Fresh Tracks Therapeutics (FRTX) 10-Q 7 Nov 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2013	Oct. 31, 2013
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-13	'
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'
Trading Symbol	'VICL	'
Entity Registrant Name	'VICAL INC	'
Entity Central Index Key	'0000819050	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	86,777,356

Balance_Sheets

Balance Sheets (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$38,811	$43,159
Marketable securities, available-for-sale	17,036	37,639
Restricted cash	3,119	3,059
Receivables and other assets	1,829	2,152
Total current assets	60,795	86,009
Long-term investments	2,039	2,225
Property and equipment, net	4,353	5,284
Intangible assets, net	2,115	2,813
Other assets	192	191
Total assets	69,494	96,522
Current liabilities:	'	'
Accounts payable and accrued expenses	5,173	5,629
Deferred revenue	37	150
Total current liabilities	5,210	5,779
Long-term liabilities:	'	'
Deferred rent	1,391	1,657
Commitments and contingencies	'	'
Stockholders' equity:	'	'
Preferred stock, $0.01 par value, 5,000 shares authorized, none issued and outstanding	'	'
Common stock, $0.01 par value, 160,000 shares authorized, 86,760 and 86,136 shares issued and outstanding at September 30, 2013, and December 31, 2012, respectively	868	861
Additional paid-in capital	438,939	435,915
Accumulated deficit	-376,983	-347,937
Accumulated other comprehensive income	69	247
Total stockholders' equity	62,893	89,086
Total liabilities and stockholders' equity	$69,494	$96,522

Balance_Sheets_Parenthetical

Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, except Per Share data, unless otherwise specified
Statement Of Financial Position [Abstract]	'	'
Preferred stock, par value	$0.01	$0.01
Preferred stock, shares authorized	5,000	5,000
Preferred stock, shares issued	'	'
Preferred stock, shares outstanding	'	'
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	160,000	160,000
Common stock, shares issued	86,760	86,136
Common stock, shares outstanding	86,760	86,136

Statements_of_Operations

Statements of Operations (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenues:	'	'	'	'
Contract and grant revenue	$1,311	$1,682	$3,617	$4,267
License and royalty revenue	232	493	956	10,933
Total revenues	1,543	2,175	4,573	15,200
Operating expenses:	'	'	'	'
Research and development	4,500	3,682	12,080	13,901
Manufacturing and production	3,900	3,853	11,504	9,258
General and administrative	3,123	2,420	10,119	7,898
Total operating expenses	11,523	9,955	33,703	31,057
Loss from operations	-9,980	-7,780	-29,130	-15,857
Other income (expense):	'	'	'	'
Investment and other income, net	97	54	84	507
Net loss	($9,883)	($7,726)	($29,046)	($15,350)
Basic and diluted net loss per share	($0.11)	($0.09)	($0.33)	($0.18)
Weighted average shares used in computing basic and diluted net loss per share	86,998	86,408	86,755	85,762

Statements_of_Comprehensive_Lo

Statements of Comprehensive Loss (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Amounts Reclassified Out Of Accumulated Other Comprehensive Income Loss [Abstract]	'	'	'	'
Net loss	($9,883)	($7,726)	($29,046)	($15,350)
Unrealized (losses) gains on available-for-sale and long-term marketable securities:	'	'	'	'
Unrealized (losses) gains arising during holding period	-65	40	-178	275
Less: Reversal of unrealized losses in accumulated other comprehensive loss upon the sale of long-term marketable securities included in investment and other income	'	'	'	-590
Other comprehensive (loss) gain	-65	40	-178	-315
Total comprehensive loss	($9,948)	($7,686)	($29,224)	($15,665)

Statements_of_Cash_Flows

Statements of Cash Flows (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Cash flows from operating activities:	'	'
Net loss	($29,046)	($15,350)
Adjustments to reconcile net loss to net cash used in operating activities:	'	'
Depreciation and amortization	1,731	1,691
Write-off of abandoned patents and licensed technology	778	71
Gain on sale of property and equipment	'	-9
Compensation expense related to stock options and awards	2,686	2,578
Changes in operating assets and liabilities:	'	'
Receivables and other assets	323	593
Accounts payable and accrued expenses	-502	-816
Deferred revenue	-113	-99
Deferred rent	-220	-176
Net cash used in operating activities	-24,363	-11,517
Cash flows from investing activities:	'	'
Proceeds from the sale of marketable securities	'	3,750
Maturities of marketable securities	25,489	13,741
Purchases of marketable securities	-5,137	-39,412
Purchases of property and equipment	-307	-529
Proceeds from the sale of property and equipment	1	9
Patent expenditures	-376	-318
Net cash provided by (used in) investing activities	19,670	-22,759
Cash flows from financing activities:	'	'
Net proceeds from issuance of common stock	815	48,931
Payment of withholding taxes for net settlement of restricted stock units	-470	-201
Net cash provided by financing activities	345	48,730
Net (decrease) increase in cash and cash equivalents	-4,348	14,454
Cash and cash equivalents at beginning of period	43,159	38,696
Cash and cash equivalents at end of period	$38,811	$53,150

General

General	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]	'
General	'
	1.       GENERAL
	Vical Incorporated, or the Company, a Delaware corporation, was incorporated in April 1987 and has devoted substantially all of its resources since that time to its research and development programs. The Company researches and develops biopharmaceutical products based on its patented DNA delivery technologies for the prevention and treatment of serious or life-threatening diseases.
	All of the Company’s potential products are in research and development phases. No revenues have been generated from the sale of any such products, nor are any such revenues expected for at least the next several years. The Company earns revenue from research and development agreements with pharmaceutical collaborators and grant and contract arrangements with government entities. Most of the Company’s product candidates will require significant additional research and development efforts, including extensive preclinical and clinical testing. All product candidates that advance to clinical testing will require regulatory approval prior to commercial use, and will require significant costs for commercialization. There can be no assurance that the Company’s research and development efforts, or those of its collaborators, will be successful. The Company expects to continue to incur substantial losses and not generate positive cash flows from operations for at least the next several years. No assurance can be given that the Company can generate sufficient product revenue to become profitable or generate positive cash flows from operations.
	The unaudited financial statements at September 30, 2013, and for the three and nine months ended September 30, 2013 and 2012, have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission, or SEC, and with accounting principles generally accepted in the United States applicable to interim financial statements. These unaudited financial statements have been prepared on the same basis as the audited financial statements and include all adjustments, consisting of only normal recurring accruals, which in the opinion of management are necessary to present fairly the Company’s financial position as of the interim date and results of operations for the interim periods presented. Interim results are not necessarily indicative of results for a full year or future periods. The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from those estimates. These unaudited financial statements should be read in conjunction with the Company’s audited financial statements for the year ended December 31, 2012, included in its Annual Report on Form 10-K filed with the SEC.
	The accompanying cash flow statement for the nine months ended September 30, 2012 contains a reclassification of certain amortization expenses from investment activities to operating activities to conform to the current year presentation.
	Cash, Cash Equivalents and Marketable Securities
	Cash and cash equivalents consist of cash and highly liquid securities with original maturities at the date of acquisition of ninety days or less. Investments with an original maturity of more than ninety days are considered marketable securities and have been classified by management as available-for-sale. These investments are classified as current assets, even though the stated maturity date may be one year or more beyond the current balance sheet date which reflects management’s intention to use the proceeds from sales of these securities to fund its operations, as necessary. Such investments are carried at fair value, with unrealized gains and losses included as a separate component of stockholders’ equity. Realized gains and losses from the sale of available-for-sale securities or the amounts, net of tax, reclassified out of accumulated other comprehensive income, if any, are determined on a specific identification basis.
	Restricted Cash
	The Company is required to maintain a letter of credit securing an amount equal to twelve months of the current monthly installment of base rent for the term of its primary facilities lease, which ends in August 2017. Under certain circumstances, the Company may be able to eliminate the need for the letter of credit. As of September 30, 2013, and December 31, 2012, restricted cash of $3.1 million was pledged as collateral for this letter of credit.
	Revenue Recognition
	Revenue is recognized when the four basic criteria of revenue recognition are met: (1) persuasive evidence of an arrangement exists; (2) delivery has occurred or services rendered; (3) the fee is fixed or determinable; and (4) collectability is reasonably assured. Certain of the Company’s revenue is generated through manufacturing contracts and stand-alone license agreements.
	The Company has entered into multiple-element arrangements. In order to account for the multiple-element arrangements, the Company identifies the deliverables included within the agreement and evaluates which deliverables represent separate units of accounting. Analyzing the arrangement to identify deliverables requires the use of judgment, and each deliverable may be an obligation to deliver services, a right or license to use an asset, or another performance obligation.
	The delivered item(s) must have value to the customer on a standalone basis and, if the arrangement includes a general right of return relative to the delivered item, delivery or performance of the undelivered item(s) is considered probable and substantially in the Company’s control.
	A delivered item is considered a separate unit of accounting when the delivered item has value to the partner on a standalone basis based on the consideration of the relevant facts and circumstances for each arrangement. Factors considered in this determination include the research capabilities of the partner and the availability of research expertise in this field in the general marketplace. Arrangement consideration is allocated at the inception of the agreement to all identified units of accounting based on their relative selling price. The relative selling price for each deliverable is determined using vendor specific objective evidence, or VSOE, of selling price or third-party evidence of selling price if VSOE does not exist. If neither VSOE nor third-party evidence of selling price exists, the Company uses its best estimate of the selling price for the deliverable. The amount of allocable arrangement consideration is limited to amounts that are fixed or determinable. The consideration received is allocated among the separate units of accounting, and the applicable revenue recognition criteria are applied to each of the separate units. Changes in the allocation of the sales price between delivered and undelivered elements can impact revenue recognition but do not change the total revenue recognized under any agreement. If facts and circumstances dictate that the license has standalone value from the undelivered items, which generally include research and development services and the manufacture of drug products, the license is identified as a separate unit of accounting and the amounts allocated to the license are recognized upon the delivery of the license, assuming the other revenue recognition criteria have been met. However, if the amounts allocated to the license through the relative selling price allocation exceed the upfront license fee, the amount recognized upon the delivery of the license is limited to the upfront fee received. If facts and circumstances dictate that the license does not have standalone value, the transaction price, including any upfront license fee payments received, are allocated to the identified separate units of accounting and recognized as those items are delivered.
	The terms of the Company’s partnership agreements provide for milestone payments upon achievement of certain regulatory and commercial events. The Company recognizes consideration that is contingent upon the achievement of a milestone in its entirety as revenue in the period in which the milestone is achieved only if the milestone is substantive in its entirety. A milestone is considered substantive when it meets all of the following three criteria: (1) the consideration is commensurate with either the entity’s performance to achieve the milestone or the enhancement of the value of the delivered item(s) as a result of a specific outcome resulting from the entity’s performance to achieve the milestone, (2) the consideration relates solely to past performance, and (3) the consideration is reasonable relative to all of the deliverables and payment terms within the arrangement. A milestone is defined as an event (i) that can only be achieved based in whole or in part on either the entity’s performance or on the occurrence of a specific outcome resulting from the entity’s performance, (ii) for which there is substantive uncertainty at the date the arrangement is entered into that the event will be achieved and (iii) that would result in additional payments being due to the Company.
	Contract Services, Grant and Royalty Revenue
	The Company recognizes revenues from contract services and federal government research grants during the period in which the related expenditures are incurred and related payments for those services are received or collection is reasonably assured. Royalties to be received based on sales of licensed products by the Company’s partners incorporating the Company’s licensed technology are recognized when received.
	Net Loss Per Share
	Basic and diluted net loss per share has been computed using the weighted-average number of shares of common stock outstanding during the period. The weighted average number of shares used to compute diluted net loss per share excludes any assumed exercise of stock options and warrants, and any assumed issuance of common stock under restricted stock units as the effect would be antidilutive. Common stock equivalents of 0.7 million and 1.6 million for the three months ended September 30, 2013 and 2012, respectively, were excluded from the calculation because of their antidilutive effect. Common stock equivalents of 1.2 million and 1.5 million for the nine months ended September 30, 2013 and 2012, respectively, were excluded from the calculation because of their antidilutive effect.
	Recent Accounting Pronouncement
	Effective January 1, 2013, the Company adopted Accounting Standards Update, or ASU, No. 2013-02, “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income.” The adoption of ASU No. 2013-02 concerns presentation and disclosure only and did not have an impact on the Company’s financial position or results of operations. The Company elected to present the information required by ASU No. 2013-02 in the Statements of Comprehensive Loss.

StockBased_Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Stock-Based Compensation	'
	2.       STOCK-BASED COMPENSATION
	Total stock-based compensation expense was allocated to research and development, manufacturing and production and general and administrative expense as follows (in thousands):
		Three Months  Ended				Nine Months  Ended
		September 30,				September 30,
		2013		2012		2013		2012
	Research and development	$	155	$	245	$	709	$	803
	Manufacturing and production		68		53		196		158
	General and administrative		509		437		1,781		1,617
	Total stock-based compensation expense	$	732	$	735	$	2,686	$	2,578
	During the nine months ended September 30, 2013 and 2012, the Company granted stock-based awards with a total estimated value of $4.8 million and $3.9 million, respectively. At September 30, 2013, total unrecognized estimated compensation expense related to unvested stock-based awards granted prior to that date was $3.9 million, which is expected to be recognized over a weighted-average period of 1.3 years. Stock-based awards granted during the nine months ended September 30, 2013 and 2012, were equal to 3.8% and 2.2%, respectively, of the outstanding shares of common stock at the end of the applicable period.

Other_Balance_Sheet_Accounts

Other Balance Sheet Accounts	9 Months Ended
	Sep. 30, 2013
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'
Other Balance Sheet Accounts	'
	3.       OTHER BALANCE SHEET ACCOUNTS
	Accounts payable and accrued expenses consisted of the following (in thousands):
		September 30,		December 31,
		2013		2012
	Employee compensation	$	2,356	$	3,858
	Post-termination benefit accrual		767		—
	Clinical trial accrual		656		660
	Accounts payable		574		377
	Deferred rent		353		307
	Other accrued liabilities		467		427
	Total accounts payable and accrued expenses	$	5,173	$	5,629

Marketable_Securities_Availabl

Marketable Securities, Available for Sale	9 Months Ended
	Sep. 30, 2013
Investments Debt And Equity Securities [Abstract]	'
Marketable Securities, Available for Sale	'
	4.       MARKETABLE SECURITIES, AVAILABLE FOR SALE
	The following is a summary of available-for-sale marketable securities (in thousands):
	September 30, 2013	Amortized		Unrealized		Unrealized		Market
		Cost		Gain		Loss		Value
	U.S. treasuries	$	4,008	$	4	$	—	$	4,012
	Government-sponsored enterprise securities		7,000		—		—		7,000
	Corporate bonds		4,856		—		3		4,853
	Certificates of deposit		1,171		—		—		1,171
		$	17,035	$	4	$	3	$	17,036
	December 31, 2012	Amortized		Unrealized		Unrealized		Market
		Cost		Gain		Loss		Value
	U.S. treasuries	$	10,135	$	1	$	—	$	10,136
	Government-sponsored enterprise securities		15,507		—		1		15,506
	Corporate bonds		11,509		—		8		11,501
	Certificates of deposit		496		—		—		496
		$	37,647	$	1	$	9	$	37,639
	At September 30, 2013, $7.0 million of these securities were scheduled to mature outside of one year. The Company did not realize any gains or losses on sales of available-for-sale securities for the nine months ended September 30, 2013. As of September 30, 2013, none of the securities had been in a continuous material unrealized loss position longer than one year.

LongTerm_Investments

Long-Term Investments	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Long-Term Investments	'
	5.       LONG-TERM INVESTMENTS
	In March 2012, the Company sold two auction rate securities classified as long-term investments with a par value of $4.0 million. Included in interest and other income for the nine months ended September 30, 2012, is a gain of $0.3 million related to the sale.
	As of September 30, 2013, the Company held an auction rate security with a par value of $2.5 million. This auction rate security has not experienced a successful auction since the liquidity issues experienced in the global credit and capital markets in 2008. As a result, the security is classified as a long-term investment as it is scheduled to mature in 2038. The security was rated BBB by Standard and Poor’s as of September 30, 2013. The security continues to pay interest according to its stated terms.
	The valuation of the Company’s auction rate security is subject to uncertainties that are difficult to predict. The fair value of the security is estimated utilizing a discounted cash flow analysis. The key drivers of the valuation model include the expected term, collateralization underlying the security investment, the creditworthiness of the counterparty, the timing of expected future cash flows, discount rates, liquidity and the expected holding period. The security was also compared, when possible, to other observable market data for securities with similar characteristics. Based on the valuation of the security, the Company has recognized cumulative losses of $0.5 million as of September 30, 2013. The losses when recognized are included in investment and other income. The market value of the security has partially recovered. Included in other comprehensive income are unrealized (losses) gains of $(0.2) million and $0.1 million for the nine months ended September 30, 2013 and 2012, respectively. As of September 30, 2013, the Company had recorded cumulative unrealized gains of $0.2 million. The resulting carrying value of the auction rate security at September 30, 2013, was $2.0 million. Any future decline in market value may result in additional losses being recognized.

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	6.       FAIR VALUE MEASUREMENTS
	The Company measures fair value as an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. Fair value measurements are based on a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows:
		•		Level 1: Observable inputs such as quoted prices in active markets;
		•		Level 2: Inputs, other than the quoted prices in active markets, that are observable either directly or indirectly; and
		•		Level 3: Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions.
	Cash equivalents, marketable securities and long-term investments measured at fair value are classified in the table below in one of the three categories described above (in thousands):
			Fair Value Measurements
	September 30, 2013		Level 1			Level 2		Level 3		Total
	Certificates of deposit		$	1,171		$	—	$	—	$	1,171
	Money market funds			12,774			—		—		12,774
	U.S. treasuries			4,012			—		—		4,012
	Corporate bonds			—			4,853		—		4,853
	Government-sponsored enterprise securities			—			7,000		—		7,000
	Auction rate securities			—			—		2,039		2,039
			$	17,957		$	11,853	$	2,039	$	31,849
			Fair Value Measurements
	December 31, 2012		Level 1			Level 2		Level 3		Total
	Certificates of deposit		$	496		$	—	$	—	$	496
	Money market funds			18,500			—		—		18,500
	U.S. treasuries			10,136			—		—		10,136
	Corporate bonds			—			11,501		—		11,501
	Government-sponsored enterprise securities			—			15,506		—		15,506
	Auction rate securities			—			—		2,225		2,225
			$	29,132		$	27,007	$	2,225	$	58,364
	The Company’s investments in U.S. treasury securities, certificates of deposit and money market funds are valued based on publicly available quoted market prices for identical securities as of September 30, 2013. The Company determines the fair value of corporate bonds and other government-sponsored enterprise related securities with the aid of valuations provided by third parties using proprietary valuation models and analytical tools. These valuation models and analytical tools use market pricing or similar instruments that are both objective and publicly available, including matrix pricing or reported trades, benchmark yields, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids and/or offers. The Company validates the valuations received from its primary pricing vendors for its level 2 securities by examining the inputs used in that vendor’s pricing process and determines whether they are reasonable and observable. The Company also compares those valuations to recent reported trades for those securities. The Company did not adjust any of the valuations received from these independent third parties with respect to any of its level 2 securities at September 30, 2013. The Company did not reclassify any investments between level categories during the three months ended September 30, 2013. The valuation of the Company’s investments in auction rate securities, which includes significant unobservable inputs, is more fully described in Note 5.
	Activity for assets measured at fair value using significant unobservable inputs (Level 3) is presented in the table below (in thousands):
			Nine Months
			Ended
			September 30, 2013
	Balance at December 31, 2012		$	2,225
	Total net unrealized losses, excluding tax impact, included in other comprehensive income			(186	)
	Balance at September 30, 2013		$	2,039
	Total gains or losses for the period included in net loss attributable to the change in unrealized gains or losses relating to assets still held at the reporting date		$	—

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	7.       COMMITMENTS AND CONTINGENCIES
	The Company prosecutes its intellectual property estate vigorously to obtain the broadest valid scope for its patents. Due to uncertainty of the ultimate outcome of patent enforcement actions, their impact on future operating results or the Company’s financial condition is not subject to reasonable estimates.
	In the ordinary course of business, the Company may become a party to lawsuits involving various matters. As of September 30, 2013, the Company was unaware of any such lawsuits pending against it which, individually or in the aggregate, were deemed to be material to the Company’s financial condition or results of operations. See Note 11.

Stockholders_Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2013
Equity [Abstract]	'
Stockholders' Equity	'
	8.       STOCKHOLDERS’ EQUITY
	In January 2012, the Company sold 13,333,334 shares of its common stock in a public offering at a price to the public of $3.75 per share. In February 2012, the Company sold an additional 576,358 shares pursuant to a partial exercise of the underwriters’ overallotment option at a price to the public of $3.75 per share. Net proceeds from the offering, after deducting underwriting discounts and commissions and other offering expenses payable by the Company, totaled $48.7 million. All of the shares of common stock were offered pursuant to two effective shelf registration statements.
	In November 2012, the Company entered into an At-The-Market Equity Offering Sales Agreement, or Sales Agreement, with Stifel, Nicolaus & Company, Incorporated, or Stifel, under which the Company may issue and sell up to $50,000,000 of shares of its common stock from time to time. Under the Sales Agreement, the Company will set the parameters for the sale of shares, including the number of shares to be issued and any minimum price below which sales may not be made. Subject to the terms and conditions of the Sales Agreement, shares may be sold through Stifel acting as sales agent or directly to Stifel acting as principal, by means of ordinary brokers’ transactions on the Nasdaq Global Select Market, in privately negotiated transactions or otherwise at market prices prevailing at the time of sale, at prices related to prevailing market prices or at negotiated prices. No shares of common stock have been sold under the Sales Agreement as of September 30, 2013.

Astellas_Agreements

Astellas Agreements	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Astellas Agreements	'
	9.       ASTELLAS AGREEMENTS
	In July 2011, the Company entered into license agreements with Astellas Pharma Inc., or Astellas, granting Astellas exclusive, worldwide, royalty-bearing licenses under certain of the Company’s know-how and intellectual property to develop and commercialize certain products containing plasmids encoding certain forms of cytomegalovirus, glycoprotein B and/or phosphoprotein 65, including ASP0113 (TransVax™) but excluding CyMVectin™.
	Under the terms of the license agreements, Astellas paid a nonrefundable upfront license fee of $25.0 million in 2011. The Company also received a $10.0 million milestone payment in March 2012 upon finalization of the general trial design for a Phase 3 registration trial of ASP0113 in hematopoietic stem cell transplant recipients. The Company recognized $0.4 million and $10.5 million in license revenue under the Astellas agreements during the nine months ended September 30, 2013 and 2012, respectively.
	Under the terms of the agreements, the Company is also performing research and development services which are being paid for by Astellas. During the three and nine months ended September 30, 2013, the Company recognized $1.2 million and $3.4 million, respectively, of revenue related to these contract services. During the three and nine months ended September 30, 2012, the Company recognized $1.6 million and $3.9 million, respectively, of revenue related to these contract services.
	In August 2012, the Company amended its license and supply agreements with Astellas to, among other things, extend the time period that the Company is obligated to supply licensed products for commercial use to Astellas, at Astellas’ expense, modify the allocation of $95.0 million of milestone payments among certain milestones through commercial launch and modify the structure of the royalties on net sales from a fixed double digit royalty to tiered double digit royalties.

Restructuring_Costs

Restructuring Costs	9 Months Ended
	Sep. 30, 2013
Restructuring And Related Activities [Abstract]	'
Restructuring Costs	'
	10.     RESTRUCTURING COSTS
	In August 2013, the Company announced that its recently completed Phase 3 clinical trial of Allovectin®, the Company’s investigational cancer immunotherapy, failed to meet the pre-established endpoints. As a result, the Company restructured its operations to conserve capital, which included a staff reduction of 47 employees and the write-off of certain intangible assets. The Company recorded charges for employee termination benefits of $2.2 million and for asset impairments of $0.7 million during the three months ended September 30, 2013. The following table summarizes the components of the restructuring charges for the three and nine months ended September 30, 2013 (in thousands):
		Three and Nine Months Ended
		September 30, 2013
		Accruals			Non-Cash		Total
					Items
	Employee separation charges	$	2,208		$	—	$	2,208
	Asset impairments		—			696		696
		$	2,208		$	696	$	2,904
	The following table sets forth activity in the restructuring liability for the nine months ended September 30, 2013, which is wholly comprised of employee severance costs (in thousands):
		Accrued
		Severance
	Balance at December 31, 2012	$	—
	Accruals		2,208
	Payments	$	(1,611	)
	Balance at September 30, 2013	$	597
	The balance of the accrued severance liability at September 30, 2013 is anticipated to be fully distributed by August 23, 2014.

Subsequent_Events

Subsequent Events	9 Months Ended
	Sep. 30, 2013
Subsequent Events [Abstract]	'
Subsequent Events	'
	11.      SUBSEQUENT EVENTS
	In October 2013, following the Company’s announcement of the results of its Phase 3 trial of Allovectin® and the subsequent decline of the price of its common stock, a complaint was filed, on behalf of certain purchasers of the Company’s common stock, in the U.S. District Court for the Southern District of California against the Company and certain of the Company’s current and former officers. The complaint includes claims asserted under Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, as amended, and has been brought as a purported shareholder class action. In general, the complaint alleges that the defendants violated the federal securities laws by making materially false and misleading statements regarding the Company’s business and prospects for Allovectin®, thereby artificially inflating the price of the Company’s common stock. The plaintiff is seeking unspecified monetary damages and other relief. The Company plans to vigorously defend against the claims advanced.

General_Policies

General (Policies)	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]	'
Cash, Cash Equivalents and Marketable Securities	'
	Cash, Cash Equivalents and Marketable Securities
	Cash and cash equivalents consist of cash and highly liquid securities with original maturities at the date of acquisition of ninety days or less. Investments with an original maturity of more than ninety days are considered marketable securities and have been classified by management as available-for-sale. These investments are classified as current assets, even though the stated maturity date may be one year or more beyond the current balance sheet date which reflects management’s intention to use the proceeds from sales of these securities to fund its operations, as necessary. Such investments are carried at fair value, with unrealized gains and losses included as a separate component of stockholders’ equity. Realized gains and losses from the sale of available-for-sale securities or the amounts, net of tax, reclassified out of accumulated other comprehensive income, if any, are determined on a specific identification basis.
Restricted Cash	'
	Restricted Cash
	The Company is required to maintain a letter of credit securing an amount equal to twelve months of the current monthly installment of base rent for the term of its primary facilities lease, which ends in August 2017. Under certain circumstances, the Company may be able to eliminate the need for the letter of credit. As of September 30, 2013, and December 31, 2012, restricted cash of $3.1 million was pledged as collateral for this letter of credit.
Revenue Recognition	'
	Revenue Recognition
	Revenue is recognized when the four basic criteria of revenue recognition are met: (1) persuasive evidence of an arrangement exists; (2) delivery has occurred or services rendered; (3) the fee is fixed or determinable; and (4) collectability is reasonably assured. Certain of the Company’s revenue is generated through manufacturing contracts and stand-alone license agreements.
	The Company has entered into multiple-element arrangements. In order to account for the multiple-element arrangements, the Company identifies the deliverables included within the agreement and evaluates which deliverables represent separate units of accounting. Analyzing the arrangement to identify deliverables requires the use of judgment, and each deliverable may be an obligation to deliver services, a right or license to use an asset, or another performance obligation.
	The delivered item(s) must have value to the customer on a standalone basis and, if the arrangement includes a general right of return relative to the delivered item, delivery or performance of the undelivered item(s) is considered probable and substantially in the Company’s control.
	A delivered item is considered a separate unit of accounting when the delivered item has value to the partner on a standalone basis based on the consideration of the relevant facts and circumstances for each arrangement. Factors considered in this determination include the research capabilities of the partner and the availability of research expertise in this field in the general marketplace. Arrangement consideration is allocated at the inception of the agreement to all identified units of accounting based on their relative selling price. The relative selling price for each deliverable is determined using vendor specific objective evidence, or VSOE, of selling price or third-party evidence of selling price if VSOE does not exist. If neither VSOE nor third-party evidence of selling price exists, the Company uses its best estimate of the selling price for the deliverable. The amount of allocable arrangement consideration is limited to amounts that are fixed or determinable. The consideration received is allocated among the separate units of accounting, and the applicable revenue recognition criteria are applied to each of the separate units. Changes in the allocation of the sales price between delivered and undelivered elements can impact revenue recognition but do not change the total revenue recognized under any agreement. If facts and circumstances dictate that the license has standalone value from the undelivered items, which generally include research and development services and the manufacture of drug products, the license is identified as a separate unit of accounting and the amounts allocated to the license are recognized upon the delivery of the license, assuming the other revenue recognition criteria have been met. However, if the amounts allocated to the license through the relative selling price allocation exceed the upfront license fee, the amount recognized upon the delivery of the license is limited to the upfront fee received. If facts and circumstances dictate that the license does not have standalone value, the transaction price, including any upfront license fee payments received, are allocated to the identified separate units of accounting and recognized as those items are delivered.
	The terms of the Company’s partnership agreements provide for milestone payments upon achievement of certain regulatory and commercial events. The Company recognizes consideration that is contingent upon the achievement of a milestone in its entirety as revenue in the period in which the milestone is achieved only if the milestone is substantive in its entirety. A milestone is considered substantive when it meets all of the following three criteria: (1) the consideration is commensurate with either the entity’s performance to achieve the milestone or the enhancement of the value of the delivered item(s) as a result of a specific outcome resulting from the entity’s performance to achieve the milestone, (2) the consideration relates solely to past performance, and (3) the consideration is reasonable relative to all of the deliverables and payment terms within the arrangement. A milestone is defined as an event (i) that can only be achieved based in whole or in part on either the entity’s performance or on the occurrence of a specific outcome resulting from the entity’s performance, (ii) for which there is substantive uncertainty at the date the arrangement is entered into that the event will be achieved and (iii) that would result in additional payments being due to the Company.
Contract Services, Grant and Royalty Revenue	'
	Contract Services, Grant and Royalty Revenue
	The Company recognizes revenues from contract services and federal government research grants during the period in which the related expenditures are incurred and related payments for those services are received or collection is reasonably assured. Royalties to be received based on sales of licensed products by the Company’s partners incorporating the Company’s licensed technology are recognized when received.
Net Loss Per Share	'
	Net Loss Per Share
	Basic and diluted net loss per share has been computed using the weighted-average number of shares of common stock outstanding during the period. The weighted average number of shares used to compute diluted net loss per share excludes any assumed exercise of stock options and warrants, and any assumed issuance of common stock under restricted stock units as the effect would be antidilutive. Common stock equivalents of 0.7 million and 1.6 million for the three months ended September 30, 2013 and 2012, respectively, were excluded from the calculation because of their antidilutive effect. Common stock equivalents of 1.2 million and 1.5 million for the nine months ended September 30, 2013 and 2012, respectively, were excluded from the calculation because of their antidilutive effect.
Recent Accounting Pronouncement	'
	Recent Accounting Pronouncement
	Effective January 1, 2013, the Company adopted Accounting Standards Update, or ASU, No. 2013-02, “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income.” The adoption of ASU No. 2013-02 concerns presentation and disclosure only and did not have an impact on the Company’s financial position or results of operations. The Company elected to present the information required by ASU No. 2013-02 in the Statements of Comprehensive Loss.

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Summary of Total Stock-Based Compensation Expense	'
	Total stock-based compensation expense was allocated to research and development, manufacturing and production and general and administrative expense as follows (in thousands):
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2013		2012		2013		2012
	Research and development	$	155	$	245	$	709	$	803
	Manufacturing and production		68		53		196		158
	General and administrative		509		437		1,781		1,617
	Total stock-based compensation expense	$	732	$	735	$	2,686	$	2,578

Other_Balance_Sheet_Accounts_T

Other Balance Sheet Accounts (Tables)	9 Months Ended
	Sep. 30, 2013
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'
Summary of Accounts Payable and Accrued Expenses	'
	Accounts payable and accrued expenses consisted of the following (in thousands):
		September 30,		December 31,
		2013		2012
	Employee compensation	$	2,356	$	3,858
	Post-termination benefit accrual		767		—
	Clinical trial accrual		656		660
	Accounts payable		574		377
	Deferred rent		353		307
	Other accrued liabilities		467		427
	Total accounts payable and accrued expenses	$	5,173	$	5,629

Marketable_Securities_Availabl1

Marketable Securities, Available for Sale (Tables)	9 Months Ended
	Sep. 30, 2013
Investments Debt And Equity Securities [Abstract]	'
Summary of Available-for-Sale Marketable Securities	'
	The following is a summary of available-for-sale marketable securities (in thousands):
	September 30, 2013	Amortized		Unrealized		Unrealized		Market
		Cost		Gain		Loss		Value
	U.S. treasuries	$	4,008	$	4	$	—	$	4,012
	Government-sponsored enterprise securities		7,000		—		—		7,000
	Corporate bonds		4,856		—		3		4,853
	Certificates of deposit		1,171		—		—		1,171
		$	17,035	$	4	$	3	$	17,036
	December 31, 2012	Amortized		Unrealized		Unrealized		Market
		Cost		Gain		Loss		Value
	U.S. treasuries	$	10,135	$	1	$	—	$	10,136
	Government-sponsored enterprise securities		15,507		—		1		15,506
	Corporate bonds		11,509		—		8		11,501
	Certificates of deposit		496		—		—		496
		$	37,647	$	1	$	9	$	37,639

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Summary of Cash Equivalents, Marketable Securities and Long-Term Investments Measured at Fair Value	'
	Cash equivalents, marketable securities and long-term investments measured at fair value are classified in the table below in one of the three categories described above (in thousands):
		Fair Value Measurements
	September 30, 2013	Level 1			Level 2		Level 3		Total
	Certificates of deposit	$	1,171		$	—	$	—	$	1,171
	Money market funds		12,774			—		—		12,774
	U.S. treasuries		4,012			—		—		4,012
	Corporate bonds		—			4,853		—		4,853
	Government-sponsored enterprise securities		—			7,000		—		7,000
	Auction rate securities		—			—		2,039		2,039
		$	17,957		$	11,853	$	2,039	$	31,849
		Fair Value Measurements
	December 31, 2012	Level 1			Level 2		Level 3		Total
	Certificates of deposit	$	496		$	—	$	—	$	496
	Money market funds		18,500			—		—		18,500
	U.S. treasuries		10,136			—		—		10,136
	Corporate bonds		—			11,501		—		11,501
	Government-sponsored enterprise securities		—			15,506		—		15,506
	Auction rate securities		—			—		2,225		2,225
		$	29,132		$	27,007	$	2,225	$	58,364
Summary of Activity for Assets Measured at Fair Value Using Significant Unobservable Inputs	'
	Activity for assets measured at fair value using significant unobservable inputs (Level 3) is presented in the table below (in thousands):
		Nine Months
		Ended
		September 30,
		2013
	Balance at December 31, 2012	$	2,225
	Total net unrealized losses, excluding tax impact, included in other comprehensive income		(186	)
	Balance at September 30, 2013	$	2,039
	Total gains or losses for the period included in net loss attributable to the change in unrealized gains or losses relating to assets still held at the reporting date	$	—

Restructuring_Costs_Tables

Restructuring Costs (Tables)	9 Months Ended
	Sep. 30, 2013
Restructuring And Related Activities [Abstract]	'
Summary of Components of Restructuring Charges	'
	The following table summarizes the components of the restructuring charges for the three and nine months ended September 30, 2013 (in thousands):
		Three and Nine Months Ended
		September 30, 2013
		Accruals			Non-Cash		Total
					Items
	Employee separation charges	$	2,208		$	—	$	2,208
	Asset impairments		—			696		696
		$	2,208		$	696	$	2,904
Schedule of Restructuring Liability	'
	The following table sets forth activity in the restructuring liability for the nine months ended September 30, 2013, which is wholly comprised of employee severance costs (in thousands):
		Accrued
		Severance
	Balance at December 31, 2012	$	—
	Accruals		2,208
	Payments	$	(1,611	)
	Balance at September 30, 2013	$	597

General_Additional_Information

General - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data in Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'	'	'	'	'
Maximum period for cash and highly liquid securities with original maturities	'	'	'ninety days or less	'	'
Minimum period for marketable securities classified as available-for-sale with original maturities	'	'	'more than ninety days	'	'
Amount of letter of credit, description	'	'	'The Company is required to maintain a letter of credit securing an amount equal to twelve months of the current monthly installment of base rent for the term of its primary facilities lease, which ends in August 2017.	'	'
Restricted cash	$3,119	'	$3,119	'	$3,059
Common stock equivalents excluded from the calculation of diluted net loss per share	0.7	1.6	1.2	1.5	'

StockBased_Compensation_Summar

Stock-Based Compensation - Summary of Total Stock-Based Compensation Expense (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Total stock-based compensation expense	$732	$735	$2,686	$2,578
Research and development [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Total stock-based compensation expense	155	245	709	803
Manufacturing and production [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Total stock-based compensation expense	68	53	196	158
General and administrative [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Total stock-based compensation expense	$509	$437	$1,781	$1,617

StockBased_Compensation_Additi

Stock-Based Compensation - Additional Information (Detail) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'	'
Estimated value of stock-based awards, granted	$4.80	$3.90
Unrecognized compensation cost related to unvested options	$3.90	'
Unvested stock-based awards expected to be recognized, weighted-average period	'1 year 3 months 18 days	'
Portion of stock-based awards granted from outstanding common shares	3.80%	2.20%

Other_Balance_Sheet_Accounts_S

Other Balance Sheet Accounts - Summary of Accounts Payable and Accrued Expenses (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Payables And Accruals [Abstract]	'	'
Employee compensation	$2,356	$3,858
Post-termination benefit accrual	767	'
Clinical trial accrual	656	660
Accounts payable	574	377
Deferred rent	353	307
Other accrued liabilities	467	427
Total accounts payable and accrued expenses	$5,173	$5,629

Marketable_Securities_Availabl2

Marketable Securities, Available for Sale - Summary of Available-for-Sale Marketable Securities (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	$17,035	$37,647
Unrealized Gain	4	1
Unrealized Loss	3	9
Market Value	17,036	37,639
U.S. treasuries [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	4,008	10,135
Unrealized Gain	4	1
Unrealized Loss	'	'
Market Value	4,012	10,136
Government-sponsored enterprise securities [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	7,000	15,507
Unrealized Gain	'	'
Unrealized Loss	'	1
Market Value	7,000	15,506
Corporate bonds [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	4,856	11,509
Unrealized Gain	'	'
Unrealized Loss	3	8
Market Value	4,853	11,501
Certificates of deposit [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	1,171	496
Unrealized Gain	'	'
Unrealized Loss	'	'
Market Value	$1,171	$496

Marketable_Securities_Availabl3

Marketable Securities, Available for Sale - Additional Information (Detail) (USD $)	9 Months Ended
	Sep. 30, 2013
Investments Debt And Equity Securities [Abstract]	'
Available-for-sale securities maturing outside of one year	$7,000,000
Realized gains or losses on sales of available-for-sale securities	0
Available-for-sale securities in a continuous material loss position longer than one year	$0

LongTerm_Investments_Additiona

Long-Term Investments - Additional Information (Detail) (USD $)	1 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2012	Sep. 30, 2013	Sep. 30, 2012
	Investment
Investments Schedule [Abstract]	'	'	'
Number of long-term investments sold during the period	2	'	'
Auction rate securities sold, at par value	$4	'	'
Gain related to auction rate securities	'	'	0.3
Auction rate securities held, at par value	'	2.5	'
Maturity of long-term investment	'	'2038	'
Recognized cumulative losses	'	0.5	'
Unrealized (losses) gains on auction rate securities	'	-0.2	0.1
Cumulative unrealized gains	'	0.2	'
Carrying value of auction rate security	'	$2	'

Fair_Value_Measurements_Summar

Fair Value Measurements - Summary of Cash Equivalents, Marketable Securities and Long-Term Investments Measured at Fair Value (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	$31,849	$58,364
Certificates of deposit [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	1,171	496
Money market funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	12,774	18,500
U.S. treasuries [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	4,012	10,136
Corporate bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	4,853	11,501
Government-sponsored enterprise securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	7,000	15,506
Auction rate securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	2,039	2,225
Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	17,957	29,132
Level 1 [Member] | Certificates of deposit [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	1,171	496
Level 1 [Member] | Money market funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	12,774	18,500
Level 1 [Member] | U.S. treasuries [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	4,012	10,136
Level 1 [Member] | Corporate bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	'	'
Level 1 [Member] | Government-sponsored enterprise securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	'	'
Level 1 [Member] | Auction rate securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	'	'
Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	11,853	27,007
Level 2 [Member] | Certificates of deposit [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	'	'
Level 2 [Member] | Money market funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	'	'
Level 2 [Member] | U.S. treasuries [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	'	'
Level 2 [Member] | Corporate bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	4,853	11,501
Level 2 [Member] | Government-sponsored enterprise securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	7,000	15,506
Level 2 [Member] | Auction rate securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	'	'
Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	2,039	2,225
Level 3 [Member] | Certificates of deposit [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	'	'
Level 3 [Member] | Money market funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	'	'
Level 3 [Member] | U.S. treasuries [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	'	'
Level 3 [Member] | Corporate bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	'	'
Level 3 [Member] | Government-sponsored enterprise securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	'	'
Level 3 [Member] | Auction rate securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value	$2,039	$2,225

Fair_Value_Measurements_Summar1

Fair Value Measurements - Summary of Activity for Assets Measured at Fair Value Using Significant Unobservable Inputs (Detail) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Balance at December 31, 2012	$2,225
Total net unrealized losses, excluding tax impact, included in other comprehensive income	-186
Balance at September 30, 2013	2,039
Total gains or losses for the period included in net loss attributable to the change in unrealized gains or losses relating to assets still held at the reporting date	'

Stockholders_Equity_Additional

Stockholders' Equity - Additional Information (Detail) (USD $)	1 Months Ended
	Feb. 29, 2012	Jan. 31, 2012	Nov. 30, 2012
Equity [Abstract]	'	'	'
Number of shares of common stock sold in public offering	'	13,333,334	'
Common stock, public offering price	$3.75	$3.75	'
Net proceeds from offering	'	$48,700,000	'
Number of common stock issued on partial exercise of underwriters' overallotment option	576,358	'	'
Maximum value of common stock issuable under agreement	'	'	$50,000,000

Astellas_Agreements_Additional

Astellas Agreements - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Aug. 31, 2012	Sep. 30, 2013	Sep. 30, 2012	Mar. 31, 2012	Mar. 31, 2011	Sep. 30, 2013	Sep. 30, 2012
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'	'	'	'	'	'	'
Recognized license revenue	'	'	'	'	$25	$0.40	$10.50
Additional amount received upon finalization of the general trial design	'	'	'	10	'	'	'
Recognized revenue related to contract services	'	1.2	1.6	'	'	3.4	3.9
Amount payable under license agreement on achievement of milestone	$95	'	'	'	'	'	'

Restructuring_Costs_Additional

Restructuring Costs - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended
In Millions, unless otherwise specified	Aug. 31, 2013	Sep. 30, 2013
	Employees
Restructuring And Related Activities [Abstract]	'	'
Charges for employee termination benefits	'	$2.20
Asset impairments	'	$0.70
Restructured of employees to converse capital include a staff reduction of employees	47	'

Restructuring_Costs_Summary_of

Restructuring Costs - Summary of Components of Restructuring Charges (Detail) (USD $)	3 Months Ended	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013
Restructuring Cost and Reserve [Line Items]	'	'
Accruals	$2,208	$2,208
Non-Cash Items	696	696
Total	2,904	2,904
Employee separation charges [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Accruals	2,208	2,208
Non-Cash Items	'	'
Total	2,208	2,208
Asset impairments [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Accruals	'	'
Non-Cash Items	696	696
Total	$696	$696

Restructuring_Costs_Schedule_o

Restructuring Costs - Schedule of Restructuring Liability (Detail) (USD $)	3 Months Ended	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013
Restructuring Cost and Reserve [Line Items]	'	'
Accruals	$2,208	$2,208
Accrued Severance [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Beginning balance	'	'
Accruals	'	2,208
Payments	'	-1,611
Ending balance	$597	$597