Ended
	Dec. 31, 2014
Subsequent Event	15. Subsequent Event
	On March 5, 2015 the Company announced entry into a definitive Agreement and Plan of Merger (the “Merger Agreement”) with Catalyst Biosciences, Inc. (“Catalyst”), pursuant to which, among other things, subject to the satisfaction or waiver of the conditions set forth in the Merger Agreement, a wholly-owned subsidiary of the Company’s will be merged with and into Catalyst, with Catalyst continuing as the surviving corporation and a wholly-owned subsidiary of the Company’s (the “Proposed Merger”). Immediately following the effective time of the Proposed Merger, existing Catalyst equity holders are expected to own approximately 65% of the capital stock of the combined company, and existing Targacept equity holders are expected to own approximately 35% of the capital stock of the combined company. Prior to the closing of the Proposed Merger, the Company also expects to distribute to its stockholders a dividend of approximately $37,000,000 in aggregate principal amount of redeemable convertible notes, and approximately $20,000,000 in cash (the “Pre-Closing Dividend”). The notes will be convertible into shares of common stock of the combined company at a conversion price of $1.31 per share, which represents 130% of the negotiated per share value of the Company’s assets following the anticipated Pre-Closing Dividend. If, in the future, the redeemable convertible notes are fully converted into Targacept common stock, the Company’s stockholders would own approximately 49% of the outstanding capital stock of the combined company on a pro forma basis as of the anticipated closing date. Targacept stockholders who are entitled to the Pre-Closing Dividend will also be entitled to any net proceeds received as a result of any disposition of Targacept’s NNR compounds and related assets that occurs within up to two years after the closing of the Proposed Merger, unless those assets are sold or otherwise disposed of prior to the closing of the Proposed Merger.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Use of Estimates	Use of Estimates
	The preparation of financial statements in conformity with U.S. generally accepted accounting principles, or GAAP, requires management to make estimates and assumptions that affect the amounts of assets, liabilities, revenues and expenses reported in the financial statements and accompanying notes. Actual results could differ from these estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents
	The Company considers cash equivalents to be those investments which are highly liquid, readily convertible to cash and mature within three months from the date of purchase.
Investments in Marketable Securities	Investments in Marketable Securities
	Consistent with its investment policy, the Company invests its cash allocated to fund its short-term liquidity requirements with prominent financial institutions in bank depository accounts and institutional money market funds and the Company invests the remainder of its cash in corporate debt securities and municipal bonds rated at least A quality or equivalent, U.S. Treasury notes and bonds, U.S. and state government agency-backed securities and certificates of deposit.
	The Company determines the appropriate classification of marketable securities at the time of purchase and reevaluates its classification as of each balance sheet date. All marketable securities owned during 2014 and 2013 were classified as available-for-sale. The cost of securities sold is based on the specific identification method. Investments in marketable securities are recorded as of each balance sheet date at fair value, with unrealized gains and, to the extent deemed temporary, unrealized losses included in stockholders’ equity. Interest and dividend income on investments in marketable securities, accretion of discounts and amortization of premiums and realized gains and losses are included in interest income in the statement of comprehensive income (loss).
	An investment in marketable securities is considered to be impaired when a decline in fair value below its cost basis is determined to be other than temporary. The Company evaluates whether a decline in fair value of an investment in marketable securities below its cost basis is other than temporary using available evidence. In the event that the cost basis of the investment exceeds its fair value, the Company evaluates, among other factors, the amount and duration of the period that the fair value is less than the cost basis, the financial health of and business outlook for the issuer, including industry and sector performance and operational and financing cash flow factors, overall market conditions and trends, the Company’s intent to sell the investment and whether it is more likely than not the Company would be required to sell the investment before its anticipated recovery. If a decline in fair value is determined to be other than temporary, the Company records an impairment charge in the statement of comprehensive income (loss) and establishes a new cost basis in the investment.
Receivables	Receivables
	The Company’s current receivables at December 31, 2014 and 2013 are primarily related to the Company’s sale of equipment as a result of the Company closing its laboratory operations and the Company’s service revenue. During 2014, 2013 and 2012, the Company sold equipment with a net book value of $4,000, $519,000 and $1,534,000, respectively, of which $13,000, $183,000 and $1,046,000 was receivable at December 31, 2014, 2013 and 2012, respectively.
Long-lived Assets	Long-lived Assets
	Property and equipment consists primarily of laboratory equipment, office furniture and fixtures and leasehold improvements and is recorded at historical cost, net of accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. Equipment is typically depreciated over 3 to 5 years, office furniture and fixtures are typically depreciated over 7 years, and leasehold improvements are typically amortized over the lesser of the asset life or the lease term.
	The Company capitalizes the costs of intellectual property acquired or licensed from external sources as intangible assets if, at the time of acquisition, the intellectual property has reached technological feasibility. Intellectual property acquired or licensed from external sources that has not reached technological feasibility at the time of acquisition or that has no expected future use is charged to research and development expense as incurred. The Company records all other charges related to the filing, prosecution and maintenance of patents to expense as incurred.
	The Company assesses the net realizable value of its long-lived assets and evaluates these assets for impairment whenever events or changes in business circumstances indicate that the carrying amount of an asset may not be recoverable. An impairment charge would be recognized when estimated undiscounted future cash flows expected to result from the use of the asset and its eventual disposition are less than its carrying amount. An impairment charge, if recognized, would be based on the excess of the carrying value of the impaired asset over its estimated fair value.
Research and Development Expense	Research and Development Expense
	Research and development costs are expensed as incurred and include direct costs incurred to third parties related to research or development of the Company’s product candidates, salaries of, and stock-based compensation for, personnel involved in research and development activities, contractor fees, administrative expenses and allocations of research and development-related overhead costs. Administrative expenses and research and development-related overhead costs included in research and development expense consist of allocations of facility and equipment lease charges, depreciation and amortization of assets, and insurance, legal and supply costs that are directly related to research and development activities. For the year ended December 31, 2014 the Company recorded insurance proceeds of $790,000 related to clinical trial material manufacturing, as a reduction to research and development expense. The Company directly reduces research and development expenses for amounts reimbursed pursuant to the cost-sharing agreements described in Note 12.
Accrued Expenses	Accrued Expenses
	The Company records accruals based on estimates of the services received, efforts expended and amounts owed pursuant to contracts with clinical trial sites, contract research organizations and other service providers. In the normal course of business, the Company contracts with third parties to perform various clinical trial and other research and development activities in the ongoing development of potential products. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. Payments under these agreements depend on the performance of services or the achievement of specified events, such as the production of drug substance or clinical trial materials, the recruitment of clinical trial subjects, the completion of portions of a non-clinical study or clinical trial or similar conditions. The objective of the Company’s accrual policy is to match the recording of expenses in its financial statements to the actual services received and efforts expended. As such, expense accruals are recognized based on the Company’s estimate of the degree of completion of the event or events specified in a particular contract as giving rise to a payment.
Credit Risk	Credit Risk
	Financial instruments that potentially subject the Company to credit risk consist principally of cash, investments in marketable securities and receivables from collaborations. The Company has established guidelines for investment of its cash that are designed to emphasize safety, liquidity and preservation of capital. The Company places its cash and cash equivalents with prominent financial institutions. At December 31, 2014 and 2013, the Company had deposits in excess of federally insured limits of $52,324,000 and $57,485,000, respectively.
Revenue Recognition	Revenue Recognition
	The Company uses the revenue recognition guidance established by Financial Accounting Standards Board, or FASB, Accounting Standards Codification, or ASC, Topic 605, Revenue Recognition, or ASC 605. In determining the accounting for collaboration and alliance agreements, the Company follows the provisions of ASC 605, Subtopic 25, Multiple Element Arrangements, or ASC 605-25. ASC 605-25 provides guidance on whether an arrangement that involves multiple revenue-generating activities or deliverables should be divided into separate units of accounting for revenue recognition purposes and, if division is required, how the arrangement consideration should be allocated among the separate units of accounting. If the arrangement constitutes separate units of accounting according to the separation criteria of ASC 605-25, the consideration received is allocated among the separate units of accounting and the applicable revenue recognition criteria must be applied to each unit. If the arrangement constitutes a single unit of accounting, the revenue recognition policy must be determined for the entire arrangement and the consideration received is recognized over the period of inception through the date on which the last deliverable within the single unit of accounting is expected to be delivered. Revisions to the estimated period of recognition are reflected in revenue prospectively.
	Non-refundable upfront fees, which may include, for example, an initial payment upon effectiveness of the contractual relationship, payment representing a common stock purchase premium or payment to secure a right for a future license, are recorded as deferred revenue and recognized into revenue as license fees and milestones from collaborations on a straight-line basis over the estimated period of the Company’s substantive performance obligations. If the Company does not have substantive performance obligations, it recognizes non-refundable upfront fees into revenue through the date the deliverable is satisfied.
	Revenue for non-refundable payments based on the achievement of milestone events under collaboration agreements is recognized in accordance with ASC 605, Subtopic 28, Milestone Method, or ASC 605-28. Milestone events under the Company’s collaboration agreements may include research, development, regulatory, commercialization or sales events. Under ASC 605-28, a milestone payment is recognized as revenue when the applicable event is achieved if the event meets the definition of a milestone and the milestone is determined to be substantive. ASC 605-28 defines a milestone event as an event having all of the following characteristics: (1) there is substantive uncertainty regarding achievement of the milestone event at the inception of the arrangement; (2) the event can only be achieved based, in whole or in part, on either the company’s performance or a specific outcome resulting from the company’s performance; and (3) if achieved, the event would result in additional payment due to the company. The Company also treats events that can only be achieved based, in whole or in part, on either a third party’s performance or a specific outcome resulting from a third party’s performance as milestone events if the criteria of ASC 605-28 are otherwise satisfied. A milestone is considered substantive if it meets all of the following criteria: (A) the payment is commensurate with either the Company’s performance to achieve the milestone or with the enhancement of the value of the delivered item; (B) the payment relates solely to past performance; and (C) the payment is reasonable relative to all of the deliverables and payment terms within the arrangement. If any of these conditions is not met, the milestone payment is deferred and recognized on a straight-line basis over a period determined as discussed above.
	Research and development costs that are reimbursable under collaboration agreements are recorded in accordance with ASC 605, Subtopic 45, Principal Agent Considerations. Amounts reimbursed under a cost sharing arrangement are reflected as a reduction of research and development expense.
	Grant payments received prior to the Company’s performance of work required by the terms of the award are recorded as deferred revenue and recognized as grant revenue as the Company performs the work and incurs qualifying costs. Service revenue is earned and recognized as research or development is performed and related expenses are incurred.
Income Taxes	Income Taxes
	The Company uses the liability method in accounting for income taxes as required by ASC Topic 740, Income Taxes, or ASC 740. Under ASC 740, deferred tax assets and liabilities are recorded for operating loss and tax credit carryforwards and for the future tax consequences attributable to the differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in the results of operations in the period that includes the enactment date. A valuation allowance is recorded to reduce the carrying amounts of deferred tax assets unless it is more likely than not that the assets will be realized. ASC 740 prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. ASC 740 also provides guidance on de-recognition, classification, interest and penalties, accounting in interim periods, disclosures and transition. The Company’s policy is to classify any interest recognized in accordance with ASC 740 as interest expense and to classify any penalties recognized in accordance with ASC 740 as an expense other than income tax expense.
Net Income or Loss Per Share	Net Income or Loss Per Share
	The Company computes net income or loss per share in accordance with ASC Topic 260, Earnings Per Share, or ASC 260. Under the provisions of ASC 260, basic net income or loss per share, or Basic EPS, is computed by dividing net income or loss by the weighted average number of common shares outstanding. Diluted net income or loss per share, or Diluted EPS, is computed by dividing net income or loss by the weighted average number of common shares outstanding plus, in the case of diluted net income per share, dilutive common share equivalents outstanding.
	The calculations of Basic EPS and Diluted EPS are set forth in the table below (in thousands, except share and per share amounts):
		Year Ended December 31,
		2014			2013			2012
	Basic and diluted:
	Net loss	$	(32,623	)	$	(46,705	)	$	(6,998	)
	Weighted average common shares—basic and diluted		33,780,433			33,640,323			33,476,316
	Basic and diluted EPS	$	(0.97	)	$	(1.39	)	$	(0.21	)
	Common share equivalents consist of the incremental common shares that would be outstanding upon the exercise of stock options, calculated using the treasury stock method. For each of the years ended December 31, 2014, 2013 and 2012, the Company excluded all common share equivalents from the calculation of Diluted EPS because the Company had a net loss. As a result, Diluted EPS is identical to Basic EPS for those years. If the Company had been in a net income position for the years ended December 31, 2014, 2013 or 2012, 4,683,263, 4,364,064 and 4,250,964 shares, respectively, subject to outstanding stock options may have been included in the calculation of common share equivalents using the treasury stock method.
Stock-Based Compensation	Stock-Based Compensation
	The Company has two stock-based incentive plans, the 2000 Equity Incentive Plan of Targacept, Inc., as amended and restated through March 15, 2006, or the 2000 Plan, and the Targacept, Inc. 2006 Stock Incentive Plan, as amended and restated through March 9, 2011 and further amended on December 7, 2012, March 13, 2013 and April 10, 2013, or the 2006 Plan. The 2000 Plan and the 2006 Plan, or the Plans, are described more fully in Note 9.
	The Company records stock-based compensation under the fair value recognition provisions of ASC Topic 718, Compensation – Stock Compensation, or ASC 718. Under ASC 718, the Company calculates the fair value of each option grant using the Black-Scholes-Merton valuation formula. The fair value of each grant is recorded as expense on a straight-line basis over the option’s vesting period.
	ASC 718 also requires the benefits of tax deductions in excess of recognized compensation expense to be reported as a financing cash flow. This requirement reduces net operating cash flows and increases net financing cash flows for periods after adoption. The Company cannot estimate the future effect of excess tax deductions or shortfalls on cash flows because they depend on, among other things, when employees exercise stock options and the tax deductions available to the Company at those times.
Prepaid Expenses	Prepaid Expenses
	The Company defers and capitalizes non-refundable advance payments for goods or services to be received in the future. The Company then charges the advance payments to expense ratably as the goods are delivered or the services are rendered. The Company may make adjustments to the amount charged to expense each period if expectations change regarding the timing of delivery of goods or rendering of services.
Fair Value	Fair Value
	The carrying amounts of cash and cash equivalents, investments in marketable securities, receivables, accounts payable and accrued expenses are considered to be representative of their respective fair values due to their short-term natures and, in the case of investments in marketable securities, their market interest rates. Likewise, the carrying amounts of the Company’s long-term debts are considered to be representative of their fair value due to their respective market interest rates.
	The Company follows ASC Topic 820, Fair Value Measurements and Disclosures, or ASC 820, for application to financial assets. ASC 820 defines fair value, provides a consistent framework for measuring fair value under GAAP and requires fair value financial statement disclosures. ASC 820 applies only to the measurement and disclosure of financial assets that are required or permitted to be measured and reported at fair value under other ASC topics (except for standards that relate to share-based payments such as ASC Topic 718, Compensation – Stock Compensation).
	The valuation techniques required by ASC 820 may be based on either observable or unobservable inputs. Observable inputs reflect readily obtainable data from independent sources, and unobservable inputs reflect the Company’s market assumptions. These inputs are classified into the following hierarchy:
	Level 1 Inputs—quoted prices (unadjusted) in active markets for identical assets that the reporting entity has the ability to access at the measurement date;
	Level 2 Inputs—inputs other than quoted prices included within Level 1 that are observable for the asset, either directly or indirectly; and
	Level 3 Inputs—unobservable inputs for the assets.
	The following tables present the Company’s investments in marketable securities (including, if applicable, those classified on the Company’s balance sheet as cash equivalents) that are measured at fair value on a recurring basis as of December 31, 2014 and 2013, respectively:
	December 31, 2014	Quoted			Significant			Significant
		Prices in			Other			Unobservable
		Active			Observable			Inputs
		Markets			Inputs			(Level 3)
		(Level 1)			(Level 2)
		(in thousands)
	U.S. Treasury and U.S. or state government agency-backed securities	$	22,685		$	—		$	—
	Corporate debt securities		—			30,372			—
	Municipal bonds		—			1,075			—
	Accrued interest		241			—			—
	Total cash equivalents and marketable securities	$	22,926		$	31,447		$	—
	December 31, 2013	Quoted			Significant			Significant
		Prices in			Other			Unobservable
		Active			Observable			Inputs
		Markets			Inputs			(Level 3)
		(Level 1)			(Level 2)
		(in thousands)
	U.S. Treasury and U.S. or state government agency-backed securities	$	37,029		$	—		$	—
	Corporate debt securities		—			43,347			—
	Municipal bonds		—			3,509			—
	Certificates of deposit		5,000			—			—
	Accrued interest		407			—			—
	Total cash equivalents and marketable securities	$	42,436		$	46,856		$	—
	Corporate debt securities and municipal bonds are valued based on various observable inputs such as benchmark yields, reported trades, broker/dealer quotes, benchmark securities and bids.
Accumulated Other Comprehensive Income or Loss	Accumulated Other Comprehensive Income or Loss
	Accumulated other comprehensive income or loss, as presented in stockholders’ equity on the Company’s balance sheet, reflects the cumulative net unrealized gains or losses on available-for-sale securities for all periods. The table below reflects changes in accumulated other comprehensive income for the year ended December 31, 2014, in thousands.
	Accumulated other comprehensive income, January 1, 2014	$	87
	Unrealized loss on available-for-sale securities, net		(147	)
	Net realized gains on available-for sale securities reclassified out of other comprehensive income		(8	)
	Income taxes		72
	Accumulated other comprehensive income, December 31, 2014	$	4
Recent Accounting Pronouncements	Recent Accounting Pronouncements
	In May 2014, the FASB issued Accounting Standards Update 2014-09, Revenue from Contracts with Customers, or ASU 2014-09. ASU 2014-09 develops a common revenue standard for GAAP and International Financial Reporting Standards and supersedes most current revenue recognition guidance. ASU 2014-09 outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and requires a company to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the Company expects to be entitled in exchange for those goods or services. ASU 2014-09 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2016. The Company is currently evaluating the impact that the implementation of ASU 2014-09 will have on the Company’s financial statements.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2014
Summary of Calculations of Basic EPS and Diluted EPS	The calculations of Basic EPS and Diluted EPS are set forth in the table below (in thousands, except share and per share amounts):
		Year Ended December 31,
		2014			2013			2012
	Basic and diluted:
	Net loss	$	(32,623	)	$	(46,705	)	$	(6,998	)
	Weighted average common shares—basic and diluted		33,780,433			33,640,323			33,476,316
	Basic and diluted EPS	$	(0.97	)	$	(1.39	)	$	(0.21	)
Investments In Marketable Securities Measured at Fair Value On a Recurring Basis	The following tables present the Company’s investments in marketable securities (including, if applicable, those classified on the Company’s balance sheet as cash equivalents) that are measured at fair value on a recurring basis as of December 31, 2014 and 2013, respectively:
	December 31, 2014	Quoted			Significant			Significant
		Prices in			Other			Unobservable
		Active			Observable			Inputs
		Markets			Inputs			(Level 3)
		(Level 1)			(Level 2)
		(in thousands)
	U.S. Treasury and U.S. or state government agency-backed securities	$	22,685		$	—		$	—
	Corporate debt securities		—			30,372			—
	Municipal bonds		—			1,075			—
	Accrued interest		241			—			—
	Total cash equivalents and marketable securities	$	22,926		$	31,447		$	—
	December 31, 2013	Quoted			Significant			Significant
		Prices in			Other			Unobservable
		Active			Observable			Inputs
		Markets			Inputs			(Level 3)
		(Level 1)			(Level 2)
		(in thousands)
	U.S. Treasury and U.S. or state government agency-backed securities	$	37,029		$	—		$	—
	Corporate debt securities		—			43,347			—
	Municipal bonds		—			3,509			—
	Certificates of deposit		5,000			—			—
	Accrued interest		407			—			—
	Total cash equivalents and marketable securities	$	42,436		$	46,856		$	—
Changes in Accumulated Other Comprehensive Income or Loss	The table below reflects changes in accumulated other comprehensive income for the year ended December 31, 2014, in thousands.
	Accumulated other comprehensive income, January 1, 2014	$	87
	Unrealized loss on available-for-sale securities, net		(147	)
	Net realized gains on available-for sale securities reclassified out of other comprehensive income		(8	)
	Income taxes		72
	Accumulated other comprehensive income, December 31, 2014	$	4

Investments_in_Marketable_Secu1

Investments in Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2014
Reconciliation of Amortized Cost to Fair Value of Available-For-Sale Marketable Securities	The following is a reconciliation of amortized cost to fair value of available-for-sale marketable securities (including those classified on the Company’s balance sheet as cash equivalents) held at December 31, 2014 and 2013:
	December 31, 2014	Amortized		Gross		Gross			Fair
		Cost		Unrealized		Unrealized			Value
				Gains		Losses
		(in thousands)
	Security type
	Marketable Securities—Short term
	U.S. Treasury and U.S. or state government agency-backed securities	$	22,677	$	9	$	(1	)	$	22,685
	Corporate debt securities		27,240		19		(4	)		27,255
	Municipal Bonds		780		1		—			781
	Accrued interest		234		—		—			234
	Marketable Securities—Long term
	Corporate debt securities—long term		3,114		4		(1	)		3,117
	Municipal Bonds		295		—		(1	)		294
	Accrued interest		7		—		—			7
	Total available-for-sale marketable securities	$	54,347	$	33	$	(7	)	$	54,373
	December 31, 2013	Amortized		Gross		Gross			Fair
		Cost		Unrealized		Unrealized			Value
				Gains		Losses
		(in thousands)
	Security type
	Marketable Securities—Short term
	U.S. Treasury and U.S. or state government agency-backed securities	$	16,352	$	39	$	—		$	16,391
	Corporate debt securities		14,307		35		—			14,342
	Municipal bonds		1,910		3		—			1,913
	Certificates of deposit		5,000		—		—			5,000
	Accrued interest		198		—		—			198
	Marketable Securities—Long term
	U.S. Treasury and U.S. or state government agency-backed securities		20,628		14		(4	)		20,638
	Corporate debt securities—long term		28,909		101		(5	)		29,005
	Municipal bonds		1,598		4		(6	)		1,596
	Accrued interest		209		—		—			209
	Total available-for-sale marketable securities	$	89,111	$	196	$	(15	)	$	89,292

Property_and_Equipment_Tables

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2014
Property and Equipment	As of the respective dates shown, property and equipment consisted of the following:
		December 31,
		2014			2013
		(in thousands)
	Equipment	$	62		$	165
	Office furniture and fixtures		2,015			2,373
	Leasehold improvements		22			22
			2,099			2,560
	Less: accumulated depreciation		(1,671	)		(1,878	)
	Property and equipment, net	$	428		$	682

Intangible_Assets_Tables

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Intangible Assets	As of the respective dates shown, intangible assets consisted of the following:
		December 31,
		2014			2013
		(in thousands)
	Patents	$	296		$	296
	Less: accumulated amortization		(296	)		(199	)
	Total	$	—		$	97

Accrued_Expenses_Tables

Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2014
Accrued Expenses	As of the respective dates shown, accrued expenses consisted of the following:
		December 31,
		2014		2013
		(in thousands)
	Clinical trial and nonclinical study costs	$	1,891	$	7,578
	Employee compensation		590		1,200
	Other		28		52
	Total	$	2,509	$	8,830

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Company's Income Tax Expense (Benefit)	For the years shown, components of the Company’s income tax expense (benefit) were as follows:
		Year Ended December 31,
		2014			2013			2012
		(in thousands)
	Current:
	Federal	$	3,412		$	—		$	—
	State		—			—			—
	Net current income tax (benefit) expense		3,412			—			—
	Deferred:
	Federal		(13,477	)		(18,076	)		(1,128	)
	State		(1,488	)		1,010			(718	)
	Valuation allowance		15,037			17,073			1,745
	Net deferred income tax expense (benefit)		72			7			(101	)
	Net income tax expense (benefit)	$	3,484		$	7		$	(101	)
Reconciliation of Federal Income Tax Rate to Company's Effective Tax Rate	The following is a reconciliation from the federal income tax rate to the Company’s effective tax rate.
		Year Ended December 31,
		2014			2013			2012
	Expected federal income tax benefit/expense at statutory rate		35	%		35	%		35	%
	Increase (decrease) resulting from:
	Research and development credits		2			4			—
	Stock-based compensation		(1	)		(1	)		(15	)
	State income tax expense, net of federal benefit		3			4			2
	Change in state rates		—			(6	)		—
	Change in unrecognized tax benefit reserves		1			—			—
	Change in valuation allowance		(52	)		(37	)		(25	)
	Other		—			—			4
			(12	)%		(1	)%		1	%
Components of the Company's Deferred Tax Assets (Liabilities)	As of the respective dates shown, significant components of the Company’s deferred tax assets (liabilities) were as follows:
		December 31,
		2014			2013
		(in thousands)
	Deferred tax assets:
	Net operating loss carryforward	$	94,756		$	81,183
	Research and development tax credit		12,739			12,044
	Stock-based compensation		7,317			6,498
	Patents		1,500			1,641
	Collaboration revenue		—			—
	Other		26			36
	Total gross deferred tax assets		116,338			101,402
	Valuation allowance		(116,237	)		(101,211	)
	Net deferred tax asset		101			191
	Deferred tax liabilities
	Equipment and other		(101	)		(191	)
	Net deferred tax asset	$	—		$	—
Reconciliation of Beginning and Ending Unrecognized Tax Benefits	A reconciliation of beginning and ending unrecognized tax benefits is as follows (in thousands).
	Balance at January 1, 2012	$	1,474
	Additions (decreases) based on tax positions related to current and prior years		—
	Balance at December 31, 2012		1,474
	Additions (decreases) based on tax positions related to current and prior years		2
	Balance at December 31, 2013		1,476
	Additions (decreases) based on tax positions related to current and prior years		(159	)
	Balance at December 31, 2014	$	1,317

StockBased_Incentive_Plans_Tab

Stock-Based Incentive Plans (Tables)	12 Months Ended
	Dec. 31, 2014
Summary of Weighted Average Assumptions of Stock Options Granted	The following table illustrates the weighted average assumptions for the Black-Scholes-Merton model used in determining the fair value of stock options granted as of the respective dates shown:
		Year ended December 31,
		2014			2013			2012
	Dividend yield		—			—			—
	Risk-free interest rate		1.8	%		1.1	%		1	%
	Volatility		111	%		82	%		69	%
	Expected term		5.63 years			5.73 years			6.16 years
Summary of Option Activity	A summary of option activity and changes during the year ended December 31, 2014 appears below.
		Shares			Weighted			Weighted			Aggregate
		Subject to			Average			Average			Intrinsic
		Options			Exercise Price			Remaining			Value
					Per Share			Contractual
								Term
											(in thousands)
	Outstanding at January 1, 2014		4,539,628		$	9.93
	Granted		935,368			4.68
	Forfeited		(1,515,466	)		9.53
	Exercised		(75,556	)		3.93
	Outstanding at December 31, 2014		3,883,974		$	8.93			5.21		$	2
	Vested and exercisable at December 31, 2014		2,838,812		$	10.49			3.98		$	1
Summary of Non-Vested Stock Options	A summary of the status of non-vested stock options outstanding as of December 31, 2014 and changes during the year ended December 31, 2014 appears below.
		Shares			Weighted Average
		Subject to			Grant-Date Fair
		Options			Value Per Share
	Non-vested at January 1, 2014		1,357,654		$	4.04
	Granted		935,368			3.85
	Vested		(721,385	)		4.75
	Forfeited		(526,475	)		3.82
	Non-vested at December 31, 2014		1,045,162		$	3.5
Summary of Unvested Stock Awards	The Company uses the closing price on the date of grant as the fair value of its unvested stock awards. A summary of the status of unvested stock awards as of December 31 and changes during the year ended December 31, 2014 appears below.
		Shares			Weighted Average
		Subject to			Grant-Date Fair
		Options			Value Per Share
	Non-vested at January 1, 2014		—		$	—
	Granted		567,700			2.36
	Vested		—			—
	Forfeited		(55,000	)		2.36
	Non-vested at December 31, 2014		512,700		$	2.36

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2014
Expected Future Lease Payments Under All Operating Leases	The following table illustrates expected future lease payments under all operating leases (in thousands):
	2015	$	356
	2016		25
	2017		12
	2018 and thereafter		—
		$	393

Selected_Quarterly_Financial_D1

Selected Quarterly Financial Data (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Data			2014 Quarter
			First			Second			Third			Fourth
			(in thousands, except share and per share amounts)
	Net operating revenues		$	87		$	36		$	25		$	127
	Loss from operations			(11,756	)		(8,239	)		(4,988	)		(4,731	)
	Net loss			(14,999	)		(8,136	)		(4,860	)		(4,628	)
	Basic net loss per share(1)		$	(0.44	)	$	(0.24	)	$	(0.14	)	$	(0.14	)
	Weighted average common shares outstanding—basic and diluted(2)			33,746,917			33,786,686			33,793,735			33,793,735
			2013 Quarter
			First			Second			Third			Fourth
			(in thousands, except share and per share amounts)
	Net operating revenues		$	3,536		$	—		$	—		$	93
	Loss from operations			(8,274	)		(12,488	)		(13,146	)		(13,308	)
	Net loss			(8,066	)		(12,371	)		(12,902	)		(13,366	)
	Basic net loss per share(1)		$	(0.24	)	$	(0.37	)	$	(0.38	)	$	(0.40	)
	Weighted average common shares outstanding—basic and diluted(2)			33,616,342			33,626,980			33,644,256			33,673,047
	-1	Per common share amounts for the quarters and full years have been calculated separately. Accordingly, the sum of quarterly amounts may not equal the annual amount because of differences in the weighted average common shares outstanding during each period, principally due to the effect of share issuances by the Company during the year.
	-2	Diluted weighted average common shares outstanding are identical to basic weighted average common shares outstanding and Diluted EPS is identical to Basic EPS for the each quarter of 2014 and 2013 because common share equivalents are excluded from the calculations of diluted weighted average common shares outstanding for those quarters, as their effect is antidilutive.

Company_and_Nature_of_Operatio

Company and Nature of Operations - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2014
Organization and Nature of Operations [Line Items]
Corporation formed	7-Mar-97

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	EquityPlan
Significant Accounting Policies [Line Items]
Equipment sold, net book value	$4,000	$519,000	$1,534,000
Deposits in excess of federally insured limits	52,324,000	57,485,000
Shares subject to outstanding stock options	4,683,263	4,364,064	4,250,964
Number of stock-based incentive plans	2
Insurance proceeds related to clinical trial material manufacturing
Significant Accounting Policies [Line Items]
Reduction to research and development expense	790,000
Equipment
Significant Accounting Policies [Line Items]
Equipment sold, net book value	4,000	519,000	1,534,000
Equipment sold, receivable	$13,000	$183,000	$1,046,000
Equipment | Minimum
Significant Accounting Policies [Line Items]
Estimated useful life of long lived assets	3 years
Equipment | Maximum
Significant Accounting Policies [Line Items]
Estimated useful life of long lived assets	5 years
Office furniture and fixtures
Significant Accounting Policies [Line Items]
Estimated useful life of long lived assets	7 years

Summary_of_Calculations_of_Bas

Summary of Calculations of Basic EPS and Diluted EPS (Detail) (USD $)	3 Months Ended																12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Basic and diluted:
Net loss	($4,628)		($4,860)		($8,136)		($14,999)		($13,366)		($12,902)		($12,371)		($8,066)		($32,623)	($46,705)	($6,998)
Weighted average common shares-basic and diluted	33,793,735	[1]	33,793,735	[1]	33,786,686	[1]	33,746,917	[1]	33,673,047	[1]	33,644,256	[1]	33,626,980	[1]	33,616,342	[1]	33,780,433	33,640,323	33,476,316
Basic and diluted EPS																	($0.97)	($1.39)	($0.21)
[1]	Diluted weighted average common shares outstanding are identical to basic weighted average common shares outstanding and Diluted EPS is identical to Basic EPS for the each quarter of 2014 and 2013 because common share equivalents are excluded from the calculations of diluted weighted average common shares outstanding for those quarters, as their effect is antidilutive.

Investments_in_Marketable_Secu2

Investments in Marketable Securities Measured at Fair Value on Recurring Basis (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents and marketable securities	$54,373	$89,292
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents and marketable securities	22,926	42,436
Fair Value, Inputs, Level 1 | US Treasury and Government | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents and marketable securities	22,685	37,029
Fair Value, Inputs, Level 1 | Certificates of Deposit | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents and marketable securities		5,000
Fair Value, Inputs, Level 1 | Accrued Interest | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents and marketable securities	241	407
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents and marketable securities	31,447	46,856
Fair Value, Inputs, Level 2 | Corporate Debt Securities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents and marketable securities	30,372	43,347
Fair Value, Inputs, Level 2 | Municipal Bonds | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents and marketable securities	$1,075	$3,509

Changes_in_Accumulated_Other_C

Changes in Accumulated Other Comprehensive Income Loss (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, January 1, 2014	$87
Unrealized loss on available-for-sale securities, net	-147
Net realized gains on available-for sale securities reclassified out of other comprehensive income	-8
Income taxes	72	7	-101
Accumulated other comprehensive income, December 31, 2014	$4	$87

Investments_in_Marketable_Secu3

Investments in Marketable Securities (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$54,347	$89,111
Gross Unrealized Gains	33	196
Gross Unrealized Losses	-7	-15
Fair Value	54,373	89,292
Marketable Securities - Short term | US Treasury and Government
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	22,677	16,352
Gross Unrealized Gains	9	39
Gross Unrealized Losses	-1
Fair Value	22,685	16,391
Marketable Securities - Short term | Corporate Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	27,240	14,307
Gross Unrealized Gains	19	35
Gross Unrealized Losses	-4
Fair Value	27,255	14,342
Marketable Securities - Short term | Municipal Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	780	1,910
Gross Unrealized Gains	1	3
Fair Value	781	1,913
Marketable Securities - Short term | Certificates of Deposit
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		5,000
Fair Value		5,000
Marketable Securities - Short term | Accrued Interest
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	234	198
Fair Value	234	198
Marketable Securities - Long term | US Treasury and Government
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,114	20,628
Gross Unrealized Gains	4	14
Gross Unrealized Losses	-1	-4
Fair Value	3,117	20,638
Marketable Securities - Long term | Corporate Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		28,909
Gross Unrealized Gains		101
Gross Unrealized Losses		-5
Fair Value		29,005
Marketable Securities - Long term | Municipal Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	295	1,598
Gross Unrealized Gains		4
Gross Unrealized Losses	-1	-6
Fair Value	294	1,596
Marketable Securities - Long term | Accrued Interest
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	7	209
Fair Value	$7	$209

Investments_in_Marketable_Secu4

Investments in Marketable Securities - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Investment [Line Items]
Unrealized gains on marketable securities	$33	$196
Unrealized losses on marketable securities	$7	$15
Maturity date of investments in marketable securities, range start	9-Jan-15
Maturity date of investments in marketable securities, range end	12-Dec-16
Weighted average maturity date	24-Jun-15

Property_and_Equipment_Detail

Property and Equipment (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$2,099	$2,560
Less: accumulated depreciation	-1,671	-1,878
Property and equipment, net	428	682
Equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	62	165
Office Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	2,015	2,373
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$22	$22

Property_and_Equipment_Additio

Property and Equipment - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Depreciation expense	$254,000	$505,000	$2,195,000
Sale of office property and equipment	4,000	519,000	1,534,000
Gain (loss) on sale of property and equipment	$14,000	($213,000)	$55,000

Intangible_Assets_Detail

Intangible Assets (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Finite-Lived Intangible Assets [Line Items]
Patents	$296	$296
Less: accumulated amortization	-296	-199
Total		$97

Intangible_Assets_Additional_I

Intangible Assets - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Finite Lived Intangible Assets Future Amortization Expense [Line Items]
Patents	$296	$296

Accrued_Expenses_Detail

Accrued Expenses (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Accrued Liabilities [Line Items]
Clinical trial and nonclinical study costs	$1,891	$7,578
Employee compensation	590	1,200
Other	28	52
Total	$2,509	$8,830

Longterm_Debt_Additional_Infor

Long-term Debt - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended			1 Months Ended
	Mar. 31, 2008	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2011	Sep. 30, 2010	Sep. 30, 2008	Jul. 31, 2010
Debt Instrument [Line Items]
Repayments of other debt	$1,679,000
Interest paid under notes payable		26,000	56,000	91,000
Loan agreements unpaid balance		0
Loan Agreement
Debt Instrument [Line Items]
Aggregate borrowing capacity	5,300,000							4,000,000
Bank Term Loan
Debt Instrument [Line Items]
Bank loan	4,811,000				2,132,000	1,228,000	489,000
Interest on borrowings	5.23%				3.47%	3.40%	6.13%
Monthly installment	$112,000				$48,000	$28,000	$11,000
Installment start date	1-Apr-08				1-Jul-11	1-Jan-11	1-Oct-08
Installment end date	1-Mar-12				1-Jun-15	1-Dec-14	1-Sep-12

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax [Line Items]
Income tax expense recognized	$72,000	$7,000	($101,000)
Excess tax benefits from stock-based compensation	3,412,000
Research and development carryforwards	12,739,000	12,044,000
Deferred tax assets valuation allowance increase (Decrease)	15,026,000	17,110,000
Cumulative tax deductions for periods of net loss from exercises of stock options	3,915,000
Recognized interest and penalty related to unrecognized tax benefit	0	0	0
Federal Income Tax
Income Tax [Line Items]
Net operating loss carryforwards	259,168,000	233,170,000	187,752,000
Research and development carryforwards	13,468,000	12,773,000	10,762,000
Net operating loss carry forwards expire period	2024
Research and development tax credit carryforward expiration period	2021
State Income Tax Credits
Income Tax [Line Items]
Net operating loss carryforwards	244,994,000	219,792,000	176,296,000
Research and development carryforwards	587,000	587,000	587,000
Net operating loss carry forwards expire period	2019
Research and development tax credit carryforward expiration period	2021
2010
Income Tax [Line Items]
Increase (decrease) in taxable income	15,064,000
2011
Income Tax [Line Items]
Increase (decrease) in taxable income	-1,076,000
2012
Income Tax [Line Items]
Increase (decrease) in taxable income	($13,988,000)

Components_of_Income_Tax_Expen

Components of Income Tax Expense (Benefit) (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current:
Federal	$3,412
State	0	0	0
Net current income tax (benefit) expense	3,412
Deferred:
Federal	-13,477	-18,076	-1,128
State	-1,488	1,010	-718
Valuation allowance	15,037	17,073	1,745
Net deferred income tax expense (benefit)	72	7	-101
Net income tax expense (benefit)	$3,484	$7	($101)

Reconciliation_of_Federal_Inco

Reconciliation of Federal Income Tax Rate to Company's Effective Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Examination [Line Items]
Expected federal income tax benefit/expense at statutory rate	35.00%	35.00%	35.00%
Increase (decrease) resulting from:
Research and development credits	2.00%	4.00%
Stock-based compensation	-1.00%	-1.00%	-15.00%
State income tax expense, net of federal benefit	3.00%	4.00%	2.00%
Change in state rates		-6.00%
Change in unrecognized tax benefit reserves	1.00%
Change in valuation allowance	-52.00%	-37.00%	-25.00%
Other			4.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent, Total	-12.00%	-1.00%	1.00%

Components_of_Companys_Deferre

Components of Company's Deferred Tax Assets (Liabilities) (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Deferred tax assets:
Net operating loss carryforward	$94,756	$81,183
Research and development tax credit	12,739	12,044
Stock-based compensation	7,317	6,498
Patents	1,500	1,641
Collaboration revenue	0	0
Other	26	36
Total gross deferred tax assets	116,338	101,402
Valuation allowance	-116,237	-101,211
Net deferred tax asset	101	191
Deferred tax liabilities
Equipment and other	-101	-191
Net deferred tax asset	$0	$0

Reconciliation_of_Beginning_an

Reconciliation of Beginning and Ending Unrecognized Tax Benefits (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2011
Reconciliation of Unrecognized Tax Benefits [Line Items]
Beginning Balance	$1,476	$1,474	$1,474
Additions (decreases) based on tax positions related to current and prior years	-159	2
Ending Balance	$1,317	$1,476	$1,474

StockBased_Incentive_Plans_Add

Stock-Based Incentive Plans - Additional Information (Detail) (USD $)	12 Months Ended	0 Months Ended	12 Months Ended
	Dec. 31, 2014	Jan. 21, 2015	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value	$3.85
Stock reserved for future issuance	3,883,974		4,539,337
Options granted	935,368
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$1,111,000
Unrecognized compensation cost, recognition period	2 years
Employee Stock Option | Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period		4 years
Options granted		111,025
Stock options vesting period, beginning date		31-Mar-15
Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock shares available to purchase under nonqualified option plan	400,000
Two Thousand And Six Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized for issuance	7,033,298
Common stock available for grant	3,149,324
Contractual term of stock	10 years		10 years
Incremental compensation costs as a result of modifications			573,000	1,397,000
Weighted average grant date fair value	$3.85		$3.38	$2.98
Intrinsic value of options	60,000		200,000	472,000
Options expired	12,171		176,102
Unrecognized compensation expense	3,654,000
Unrecognized compensation cost, recognition period	2 years 6 months 22 days
Fair value of shares vested under 2006 plans	$3,427,000		$5,140,000	$7,836,000
Two Thousand And Six Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period	0 years
Exercise price as a percentage of the fair market value of the common stock	100.00%
Two Thousand And Six Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period	5 years

Summary_of_Weighted_Average_As

Summary of Weighted Average Assumptions of Stock Options Granted (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share based Compensation Arrangement Assumptions Used to Estimate Fair Values of Share Options Granted [Line Items]
Dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate	1.80%	1.10%	1.00%
Volatility	111.00%	82.00%	69.00%
Expected term	5 years 7 months 17 days	5 years 8 months 23 days	6 years 1 month 28 days

Summary_of_Option_Activity_Det

Summary of Option Activity (Detail) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014
Shares
Shares, Beginning Balance	4,539,628
Granted	935,368
Forfeited	-1,515,466
Exercised	-75,556
Shares, Ending Balance	3,883,974
Vested and exercisable at December 31, 2014	2,838,812
Weighted Average Exercise Price Per Share
Weighted Average Exercise Price Per Share, Beginning Balance	$9.93
Granted	$4.68
Forfeited	$9.53
Exercised	$3.93
Weighted Average Exercise Price Per Share, Ending Balance	$8.93
Vested and exercisable at December 31, 2014	$10.49
Outstanding at December 31, 2014	5 years 2 months 16 days
Vested and exercisable at December 31, 2014	3 years 11 months 23 days
Outstanding at December 31, 2014	$2
Vested and exercisable at December 31, 2014	$1

Summary_of_Nonvested_Stock_Opt

Summary of Nonvested Stock Options (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested at January 1, 2014	1,357,654
Granted	935,368
Vested	-721,385
Forfeited	-526,475
Non-vested at December 31, 2014	1,045,162
Weighted Average Grant-Date Fair Value Per Share
Non-vested at January 1, 2014	$4.04
Granted	$3.85
Vested	$4.75
Forfeited	$3.82
Non-vested at December 31, 2014	$3.50

Summary_of_Unvested_Stock_Awar

Summary of Unvested Stock Awards (Detail) (Restricted Stock, USD $)	12 Months Ended
	Dec. 31, 2014
Restricted Stock
Shares Subject to Options
Granted	567,700
Vested	0
Forfeited	-55,000
Non-vested at December 31, 2014	512,700
Weighted Average Grant-Date Fair Value Per Share
Granted	$2.36
Vested	$0
Forfeited	$2.36
Non-vested at December 31, 2014	$2.36

Commitments_and_Contingencies_1

Commitments and Contingencies - Additional Information (Detail) (USD $)	0 Months Ended			3 Months Ended	12 Months Ended
	Dec. 04, 2012	Oct. 08, 2012	Apr. 25, 2012	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	sqft
Loss Contingencies [Line Items]
Subleased office area	18,282
Sublease agreement entry date	1-Jan-13
Sublease agreement end date	30-Dec-15
Monthly rent payable on sublease	$23,000
Operating lease rent expense					541,000	582,000	2,819,000
Severance cost included in general and administrative expenses		1,406,000	2,312,000	318,000	318,000		3,718,000
Employee Severance
Loss Contingencies [Line Items]
Severance cost included in general and administrative expenses						$306,000
Minimum
Loss Contingencies [Line Items]
Severance period for executive officers					12 months
Maximum
Loss Contingencies [Line Items]
Severance period for executive officers					18 months

Expected_Future_Lease_Payments

Expected Future Lease Payments Under Operating Leases (Detail) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Loss Contingencies [Line Items]
2015	$356
2016	25
2017	12
2018 and thereafter	0
Operating Leases, Future Minimum Payments Due, Total	$393

Retirement_Savings_Plan_Additi

Retirement Savings Plan - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Employer contribution under 401(k) retirement plan	$194,000	$275,000	$454,000
Maximum percentage of employee gross pay that the employer may contribute	4.00%	4.00%	4.00%

Strategic_Alliance_and_Collabo1

Strategic Alliance and Collaboration Agreements - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended		107 Months Ended	24 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2009	Feb. 28, 2006	Dec. 31, 2014	Dec. 31, 2011
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Initial program cost for research and development	$19,499,000	$38,840,000	$49,087,000
TC - 5214
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Amount received for research and development process				200,000,000
Deferred revenue recognition period				33 months
Initial program cost for research and development			2,175,000
Allocable portion of the program costs			127,000
AstraZeneca
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Amount received for research and development process					10,000,000
Allocation of initial fee to research collaboration					5,000,000
Initial fee not yet recognized					5,000,000
Aggregate amount received for research and development process						88,120,000
AstraZeneca | Clinical Trial TC-1734
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Amount received for research and development process							6,000,000
Recognized of initial fee as revenue and payments received under amendment		3,536,000	2,946,000
AstraZeneca | Accelerated Portion
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Recognized of initial fee as revenue and payments received under amendment		3,142,000
AstraZeneca | TC - 5214
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Recognized of initial fee as revenue and payments received under amendment			$54,473,000
Percentage cost of the program attributable to respective party US and Europe	80.00%					80.00%
Percentage of development costs, responsible party Rest of World	100.00%
Parent Company | TC - 5214
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Percentage cost of the program attributable to respective party US and Europe	20.00%					20.00%

Reduction_In_Force_Additional_

Reduction In Force - Additional Information (Detail) (USD $)	0 Months Ended		3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Oct. 08, 2012	Apr. 25, 2012	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2012
	Employee	Employee	Employee
Special Charges [Line Items]
Severance and other charges related to the reduction in force	$1,406	$2,312	$318	$318	$3,718
Number of positions eliminated	27	65	7
Percentage of workforce reduced	38.00%	46.00%	26.00%

Quarterly_Financial_Data_Detai

Quarterly Financial Data (Detail) (USD $)	3 Months Ended																12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Data [Line Items]
Net operating revenues	$127		$25		$36		$87		$93						$3,536		$275	$3,629	$57,860
Loss from operations	-4,731		-4,988		-8,239		-11,756		-13,308		-13,146		-12,488		-8,274		-29,714	-47,216	-8,138
Net loss	($4,628)		($4,860)		($8,136)		($14,999)		($13,366)		($12,902)		($12,371)		($8,066)		($32,623)	($46,705)	($6,998)
Basic net loss per share	($0.14)	[1]	($0.14)	[1]	($0.24)	[1]	($0.44)	[1]	($0.40)	[1]	($0.38)	[1]	($0.37)	[1]	($0.24)	[1]
Weighted average common shares outstanding-basic and diluted	33,793,735	[2]	33,793,735	[2]	33,786,686	[2]	33,746,917	[2]	33,673,047	[2]	33,644,256	[2]	33,626,980	[2]	33,616,342	[2]	33,780,433	33,640,323	33,476,316
[1]	Per common share amounts for the quarters and full years have been calculated separately. Accordingly, the sum of quarterly amounts may not equal the annual amount because of differences in the weighted average common shares outstanding during each period, principally due to the effect of share issuances by the Company during the year.
[2]	Diluted weighted average common shares outstanding are identical to basic weighted average common shares outstanding and Diluted EPS is identical to Basic EPS for the each quarter of 2014 and 2013 because common share equivalents are excluded from the calculations of diluted weighted average common shares outstanding for those quarters, as their effect is antidilutive.

Subsequent_Event_Additional_In

Subsequent Event - Additional Information (Detail) (Subsequent Event, Definitive Agreement and Plan of Merger with Catalyst Biosciences, Inc., USD $)	0 Months Ended
In Millions, except Per Share data, unless otherwise specified	Mar. 05, 2015	Mar. 05, 2015
Subsequent Event | Definitive Agreement and Plan of Merger with Catalyst Biosciences, Inc.
Subsequent Event [Line Items]
Expected ownership percentage, acquiree	65.00%	65.00%
Expected ownership percentage, acquirer	35.00%	35.00%
Dividends expected to distribute	$37	$37
Note conversion price	$1.31	$1.31
Percentage at which notes will be converted into shares	130.00%	130.00%
Pre-closing dividend	$20
Ownership percentage on outstanding capital stock of the combined company	49.00%