Aceragen (ACGN) 10-K13 Mar 142013 FY Annual reportFinancial data

Company Profile

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
Document and Entity Information (USD $)	Dec. 31, 2013	Feb. 15, 2014	Jun. 28, 2013
Document And Entity Information [Abstract]	'	'	'
Document Type	'10-K	'	'
Amendment Flag	'false	'	'
Document Period End Date	31-Dec-13	'	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'FY	'	'
Entity Registrant Name	'IDERA PHARMACEUTICALS, INC.	'	'
Entity Central Index Key	'0000861838	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Well-known Seasoned Issuer	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Filer Category	'Non-accelerated Filer	'	'
Entity Common Stock, Shares Outstanding	'	82,360,165	'
Entity Public Float	'	'	$25,882,078

Balance_Sheets

Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Current assets:	'	'
Cash and cash equivalents	$26,278	$10,096
Short-term investments	3,125	'
Prepaid expenses and other current assets	874	198
Total current assets	30,277	10,294
Long-term investments	6,189	'
Property and equipment, net	90	218
Restricted cash	311	311
Total assets	36,867	10,823
Current liabilities:	'	'
Accounts payable	904	1,129
Accrued expenses	3,506	3,002
Total current liabilities	4,410	4,131
Other liabilities	5	65
Total liabilities	4,415	4,196
Commitments and contingencies (Note 9)	'	'
Series D Redeemable Convertible Preferred Stock, $0.01 par value, Designated, issued and outstanding - 1,124 shares at December 31, 2012	'	5,921
Non-redeemable Preferred Stock, Common Stock, and Other Stockholders' equity:	'	'
Preferred stock, $0.01 par value, Authorized - 5,000 shares:	'	'
Common stock, $0.001 par value, Authorized - 280,000 and 140,000 shares at December 31, 2013,and 2012, respectively; Issued and outstanding - 66,252 and 27,643 shares at December 31, 2013 and 2012, respectively	66	28
Additional paid-in capital	434,285	391,635
Accumulated deficit	-412,884	-394,658
Accumulated other comprehensive loss	-7	'
Total stockholders' equity	32,452	706
Total liabilities, redeemable preferred stock and stockholders' equity	36,867	10,823
Series E Preferred Stock [Member]	'	'
Non-redeemable Preferred Stock, Common Stock, and Other Stockholders' equity:	'	'
Preferred stock, $0.01 par value	5,528	3,701
Total stockholders' equity	5,528	3,701
Series D Preferred Stock [Member]	'	'
Non-redeemable Preferred Stock, Common Stock, and Other Stockholders' equity:	'	'
Preferred stock, $0.01 par value	5,464	'
Total stockholders' equity	5,464	'
Series A Preferred Stock [Member]	'	'
Non-redeemable Preferred Stock, Common Stock, and Other Stockholders' equity:	'	'
Preferred stock, $0.01 par value	'	'

Balance_Sheets_Parenthetical

Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012
Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Series D Convertible Redeemable Preferred Stock [Member]	Series E Preferred Stock [Member]	Series E Preferred Stock [Member]	Series D Preferred Stock [Member]	Series A Preferred Stock [Member]	Series A Preferred Stock [Member]
Series D Redeemable convertible preferred stock, par value	'	'	$0.01	'	'	'	'	'
Series D Redeemable convertible preferred stock, shares designated	'	'	1,124,000	'	'	'	'	'
Series D Redeemable convertible preferred stock, shares issued	'	'	1,124,000	'	'	'	'	'
Series D Redeemable convertible preferred stock, shares outstanding	'	'	1,124,000	'	'	'	'	'
Preferred stock, shares authorized	5,000,000	5,000,000	'	'	'	'	'	'
Preferred stock, par value	'	'	'	$0.01	$0.01	$0.01	$0.01	$0.01
Preferred stock, shares designated	'	'	'	424,000	424,000	1,124,260	1,500,000	1,500,000
Preferred stock, shares issued	'	'	'	424,000	424,000	1,124,000	1,000	1,000
Preferred stock, shares outstanding	'	'	'	424,000	424,000	1,124,000	1,000	1,000
Common stock, par value	$0.00	$0.00	'	'	'	'	'	'
Common stock, shares authorized	280,000,000	140,000,000	'	'	'	'	'	'
Common stock, shares issued	66,252,000	27,643,000	'	'	'	'	'	'
Common stock, shares outstanding	66,252,000	27,643,000	'	424,000	424,000	1,124,000	'	'

Statements_of_Operations_and_C

Statements of Operations and Comprehensive Loss (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement Of Income And Comprehensive Income [Abstract]	'	'	'
Alliance revenue	$47	$51	$53
Operating expenses:	'	'	'
Research and development	10,475	13,673	17,969
General and administrative	7,741	6,279	7,939
Total operating expenses	18,216	19,952	25,908
Loss from operations	-18,169	-19,901	-25,855
Other income (expense):	'	'	'
Decrease in fair value of warrant liability	'	675	1,974
Investment income, net	11	9	30
Foreign currency exchange (loss) gain	-68	-23	75
Net loss	-18,226	-19,240	-23,776
Loss on extinguishment of convertible preferred stock, preferred stock accretion and dividends	2,866	3,210	4,548
Net loss applicable to common stockholders	-21,092	-22,450	-28,324
Basic and diluted net loss per common share applicable to common stockholders (Note 12)	($0.48)	($0.81)	($1.03)
Shares used in computing basic and diluted net loss per common share applicable to common stockholders	43,906	27,639	27,623
Net loss	-18,226	-19,240	-23,776
Other comprehensive loss:	'	'	'
Increase in unrealized loss and decrease in unrealized gain on available-for-sale securities	-7	'	-13
Other comprehensive loss	-7	'	-13
Comprehensive loss	($18,233)	($19,240)	($23,789)

Statements_of_Shareholders_Equ

Statements of Shareholders' Equity (USD $)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive (Loss)/Income [Member]	Series E Preferred Stock [Member]	Series D Preferred Stock [Member]
In Thousands, except Share data	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive (Loss)/Income [Member]	Series E Preferred Stock [Member]	Series D Preferred Stock [Member]
Beginning balance at Dec. 31, 2010	$33,101	$28	$384,702	($351,642)	$13	'	'
Beginning balance, shares at Dec. 31, 2010	'	27,596,000	'	'	'	'	'
Exercise of common stock options, warrants and employee stock purchases	51	'	51	'	'	'	'
Exercise of common stock options, warrants and employee stock purchases, shares	'	26,000	'	'	'	'	'
Issuance of common stock for services	38	'	38	'	'	'	'
Issuance of common stock for services, shares	'	15,000	'	'	'	'	'
Non-employee stock option expense	1	'	1	'	'	'	'
Stock-based compensation	2,725	'	2,725	'	'	'	'
Series D redeemable preferred stock beneficial conversion feature	4,445	'	4,445	'	'	'	'
Series D redeemable preferred stock accretion and dividends	-4,548	'	-4,548	'	'	'	'
Unrealized gain (loss) on marketable securities	-13	'	'	'	-13	'	'
Net loss	-23,776	'	'	-23,776	'	'	'
Ending balance at Dec. 31, 2011	12,024	28	387,414	-375,418	'	'	'
Ending balance, shares at Dec. 31, 2011	'	27,637,000	'	'	'	'	'
Exercise of common stock options, warrants and employee stock purchases	4	'	4	'	'	'	'
Exercise of common stock options, warrants and employee stock purchases, shares	'	5,000	'	'	'	'	'
Issuance of common stock for services	1	'	1	'	'	'	'
Issuance of common stock for services, shares	'	1,000	'	'	'	'	'
Non-employee stock option expense	5	'	5	'	'	'	'
Stock-based compensation	2,096	'	2,096	'	'	'	'
Series D redeemable preferred stock beneficial conversion feature	1,238	'	1,238	'	'	'	'
Series D redeemable preferred stock accretion and dividends	-1,908	'	-1,908	'	'	'	'
Transfer of Series D warrant to equity	503	'	503	'	'	'	'
Sale of Series E preferred stock and warrants, net of issuance costs	6,023	'	2,322	'	'	3,701	'
Sale of Series E preferred stock and warrants, net of issuance costs, shares	'	'	'	'	'	424,000	'
Series E preferred stock beneficial conversion feature	'	'	1,262	'	'	-1,262	'
Series E preferred stock accretion and dividends	-40	'	-1,302	'	'	1,262	'
Net loss	-19,240	'	'	-19,240	'	'	'
Ending balance at Dec. 31, 2012	706	28	391,635	-394,658	'	3,701	'
Ending balance, shares at Dec. 31, 2012	27,643,000	27,643,000	'	'	'	424,000	'
Sale of common stock and warrants, net of issuance costs	40,102	31	40,071	'	'	'	'
Sale of common stock and warrants, net of issuance costs, shares	'	31,227,000	'	'	'	'	'
Exercise of common stock options, warrants and employee stock purchases	3,527	7	3,520	'	'	'	'
Exercise of common stock options, warrants and employee stock purchases, shares	'	7,346,000	'	'	'	'	'
Issuance of common stock for services	26	'	26	'	'	'	'
Issuance of common stock for services, shares	'	36,000	'	'	'	'	'
Non-employee stock option expense	121	'	121	'	'	'	'
Stock-based compensation	1,398	'	1,398	'	'	'	'
Extinguishment of convertible preferred stock & recognition of warrants issued	-5,071	'	-1,370	'	'	-3,701	'
Extinguishment of convertible preferred stock & recognition of warrants issued, shares	'	'	'	'	'	-424,000	'
Recognition of convertible preferred stock	10,992	'	'	'	'	5,528	5,464
Recognition of convertible preferred stock, shares	'	'	'	'	'	424,000	1,124,000
Series D convertible preferred stock dividends	-756	'	-756	'	'	'	'
Series E convertible preferred stock dividends	-360	'	-360	'	'	'	'
Unrealized gain (loss) on marketable securities	-7	'	'	'	-7	'	'
Net loss	-18,226	'	'	-18,226	'	'	'
Ending balance at Dec. 31, 2013	$32,452	$66	$434,285	($412,884)	($7)	$5,528	$5,464
Ending balance, shares at Dec. 31, 2013	66,252,000	66,252,000	'	'	'	424,000	1,124,000

Statements_of_Cash_Flows

Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash Flows from Operating Activities:	'	'	'
Net loss	($18,226)	($19,240)	($23,776)
Adjustments to reconcile net loss to net cash used in operating activities -	'	'	'
Loss from disposition of assets	'	4	1
Non-employee stock option expense	121	5	1
Stock-based compensation	1,398	2,096	2,725
Cost of regaining rights to cancer program	'	'	2,423
Decrease in fair value of warrant liability	'	-675	-1,974
Issuance of common stock for services rendered	26	1	38
Amortization of investment premiums	9	'	62
Depreciation and amortization expense	137	251	494
Changes in operating assets and liabilities -	'	'	'
Prepaid expenses and other current assets	-676	57	640
Accounts payable, accrued expenses, and other liabilities	74	-2,415	174
Net cash used in operating activities	-17,137	-19,916	-19,192
Cash Flows from Investing Activities:	'	'	'
Purchases of available-for-sale securities	-9,331	'	-1,025
Proceeds from maturity of available-for-sale securities	'	'	18,585
Decrease in restricted cash	'	'	102
Purchases of property and equipment	-9	'	-23
Net cash (used in) provided by investing activities	-9,340	'	17,639
Cash Flows from Financing Activities:	'	'	'
Sale of common stock and warrants, net of issuance costs	40,202	'	'
Sale of Series E convertible preferred stock and warrants, net of issuance costs	'	6,023	'
Sale of Series D redeemable convertible preferred stock and warrants, net of issuance costs	'	'	9,073
Proceeds from exercise of common stock warrants and options and employee stock purchases	3,527	4	51
Dividends paid	-1,066	-583	'
Payments on capital lease	-4	-3	-8
Net cash provided by financing activities	42,659	5,441	9,116
Net increase (decrease) in cash and cash equivalents	16,182	-14,475	7,563
Cash and cash equivalents, beginning of year	10,096	24,571	17,008
Cash and cash equivalents, end of year	$26,278	$10,096	$24,571

Organization

Organization	12 Months Ended
Organization	Dec. 31, 2013
Accounting Policies [Abstract]	'
Organization	'
	1. Organization
	Idera Pharmaceuticals, Inc. (“Idera” or the “Company”) is a clinical stage biotechnology company advancing drug candidates for the treatment of autoimmune diseases and for certain genetically defined forms of B-cell lymphoma. These drug candidates are designed to inhibit over-activation of specific Toll-like receptors (“TLRs”). In addition to this TLR program, the Company has initiated a research program employing its gene silencing oligonucleotides (“GSOs”), to inhibit the production of disease-associated proteins by targeting RNA.
	The Company’s lead drug candidate in its TLR program is IMO-8400, an antagonist of TLR7, TLR8, and TLR9. IMO-8400 is in clinical development for the treatment of autoimmune diseases and certain genetically defined forms of B-cell lymphoma. The Company is also conducting preclinical studies of IMO-9200, a second antagonist of TLR7, TLR8, and TLR9, to support the submission of an Investigational New Drug application, or IND, to the United States Food and Drug Administration, (“FDA”). A TLR antagonist is a compound that blocks activation of an immune response through the targeted TLR.
	The Company’s business strategy is to develop IMO-8400, IMO-9200, and other TLR antagonist candidates for the treatment of certain genetically defined forms of B-cell lymphomas and for the treatment of autoimmune diseases with orphan indications. In addition, the Company may seek to enter into collaborative alliances with pharmaceutical companies to advance our TLR antagonist candidates in broader autoimmune disease indications, such as psoriasis, lupus, and arthritis.
	At December 31, 2013, the Company had an accumulated deficit of $412,884,000. The Company expects to incur substantial operating losses in future periods. The Company does not expect to generate significant product revenue, sales-based milestones or royalties until the Company successfully completes development and obtains marketing approval for drug candidates, either alone or in collaborations with third parties, which the Company expects will take a number of years. In order to commercialize its drug candidates, the Company needs to complete clinical development and to comply with comprehensive regulatory requirements.
	The Company is subject to a number of risks and uncertainties similar to those of other companies of the same size within the biotechnology industry, such as uncertainty of clinical trial outcomes, uncertainty of additional funding, and history of operating losses.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
Summary of Significant Accounting Policies	Dec. 31, 2013
Accounting Policies [Abstract]	'
Summary of Significant Accounting Policies	'
	2. Summary of Significant Accounting Policies
	(a) Basis of Presentation
	The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure 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 from those estimates.
	(b) Cash, Cash Equivalents and Investments
	The Company considers all highly liquid investments with maturities of 90 days or less when purchased to be “cash equivalents.” Cash and cash equivalents at December 31, 2013 and 2012 consisted of cash and money market funds.

	Management determines the appropriate classification of marketable securities at the time of purchase. Investments that the Company does not have the positive intent to hold to maturity are classified as “available-for-sale” and reported at fair market value. Available-for-sale investments are classified as long-term if their contractual maturity is greater than one year at the balance sheet date and the Company does not have the intent to sell them in order to fund current operations. Unrealized gains and losses associated with available-for-sale investments are recorded in “Accumulated other comprehensive income” on the accompanying balance sheets. The amortization of premiums and accretion of discounts, and any realized gains and losses and declines in value judged to be other-than-temporary, and interest and dividends for all available-for-sale securities are included in “Investment income, net” on the accompanying statements of operations. Investments that the Company intends to hold to maturity are classified as “held-to-maturity” investments. The Company had no “held-to-maturity” investments at either December 31, 2013 or 2012. The cost of securities sold is based on the specific identification method.
	The Company had no realized gains or losses from available-for-sale securities in 2013, 2012 or 2011. There were no losses or other-than-temporary declines in value included in “Investment income, net” for any securities for the three years ended December 31, 2013. The Company had no auction rate securities as of December 31, 2013 and 2012.
	(c) Restricted Cash
	As part of the Company’s lease arrangement for its office and laboratory facility, the Company is required to restrict cash held in a certificate of deposit securing a line of credit for the lessor. As of December 31, 2013 and 2012, the restricted cash amounted to $311,000 held in certificates of deposit securing a line of credit for the lessor. In February 2014, the lease term was extended to August 31, 2017. As a result, the restricted cash is included in non-current assets at December 31, 2013.
	(d) Depreciation and Amortization
	Depreciation and amortization are computed using the straight-line method based on the estimated useful lives of the related assets. Laboratory and other equipment are depreciated over three to five years. Leasehold improvements are amortized over the remaining lease term or the related useful life, if shorter.
	(e) Revenue Recognition
	For the years ended December 31, 2013, 2012 and 2011, alliance revenue consisted primarily of revenue from the reimbursement by licensees of costs associated with patent maintenance. The Company recognizes the reimbursement revenue during the period in which the related expenses are incurred.
	(f) Financial Instruments
	The fair value of the Company’s financial instruments is determined and disclosed in accordance with the three-tier fair value hierarchy specified in Note 2(m). The Company is required to disclose the estimated fair values of its financial instruments. The Company’s financial instruments consist of cash, cash equivalents, available-for-sale investments and receivables. The estimated fair values of these financial instruments approximate their carrying values as of December 31, 2013 and 2012, respectively. As of December 31, 2013 and 2012, the Company did not have any derivatives, hedging instruments or other similar financial instruments except for the Series D convertible preferred stock, the (“Series D preferred stock”), embedded features discussed in Note 7(a) and the Series E convertible preferred stock, the (“Series E preferred stock”) embedded features discussed in Note 8(g).

	(g) Comprehensive Income (Loss)
	Comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. Comprehensive income (loss) for the years ended December 31, 2013, 2012 and 2011 is comprised of reported net income (loss) and any change in net unrealized gains and losses on investments during each year, which is included in “Accumulated other comprehensive income” on the accompanying balance sheets. The Company applies ASU No. 2011-05, “Comprehensive Income” by presenting the components of net income and other comprehensive income as one continuous statement.
	The following table includes the changes in the accumulated balance of the component of other comprehensive (loss) gain for the years ended December 31, 2013 and 2011:


			Year ended December 31,
	(In thousands)		2013				2011
	Accumulated unrealized gain on available-for-sale securities at beginning of period		$	—			$	13
	Change during the period			(7	)			(13	)

	Accumulated unrealized loss on available-for-sale securities at end of period		$	(7	)		$	—

	There was no accumulated unrealized gain or loss on available-for-sale securities during 2012.
	(h) Net Income (Loss) per Common Share applicable to Common Stockholders
	Basic and diluted net loss per common share applicable to common stockholders is computed using the weighted average number of shares of common stock outstanding during the period. Diluted net loss per common share applicable to common stockholders is the same as basic net loss per common share applicable to common stockholders for each of the three years ended December 31, 2013 as the effects of the Company’s potential common stock equivalents are antidilutive (see Note 12).
	(i) Segment Reporting
	The Company views its operations and manages its business as one operating segment. Accordingly, the Company operates in one segment, which is the business of discovering and developing novel therapeutics that modulate immune responses through TLRs. As a result, the financial information disclosed herein represents all of the material financial information related to the Company’s principal operating segment. For all of the periods presented, all of the Company’s revenues were generated in the United States. As of December 31, 2013 and 2012, all assets were located in the United States.
	(j) Stock-Based Compensation
	The Company recognizes all share-based payments to employees and directors as expense in the statements of operations and comprehensive loss based on their fair values. The Company records compensation expense over an award’s requisite service period, or vesting period, based on the award’s fair value at the date of grant. The Company’s policy is to charge the fair value of stock options as an expense, adjusted for forfeitures, on a straight-line basis over the vesting period, which is generally four years for employees and three years for directors. Prior to December 2011, the vesting of all of the Company’s stock options was based on the passage of time and the employees’ continued service. In December 2011 and January 2012, the Company granted performance-based stock options to purchase 697,500 shares of common stock to employees. As of the grant date of such options, options to purchase 174,375 shares were to vest immediately upon the achievement of various performance conditions and options to purchase 523,125 shares were to vest over a three year service period upon the achievement of the same performance conditions. During 2012, three of the specified performance conditions were achieved. As a result, options to purchase 80,213 shares vested immediately, and options to purchase 240,640 shares began vesting over a three-year period in accordance with the terms of the performance-based options. As of June 30, 2013, the remaining performance-based options were forfeited as the remaining performance conditions had not been met by their deadlines. The Company recognizes expense over the implicit and explicit service periods for awards with performance conditions when the Company determines the achievement of the performance conditions to be probable.
	The Company recorded charges of $1,398,000, $2,096,000, and $2,725,000 for the years ended December 31, 2013, 2012 and 2011, respectively, for stock-based compensation expense attributable to share-based payments made to employees and directors.
	The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model. The following assumptions apply to the options to purchase 5,072,583, 187,500, and 1,671,000 shares of common stock granted to employees and directors during the years ended December 31, 2013, 2012 and 2011, respectively:


			2013				2012				2011
	Average risk free interest rate			1.3	%			0.8	%			1.4	%
	Expected dividend yield			—				—				—
	Expected lives (years)			5				5.6				6.3
	Expected volatility			67	%			62	%			64	%
	Weighted average grant date fair value of options granted during the period (per share)		$	0.89			$	0.51			$	0.75
	Weighted average exercise price of options granted during the period (per share)		$	1.55			$	0.92			$	1.26
	The expected lives of the options and the expected volatility are based on historical experience. All options granted during the three years ended December 31, 2013 were granted at exercise prices equal to the fair market value of the common stock on the dates of grant.
	The fair value of options that vested during 2013, 2012 and 2011 amounted to $1,429,000, $2,123,000 and $2,707,000, respectively. The intrinsic value of options exercised amounted to $150,000 during 2013. There were no option exercises in 2012 and 2011. As of December 31, 2013, there was $4,543,000 of unrecognized compensation cost related to nonvested stock-based compensation arrangements, which the Company expects to recognize over a weighted average period of 3.4 years.
	(k) Research and Development Expenses
	All research and development expenses, including amounts funded by research collaborations, are expensed as incurred. Research and development expenses are comprised of costs incurred in performing research and development activities, including drug development trials and studies, drug manufacturing, laboratory supplies, external research, payroll including stock-based compensation and overhead.
	(l) Concentration of Credit Risk
	Financial instruments that subject the Company to credit risk primarily consist of cash and cash equivalents and available-for-sale investments. The Company’s credit risk is managed by investing its cash and cash equivalents and marketable securities in highly rated money market instruments, certificates of deposit, corporate bonds, and debt securities. Due to these factors, no significant additional credit risk is believed by management to be inherent in the Company’s assets. As of December 31, 2013, all of the Company’s cash, cash equivalents and investments are held at one financial institution.
	(m) Fair Value of Assets and Liabilities
	The Company measures fair value at the price 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 using assumptions that market participants would use in pricing the asset or liability (the “inputs”) into a three-tier fair value hierarchy. This fair value hierarchy gives the highest priority (Level 1) to quoted prices in active markets for identical assets or liabilities and the lowest priority (Level 3) to unobservable inputs in which little or no market data exists, requiring companies to develop their own assumptions. Observable inputs that do not meet the criteria of Level 1, and include quoted prices for similar assets or liabilities in active markets or quoted prices for identical assets and liabilities in markets that are not active, are categorized as Level 2. Level 3 inputs are those that reflect the Company’s estimates about the assumptions market participants would use in pricing the asset or liability, based on the best information available in the circumstances. Valuation techniques for assets and liabilities measured using Level 3 inputs may include unobservable inputs such as projections, estimates and management’s interpretation of current market data. These unobservable Level 3 inputs are only utilized to the extent that observable inputs are not available or cost-effective to obtain. The Company applies ASU No. 2011-04, “Fair Value Measurement (Topic 820),” in its fair value measurements and disclosures.
	The table below presents the assets and liabilities measured and recorded in the financial statements at fair value on a recurring basis at December 31, 2013 and 2012 categorized by the level of inputs used in the valuation of each asset and liability.


	(In thousands)		Total				Quoted Prices				Significant				Significant
							in Active				Other				Unobservable
							Markets				Observable				Inputs
							for Identical				Inputs				(Level 3)
							Assets or				(Level 2)
Liabilities
(Level 1)
December 31, 2013
Assets
Money market funds		$	25,201			$	25,201			$	—			$	—
Short-term investments – commercial paper			1,997				—				1,997				—
Short-term investments – corporate bonds			1,128								1,128
Long-term investments			6,189				—				6,189				—

Total Assets		$	34,515			$	25,201			$	9,314			$	—

Total Liabilities		$	—			$	—			$	—			$	—

December 31, 2012
Assets
Money market funds		$	9,990			$	9,990			$	—			$	—

Total Assets		$	9,990			$	9,990			$	—			$	—

Total Liabilities		$	—			$	—			$	—			$	—


The Level 1 assets consist of money market funds, which are actively traded daily. The Level 2 assets consist of corporate bond and commercial paper investments whose fair value may not represent actual transactions of identical securities. The fair value of corporate bonds is generally determined from quoted market prices received from pricing services based upon quoted prices from active markets and/or other significant observable market transactions at fair value. The fair value of commercial paper is generally determined based on the relationship between the investment’s discount rate and the discount rates of the same issuer’s commercial paper available in the market which may not be actively traded daily. Since these fair values may not be based upon actual transactions of identical securities, they are classified as Level 2. Since any investments are classified as available-for-sale securities, any unrealized gains or losses are recorded in accumulated other comprehensive income or loss within stockholders’ equity on the balance sheet. The Company did not elect to measure any other financial assets or liabilities at fair value at December 31, 2013 or 2012.
In connection with the sale of its Series D preferred stock in November 2011, the Company issued warrants which contained provisions for anti-dilution protection in the event that the Company issued other equity securities at a price below $1.46 per common share. Because of the potential adjustment to the warrant exercise price that could result from this anti-dilution protection, the warrants did not meet the criteria set forth in ASC 815-40, “Derivatives and Hedging – Contracts in Entity’s own Stock” to be considered indexed to the Company’s own stock. Accordingly, the Company recorded the fair value of these warrants as a liability. The Company estimated the fair value of these warrants at the issuance date using the Black-Scholes Model as the result was not significantly different than the use of a lattice or binomial model because the price protection provision is subject to a floor of $1.46 per share and the initial exercise price is $1.63. The Company characterized this warrant liability as a Level 3 liability because its fair value measurement was based, in part, on significant inputs not observed in the market and reflects the Company’s assumptions as to the expected warrant exercise price, the expected volatility of the Company’s common stock, the expected dividend yield, the expected term of the warrant instrument and the expected percentage of warrants to be exercised.
The Company revalued the warrants at the end of each quarter using the Black-Scholes Model and recognized the change in the fair value of the warrants in the statements of operations and comprehensive loss as other income (expense). The following assumptions and other inputs were used to compute the fair value of the warrant liability as of the November 4, 2011 issuance date, December 31, 2011 and November 9, 2012 when it was transferred to stockholders’ equity, as explained below:


		November 4,				December 31,				November 9,
		2011				2011				2012
Common stock price		$	1.92			$	1.05			$	0.7
Expected warrant exercise price		$	1.46			$	1.46			$	1.46
Remaining term of warrant (years)			5				4.8				4
Expected volatility			61	%			58	%			59	%
Average risk free interest rate			0.9	%			0.8	%			0.5	%
Expected dividend yield			—				—				—
Expected percentage of warrants to be exercised			100	%			100	%			100	%
The closing price of the Company’s common stock is readily determinable since it is publicly traded. The exercise price of the warrant was initially set at $1.63 subject to adjustment to as low as the $1.46 minimum exercise price per share for diluting effects such as if in specified circumstances the Company sells its common stock at a price below $1.46 per share. The Company used the $1.46 minimum exercise price as an assumption in computing the fair value of the warrant at November 4, 2011 and December 31, 2011 because the Company’s common stock was trading below the $1.63 maximum exercise price as of such dates. The sale of shares of Series E preferred stock and Series E warrants in our November 2012 Series E financing triggered an anti-dilution adjustment under the terms of the Series D warrants, resulting in the exercise price of the Series D warrants being reduced and fixed at the minimum $1.46 per share and the Series D warrants no longer being subject to any anti-dilution adjustments. Since the exercise price of the Series D warrants became fixed, the Series D warrants then met the exception under ASC 815-40 as they were now “indexed to the company’s own stock” and met certain criteria for equity classification, thus the Series D warrants were marked to fair value through earnings as of November 9, 2012 and then reclassified to stockholders equity at that time. The estimated remaining term of the warrant is readily determinable from the warrant agreement as it is the remaining contractual term. The expected volatility is based on the actual stock-price volatility over a period equal to the greater of the remaining term of the warrant or three years. The assumed risk-free interest rate is based on the U.S. Treasury security rate with a term equal to the remaining term of the warrant. The assumed dividend yield of zero is based on the fact that the Company has never paid cash dividends to common stockholders and has no present intention to pay cash dividends to common stockholders. The Company assumed that future financings would dilute the warrant holder’s ownership in the Company such that the 19.99% ownership limitation would not prevent the warrant holder from exercising all of the warrants during the term of the warrants.
Changes in the warrant liability from November 4, 2011 to November 9, 2012 were as follows:


(In thousands)		Fair Value of
(In thousands)		Warrant Liability
Balance, November 4, 2011		$	3,152
Decrease in fair value			(1,974	)

Balance, December 31, 2011			1,178
Decrease in fair value			(675	)
Transfer to stockholders’ equity			(503	)

Balance, November 9, 2012		$	—

The fair value of the warrants decreased from $3,152,000 at November 4, 2011 to $1,178,000 at December 31, 2011 primarily due to decreases in the market price of the Company’s common stock resulting in the recognition of $1,974,000 in non-operating income in 2011. The fair value of the warrants decreased from $1,178,000 at December 31, 2011 to $503,000 at November 9, 2012 primarily due to decreases in the market price of the Company’s common stock and the remaining term of the warrants resulting in the recognition of $675,000 of non-operating income during the period ended November 9, 2012 at which time the $503,000 fair value of the warrant liability was transferred to stockholders’ equity.
The Company did not elect to measure any other financial assets or liabilities at fair value.

Investments

Investments	12 Months Ended
Investments	Dec. 31, 2013
Investments Debt And Equity Securities [Abstract]	'
Investments	'
	3. Investments
	The Company’s available-for-sale investments at fair value consisted of the following at December 31, 2013:


		December 31, 2013
		Cost		Gross			Gross		Estimated
				Unrealized			Unrealized		Fair
				(Losses)			Gains		Value
		(In thousands)
	Commercial paper due in one year or less	$	1,997	$	—		$	—	$	1,997
	Corporate bonds due in one year or less		1,128		—			—		1,128

	Total short-term investments		3,125		—			—		3,125
	Corporate bonds due in one year or more		6,196		(7	)		—		6,189

	Total long-term investments		6,196		(7	)		—		6,189

	Total investments	$	9,321	$	(7	)	$	—	$	9,314

	The Company had no investments at December 31, 2012. The Company had no realized gains or losses from available-for-sale securities in 2013, 2012 or 2011. There were no losses or other-than-temporary declines in value included in “Investment income, net” for any securities for the three years ended December 31, 2013. The Company had no auction rate securities as of December 31, 2013 and 2012. See Notes 2(f) and 2(m).

Property_and_Equipment

Property and Equipment	12 Months Ended
Property and Equipment	Dec. 31, 2013
Property Plant And Equipment [Abstract]	'
Property and Equipment	'
	4. Property and Equipment
	At December 31, 2013 and 2012, net property and equipment at cost consisted of the following:


		December 31,
		2013		2012
		(In thousands)
	Leasehold improvements	$	525	$	525
	Laboratory equipment and other		2,854		2,856

	Total property and equipment, at cost		3,379		3,381
	Less: Accumulated depreciation and amortization		3,289		3,163

	Property and equipment, net	$	90	$	218

	Depreciation and amortization expense was approximately $137,000, $251,000 and $494,000 in 2013, 2012 and 2011, respectively.

Accrued_Expenses

Accrued Expenses	12 Months Ended
Accrued Expenses	Dec. 31, 2013
Payables And Accruals [Abstract]	'
Accrued Expenses	'
	5. Accrued Expenses
	At December 31, 2013 and 2012, accrued expenses consisted of the following:


		December 31,
		2013		2012
		(In thousands)
	Payroll and related costs	$	817	$	199
	Clinical and nonclinical trial expenses		1,277		895
	Cost of regaining rights to cancer program		966		1,309
	Professional and consulting fees		337		344
	Other		109		255

		$	3,506	$	3,002

Collaboration_and_License_Agre

Collaboration and License Agreements	12 Months Ended
	Dec. 31, 2013
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'
Collaboration and License Agreements	'
	6. Collaboration and License Agreements
	(a) Collaboration and License Agreement with Merck & Co.
	In December 2006, the Company entered into an exclusive, worldwide license and research collaboration agreement with Merck & Co. to research, develop, and commercialize vaccine products containing the Company’s TLR7, TLR8, and TLR9 agonists in the fields of cancer, infectious diseases, and Alzheimer’s disease. Under the terms of the agreement, the Company granted Merck & Co. exclusive rights to a number of the Company’s TLR7, TLR8, and TLR9 agonists for use in combination with Merck & Co.’s therapeutic and prophylactic vaccines under development in the fields of cancer, infectious diseases, and Alzheimer’s disease. There is no limit under the agreement to the number of vaccines to which Merck & Co. can apply the Company’s agonists within these fields. The Company also agreed with Merck & Co. to engage in a two-year research collaboration to generate novel agonists targeting TLR7 and TLR8 incorporating both Merck & Co. and the Company’s chemistry for use in vaccines in the defined fields. Under the terms of the agreement, Merck & Co. extended the research collaboration for two additional years to December 2010. Under the terms of the agreement:

		•	Merck & Co. paid the Company a $20.0 million upfront license fee;

		•	Merck & Co. purchased $10.0 million of the Company’s common stock at $5.50 per share;

		•	Merck & Co. agreed to fund the research and development collaboration through its term;

		•	Merck & Co. agreed to pay the Company milestone payments as follows:

		•	up to $165.0 million if vaccines containing the Company’s TLR9 agonist compounds are successfully developed and marketed in each of the oncology, infectious disease, and Alzheimer’s disease fields;

		•	up to $260.0 million if vaccines containing the Company’s TLR9 agonist compounds are successfully developed and marketed for follow-on indications in the oncology field and if vaccines containing the Company’s TLR7 or TLR8 agonists are successfully developed and marketed in each of the oncology, infectious disease, and Alzheimer’s disease fields; and

		•	if Merck & Co. develops and commercializes additional vaccines using the Company’s agonists, the Company would be entitled to receive additional milestone payments; and

		•	Merck & Co. agreed to pay the Company mid to upper single-digit royalties on net product sales of vaccines using the Company’s TLR agonist technology that are developed and marketed, with the royalty rates being dependent on disease indication and the TLR agonist employed.

	The Company recognized the $20.0 million upfront payment as revenue over four years, including the initial two-year research term and the two-year extension period that ended in December 2010, which was the Company’s period of continuing involvement under the research collaboration. The Company has recognized a total of $1.0 million of milestone revenue under the license and collaboration agreement, which related to the achievement of a preclinical milestone with one of its TLR9 agonists used as an adjuvant in cancer vaccines.
	In December 2006, in connection with the execution of the license and collaboration agreement, the Company entered into a stock purchase agreement with Merck & Co. Pursuant to such stock purchase agreement, the Company issued and sold to Merck & Co. 1,818,182 shares of the Company’s common stock for a price of $5.50 per share resulting in aggregate gross proceeds of $10.0 million.
	(b) Collaboration and License Agreement with Merck KGaA
	In December 2007, the Company entered into an exclusive, worldwide license agreement with Merck KGaA to research, develop and commercialize products containing its TLR9 agonists, including IMO-2055, a TLR9 agonist that has shown evidence of clinical activity in multiple oncology trials (including renal cell cancer and non-small cell lung cancer), for the treatment of cancer, excluding cancer vaccines. Under the terms of the agreement: Merck KGaA paid the Company in February 2008 a $40.0 million upfront license fee in Euros of which $39.7 million was received due to foreign currency exchange rates in effect at that time, and Merck KGaA agreed to reimburse costs for the Company’s IMO-2055 clinical trials for the period in which the Company continued to conduct the trials on behalf of Merck KGaA. In February 2009, the agreement was amended so that the Company could initiate and conduct on behalf of Merck KGaA additional clinical trials of IMO-2055, and Merck KGaA agreed to reimburse the Company for costs associated with any additional trials that the Company initiated and conducted. As of March 2010, Merck KGaA assumed sponsorship of all ongoing clinical trials of IMO-2055 for the treatment of cancer, and responsibility for all further clinical development of IMO-2055 in the treatment of cancer, excluding vaccines.
	The Company recognized the $40.0 million upfront payment as revenue over the twenty-eight month term that ended in June 2010, which was the Company’s period of continuing involvement under the research collaboration. The Company has recognized a total of $12.1 million of milestone revenue related to the initiation of clinical trials of IMO-2055.
	In November 2011, the Company and Merck KGaA entered into a termination agreement terminating the license agreement. Under the termination agreement:

		•	the license agreement was terminated and the Company regained all rights for developing TLR9 agonists for the treatment of cancer, including all rights to IMO-2055 and any follow-on TLR9 agonists;

		•	Merck KGaA agreed to continue to conduct the Phase 2 trial of IMO-2055 in combination with cetuximab that was then ongoing and other specified related activities;

		•	Merck KGaA agreed to complete and analyze all clinical trials that Merck KGaA had initiated or for which Merck KGaA had assumed sponsorship and to finalize clinical study reports;

		•	the Company gained rights to the data from the Phase 2 trial of IMO-2055 in combination with cetuximab, as well as to the data from the Phase 1 trials conducted in other cancer indications;

		•	the Company agreed to reimburse Merck KGaA a maximum of €1.8 million ($2.5 million using a December 31, 2013 exchange rate) of Merck KGaA’s costs for the third-party contract research organization that is coordinating the Phase 2 trial of IMO-2055 in combination with cetuximab, payable in eleven installments comprised of ten monthly installments to be invoiced by Merck KGaA to the Company commencing on March 1, 2012 and a final payment payable by the Company to Merck KGaA upon Merck KGaA’s completion of certain specified activities. As of December 31, 2013, the Company has paid €1.1 of the €1.8 million ($1.4 million (using exchange rates in effect at the time that the payments were made) of the $2.5 million);

		•	the Company agreed to pay to Merck KGaA one-time €1.0 million ($1.4 million using a December 31, 2013 exchange rate) milestone payments upon occurrence of each of the following milestones: (i) partnering of IMO-2055 between the Company and any third party, (ii) initiation of any Phase 2 or Phase 3 clinical trial for IMO-2055 and (iii) regulatory submission of IMO-2055 in any country; and

		•	Merck KGaA granted the Company an option to obtain a license to certain manufacturing and formulation know-how owned or developed by Merck KGaA under the License Agreement and to Merck KGaA’s IMOxine trademark. The Company’s option to license the IMOxine trademark has expired. If the Company elects to exercise its option with respect to the manufacturing and formulation know-how, the Company has agreed to pay a low single digit royalty on net sales of IMO-2055, with respect to such license.
	The Company recorded the €1.8 million ($2.4 million using a November 30, 2011 exchange rate) that it has agreed to reimburse Merck KGaA in installment payments as research and development expense for the fourth quarter of 2011 as such amount represented the cost of regaining the Company’s rights to IMO-2055 and follow-on compounds for use in the treatment of cancer, excluding cancer vaccines. As of December 31, 2013, €0.7 million ($1.0 million using a December 31, 2013 exchange rate) of these installments remained payable under the termination agreement and is recorded under accrued expenses in the condensed balance sheet.
	(c) Other License Agreements
	The Company has out-licensed and in-licensed therapies related to antisense technology.
	Out-licenses. In 2001, the Company entered into an agreement with Isis Pharmaceuticals, Inc. (“Isis”), under which it granted Isis a license, with the right to sublicense, to its antisense chemistry and delivery patents and patent applications; and it retained the right to use these patents and applications in its own drug discovery and development efforts and in collaborations with third parties. During 2001, Isis paid the Company $15.0 million in cash and issued 857,143 shares of its common stock having an aggregate fair market value on the dates on which title to the shares was received of $17.3 million and is required to pay the Company a low to mid double-digit percentage of specified sublicense income it receives from some types of sublicenses of its patents and patent applications. As of December 31, 2013, the Company has received $0.3 million in sublicense income from Isis. Also under the agreement, the Company licensed from Isis specified antisense patents and patent applications, principally Isis’ suite of RNase H patents and patent applications. The Company also paid to Isis $0.7 million and issued 1,005,499 shares of common stock having a fair market value of approximately $1.2 million on the date of issuance for this license and is obligated to pay Isis an annual maintenance fee and low single-digit royalties on net sales of antisense products sold that are covered by Isis’s patent rights. The Company has the right to use these patents and patent applications in its drug discovery and development efforts and in some types of third-party collaborations. As of December 31, 2013, the Company has only paid Isis annual maintenance fees and has not paid any royalties. The agreement may be terminated for an uncured material breach by either party. The licenses granted under the Isis agreement terminate upon the last to expire of the patents and patent applications licensed under the agreement. The Company may terminate at any time the sublicense by Isis to it of the patents and patent applications.
	In addition, the Company is a party to two other license agreements involving the license of its antisense patents and patent applications for oligonucleotide chemistry and delivery and for specific gene targets, under which the Company typically is entitled to receive license fees, sublicensing income, research payments, payments upon achievement of developmental milestones, and royalties on product sales. As of December 31, 2013, we had received a total of $1.5 million under these agreements.
	In-licenses. The Company’s principal in-license related to antisense technology is with University of Massachusetts Medical Center for antisense chemistry and for certain gene targets. Under the terms of the license agreement with University of Massachusetts Medical Center, the Company is the worldwide, exclusive licensee under a number of U.S. issued patents and various patent applications owned by University of Massachusetts Medical Center relating to the chemistry of antisense oligonucleotides and their use. Many of these patents and patent applications have corresponding applications on file or corresponding patents in other major industrial countries. The patents licensed to the Company by University of Massachusetts Medical Center expire in 2014. This license expires upon the expiration of the last to expire of the patents covered by the license. Under the agreement, the Company has agreed to pay a low single-digit royalty on net product sales, a low double-digit percentage of any sublicense license income received, and a small annual license maintenance fee. Since 1999, the Company has paid approximately $1.8 million to University of Massachusetts Medical Center under this license agreement.
	Additionally, the Company has entered into five other royalty-bearing license agreements under which it has acquired rights to antisense related patents, patent applications, and technology. Under all of these in-licenses, the Company is obligated to pay low to mid single-digit royalties on its net sales of products or processes covered by a valid claim of a licensed patent or patent application. Under some of these in-licenses, the Company is required to pay a low double-digit specified percentage of any sublicense income, and all of these in-licenses impose various commercialization, sublicensing, insurance, and other obligations on us, and its failure to comply with these requirements could result in termination of the in-licenses.

Series_D_Redeemable_Convertibl

Series D Redeemable Convertible Preferred Stock and Warrants	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Series D Redeemable Convertible Preferred Stock and Warrants	'
	7. Series D Redeemable Convertible Preferred Stock and Warrants
	The following securities were issued in connection with the Company’s November 4, 2011 financing discussed in Note 15.
	(a) Redeemable Convertible Preferred Stock
	The Series D preferred stock has the rights and preferences set forth in the Certificate of Designations, Preferences and Rights of Series D preferred stock of the Company, as amended (the “Series D Certificate of Designations”), as summarized below.

		•		Dividends — The holders of the Series D preferred stock are entitled to receive dividends payable quarterly in arrears at the rate of 7% per annum. Such dividends were required to be paid in cash through September 30, 2013 and thereafter may be paid in cash or with shares of common stock or with shares of a to-be-created new series of non-voting preferred stock in the event that payment of such dividends may not be made in shares of its common stock as a result of the application of the beneficial ownership and voting power limitations set forth the Series D Certificate of Designations, as determined by the Company in its sole discretion, except that the Company may not pay any dividends to a holder of Series D preferred stock in shares of common stock to the extent the issuance of such shares would result in the holder of Series D preferred stock and its affiliates beneficially owning more than 19.99% of (i) the common stock outstanding or (ii) the combined voting power of the securities of the Company outstanding immediately after giving effect to the issuance of such shares of common. Dividends payable on the Series D preferred stock amounted to $160,000 and $190,000 at December 31, 2013 and 2012, respectively. Under the original terms of the Series D preferred stock, the 4.6% dividends that the Company originally paid to the Series E preferred stockholders under the terms of the Series E preferred stock were also be paid to the Series D preferred stockholders on an as-converted to common stock basis, which resulted in Series D preferred stockholders being entitled to an additional 2.2% per annum cash dividend payable quarterly in arrears. At the Company’s 2013 annual meeting of stockholders (the “2013 Annual Meeting”), an amendment to the Series D Certificate of Designations to, among other things, modify the terms of the Series D preferred stock requiring payment of dividends to Series D preferred stockholders upon payment of dividends to Series E stockholders was approved by the Company’s stockholders. As a result, the Series E preferred stockholders became entitled to receive dividends payable in cash quarterly in arrears at the rate of 8% per annum and the Series D preferred stockholders ceased to be entitled to corresponding dividends effective July 26, 2013.

		•		Liquidation and Other Events — In the event of a liquidation, dissolution or winding up of the Company (a “Liquidation”), whether voluntary or involuntary, after payment or provision for payment of debts and other liabilities of the Company, the holders of the Series D preferred stock then outstanding shall be entitled to be paid out of the assets of the Company available for distribution to its stockholders an amount per share of Series D preferred stock equal to the amount that would be payable with respect to such share had all shares of Series D preferred stock been converted into shares of common stock immediately prior to such Liquidation and not any amount greater than that amount in preference to the Company’s common stock. Such amount will be paid before any cash distribution may be made or any other assets distributed in respect of junior securities to the holders of any junior securities including, without limitation, common stock and Series A preferred stock of the Company. In the event of a sale of the corporation, after payment to the holders of the Series A preferred stock and any other class of capital stock of the Company ranking senior to the Series D preferred stock, the remaining assets of the Company available for distribution to its stockholders will be distributed among the holders of shares of Series E preferred stock, Series D preferred stock and common stock on a pro rata (and as converted to common stock) basis based on the number of shares held by each such holder.

		•		Conversion — Each share of Series D preferred stock is convertible, at the option of the holder thereof, at any time and from time to time, and without the payment of additional consideration by the holder thereof, into such number of fully paid and nonassessable shares of common stock as is determined by dividing the Series D preferred stock original issue price by the Series D preferred stock conversion price in effect at the time of conversion. The Series D preferred stock conversion price was initially equal to $1.63 and the Series D preferred stock issue price was initially equal to the $8.1375 original purchase price of the Series D preferred stock. Accordingly, each share of Series D preferred stock was initially convertible at the option of the holder into five fully paid and nonassessable shares of the common stock. As a result of the Company’s Series E financing in November 2012, the Series D preferred stock conversion price was adjusted to the $1.46 per share minimum resulting in each share of Series D preferred stock becoming convertible at the option of the holder into 5.5736 fully paid and nonassessable shares of the common stock. No holder may convert its shares to the extent such conversion would result in the holder and its affiliates beneficially owning more than 19.99% of the common stock outstanding. The Series D preferred stock conversion price, and the rate at which shares of Series D preferred stock may be converted into shares of common stock, may be subject to adjustment for stock dividends, stock splits and other events, as provided in the Series D Certificate of Designations.

		•		Redemption by Company — After November 4, 2013 and following notice the Company may redeem, for cash payment equal to the original Series D preferred stock issue price per share plus any accrued or declared but unpaid dividends thereon, all or a portion of the Series D preferred stock if the closing price of the common stock for 20 or more trading days in a period of 30 consecutive trading days is greater than or equal to 200% of the Series D preferred stock conversion price.

	As of December 31, 2013 there were 1,124,260 shares of Series D preferred stock designated, issued and outstanding.
	At the time of its issuance and prior to being amended, the Series D preferred stock was first assessed under ASC 480, “Distinguishing Liabilities from Equity” and it was determined that it was not within the scope of ASC 480 so the preferred stock was not considered a liability under ASC 480. The preferred stock was then assessed under ASC 815, “Derivatives and Hedging.”
	The Series D preferred stock contained three embedded features: (1) optional redemption by the Company; (2) optional redemption by the holders; and (3) optional conversion by the holders. Each embedded feature met the definition of a derivative. The Company believed that the Series D preferred stock was an equity host for the purposes of assessing the embedded derivatives for potential bifurcation. The Company noted the following regarding these embedded features:

		a.	Optional Redemption by the Company and Optional Redemption by the Holders — the redemption features were assessed under ASC 815-40 to determine if they were eligible for the exemption from derivative accounting. In order to meet the exemption the feature must be “indexed to the company’s own stock” and meet specified criteria for equity classification. Both redemption features met these requirements and were not bifurcated, or accounted for separately from the preferred stock.

		b.	Optional Conversion by the Holder — the optional conversion by the holder feature was determined to be clearly and closely related to the preferred stock host. As such the conversion feature did not require bifurcation under ASC 815.
	The Series D preferred stock was then assessed under ASC 470, “Debt,” to determine if there was a beneficial conversion feature (“BCF”). The BCF compares the carrying value of the preferred stock after the value of any derivatives has been allocated from the proceeds (in this case, the Warrant Liability) to the transaction date value of number of shares that the holder can convert into. The calculation resulted in a BCF of $4,445,000. The BCF was recorded in additional paid-in capital.
	The following is a summary of the changes in the Series D preferred stock during 2012 and 2011 (in thousands):


	Gross proceeds from November 4, 2011 Series D financing (including $351 paid for the warrants)		$	9,500
	Less — allocation of proceeds to:
	fair value of warrants			(3,152	)
	beneficial conversion feature			(4,445	)
	transaction costs			(427	)

	Net proceeds allocated to Series D preferred stock			1,476
	Accretion of beneficial conversion feature			4,445

	Fair value of Series D preferred stock — November 4, 2011		$	5,921

	Fair value of Series D preferred stock — December 31, 2011		$	5,921
	Beneficial conversion feature related to Series E financing			(1,238	)
	Accretion of beneficial conversion feature			1,238

	Fair value of Series D preferred stock — December 31, 2012		$	5,921


	The effects of the extinguishment of the Series D preferred stock during 2013 are discussed in Note 14.
	Because the Series D preferred stock was redeemable upon events outside the control of the Company, the Company initially recorded it in temporary equity. The initial carrying value of the Series D preferred stock was $1,476,000, after discounts for the proceeds allocated to the warrant liability and the BCF, and the recording of the transaction costs. The conversion option of the Series D preferred stock was immediately exercisable. As a result, the $4,445,000 discount related to the BCF was immediately accreted to preferred dividends, resulting in an increase in the carrying value of the Series D preferred stock to $5,921,000 at November 4, 2011. The sale of shares and warrants in our November 2012 Series E financing triggered an anti-dilution adjustment under the terms of the Series D preferred stock, resulting in the conversion price of the Series D preferred stock being reduced and fixed at the minimum $1.46 per share and the Series D preferred stock no longer being subject to any anti-dilution adjustments which resulted in an additional $1,238,000 discount related to the additional BCF. The additional BCF was immediately accreted to preferred dividends in 2012 which resulted in the carrying value of the Series D preferred stock remaining at $5,921,000. The Series D preferred stock was redeemable by the holder for the original $9,149,000 purchase price plus unpaid accrued dividends upon a fundamental change, as described above. The Company has determined that the occurrence of a fundamental change was not probable and did not accrete the difference between the $5,921,000 fair value of the Series D preferred stock and the redemption value of $9,149,000 purchase price plus unpaid accrued dividends. If the occurrence of a fundamental change became probable, the Company would have accreted this $3,228,000 difference at that time.
	The Series D Convertible Preferred Stock and Warrant Purchase Agreement was amended in connection with the Series E financing. The amendments consisted of changes to voting rights limitations and restrictions on the transferability of securities issued in the November 2011 Series D financing. There is no specific guidance on accounting for amendments to preferred stock agreements. However it is generally accepted that such changes should be analyzed to determine if they represent a modification or an extinguishment of the preferred stock. The Company has adopted a qualitative approach to assessing whether amendments are accounted for as modifications or extinguishments. The Company considers the nature of the changes to the preferred stock agreement, including whether the amendments significantly change a substantial contractual term or fundamentally change the nature of the stock; and whether the amendment of the terms would have changed the initial accounting for the stock. If the amendments significantly change a substantial term; fundamentally change the nature of the preferred shares; or change the accounting for the stock, then the change is accounted for as an extinguishment. Otherwise the amendments are accounted for as modifications.
	The Company has considered the nature of these amendments and whether the amendments significantly change any substantial terms that affect the initial accounting for the Series D preferred stock. The Company determined that these Series D amendments related to the November 2012 Series E financing were not to substantial terms of the agreement and did not fundamentally change the nature of the Series D preferred stock. In addition, the Company assessed the original accounting for the Series D preferred stock and determined that the accounting did not change as a result of the amendments. Thus, the changes were considered a modification and not an extinguishment. The Company then considered the appropriate model for accounting for the modification of the Series D preferred stock. The Company considered the debt and the share based payment modification guidance and determined that the share based modification rules included in ASC 718-20-35 were more appropriate. The model under ASC 718-20-35 requires the measurement of the fair value of the Series D preferred stock immediately before and after the modification. The Company determined that the change in fair value resulting from the modification was de minimis, as the Series D amendments related to the Series E financing did not affect substantial terms of the agreement and did not affect the Company’s financial statements.

	(b) Warrants
	The Series D warrants had an initial exercise price of $1.63 per common share (subject to adjustment as provided therein) and may be exercised at the holder’s option at any time on or before November 4, 2016. The sale of shares of Series E preferred stock and Series E warrants in the Company’s November 2012 Series E financing triggered an anti-dilution adjustment under the terms of the Series D warrants, resulting in the conversion price of the Series D warrants being reduced and fixed at the minimum $1.46 per share and the Series D warrants no longer being subject to any anti-dilution adjustments. The Series D warrants provide that the Company shall not effect any exercise of the Series D warrants, and the Series D warrants may not be exercised with respect to any portion of the Series D warrants, to the extent that such exercise would result in the holder and its affiliates beneficially owning more than 19.99% of (i) the number of shares of common stock outstanding or (ii) the combined voting power of the securities of the Company outstanding immediately after giving effect to the issuance of shares of Common Stock issuable upon exercise of the Series D warrants. After November 4, 2013, the Company may redeem the Series D warrants for $0.01 per share of common stock issuable on exercise of the Series D warrants following notice to the holder if the closing price of the common stock for 20 or more trading days in a period of 30 consecutive trading days is greater than or equal to $6.51 (subject to adjustment for stock splits, stock dividends, combinations, recapitalizations, reclassifications, and similar transactions affecting the common stock).
	The Series D warrants were first assessed under ASC 480 and it was determined that they were not within its scope so the warrants were not considered a liability under ASC 480. The Series D warrants were then assessed under ASC 815 and were determined to be derivative instruments since the price protection features do not meet the “indexed to the company’s own stock” exemption requirements in ASC 815-40. The Series D warrants were recorded at fair value as of the transaction date and were being marked to fair value through earnings each quarter. The sale of shares of Series E preferred stock and Series E warrants in the Company’s November 2012 Series E financing triggered an anti-dilution adjustment under the terms of the Series D warrants, resulting in the exercise price of the Series D warrants being reduced and fixed at the minimum $1.46 per share and the Series D warrants no longer being subject to any anti-dilution adjustments. Since the exercise price of the Series D warrants became fixed, the Series D warrants then met the exception under ASC 815-40 as they were now “indexed to the company’s own stock” and met certain criteria for equity classification. Accordingly, the Series D warrants were marked to fair value through earnings as of November 9, 2012 and the remaining $503,000 was reclassified to stockholders equity at that time. See Note 2(m).
	The Series D warrants were also amended in connection with the November 2012 Series E financing. The amendments consisted of changes in limitations on the Company’s right to redeem the Series D warrants and the Series D warrant holder’s right to exercise the Series D warrants. There is no specific guidance on accounting for amendments to warrant agreements. However it is generally accepted that such changes should be analyzed to determine if they represent a modification or an extinguishment of the warrant. The Company has adopted a qualitative approach to assessing whether amendments are accounted for as modifications or extinguishments. The Company considers the nature of the changes to the warrant agreement, including whether the amendments significantly change a substantial contractual term or fundamentally change the nature of the warrant; and whether the amendment of the terms would have changed the initial accounting for the Series D warrant. If the amendments significantly change a substantial term; fundamentally change the nature of the Series D warrant; or change the accounting for the Series D warrant, then the change is accounted for as an extinguishment. Otherwise the amendments are accounted for as modifications.
	The Company has considered the nature of these amendments and whether the amendments significantly change any substantial terms that affect the initial accounting for the Series D warrants. The Company determined that these amendments were not to substantial terms of the agreement and did not fundamentally change the nature of the Series D warrants. In addition, the Company assessed the original accounting for the Series D warrants and determined that the accounting did not change as a result of the amendments. Thus, the changes were considered a modification and not an extinguishment.
	The Company then considered the appropriate model for accounting for the modification of the Series D warrants. The Company considered the debt and the share based payment modification guidance and determined that the share based modification rules included in ASC 718-20-35 were more appropriate. The model under ASC 718-20-35 requires the measurement of the fair value of the Series D warrants immediately before and after the modification. The Company determined that the change in fair value resulting from the modification was de minimis, as the amendments did not affect substantial terms of the agreement and did not affect the Company’s financial statements.

Nonredeemable_Preferred_Stock_

Non-redeemable Preferred Stock, Common Stock and Other Stockholders' Equity	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Non-redeemable Preferred Stock, Common Stock and Other Stockholders' Equity	'
	8. Non-redeemable Preferred Stock, Common Stock and Other Stockholders’ Equity
	(a) Common Stock
	Pursuant to the terms of a unit purchase agreement dated as of May 5, 1998, the Company issued and sold a total of 1,199,684 shares of common stock (the “Put Shares”) at a price of $16.00 per share. Under the terms of the unit purchase agreement, the initial purchasers (the “Put Holders”) of the Put Shares have the right (the “Put Right”) to require the Company to repurchase the Put Shares. The Put Right may not be exercised by any Put Holder unless: (1) the Company liquidates, dissolves or winds up its affairs pursuant to applicable bankruptcy law, whether voluntarily or involuntarily; (2) all of the Company’s indebtedness and obligations, including without limitation the indebtedness under the Company’s then outstanding notes, has been paid in full; and (3) all rights of the holders of any series or class of capital stock ranking prior and senior to the common stock with respect to liquidation, including without limitation the Series A convertible preferred stock, have been satisfied in full. The Company may terminate the Put Right upon written notice to the Put Holders if the closing sales price of its common stock exceeds $32.00 per share for the twenty consecutive trading days prior to the date of notice of termination. Because the Put Right is not transferable, in the event that a Put Holder has transferred Put Shares since May 5, 1998, the Put Right with respect to those shares has terminated. As a consequence of the Put Right, in the event the Company is liquidated, holders of shares of common stock that do not have Put Rights with respect to such shares may receive smaller distributions per share upon the liquidation than if there were no Put Rights outstanding.
	As of December 31, 2013, the Company has repurchased or received documentation of the transfer of 399,950 Put Shares and 35,780 of the Put Shares continued to be held in the name of Put Holders. The Company cannot determine at this time what portion of the Put Rights of the remaining 763,954 Put Shares have terminated.

	(b) Warrants
	The Company has the following warrants outstanding and exercisable for the purchase of common stock at December 31, 2013:


	Expiration Date		Shares			Weighted
						Average Exercise
						Price Per share
	June 1, 2014			1,000,000		$	0.79
	August 5, 2015			1,628,402			3.71
	November 4, 2016			2,810,650			1.46
	November 9, 2017			8,484,840			0.7
	May 7, 2018			27,156,327			0.48
	May 7, 2020			15,816,327			0.01
	September 30, 2020			4,175,975			0.01

	Total			61,072,521			0.49

	See Note 7(b).
	(c) Stock Options
	Under the Company’s 2013 Stock Incentive Plan (the “2013 Stock Incentive Plan”), the Company may grant options to purchase common stock, stock appreciation rights, restricted stock awards and other forms of stock-based compensation. Stock options generally vest over three to four years, and expire no later than 10 years from the date of grant. A total of 4,000,000 shares of common stock, plus such additional number of shares of common stock (up to 5,945,000) as is equal to the sum of (i) the number of shares of common stock reserved for issuance under the Company’s 2008 Stock Incentive Plan (the “2008 Stock Incentive Plan”) that are available for grant under the 2008 Stock Incentive Plan immediately prior to the date the 2013 Stock Incentive Plan is approved by its stockholders and (ii) the number of shares of common stock subject to awards granted under the 2008 Stock Incentive Plan which awards expire, terminate or are otherwise surrendered, cancelled, or forfeited or repurchased by us at their original issuance price pursuant to a contractual repurchase right (subject, however, in the case of incentive stock options to any limitations of the Internal Revenue Code of 1986, as amended, (the “Code”)), may be issued pursuant to awards granted under the 2013 Stock Incentive Plan subject to reduction in the event that there are any “full-value awards,” as defined in the plan. The maximum number of shares of common stock with respect to which awards may be granted to any participant under the plan is 1,500,000 per calendar year. The compensation committee of the board of directors has the authority to select the employees to whom options are granted and determine the terms of each option, including (i) the number of shares of common stock subject to the option; (ii) when the option becomes exercisable; (iii) the option exercise price, which must be at least 100% of the fair market value of the common stock as of the date of grant; and (iv) the duration of the option, which may not exceed 10 years. Stock options may not be re-priced without shareholder approval. Discretionary awards to non-employee directors are granted and administered by a committee comprised of independent directors. As of December 31, 2013, options to purchase a total of 2,902,500 shares of common stock were outstanding under the 2013 Stock Incentive Plan. As of December 31, 2013, 1,317,099 shares of common stock remain available for grant under the 2013 Stock Incentive Plan.
	The Company is no longer granting stock options or other awards pursuant to the share-based compensation plans that were utilized prior to the approval of the 2013 Stock Incentive Plan. Under these earlier plans, stock options generally vested over three to four years and expired no later than 10 years from the date of grant. As of December 31, 2013, options to purchase a total of 7,245,719 shares of common stock were outstanding under these earlier plans.
	The following table summarizes information related to the outstanding and exercisable options during 2013 (in thousands, except per share amounts and years):


			Stock			Weighted-Average		Weighted-Average		Aggregate
			Options			Exercise Price		Remaining		Intrinsic
								Contractual Life		Value
								(in years)
	Outstanding at December 31, 2012			5,656		$	4.96
	Granted			5,073			1.55
	Exercised			(171	)		1.16
	Forfeited			(189	)		1.16
	Expired			(221	)		5.24

	Outstanding at December 31, 2013			10,148			3.38		7.54	$	21,233

	Exercisable at December 31, 2013			4,530			5.64		5.18		3,982
	Total exercisable or expected to vest			9,850			3.44		7.48		20,319

	(d) Employee Stock Purchase Plan
	The Company’s 1995 Employee Stock Purchase Plan (the “Stock Purchase Plan”), as amended, provides for the issuance of up to 500,000 shares of common stock to participating employees of the Company or its subsidiaries. Participation is limited to employees that would not own 5% or more of the total combined voting power or value of the stock of the Company after the grant.
	Under the Stock Purchase Plan, on the first day of a designated payroll deduction period, the “Offering Period,” the Company will grant to each eligible employee who has elected to participate in the Stock Purchase Plan an option to purchase shares of common stock as follows: the employee may authorize an amount, a whole percentage from 1% to 10% of such employee’s regular pay, to be deducted by the Company from such pay during the Offering Period. On the last day of the Offering Period, the employee is deemed to have exercised the option, at the option exercise price, to the extent of accumulated payroll deductions. Under the terms of the Stock Purchase Plan, the option price is an amount equal to 85% of the fair market value per share of the common stock on either the first day or the last day of the Offering Period, whichever is lower. In no event may an employee purchase in any one Offering Period a number of shares that is more than 15% of the employee’s annualized base pay divided by 85% of the market value of a share of common stock on the commencement date of the Offering Period. The Compensation Committee may, in its discretion, choose an Offering Period of 12 months or less for each of the Offerings and choose a different Offering Period for each Offering.
	Offering periods are three months in duration and commence on March 1, June 1, September 1, and December 1. In 2013, 2012, and 2011, the Company issued 14,716, 4,746, and 26,155 shares of common stock, respectively, under the Stock Purchase Plan.
	(e) Preferred Stock
	The Restated Certificate of Incorporation of the Company permits its board of directors to issue up to 5,000,000 shares of preferred stock, par value $0.01 per share, in one or more series, to designate the number of shares constituting such series, and fix by resolution, the powers, privileges, preferences and relative, optional or special rights thereof, including liquidation preferences and dividends, and conversion and redemption rights of each such series. The Company has designated 1,500,000 shares as Series A convertible preferred stock, 1,124,260 shares of Series D preferred stock (see Note 7) and 424,242 shares of Series E preferred stock (see Note 8(g)).
	(f) Series A Convertible Preferred Stock
	The dividends on the Series A convertible preferred stock are payable semi-annually in arrears at the rate of 1% per annum, at the election of the Company, either in cash or additional duly designated, fully paid and nonassessable shares of Series A preferred stock. The Company paid dividends in stock until 2004 when it elected to pay further dividends in cash. In the event of liquidation, dissolution or winding up of the Company, after payment of debts and other liabilities of the Company, the holders of the Series A convertible preferred stock then outstanding will be entitled to a distribution of $1 per share out of any assets available to shareholders. The Series A preferred stock is non-voting. All remaining shares of Series A preferred stock rank as to payment upon the occurrence of any liquidation event senior to the common stock. Shares of Series A preferred stock are convertible, in whole or in part, at the option of the holder into fully paid and nonassessable shares of common stock at $34.00 per share, subject to adjustment. As of December 31, 2013 and 2012, there were 655 shares of Series A convertible preferred stock outstanding.
	(g) Series E Convertible Preferred Stock
	The Series E convertible preferred stock was issued in connection with the Company’s November 9, 2012 financing discussed in Note 15. On November 9, 2012, the board of directors of the Company designated 424,242 shares as Series E preferred stock, having the rights and preferences set forth in the Certificate of Designations, Preferences and Rights of Series E Preferred Stock (the “Series E Certificate of Designations”). As of December 31, 2013 and 2012, there were 424,242 shares of Series E preferred stock outstanding. The rights and preferences of Series E preferred stock of the Company set forth in the Series E Certificate of Designations, as amended, are summarized below.

		•		Dividends — The holders of Series E preferred stock are entitled to receive cash dividends payable quarterly in arrears at the Initial Dividend Rate (as defined below) with the first payment date being March 31, 2013. The Company proposed at the 2013 Annual Meeting an amendment to the Series D Certificate of Designations to, among other things, modify the terms of the Series D preferred stock that require payment of dividends to Series D preferred stockholders upon payment of dividends to Series E stockholders. Since the stockholders of the Company approved the amendment to the Series D Certificate of Designations, the dividend rate with respect to the Series E preferred dividends increased from the Initial Dividend Rate to the rate of 8% per annum. The term “Initial Dividend Rate” means 4.6% per annum or such other percentage per annum as may be approved by the Company and by the holders of at least a majority of the then outstanding shares of Series E preferred stock. Dividends payable on the Series E preferred stock amounted to $119,000 and $40,000 at December 31, 2013 and 2012, respectively.

		•		Liquidation and Other Events — In the event of a liquidation, dissolution or winding up of the Company (other than a Sale of the Corporation as defined in the Series E Certificate of Designations) (a “Liquidation”), whether voluntary or involuntary, after payment or provision for payment of debts and other liabilities of the Company, the holders of the Series E preferred stock then outstanding will be entitled to be paid out of the assets of the Company available for distribution to its stockholders an amount per share of Series E preferred stock equal to the amount that would be payable with respect to such share had all shares of Series E preferred stock been converted into shares of common stock immediately prior to such Liquidation and not any amount greater than that amount in preference to the Company’s common stock. Such amount will be paid before any cash distribution may be made or any other assets distributed in respect of the holders of common stock, Series A convertible preferred stock, Series D preferred stock or any other class of capital stock of the Company ranking junior to the Series E preferred stock as to liquidation. In the event of a sale of the corporation, after payment to the holders of the Series A preferred stock and any other class of capital stock of the Company ranking senior to the Series E preferred stock, the remaining assets of the Company available for distribution to its stockholders will be distributed among the holders of shares of Series E preferred stock, Series D preferred stock and common stock on a pro rata (and as converted to common stock) basis based on the number of shares held by each such holder.

		•		Voting — The Series E preferred stock has no voting rights.

		•		Protective Provisions — For so long as at least 84,849 shares of Series E preferred stock, subject to adjustment, remain outstanding, the Company has agreed that it will not, directly or indirectly, (a) amend the Certificate of Incorporation or bylaws of the Company in a manner that adversely and uniquely affects the Series E preferred stock, (b) except as expressly permitted by the Series E Certificate of Designations, purchase or redeem or pay or declare any dividend or make any distribution on, any shares of capital stock of the Company, or (c) recapitalize or reclassify any of the common stock, without in each case the written consent or affirmative vote of the holders of at least 51% of the then outstanding shares of Series E preferred stock.

	•		Conversion — Each share of Series E preferred stock is convertible, at the option of the holder thereof, at any time and from time to time, and without the payment of additional consideration by the holder thereof, into such number of fully paid and nonassessable shares of common stock as is determined by dividing the Series E preferred stock original issue price by the Series E preferred stock conversion price in effect at the time of conversion. The Series E preferred stock conversion price is initially equal to $0.70 and the Series E preferred stock issue price is initially equal to the $14.00 original purchase price of the Series E preferred stock. Accordingly, each share of Series E preferred stock is initially convertible at the option of the holder into 20 fully paid and nonassessable shares of the common stock. No holder may convert its shares to the extent such conversion would result in the holder and its affiliates beneficially owning more than 19.99% of the outstanding common stock or outstanding voting power of the Company (including shares of common stock issuable upon conversion of the Series E preferred stock). The initial Series E preferred stock conversion price, and the rate at which shares of Series E preferred stock may be converted into shares of common stock, are subject to adjustment for stock dividends, stock splits and other similar events, as provided in the Series E Certificate of Designations.

	•		Redemption by Company — After the later of November 9, 2014 and the date that no shares of Series D preferred stock remain outstanding, the Company may redeem all or a portion of the Series E preferred stock for a cash payment equal to the original Series E preferred stock issue price per share plus any accrued or declared but unpaid dividends thereon following notice to the holders of the Series E preferred stock if the closing price of the common stock for 20 or more trading days in a period of 30 consecutive trading days is greater than or equal to 400% of the Series E preferred stock conversion price. The Company may not redeem any shares of Series E preferred stock from a holder that cannot convert such shares of Series E preferred stock into common stock as a result of the beneficial ownership limitations described above under “Conversion.” In such event, the Company may redeem such nonredeemable shares pursuant to alternative redemption provisions set forth in the Series E Certificate of Designations following notice to the holders of the nonredeemable shares, for a cash payment equal to the greater of the 20 consecutive trading day average closing price per share of the common stock ending on the trading day immediately prior to redemption date plus any dividends accrued or declared but unpaid thereon and the Series E conversion price plus any dividends accrued or declared but unpaid thereon.

The Series E preferred stock was first considered under ASC 480 and it was determined that it was not mandatorily redeemable. The Company identified the following three embedded features within the Series E preferred stock: (1) optional conversion by the holder; (2) optional redemption by the company; and (3) an alternative redemption by the company. The Series E preferred stock was determined to be an equity host. The optional conversion by the holder was assessed to be clearly and closely related to the Series E preferred stock and thus not subject to bifurcation under ASC 815. The optional redemption by the company and the alternative redemption by the company were both indexed to the Company’s own stock and met the criteria for equity classification under ASC 815-40 and thus were not required to be bifurcated. The Series E preferred stock is redeemable only at the Company’s option. In addition, the Series E preferred stock only has preferences in the event of a final liquidation or termination of the Company. In the event of a deemed liquidation, the Series E preferred stock has no preferences and ranks together with the common stockholders. Thus, the Series E preferred stock is not within the scope of ASC 480-10-S99 and will be classified in stockholders’ equity.
The Series E preferred stock was issued together with warrants to purchase 8,484,840 shares of common stock (the “Series E warrants”). Since the Series E preferred stock and the Series E warrants were classified in stockholders’ equity, the gross proceeds from the financing were allocated between the Series E preferred stock and the Series E warrants based on their relative fair values at the time of the November 9, 2012 Series E financing. The fair value of the Series E warrants was computed using the Black-Scholes Model and was determined to be $2,949,000. The $2,322,000 prorated value of the Series E warrants was recorded as additional paid-in capital.
The Series E preferred stock was then considered under ASC 470-20 to determine if a BCF existed. As of the transaction date, a BCF of $1,262,000 was computed using the initial stated conversion rate. Since the conversion feature is immediately exercisable, the $1,262,000 BCF was accreted immediately to preferred dividends.
The following is a summary of the changes in the Series E preferred stock during 2012 (in thousands):


Gross proceeds from November 9, 2012 Series E financing (including $1,061 paid for the warrants)		$	7,000
Less — allocation of proceeds to:
fair value allocated to warrants			(2,322	)
beneficial conversion feature			(1,262	)
transaction costs			(977	)

Net proceeds allocated to Series E preferred stock			2,439
Accretion of beneficial conversion feature			1,262

Carrying Value of Series E preferred stock — November 9, 2012		$	3,701

Carrying Value of Series E preferred stock — December 31, 2012		$	3,701

The effects of the extinguishment of the Series E preferred stock during 2013 are discussed in Note 14.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	9. Commitments and Contingencies
	(a) Lease Commitments
	In June 2007, the Company relocated its operations to a newly leased facility with a lease term through May 31, 2014. During 2013, 2012 and 2011, rent expense, including real estate taxes, was $1,601,000, $1,596,000 and $1,582,000, respectively. As part of the lease, the Company is required to restrict approximately $311,000 of cash for a security deposit as of December 31, 2013. The lease is classified as an operating lease. Future minimum commitments as of December 31, 2013 under the Company’s lease agreement are approximately:


	December 31,	Operating
		Lease
		(In thousands)
	2014	$	628

		$	628

	The operating lease was amended on February 21, 2014 to, among other things, extend the expiration date to August 31, 2017 subject to a three-year renewal option exercisable by the Company. After giving effect to the extension, future minimum commitments under the operating lease will amount to approximately $1,153,000, $1,517,000, $1,546,000 and $1,043,000 during 2014, 2015, 2016 and 2017, respectively.
	(b) External Collaborations
	The Company is a party to six royalty-bearing license agreements under which it has acquired rights to antisense related patents, patent applications, and technology. Each of these in-licenses automatically terminates upon the expiration of the last to expire patent included in the license. The Company has annual minimum payments due under these agreements of $35,000 in 2014 and $10,000 in each of 2015 and 2016.
	(c) Contract Obligations
	The Company has an employment agreement, which expires October 2016, with its president and chief executive officer. As of December 31, 2013, future minimum commitments under this agreement were approximately $571,000 for each of the years ended December 31, 2014 and 2015, and $457,000 for the year ended December 31, 2016.
	(d) Related-Party Transactions
	In November 2011, the Company issued and sold shares of Series D preferred stock and Series D warrants pursuant to a Convertible Preferred Stock and Warrant Purchase Agreement with Pillar Pharmaceuticals I, L.P. (“Pillar I”), an investment partnership managed by one of the Company’s directors and significant shareholders, which is described in Note 15. In November, 2012, the Company issued and sold shares of Series E preferred stock and Series E warrants pursuant to a Convertible Preferred Stock and Warrant Purchase Agreement with Pillar Pharmaceuticals II, L.P. (“Pillar II”), an investment partnership managed by two of the Company’s directors and one of its significant shareholders, which is described in Note 15.
	In connection with the Company’s follow-on underwritten public offering on May 7, 2013, the Company sold 5,000,000 shares of common stock and warrants to purchase 5,000,000 shares of common stock at $0.47 per share for an aggregate purchase price of $2,500,000 to Pillar Pharmaceuticals III, L.P. (“Pillar III”) and an entity affiliated with Pillar III (together with Pillar III, the “Pillar III Entities”), which is described in Note 15. In connection with the Company’s follow-on underwritten public offering on September 30, 2013, the Company sold 1,774,193 shares of common stock for an aggregate purchase price of $2,750,000 to Pillar Pharmaceuticals IV, L.P. (“Pillar IV”) and an entity affiliated with Pillar IV (together with Pillar IV, the “Pillar IV Entities”), which is described in Note 15.

	Youssef El Zein, a member of the Company’s board of directors, is a director and controlling stockholder of Pillar Invest Corporation (“Pillar Invest”), which is the general partner of Pillar I, Pillar II, Pillar III and Pillar IV. Mr. El Zein has voting and investment control over the securities beneficially owned by the Pillar III Entities and the Pillar IV Entities. In addition, Abdul-Wahab Umari, also a member of the Company’s board of directors, is a managing partner of Pillar Invest.
	The Company paid certain directors consulting fees of approximately $1,000 and $32,000 in 2012 and 2011, respectively. The $1,000 paid in 2012 was associated with services performed in 2011. The Company did not pay any consulting fees to directors in 2013. The Company issued common stock in lieu of director board and committee fees of approximately $26,000, $1,000, and $38,000 during 2013, 2012 and 2011, respectively.
	Additional information on related party transactions associated with the April 2013 agreements between the Company and the Pillar Entities (as defined in Note 14) is included in Note 14.

Income_Taxes

Income Taxes	12 Months Ended
Income Taxes	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	10. Income Taxes
	Subject to the limitations described below, at December 31, 2013, the Company had cumulative net operating loss carryforwards (“NOLs”) of approximately $190,645,000 and $82,292,000 available to reduce federal and state taxable income which expire through 2033. In addition, the Company had cumulative federal and state tax credit carryforwards of $5,887,000 and $5,286,000, respectively, available to reduce federal and state income taxes which expire through 2033 and 2028, respectively. The federal and state NOLs include approximately $1,942,000 and $73,000, respectively, of deductions related to the exercise of stock options subsequent to the adoption of ASC 718, “Stock Compensation.” This amount represents an excess tax benefit as defined under ASC 718 and has not been included in the gross deferred tax asset reflected for NOLs.
	The Tax Reform Act of 1986 contains provisions that limit the amount of net operating loss and tax credit carryforwards that companies may utilize in any one year in the event of cumulative changes in ownership over a three-year period in excess of 50%. The Company has completed several financings since the effective date of the Tax Reform Act of 1986, which as of December 31, 2013, have resulted in ownership changes in excess of 50%, and that will significantly limit the Company’s ability to utilize its NOL and tax credit carryforwards. The Company has not prepared an analysis to determine the effect of the ownership change limitation on its ability to utilize its net operating loss and tax credit carryforwards as of December 31, 2013. Ownership changes in future periods may place additional limits on the Company’s ability to utilize NOLs and tax credit carryforwards.
	As of December 31, 2013 and 2012, the components of the deferred tax assets are approximately as follows:


		2013			2012
		(In thousands)
	Operating loss carryforwards	$	68,500		$	61,717
	Tax credit carryforwards		9,376			8,455
	Other		5,078			4,935

			82,954			75,107
	Valuation allowance		(82,954	)		(75,107	)

		$	—		$	—

	The Company has provided a valuation allowance for its deferred tax asset due to the uncertainty surrounding the ability to realize this asset. The increases in the deferred tax assets and the valuation allowance in the current year are primarily attributable to additional NOLs and credits.

	The difference between the 34% U.S. federal corporate tax rate and the Company’s effective tax rate is as follows for the years ended December 31, 2013, 2012 and 2011:


		2013			2012			2011
	Expected federal income tax rate		(34.0	)%		(34.0	)%		(34.0	)%
	Expiring credits and NOLs		0.2			116.3			66.3
	Change in valuation allowance		43.1			(76.6	)		(22.5	)
	Federal and state credits		(5.0	)		(0.6	)		(3.3	)
	State income taxes, net of federal benefit		(5.1	)		(5.2	)		(5.4	)
	Permanent differences		0.9			0.1			(1.0	)
	Other		(0.1	)		—			(0.1	)

	Effective tax rate		0	%		0	%		0	%

	The Company applies ASC 740-10, “Accounting for Uncertainty in Income Taxes, an interpretation of ASC 740.” ASC 740-10 clarifies the accounting for uncertainty in income taxes recognized in financial statements and requires the impact of a tax position to be recognized in the financial statements if that position is more likely than not of being sustained by the taxing authority. The Company had no unrecognized tax benefits resulting from uncertain tax positions at December 31, 2013 and 2012.
	The Company has not, as of yet, conducted a study of its research and development credit carryforwards. Such a study might result in an adjustment to the Company’s research and development credit carryforwards, however, until a study is completed and any adjustment is known, no amounts are being presented as an uncertain tax position under ASC 740-10. A full valuation allowance has been provided against the Company’s research and development credits and, if an adjustment is required, this adjustment would be offset by an adjustment to the valuation allowance. Thus, there would be no impact to the statements of operations and comprehensive loss if an adjustment was required.
	The Company files income tax returns in the U.S. federal and Massachusetts jurisdictions. The Company is no longer subject to tax examinations for years before 2010, except to the extent that it utilizes NOLs or tax credit carryforwards that originated before 2010. The Company does not believe there will be any material changes in its unrecognized tax positions over the next 12 months. The Company has not incurred any interest or penalties. In the event that the Company is assessed interest or penalties at some point in the future, they will be classified in the statements of operations and comprehensive loss as general and administrative expense.
	The American Taxpayer Relief Act of 2012 (the “Act”) was enacted on January 2, 2013. The Act retroactively reinstated the federal research and development credit from January 1, 2012, through December 31, 2013. The effect of the change in the tax law related to fiscal 2012 was $475,000, which increased the deferred tax asset and related valuation allowance in the first quarter of 2013, the quarter in which the law was enacted.

Employee_Benefit_Plan

Employee Benefit Plan	12 Months Ended
Employee Benefit Plan	Dec. 31, 2013
Compensation And Retirement Disclosure [Abstract]	'
Employee Benefit Plan	'
	11. Employee Benefit Plan
	The Company has an employee benefit plan under Section 401(k) of the Code. The plan allows employees to make contributions up to a specified percentage of their compensation. Under the plan, the Company matches a portion of the employees’ contributions up to a defined maximum. The Company is currently contributing up to 3% of employee base salary, by matching 50% of the first 6% of annual base salary contributed by each employee. Approximately $83,000, $106,000, and $132,000 of 401(k) benefits were charged to operating expenses during 2013, 2012 and 2011, respectively.

Net_Loss_per_Common_Share_Appl

Net Loss per Common Share Applicable to Common Stockholders	12 Months Ended
Net Loss per Common Share Applicable to Common Stockholders	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Net Loss per Common Share Applicable to Common Stockholders	'
	12. Net Loss per Common Share Applicable to Common Stockholders
	For the years ended December 31, 2013 and 2012, basic and diluted net loss per common share applicable to common stockholders is computed using the weighted average number of shares of common stock outstanding during the period. Diluted net loss per common share applicable to common stockholders is the same as basic net loss per common share applicable to common stockholders as the effects of the Company’s potential common stock equivalents are antidilutive. Total antidilutive securities were 85,974,000 and 33,332,000 at December 31, 2013 and 2012, respectively, and consisted of stock options, preferred stock and warrants.
	For the year ended December 31, 2013, net loss per common share applicable to common stockholders reflects $1,750,000 related to the loss on extinguishment of the Series D preferred stock and the Series E preferred stock that the Company issued in November 2011 and November 2012, respectively, that has been charged to net loss applicable to common stockholders as a preferred stock dividend and $756,000 and $360,000, respectively, in dividends accrued on shares of Series D preferred stock and Series E preferred stock. For the year ended December 31, 2012, net loss per common share applicable to common stockholders reflects $3,210,000 in preferred stock accretion and dividends, including $1,238,000 related to the BCF of the Series D preferred stock that has been accreted to preferred dividends, $670,000 in dividends payable on shares of the Series D preferred stock, $1,262,000 related to the BCF of the Series E preferred stock that has been accreted to preferred dividends and $40,000 in dividends payable on shares of the Series E preferred stock.

Supplemental_Disclosure_of_Cas

Supplemental Disclosure of Cash Flow Information	12 Months Ended
Supplemental Disclosure of Cash Flow Information	Dec. 31, 2013
Supplemental Cash Flow Elements [Abstract]	'
Supplemental Disclosure of Cash Flow Information	'
	13. Supplemental Disclosure of Cash Flow Information
	Supplemental disclosure of cash flow information for the periods presented is as follows:


		Year Ended December 31,
		2013		2012		2011
		(In thousands)
	Supplemental disclosure of non cash financing and investing activities:

	Extinguishment of Series D and Series E preferred stock and issuance of related warrants	$	5,921	$	—	$	—

	Accrued 2013 financing transaction costs paid in 2014	$	100	$	—	$	—

	Accretion of Series D redeemable preferred stock beneficial conversion feature	$	—	$	1,238	$	4,445

	Accretion of Series E preferred stock beneficial conversion feature	$	—	$	1,262	$	—

	Reclassification of Series D warrants from liabilities to stockholders’ equity	$	—	$	503	$	—

April_2013_Pillar_Agreements

April 2013 Pillar Agreements	12 Months Ended
April 2013 Pillar Agreements	Dec. 31, 2013
Text Block [Abstract]	'
April 2013 Pillar Agreements	'
	14. April 2013 Pillar Agreements
	In April 2013, the Company entered into two agreements (the “Pillar Agreements”) with Pillar I, Pillar II and an entity affiliated with Pillar I and Pillar II (together with Pillar I and Pillar II, the “Pillar Entities”). The agreements, including the Company’s obligations to issue the warrants under the Pillar Agreements, became effective upon the consummation of the follow-on underwritten public offering of the Company’s securities on May 7, 2013. Mr. El Zein, a member of the Company’s board of directors, is a director and controlling stockholder of Pillar Invest, which is the general partner of Pillar I and Pillar II, and is a limited partner of Pillar I and Pillar II. Mr. El Zein has voting and investment control over the securities beneficially owned by the Pillar Entities. In addition, Abdul-Wahab Umari, also a member of the Company’s board of directors, is a managing partner of Pillar Invest.
	Under the first agreement entered into with Pillar I and Pillar II (the “April 22, 2013 Pillar Agreement”), Pillar I, as the sole holder of the Company’s Series D preferred stock, irrevocably waived and agreed to not exercise the rights, powers, preferences and other terms of the Series D preferred stock under Section 6 of the Series D Certificate of Designations, including without limitation the right to require the Company to purchase all or any portion of the shares of its Series D preferred stock at a price equal to the original Series D preferred stock purchase price per share plus all accrued or declared but unpaid dividends thereon upon the occurrence of specified fundamental changes such as mergers, consolidations, business combinations, stock purchases or similar transactions resulting in a person or group unaffiliated with any holder of Series D preferred stock owning 66.67% or more of the outstanding voting securities of the Company or successor entity (the “Series D Redemption Rights”).
	Under the April 22, 2013 Pillar Agreement, the Company agreed to seek approval and each of Pillar I and Pillar II agreed to vote in favor, of the following proposals at the Company’s 2013 Annual Meeting:

		•		amendments to the Series D Certificate of Designations for the Series D preferred stock to:

		•		modify the dividend provisions of the Series D Certificate of Designations to change the date after which the Company may elect to pay dividends in shares of its common stock from December 31, 2014 to October 1, 2013, and to allow for the payment of such dividends in shares of a to-be-created new series of non-voting preferred stock in the event that payment of such dividends may not be made in shares of its common stock as a result of the application of the beneficial ownership and voting power limitations set forth the Series D Certificate of Designations; and

		•		modify the Series D Certificate of Designations to provide, in the event of a sale of the Company, for the distribution of any assets that remain available for distribution to its stockholders, after payment to the holders of its Series A convertible preferred stock and any other class of its capital stock that ranks senior to its Series D preferred stock, to the holders of the Company’s Series D preferred stock on a pro rata basis with the holders of its common stock, Series E preferred stock and such new series of non-voting preferred stock; and

		•		amendments to the Series E Certificate of Designations to:

		•		modify the dividend provisions of the Series E Certificate of Designations to allow for the payment of dividends in shares of its common stock commencing October 1, 2013; and

		•		allow for the payment of dividends in shares of a to-be-created new series of non-voting preferred stock in the event that payment of such dividends may not be made in shares of its common stock as a result of the application of the beneficial ownership and voting power limitations set forth in the Series E Certificate of Designations.
	Under the second agreement with the Pillar Entities (the “April 30, 2013 Pillar Agreement”), Pillar I irrevocably waived the right of the holders of the Series D preferred stock under Section 2.1 of the Series D Certificate of Designations to receive, in the event of a voluntary or involuntary liquidation, dissolution or winding up of the Company (a “Liquidation”), an amount per share of Series D preferred stock equal to the original issue price of such share of Series D preferred stock plus any dividends accrued or declared but unpaid thereon to the extent such amount is greater than the amount that would have been payable with respect to such share had all shares of Series D preferred stock been converted into shares of the Company’s common stock immediately prior to such Liquidation, and that upon a Liquidation the holders of the Series D preferred stock will receive an amount per share of Series D preferred stock equal to the amount that would be payable with respect to such share had all shares of Series D preferred stock been converted into shares of common stock immediately prior to such Liquidation.
	In addition, under the April 30, 2013 Pillar Agreement, Pillar II and the entity affiliated with Pillar I and Pillar II, as the holders of 100% of the Company’s Series E preferred stock, irrevocably waived the right of the holders of the Series E preferred stock under Section 2.1.1 of the Series E Certificate of Designations to receive, in the event of a Liquidation, an amount per share of Series E preferred stock equal to the original issue price of such share of Series E preferred stock plus any dividends accrued or declared but unpaid thereon to the extent such amount is greater than the amount that would have been payable with respect to such share had all shares of Series E preferred stock been converted into shares of common stock immediately prior to such Liquidation, and that upon a Liquidation the holders of the Series E preferred stock will receive under Section 2.1 of the Series E Certificate of Designations an amount per share of Series E preferred stock equal to the amount that would be payable with respect to such share had all shares of Series E preferred stock been converted into shares of common stock immediately prior to such Liquidation.
	In accordance with the terms of the Pillar Agreements, the Company sought approval from its stockholders of amendments to the Series D Certificate of Designations and Series E Certificate of Designations to effect the changes described above to the dividend and liquidation provisions of the Company’s Series D preferred stock and Series E preferred stock, the redemption rights of the holders of its Series D preferred stock and the rights of the holders of its Series D preferred stock to distributions in the event of a sale of the Company. These matters were approved at the 2013 Annual Meeting that took place on July 26, 2013. Additional information on the amendments to the Series D Certificate of Designations and Series E Certificate of Designations that were approved by the Company’s stockholders at the 2013 Annual Meeting is included in Note 16.
	Under the April 22, 2013 Pillar Agreement, in consideration of the agreements of Pillar I and II under the April 22, 2013 Pillar Agreement and the delivery of the waiver by Pillar I, and for no additional cash consideration, the Company issued to Pillar I warrants, the Pillar I Warrants, to purchase up to 1,000,000 shares of the Company’s common stock at an exercise price of $0.61 per share.
	In addition, under the April 30, 2013 Pillar Agreement, in consideration of the agreements of the Pillar Entities under the April 30, 2013 Pillar Agreement and the delivery of the waivers by the Pillar Entities, and for no additional cash consideration, the Company issued to the Pillar Entities warrants (the “Additional Pillar Warrants,” and together with the Pillar I Warrants, the “Pillar Warrants”), to purchase up to an aggregate of 1,000,000 shares of the Company’s common stock at an exercise price of $0.79 per share.
	The Pillar Warrants became exercisable immediately upon issuance. The Pillar I Warrants will expire if not exercised on or prior to the fifth anniversary from the date of issuance and the Additional Pillar Warrants will expire if not exercised on or prior to June 1, 2014. The Pillar I Warrants provide that, after the second anniversary of the date of issuance, the Company may redeem such Pillar I Warrants for $0.01 per share of common stock issuable on exercise of such Pillar I Warrants following notice to the holder thereof if the closing price of its common stock for 20 or more trading days in a period of 30 consecutive trading days is greater than or equal to $2.80 per share.
	In connection with the Pillar Agreements, the Company filed a registration statement that became effective on July 10, 2013, registering the resale of the shares of common stock issuable upon exercise of the Pillar Warrants.

	The amendments to the Series D Certificate of Designations and Series E Certificate of Designations did not become effective until the amendments were approved by the Company’s stockholders at the 2013 Annual Meeting, which occurred during the Company’s fiscal quarter that began on July 1, 2013.
	Since Pillar I irrevocably waived and agreed to not exercise the Series D Redemption Rights, the Company reassessed its accounting in May 2013 for the Series D preferred stock, which had been classified as temporary equity in the Company’s condensed balance sheet because the Series D Redemption Rights represented a contingent put feature that was outside the Company’s control. Upon effectiveness of this waiver, the contingent put feature ceased to exist.
	In addition, the Pillar Entities irrevocably waived the liquidation preferences of both the Series D preferred stock and the Series E preferred stock. The Company concluded that these irrevocable waivers of the Series D Redemption Rights and the Series D and Series E liquidation preferences, which became effective on May 7, 2013, represented changes to the fundamental terms of both the Series D preferred stock and the Series E preferred stock. As a result, the Company has accounted for these irrevocable waivers as an extinguishment of the Series D preferred stock and the Series E preferred stock and changed the classification of the Series D preferred stock from temporary equity to permanent equity. The Company compared (1) the sum of the fair values of the Series D preferred stock, the Series E preferred stock and the Pillar Warrants immediately after the effectiveness of the waivers to (2) the sum of the carrying values of the Series D preferred stock and Series E preferred stock immediately prior to the effectiveness of the waivers on May 7, 2013. The Company recorded the excess of the aggregate fair value of the preferred stock plus the Pillar Warrants immediately after the effectiveness of the waivers over the aggregate carrying value of the preferred stock immediately prior to May 7, 2013 as a loss on extinguishment and classified the fair values, immediately after the effectiveness of the waivers, of the Series D preferred stock, the Series E preferred stock and the Pillar Warrants within permanent equity on its balance sheet.
	The effect of this extinguishment accounting on the Company’s financial statements was to (1) remove the $5,921,000 carrying value of the Series D preferred stock immediately prior to the extinguishment from temporary equity; (2) record the $5,464,000 fair value of the Series D preferred stock immediately after the extinguishment in permanent equity (“equity”); (3) remove the $3,701,000 carrying value of the Series E preferred stock immediately prior to the extinguishment from equity; (4) record the $5,528,000 fair value of the Series E preferred stock immediately after the extinguishment in equity; (5) record the $380,000 fair value of the Pillar Warrants in equity; and (6) record a $1,750,000 extinguishment loss to net loss applicable to common stockholders. These accounting entries resulted in a $5,921,000 net increase in stockholders’ equity on its balance sheet.
	The Company determined the fair value of the Series D preferred stock and the Series E preferred stock as of May 7, 2013, the date the above described waivers became effective, based on the Option Pricing Method (“OPM”) which is a market based approach to imply the aggregate equity value of the Company by using the closing price of the Company’s publicly traded common stock as of the May 7, 2013 valuation date. Under the OPM, the fair value of preferred stock and common stock are determined based on the net value of a series of call options representing the present value of the expected future returns to each shareholder class. Essentially, the rights of the common stock are equivalent to a call option on any value of the Company above any cumulative preferred stock liquidation preference. The analysis involves calculating the equity value breakeven points at which the various equity classes would participate, or convert in the case of preferred stock, or exercise in the case of stock options and warrants.

	The Company used the Black-Scholes Model to compute the fair value of the Pillar Warrants as of the May 7, 2013 effective date on which the Pillar Warrants were issued based on the following assumptions and other inputs:


			Pillar I			Additional
			Warrants			Pillar
						Warrants
	Common stock price		$	0.57		$	0.57
	Warrant exercise price		$	0.61		$	0.79
	Term of warrant (years)			5			1.1
	Expected volatility			62	%		67	%
	Average risk free interest rate			0.8	%		0.1	%
	Expected dividend yield			—			—
	Expected percentage of warrants to be exercised			100	%		100	%
	The closing price of the Company’s common stock is readily determinable since it is publicly traded. The warrant exercise prices and the warrant terms are readily determinable from the warrant agreements. The expected volatility is based on the actual stock-price volatility over a period equal to the greater of the term of the warrant or three years. The assumed risk-free interest rate is based on the U.S. Treasury security rate with a term equal to the term of the warrant. The assumed dividend yield of zero is based on the fact that the Company has never paid cash dividends to common stockholders and has no present intention to pay cash dividends to common stockholders. The Company assumed that future financings would dilute the warrant holder’s ownership in the Company such that the 19.99% ownership limitation would not prevent the warrant holder from exercising all of the warrants during the term of the warrants.

Financings

12 Months Ended

Dec. 31, 2013

Text Block [Abstract]

Financings

15. Financings

September 30, 2013 Follow-on Underwritten Public Offering

On September 30, 2013, the Company closed a follow-on underwritten public offering, in which it sold 13,727,251 shares of common stock at a price to the public of $1.55 per share and pre-funded warrants to purchase up to 4,175,975 shares of common stock at a price to the public of $1.54 per share for aggregate gross proceeds of $27.7 million. The pre-funded warrants have an exercise price of $0.01 per share and will expire if not exercised by September 30, 2020. The estimated net proceeds to the Company from the offering, after deducting underwriters’ discounts and commissions and offering costs and expenses and excluding the proceeds of the exercise of the warrants, if any, were approximately $25.7 million.

May 7, 2013 Follow-on Underwritten Public Offering

On May 7, 2013, the Company closed a follow-on underwritten public offering, in which it sold 17,500,000 shares of common stock, together with matching warrants to purchase up to 17,500,000 shares of common stock, and pre-funded warrants to purchase up to 15,816,327 shares of common stock, together with matching warrants to purchase up to 15,816,327 shares of common stock, for aggregate gross proceeds of $16.5 million as follows:

Combined

Common

Pre-funded

Matching

Price to the

Stock

Warrants

Public

(per share of

Common

Stock)

Common stock and matching warrants sold (shares)

0.5

17,500,000

—

17,500,000

Pre-funded warrants and matching warrants sold (shares)

0.49

—

15,816,327

Total (shares)

17,500,000

15,816,327

33,316,327

Warrant exercise price (per share)

—

0.01

0.47

Term of warrant (years)

—

The estimated net proceeds to the Company from the offering, after deducting underwriters’ discounts and commissions and offering costs and expenses and excluding the proceeds of the exercise of the warrants, if any, were approximately $14.5 million.

The warrants and the pre-funded warrants each provide that, after the second anniversary of the date of issuance, the Company may redeem the warrants for $0.01 per share of common stock issuable on exercise of the warrants following 30 days’ prior written notice to the holder if the closing price of the common stock for 20 or more trading days in a period of 30 consecutive trading days is greater than or equal to $2.80.

Warrant Exercises

Warrants to purchase 7,160,000 shares of common stock were exercised during 2013. The Company received $3,365,000 in proceeds from the exercise of these warrants. There were no warrant exercises during 2012 and 2011.

Series E Preferred Stock and Warrant Financing

In November 2012, the Company entered into a Convertible Preferred Stock and Warrant Purchase Agreement (the “Series E Purchase Agreement”) with Pillar II and the other purchaser named therein (together, the “Series E Purchasers”). Pursuant to the Series E Purchase Agreement, the Company issued and sold to the Series E Purchasers, for an aggregate purchase price of approximately $7.0 million, 424,242 shares of its Series E preferred stock and Series E warrants to purchase up to 8,484,840 shares of its common stock. The shares of Series E preferred stock are convertible, subject to limitations, into an aggregate of 8,484,840 shares of common stock at a conversion price of $0.70 per share. The initial exercise price of the Series E warrants is $0.70 per share. The Series E warrants are exercisable immediately, and will expire if not exercised on or prior to November 9, 2017. The Company has agreed to pay to the holders of the Series E preferred stock quarterly dividends payable in cash in arrears at the rate of 4.6% per annum with the first dividend payment being due on March 31, 2013. Under the terms of the Series D preferred stock, any dividends paid to the holders of Series E preferred stock would also be paid to the holders of the Series D preferred stock on an as-converted to common stock basis. The Company agreed that, at the 2013 Annual Meeting, it would, among other things, propose an amendment to the Series D Certificate of Designations to, among other things, modify the terms of the Series D preferred stock that require payment of dividends to Series D preferred stockholders upon payment of dividends to Series E stockholders. Since the stockholders of the Company approved the amendment to the Series D Certificate of Designations, the dividend rate with respect to the Series E preferred dividends increased from the 4.6% to the rate of 8% per annum. The net proceeds to the Company, excluding the proceeds of any exercise of the warrants, were approximately $6.0 million. The Company intends to use these funds for research and clinical development activities, the manufacturing of its product candidates, working capital and general corporate purposes, including the advancement of the Company’s autoimmune disease program in at least two indications.

The securities offered by the Company in the private placement were not registered under the Securities Act of 1933, as amended (the “Securities Act”), and cannot be offered or sold in the United States absent registration or an applicable exemption from registration requirements. In January 2013, the Company filed a registration statement with the Securities and Exchange Commission that became effective on January 17, 2013, registering the resale of the shares of common stock issuable upon conversion of the Series E preferred stock and the shares of common stock issuable upon exercise of the Series E warrants issued in the private placement.

The Company is subject to specified cash penalties if it fails to maintain an effective registration statement with the Securities and Exchange Commission registering the resale of the shares of Common Stock issuable upon conversion of the Series E preferred stock and the shares of Common Stock issuable upon exercise of the Series E warrants. Such penalties are limited to a cumulative maximum penalty equal to 10% of the aggregate purchase price paid to the Company for the Series E preferred stock. The Company is required to maintain the registration statement’s effectiveness until no unregistered shares of Common Stock issued or issuable upon conversion of the Series E preferred stock or upon exercise of the Series E warrants remain outstanding or issuable, as applicable.

Series D Preferred Stock and Warrant Financing

In November 2011, the Company entered into a Convertible Preferred Stock and Warrant Purchase Agreement (the “Series D Purchase Agreement”) with Pillar I. Pursuant to the Series D Purchase Agreement, the Company issued and sold to Pillar I, for an aggregate purchase price of $9.5 million, 1,124,260 shares of its Series D preferred stock initially convertible into 5,621,300 shares of its common stock, and Series D warrants to purchase 2,810,650 shares of its common stock. Each share of Series D preferred stock was initially convertible, subject to limitations, at a conversion price of $1.63 per share. The initial exercise price of the Series D warrants was $1.63 per share.

The sale of shares of Series E preferred stock and Series E warrants in the Company’s November 2012 Series E financing triggered anti-dilution adjustments under the terms of the Series D preferred stock and the Series D warrants. The anti-dilution adjustment under the Series D preferred stock resulted in the conversion price of the Series D preferred stock being reduced and fixed at $1.46 per share, and such shares no longer being subject to any anti-dilution adjustments. Each share of Series D preferred stock became convertible into 5.5736 shares of the Company’s common stock and, as a result, the 1,124,260 shares of Series D preferred stock became convertible, subject to limitations, into 6,266,175 shares of the Company’s common stock. The anti-dilution adjustment under the Series D warrants resulted in the exercise price of the Series D warrants being reduced and fixed at the minimum $1.46 per share and the Series D warrants no longer being subject to any anti-dilution adjustments.

The net proceeds to the Company, excluding the proceeds of any exercise of the Series D warrants, were approximately $9.1 million which was allocated as described in Note 7(a). The Company used these funds for research and product development activities, including costs of conducting preclinical studies and clinical trials, and for general corporate purposes.

The securities offered by the Company in the private placement were not registered under the Securities Act and cannot be offered or sold in the United States absent registration or an applicable exemption from registration requirements. In December 2011, the Company filed a registration statement with the Securities and Exchange Commission that became effective on December 21, 2011, registering the resale of the shares of common stock issuable upon conversion of the Series D preferred stock and the shares of common stock issuable upon exercise of the warrants issued in the private placement. In February 2013, the Company filed a registration statement with the Securities and Exchange Commission that became effective on February 8, 2013, covering the resale of additional shares of common stock issuable upon conversion of the Series D preferred stock.

The Company is subject to specified cash penalties if it fails to maintain an effective registration statement with the Securities and Exchange Commission registering the resale of the shares of common stock issuable upon conversion of the Series D preferred stock and the shares of common stock issuable upon exercise of the Series D warrants. Such penalties are limited to a cumulative maximum penalty equal to 10% of the aggregate purchase price paid to the Company by Pillar I for the Series D preferred stock. The Company is required to maintain the registration statement’s effectiveness until no unregistered shares of common stock issued or issuable upon conversion of the Series D preferred stock or upon exercise of the Series D warrants remain outstanding or issuable, as applicable.

2013_Annual_Meeting_of_Stockho

2013 Annual Meeting of Stockholders	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
2013 Annual Meeting of Stockholders	'
	16. 2013 Annual Meeting of Stockholders
	At the 2013 Annual Meeting that took place on July 26, 2013, the Company’s stockholders approved the following:

		•	an amendment to the Company’s restated certificate of incorporation to increase the number of authorized shares of common stock from 140,000,000 to 280,000,000;

		•	a non-binding, advisory proposal on the compensation of the Company’s named executive officers;

		•	the 2013 Stock Incentive Plan;

		•	the ratification of the appointment of Ernst & Young LLP as the independent registered public accounting firm for the Company for the fiscal year ending December 31, 2013;

		•	amendments (collectively the “Series D Proposals”) to the Company’s restated certificate of incorporation amending the Series D Certificate of Designations to:

		•	provide that (a) the beneficial ownership limitation that prohibits the Company from paying a holder of the Company’s Series D preferred stock dividends payable in shares of the Company’s common stock to the extent the issuance of such shares would result in the holder of the Series D preferred stock and its affiliates beneficially owning more than 19.99% of the outstanding common stock (including shares of common stock issuable upon conversion of the Series D preferred stock) would be increased from 19.99% to 35% in the event that the Nasdaq Proposal (as defined below) was approved by the Company’s stockholders and (b) the beneficial ownership limitation that prohibits a holder of Series D preferred stock from converting its shares to the extent such conversion would result in the holder and its affiliates beneficially owning more than 19.99% of the outstanding common stock (including shares of common stock issuable upon conversion of the Series D preferred stock) would be increased from 19.99% to 35% in the event that the Nasdaq Proposal was approved by the Company’s stockholders;

		•	eliminate the requirement that the Company pay corresponding dividends to the holders of Series D preferred stock upon payment of dividends to holders of the Company’s Series E preferred stock;

		•	change the date after which the Company may elect to pay dividends in shares of common stock from December 31, 2014 to October 1, 2013, and to allow for the payment of such dividends in shares of a to-be-created new series of non-voting preferred stock in the event that payment of such dividends may not be made in shares of common stock as a result of the application of the beneficial ownership limitation set forth in the Series D Certificate of Designations;

		•	eliminate the right of holders of Series D preferred stock to receive, in the event of a liquidation, dissolution or winding up of the Company (a “Liquidation”), an amount per share of Series D preferred stock equal to the original issue price of such share of Series D preferred stock plus any dividends accrued or declared but unpaid thereon to the extent such amount is greater than the amount that would have been payable with respect to such share had all shares of Series D preferred stock been converted into shares of common stock immediately prior to such Liquidation, such that upon a Liquidation the holders of Series D preferred stock will receive an amount per share of Series D preferred stock equal to the amount that would be payable with respect to such share had all shares of Series D preferred stock been converted into shares of common stock immediately prior to such Liquidation; and

		•	provide, in the event of a sale of the Company, for the distribution of any assets that remain available for distribution to the Company’s stockholders, after payment to the holders of the Company’s Series A preferred stock and any other class of the Company’s capital stock that ranks senior to the Series D preferred stock, to the holders of Series D preferred stock on a pro rata basis with the holders of common stock, Series E preferred stock and such new series of non-voting preferred stock that was pari passu with the Series D preferred stock; and

		•	amendments (collectively the “Series E Proposals”) to the Company’s restated certificate of incorporation amending the Series E Certificate of Designations to:

		•	permit the Company to elect to pay dividends to the holders of Series E preferred stock in shares of common stock in lieu of cash beginning October 1, 2013, and to allow for the payment of such dividends in shares of a to-be-created new series of non-voting preferred stock in the event that payment of such dividends may not be made in shares of common stock as a result of the application of the beneficial ownership limitation set forth in the Series E Certificate of Designations; and

		•	eliminate the right of the holders of Series E preferred stock to receive, in the event of a Liquidation, an amount per share of Series E preferred stock equal to the original issue price of such share of Series E preferred stock plus any dividends accrued or declared but unpaid thereon to the extent such amount is greater than the amount that would have been payable with respect to such share had all shares of Series E preferred stock been converted into shares of common stock immediately prior to such Liquidation, such that upon a Liquidation the holders of Series E preferred stock will receive an amount per share of Series E preferred stock equal to the amount that would be payable with respect to such share had all shares of Series E preferred stock been converted into shares of common stock immediately prior to such Liquidation.
	The proposals submitted to the Company’s stockholders at the 2013 Annual Meeting to (i) amend the Company’s restated certificate of incorporation and bylaws to (a) declassify the Company’s board of directors, (b) provide that the Company’s stockholders may remove directors with or without cause following declassification of the Company’s board of directors and (c) eliminate the supermajority voting requirement for amending or repealing Article ELEVENTH of the Company’s restated certificate of incorporation (collectively, the “Declassification Proposal”) and (ii) approve the issuance and sale by the Company to certain affiliates of Pillar Invest Corporation (including prior issuances and sales of the Company’s securities to such affiliates in November 2011 and November 2012) of a number of shares of the Company’s common stock (including securities convertible into or exercisable for shares of the Company’s common stock) that is greater than 19.99% of the total number of issued and outstanding shares of common stock and of the outstanding voting power of the Company’s securities after such issuance and sale in accordance with Nasdaq Listing Rule 5635(b) (the “Nasdaq Proposal”), were not approved by the Company’s stockholders at the 2013 Annual Meeting.
	As a result of the approval by the Company’s stockholders of the Series D Proposals and Series E Proposals, certificates of amendment to the Series D Certificate of Designations and Series E Certificate of Designations were filed by the Company with the Delaware Secretary of State on July 26, 2013. Because the Nasdaq Proposal was not approved by the Company’s stockholders, the beneficial ownership limitation applicable to the Series D preferred stock and Series E preferred stock set forth in the Series D Certificate of Designations and Series E Certificate of Designations, each as amended, will remain at 19.99% and the threshold above which the holders of the Series D preferred stock and Series E preferred stock must vote any shares held by them in the same manner and percentage as the holders of the Company’s common stock vote on such matter, will remain at 19.99%.

Subsequent_Events

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2013
Subsequent Events [Abstract]	'
Subsequent Events	'
	17. Subsequent Events
	February 6, 2014 Conversion of Series D Preferred Stock
	On January 10, 2014, the Company notified Pillar I, the holder of all 1,124,260 shares of the Company’s authorized, issued and outstanding Series D preferred stock, of its intention to redeem the Series D preferred stock on February 10, 2014 in accordance with the terms of the Series D Certificate of Designations. Following this notice, Pillar I had the right to convert its Series D preferred stock into shares of the Company’s common stock at any time prior to the close of business on February 9, 2014. On February 6, 2014, Pillar I converted such shares into 6,266,175 shares of the Company’s common stock in accordance with the terms of the Series D Certificate of Designations. As a result of the conversion, no shares of the Company’s Series D preferred stock remain outstanding.
	February 10, 2014 Follow-on Underwritten Public Offering
	On February 10, 2014, the Company closed a follow-on underwritten public offering, in which it sold 7,867,438 shares of common stock at a price to the public of $4.00 per share and pre-funded warrants to purchase up to 2,158,750 shares of common stock at a price to the public of $3.99 per share for aggregate gross proceeds of $40.1 million. The pre-funded warrants have an exercise price of $0.01 per share and will expire if not exercised by February 10, 2021. The estimated net proceeds to the Company from the offering, after deducting underwriters’ discounts and commissions and other offering costs and expenses and excluding the proceeds of the exercise of the warrants, if any, were approximately $37.2 million.
	Warrant Exercises through February 15, 2014
	Warrants to purchase 1,893,802 shares of common stock were exercised between January 1, 2014 and February 15, 2014. The Company received $5,082,000 in proceeds from the exercise of these warrants.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2013
Accounting Policies [Abstract]	'
Basis of Presentation	'
	(a) Basis of Presentation
	The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure 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 from those estimates.
Cash, Cash Equivalents and Investments	'
	(b) Cash, Cash Equivalents and Investments
	The Company considers all highly liquid investments with maturities of 90 days or less when purchased to be “cash equivalents.” Cash and cash equivalents at December 31, 2013 and 2012 consisted of cash and money market funds.

	Management determines the appropriate classification of marketable securities at the time of purchase. Investments that the Company does not have the positive intent to hold to maturity are classified as “available-for-sale” and reported at fair market value. Available-for-sale investments are classified as long-term if their contractual maturity is greater than one year at the balance sheet date and the Company does not have the intent to sell them in order to fund current operations. Unrealized gains and losses associated with available-for-sale investments are recorded in “Accumulated other comprehensive income” on the accompanying balance sheets. The amortization of premiums and accretion of discounts, and any realized gains and losses and declines in value judged to be other-than-temporary, and interest and dividends for all available-for-sale securities are included in “Investment income, net” on the accompanying statements of operations. Investments that the Company intends to hold to maturity are classified as “held-to-maturity” investments. The Company had no “held-to-maturity” investments at either December 31, 2013 or 2012. The cost of securities sold is based on the specific identification method.
	The Company had no realized gains or losses from available-for-sale securities in 2013, 2012 or 2011. There were no losses or other-than-temporary declines in value included in “Investment income, net” for any securities for the three years ended December 31, 2013. The Company had no auction rate securities as of December 31, 2013 and 2012.
Restricted Cash	'
	(c) Restricted Cash
	As part of the Company’s lease arrangement for its office and laboratory facility, the Company is required to restrict cash held in a certificate of deposit securing a line of credit for the lessor. As of December 31, 2013 and 2012, the restricted cash amounted to $311,000 held in certificates of deposit securing a line of credit for the lessor. In February 2014, the lease term was extended to August 31, 2017. As a result, the restricted cash is included in non-current assets at December 31, 2013.
Depreciation and Amortization	'
	(d) Depreciation and Amortization
	Depreciation and amortization are computed using the straight-line method based on the estimated useful lives of the related assets. Laboratory and other equipment are depreciated over three to five years. Leasehold improvements are amortized over the remaining lease term or the related useful life, if shorter.
Revenue Recognition	'
	(e) Revenue Recognition
	For the years ended December 31, 2013, 2012 and 2011, alliance revenue consisted primarily of revenue from the reimbursement by licensees of costs associated with patent maintenance. The Company recognizes the reimbursement revenue during the period in which the related expenses are incurred.
Financial Instruments	'
	(f) Financial Instruments
	The fair value of the Company’s financial instruments is determined and disclosed in accordance with the three-tier fair value hierarchy specified in Note 2(m). The Company is required to disclose the estimated fair values of its financial instruments. The Company’s financial instruments consist of cash, cash equivalents, available-for-sale investments and receivables. The estimated fair values of these financial instruments approximate their carrying values as of December 31, 2013 and 2012, respectively. As of December 31, 2013 and 2012, the Company did not have any derivatives, hedging instruments or other similar financial instruments except for the Series D convertible preferred stock, the (“Series D preferred stock”), embedded features discussed in Note 7(a) and the Series E convertible preferred stock, the (“Series E preferred stock”) embedded features discussed in Note 8(g).
Comprehensive Income (Loss)	'
	(g) Comprehensive Income (Loss)
	Comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. Comprehensive income (loss) for the years ended December 31, 2013, 2012 and 2011 is comprised of reported net income (loss) and any change in net unrealized gains and losses on investments during each year, which is included in “Accumulated other comprehensive income” on the accompanying balance sheets. The Company applies ASU No. 2011-05, “Comprehensive Income” by presenting the components of net income and other comprehensive income as one continuous statement.
	The following table includes the changes in the accumulated balance of the component of other comprehensive (loss) gain for the years ended December 31, 2013 and 2011:


		Year ended December 31,
	(In thousands)	2013			2011
	Accumulated unrealized gain on available-for-sale securities at beginning of period	$	—		$	13
	Change during the period		(7	)		(13	)

	Accumulated unrealized loss on available-for-sale securities at end of period	$	(7	)	$	—

	There was no accumulated unrealized gain or loss on available-for-sale securities during 2012.
Net Income (Loss) per Common Share Applicable to Common Stockholders	'
	(h) Net Income (Loss) per Common Share applicable to Common Stockholders
	Basic and diluted net loss per common share applicable to common stockholders is computed using the weighted average number of shares of common stock outstanding during the period. Diluted net loss per common share applicable to common stockholders is the same as basic net loss per common share applicable to common stockholders for each of the three years ended December 31, 2013 as the effects of the Company’s potential common stock equivalents are antidilutive (see Note 12).
Segment Reporting	'
	(i) Segment Reporting
	The Company views its operations and manages its business as one operating segment. Accordingly, the Company operates in one segment, which is the business of discovering and developing novel therapeutics that modulate immune responses through TLRs. As a result, the financial information disclosed herein represents all of the material financial information related to the Company’s principal operating segment. For all of the periods presented, all of the Company’s revenues were generated in the United States. As of December 31, 2013 and 2012, all assets were located in the United States.
Stock-Based Compensation	'
	(j) Stock-Based Compensation
	The Company recognizes all share-based payments to employees and directors as expense in the statements of operations and comprehensive loss based on their fair values. The Company records compensation expense over an award’s requisite service period, or vesting period, based on the award’s fair value at the date of grant. The Company’s policy is to charge the fair value of stock options as an expense, adjusted for forfeitures, on a straight-line basis over the vesting period, which is generally four years for employees and three years for directors. Prior to December 2011, the vesting of all of the Company’s stock options was based on the passage of time and the employees’ continued service. In December 2011 and January 2012, the Company granted performance-based stock options to purchase 697,500 shares of common stock to employees. As of the grant date of such options, options to purchase 174,375 shares were to vest immediately upon the achievement of various performance conditions and options to purchase 523,125 shares were to vest over a three year service period upon the achievement of the same performance conditions. During 2012, three of the specified performance conditions were achieved. As a result, options to purchase 80,213 shares vested immediately, and options to purchase 240,640 shares began vesting over a three-year period in accordance with the terms of the performance-based options. As of June 30, 2013, the remaining performance-based options were forfeited as the remaining performance conditions had not been met by their deadlines. The Company recognizes expense over the implicit and explicit service periods for awards with performance conditions when the Company determines the achievement of the performance conditions to be probable.
	The Company recorded charges of $1,398,000, $2,096,000, and $2,725,000 for the years ended December 31, 2013, 2012 and 2011, respectively, for stock-based compensation expense attributable to share-based payments made to employees and directors.
	The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model. The following assumptions apply to the options to purchase 5,072,583, 187,500, and 1,671,000 shares of common stock granted to employees and directors during the years ended December 31, 2013, 2012 and 2011, respectively:


		2013			2012			2011
	Average risk free interest rate		1.3	%		0.8	%		1.4	%
	Expected dividend yield		—			—			—
	Expected lives (years)		5			5.6			6.3
	Expected volatility		67	%		62	%		64	%
	Weighted average grant date fair value of options granted during the period (per share)	$	0.89		$	0.51		$	0.75
	Weighted average exercise price of options granted during the period (per share)	$	1.55		$	0.92		$	1.26
	The expected lives of the options and the expected volatility are based on historical experience. All options granted during the three years ended December 31, 2013 were granted at exercise prices equal to the fair market value of the common stock on the dates of grant.
	The fair value of options that vested during 2013, 2012 and 2011 amounted to $1,429,000, $2,123,000 and $2,707,000, respectively. The intrinsic value of options exercised amounted to $150,000 during 2013. There were no option exercises in 2012 and 2011. As of December 31, 2013, there was $4,543,000 of unrecognized compensation cost related to nonvested stock-based compensation arrangements, which the Company expects to recognize over a weighted average period of 3.4 years.
Research and Development Expenses	'
	(k) Research and Development Expenses
	All research and development expenses, including amounts funded by research collaborations, are expensed as incurred. Research and development expenses are comprised of costs incurred in performing research and development activities, including drug development trials and studies, drug manufacturing, laboratory supplies, external research, payroll including stock-based compensation and overhead.
Concentration of Credit Risk	'
	(l) Concentration of Credit Risk
	Financial instruments that subject the Company to credit risk primarily consist of cash and cash equivalents and available-for-sale investments. The Company’s credit risk is managed by investing its cash and cash equivalents and marketable securities in highly rated money market instruments, certificates of deposit, corporate bonds, and debt securities. Due to these factors, no significant additional credit risk is believed by management to be inherent in the Company’s assets. As of December 31, 2013, all of the Company’s cash, cash equivalents and investments are held at one financial institution.
Fair Value of Assets and Liabilities	'
	(m) Fair Value of Assets and Liabilities
	The Company measures fair value at the price 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 using assumptions that market participants would use in pricing the asset or liability (the “inputs”) into a three-tier fair value hierarchy. This fair value hierarchy gives the highest priority (Level 1) to quoted prices in active markets for identical assets or liabilities and the lowest priority (Level 3) to unobservable inputs in which little or no market data exists, requiring companies to develop their own assumptions. Observable inputs that do not meet the criteria of Level 1, and include quoted prices for similar assets or liabilities in active markets or quoted prices for identical assets and liabilities in markets that are not active, are categorized as Level 2. Level 3 inputs are those that reflect the Company’s estimates about the assumptions market participants would use in pricing the asset or liability, based on the best information available in the circumstances. Valuation techniques for assets and liabilities measured using Level 3 inputs may include unobservable inputs such as projections, estimates and management’s interpretation of current market data. These unobservable Level 3 inputs are only utilized to the extent that observable inputs are not available or cost-effective to obtain. The Company applies ASU No. 2011-04, “Fair Value Measurement (Topic 820),” in its fair value measurements and disclosures.
	The table below presents the assets and liabilities measured and recorded in the financial statements at fair value on a recurring basis at December 31, 2013 and 2012 categorized by the level of inputs used in the valuation of each asset and liability.


	(In thousands)	Total			Quoted Prices			Significant			Significant
					in Active			Other			Unobservable
					Markets			Observable			Inputs
					for Identical			Inputs			(Level 3)
					Assets or			(Level 2)
					Liabilities
					(Level 1)
	December 31, 2013
	Assets
	Money market funds	$	25,201		$	25,201		$	—		$	—
	Short-term investments – commercial paper		1,997			—			1,997			—
	Short-term investments – corporate bonds		1,128						1,128
	Long-term investments		6,189			—			6,189			—

	Total Assets	$	34,515		$	25,201		$	9,314		$	—

	Total Liabilities	$	—		$	—		$	—		$	—

	December 31, 2012
	Assets
	Money market funds	$	9,990		$	9,990		$	—		$	—

	Total Assets	$	9,990		$	9,990		$	—		$	—

	Total Liabilities	$	—		$	—		$	—		$	—


	The Level 1 assets consist of money market funds, which are actively traded daily. The Level 2 assets consist of corporate bond and commercial paper investments whose fair value may not represent actual transactions of identical securities. The fair value of corporate bonds is generally determined from quoted market prices received from pricing services based upon quoted prices from active markets and/or other significant observable market transactions at fair value. The fair value of commercial paper is generally determined based on the relationship between the investment’s discount rate and the discount rates of the same issuer’s commercial paper available in the market which may not be actively traded daily. Since these fair values may not be based upon actual transactions of identical securities, they are classified as Level 2. Since any investments are classified as available-for-sale securities, any unrealized gains or losses are recorded in accumulated other comprehensive income or loss within stockholders’ equity on the balance sheet. The Company did not elect to measure any other financial assets or liabilities at fair value at December 31, 2013 or 2012.
	In connection with the sale of its Series D preferred stock in November 2011, the Company issued warrants which contained provisions for anti-dilution protection in the event that the Company issued other equity securities at a price below $1.46 per common share. Because of the potential adjustment to the warrant exercise price that could result from this anti-dilution protection, the warrants did not meet the criteria set forth in ASC 815-40, “Derivatives and Hedging – Contracts in Entity’s own Stock” to be considered indexed to the Company’s own stock. Accordingly, the Company recorded the fair value of these warrants as a liability. The Company estimated the fair value of these warrants at the issuance date using the Black-Scholes Model as the result was not significantly different than the use of a lattice or binomial model because the price protection provision is subject to a floor of $1.46 per share and the initial exercise price is $1.63. The Company characterized this warrant liability as a Level 3 liability because its fair value measurement was based, in part, on significant inputs not observed in the market and reflects the Company’s assumptions as to the expected warrant exercise price, the expected volatility of the Company’s common stock, the expected dividend yield, the expected term of the warrant instrument and the expected percentage of warrants to be exercised.
	The Company revalued the warrants at the end of each quarter using the Black-Scholes Model and recognized the change in the fair value of the warrants in the statements of operations and comprehensive loss as other income (expense). The following assumptions and other inputs were used to compute the fair value of the warrant liability as of the November 4, 2011 issuance date, December 31, 2011 and November 9, 2012 when it was transferred to stockholders’ equity, as explained below:


		November 4,			December 31,			November 9,
		2011			2011			2012
	Common stock price	$	1.92		$	1.05		$	0.7
	Expected warrant exercise price	$	1.46		$	1.46		$	1.46
	Remaining term of warrant (years)		5			4.8			4
	Expected volatility		61	%		58	%		59	%
	Average risk free interest rate		0.9	%		0.8	%		0.5	%
	Expected dividend yield		—			—			—
	Expected percentage of warrants to be exercised		100	%		100	%		100	%
	The closing price of the Company’s common stock is readily determinable since it is publicly traded. The exercise price of the warrant was initially set at $1.63 subject to adjustment to as low as the $1.46 minimum exercise price per share for diluting effects such as if in specified circumstances the Company sells its common stock at a price below $1.46 per share. The Company used the $1.46 minimum exercise price as an assumption in computing the fair value of the warrant at November 4, 2011 and December 31, 2011 because the Company’s common stock was trading below the $1.63 maximum exercise price as of such dates. The sale of shares of Series E preferred stock and Series E warrants in our November 2012 Series E financing triggered an anti-dilution adjustment under the terms of the Series D warrants, resulting in the exercise price of the Series D warrants being reduced and fixed at the minimum $1.46 per share and the Series D warrants no longer being subject to any anti-dilution adjustments. Since the exercise price of the Series D warrants became fixed, the Series D warrants then met the exception under ASC 815-40 as they were now “indexed to the company’s own stock” and met certain criteria for equity classification, thus the Series D warrants were marked to fair value through earnings as of November 9, 2012 and then reclassified to stockholders equity at that time. The estimated remaining term of the warrant is readily determinable from the warrant agreement as it is the remaining contractual term. The expected volatility is based on the actual stock-price volatility over a period equal to the greater of the remaining term of the warrant or three years. The assumed risk-free interest rate is based on the U.S. Treasury security rate with a term equal to the remaining term of the warrant. The assumed dividend yield of zero is based on the fact that the Company has never paid cash dividends to common stockholders and has no present intention to pay cash dividends to common stockholders. The Company assumed that future financings would dilute the warrant holder’s ownership in the Company such that the 19.99% ownership limitation would not prevent the warrant holder from exercising all of the warrants during the term of the warrants.
	Changes in the warrant liability from November 4, 2011 to November 9, 2012 were as follows:


	(In thousands)	Fair Value of
	(In thousands)	Warrant Liability
	Balance, November 4, 2011	$	3,152
	Decrease in fair value		(1,974	)

	Balance, December 31, 2011		1,178
	Decrease in fair value		(675	)
	Transfer to stockholders’ equity		(503	)

	Balance, November 9, 2012	$	—

	The fair value of the warrants decreased from $3,152,000 at November 4, 2011 to $1,178,000 at December 31, 2011 primarily due to decreases in the market price of the Company’s common stock resulting in the recognition of $1,974,000 in non-operating income in 2011. The fair value of the warrants decreased from $1,178,000 at December 31, 2011 to $503,000 at November 9, 2012 primarily due to decreases in the market price of the Company’s common stock and the remaining term of the warrants resulting in the recognition of $675,000 of non-operating income during the period ended November 9, 2012 at which time the $503,000 fair value of the warrant liability was transferred to stockholders’ equity.
	The Company did not elect to measure any other financial assets or liabilities at fair value.

Accounting for Uncertainty in Income Taxes	'
Accounting for Uncertainty in Income Taxes	The Company applies ASC 740-10, “Accounting for Uncertainty in Income Taxes, an interpretation of ASC 740.” ASC 740-10 clarifies the accounting for uncertainty in income taxes recognized in financial statements and requires the impact of a tax position to be recognized in the financial statements if that position is more likely than not of being sustained by the taxing authority. The Company had no unrecognized tax benefits resulting from uncertain tax positions at December 31, 2013 and 2012.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	12 Months Ended
Summary of Significant Accounting Policies (Tables)	Dec. 31, 2013
Accounting Policies [Abstract]	'
Change in Accumulated Balance of the Component of Other Comprehensive Loss	'
	The following table includes the changes in the accumulated balance of the component of other comprehensive (loss) gain for the years ended December 31, 2013 and 2011:


		Year ended December 31,
	(In thousands)	2013			2011
	Accumulated unrealized gain on available-for-sale securities at beginning of period	$	—		$	13
	Change during the period		(7	)		(13	)

	Accumulated unrealized loss on available-for-sale securities at end of period	$	(7	)	$	—

Fair Value of Each Option Award	'
	The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model. The following assumptions apply to the options to purchase 5,072,583, 187,500, and 1,671,000 shares of common stock granted to employees and directors during the years ended December 31, 2013, 2012 and 2011, respectively:


		2013			2012			2011
	Average risk free interest rate		1.3	%		0.8	%		1.4	%
	Expected dividend yield		—			—			—
	Expected lives (years)		5			5.6			6.3
	Expected volatility		67	%		62	%		64	%
	Weighted average grant date fair value of options granted during the period (per share)	$	0.89		$	0.51		$	0.75
	Weighted average exercise price of options granted during the period (per share)	$	1.55		$	0.92		$	1.26
Assets and Liabilities Measured at Fair Value on a Recurring Basis	'
	The table below presents the assets and liabilities measured and recorded in the financial statements at fair value on a recurring basis at December 31, 2013 and 2012 categorized by the level of inputs used in the valuation of each asset and liability.


	(In thousands)	Total			Quoted Prices			Significant			Significant
					in Active			Other			Unobservable
					Markets			Observable			Inputs
					for Identical			Inputs			(Level 3)
					Assets or			(Level 2)
					Liabilities
					(Level 1)
	December 31, 2013
	Assets
	Money market funds	$	25,201		$	25,201		$	—		$	—
	Short-term investments – commercial paper		1,997			—			1,997			—
	Short-term investments – corporate bonds		1,128						1,128
	Long-term investments		6,189			—			6,189			—

	Total Assets	$	34,515		$	25,201		$	9,314		$	—

	Total Liabilities	$	—		$	—		$	—		$	—

	December 31, 2012
	Assets
	Money market funds	$	9,990		$	9,990		$	—		$	—

	Total Assets	$	9,990		$	9,990		$	—		$	—

	Total Liabilities	$	—		$	—		$	—		$	—
Assumptions and Other Inputs Used to Compute the Fair Value of the Warrant Liability	'
	The Company revalued the warrants at the end of each quarter using the Black-Scholes Model and recognized the change in the fair value of the warrants in the statements of operations and comprehensive loss as other income (expense). The following assumptions and other inputs were used to compute the fair value of the warrant liability as of the November 4, 2011 issuance date, December 31, 2011 and November 9, 2012 when it was transferred to stockholders’ equity, as explained below:


		November 4,			December 31,			November 9,
		2011			2011			2012
	Common stock price	$	1.92		$	1.05		$	0.7
	Expected warrant exercise price	$	1.46		$	1.46		$	1.46
	Remaining term of warrant (years)		5			4.8			4
	Expected volatility		61	%		58	%		59	%
	Average risk free interest rate		0.9	%		0.8	%		0.5	%
	Expected dividend yield		—			—			—
	Expected percentage of warrants to be exercised		100	%		100	%		100	%
Changes in the Warrant Liability	'
	Changes in the warrant liability from November 4, 2011 to November 9, 2012 were as follows:


	(In thousands)	Fair Value of
	(In thousands)	Warrant Liability
	Balance, November 4, 2011	$	3,152
	Decrease in fair value		(1,974	)

	Balance, December 31, 2011		1,178
	Decrease in fair value		(675	)
	Transfer to stockholders’ equity		(503	)

	Balance, November 9, 2012	$	—

Investments_Tables

Investments (Tables)	12 Months Ended
Investments (Tables)	Dec. 31, 2013
Investments Debt And Equity Securities [Abstract]	'
Summary of Available-for-Sale Investments at Fair Value	'
	The Company’s available-for-sale investments at fair value consisted of the following at December 31, 2013:


		December 31, 2013
		Cost		Gross			Gross		Estimated
				Unrealized			Unrealized		Fair Value
				(Losses)			Gains
		(In thousands)
	Commercial paper due in one year or less	$	1,997	$	—		$	—	$	1,997
	Corporate bonds due in one year or less		1,128		—			—		1,128

	Total short-term investments		3,125		—			—		3,125
	Corporate bonds due in one year or more		6,196		(7	)		—		6,189

	Total long-term investments		6,196		(7	)		—		6,189

	Total investments	$	9,321	$	(7	)	$	—	$	9,314

Property_and_Equipment_Tables

Property and Equipment (Tables)	12 Months Ended
Property and Equipment (Tables)	Dec. 31, 2013
Property Plant And Equipment [Abstract]	'
Tabular Disclosure of Major Components of Property and Equipment and Related Accumulated Depreciation	'
	At December 31, 2013 and 2012, net property and equipment at cost consisted of the following:


		December 31,
		2013		2012
		(In thousands)
	Leasehold improvements	$	525	$	525
	Laboratory equipment and other		2,854		2,856

	Total property and equipment, at cost		3,379		3,381
	Less: Accumulated depreciation and amortization		3,289		3,163

	Property and equipment, net	$	90	$	218

Accrued_Expenses_Tables

Accrued Expenses (Tables)	12 Months Ended
Accrued Expenses (Tables)	Dec. 31, 2013
Payables And Accruals [Abstract]	'
Accrued Expenses	'
	At December 31, 2013 and 2012, accrued expenses consisted of the following:


		December 31,
		2013		2012
		(In thousands)
	Payroll and related costs	$	817	$	199
	Clinical and nonclinical trial expenses		1,277		895
	Cost of regaining rights to cancer program		966		1,309
	Professional and consulting fees		337		344
	Other		109		255

		$	3,506	$	3,002

Series_D_Redeemable_Convertibl1

Series D Redeemable Convertible Preferred Stock and Warrants (Tables)	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Summary of the Changes in the Series D Preferred Stock	'
	The following is a summary of the changes in the Series D preferred stock during 2012 and 2011 (in thousands):


	Gross proceeds from November 4, 2011 Series D financing (including $351 paid for the warrants)	$	9,500
	Less — allocation of proceeds to:
	fair value of warrants		(3,152	)
	beneficial conversion feature		(4,445	)
	transaction costs		(427	)

	Net proceeds allocated to Series D preferred stock		1,476
	Accretion of beneficial conversion feature		4,445

	Fair value of Series D preferred stock — November 4, 2011	$	5,921

	Fair value of Series D preferred stock — December 31, 2011	$	5,921
	Beneficial conversion feature related to Series E financing		(1,238	)
	Accretion of beneficial conversion feature		1,238

	Fair value of Series D preferred stock — December 31, 2012	$	5,921

Nonredeemable_Preferred_Stock_1

Non-redeemable Preferred Stock, Common Stock and Other Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Warrants Outstanding and Exercisable for the Purchase of Common Stock	'
	The Company has the following warrants outstanding and exercisable for the purchase of common stock at December 31, 2013:


	Expiration Date	Shares			Weighted
					Average Exercise
					Price Per share
	June 1, 2014		1,000,000		$	0.79
	August 5, 2015		1,628,402			3.71
	November 4, 2016		2,810,650			1.46
	November 9, 2017		8,484,840			0.7
	May 7, 2018		27,156,327			0.48
	May 7, 2020		15,816,327			0.01
	September 30, 2020		4,175,975			0.01

	Total		61,072,521			0.49

Summary of Stock Options	'
	The following table summarizes information related to the outstanding and exercisable options during 2013 (in thousands, except per share amounts and years):

		Stock			Weighted-Average		Weighted-Average		Aggregate
		Options			Exercise Price		Remaining		Intrinsic
							Contractual Life		Value
							(in years)
	Outstanding at December 31, 2012		5,656		$	4.96
	Granted		5,073			1.55
	Exercised		(171	)		1.16
	Forfeited		(189	)		1.16
	Expired		(221	)		5.24

	Outstanding at December 31, 2013		10,148			3.38		7.54	$	21,233

	Exercisable at December 31, 2013		4,530			5.64		5.18		3,982
	Total exercisable or expected to vest		9,850			3.44		7.48		20,319

Summary of the Changes in the Series E Preferred Stock	'
	The following is a summary of the changes in the Series E preferred stock during 2012 (in thousands):


	Gross proceeds from November 9, 2012 Series E financing (including $1,061 paid for the warrants)	$	7,000
	Less — allocation of proceeds to:
	fair value allocated to warrants		(2,322	)
	beneficial conversion feature		(1,262	)
	transaction costs		(977	)

	Net proceeds allocated to Series E preferred stock		2,439
	Accretion of beneficial conversion feature		1,262

	Carrying Value of Series E preferred stock — November 9, 2012	$	3,701

	Carrying Value of Series E preferred stock — December 31, 2012	$	3,701

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Future Minimum Commitments Under Company Lease Agreement	'
	The lease is classified as an operating lease. Future minimum commitments as of December 31, 2013 under the Company’s lease agreement are approximately:


	December 31,	Operating
		Lease
		(In thousands)
	2014	$	628

		$	628

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
Income Taxes (Tables)	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Components of the Deferred Tax Assets	'
	As of December 31, 2013 and 2012, the components of the deferred tax assets are approximately as follows:


		2013			2012
		(In thousands)
	Operating loss carryforwards	$	68,500		$	61,717
	Tax credit carryforwards		9,376			8,455
	Other		5,078			4,935

			82,954			75,107
	Valuation allowance		(82,954	)		(75,107	)

		$	—		$	—

Difference Between the 34% U.S. Federal Corporate Tax Rate and the Company's Effective Tax Rate	'
	The difference between the 34% U.S. federal corporate tax rate and the Company’s effective tax rate is as follows for the years ended December 31, 2013, 2012 and 2011:


		2013			2012			2011
	Expected federal income tax rate		(34.0	)%		(34.0	)%		(34.0	)%
	Expiring credits and NOLs		0.2			116.3			66.3
	Change in valuation allowance		43.1			(76.6	)		(22.5	)
	Federal and state credits		(5.0	)		(0.6	)		(3.3	)
	State income taxes, net of federal benefit		(5.1	)		(5.2	)		(5.4	)
	Permanent differences		0.9			0.1			(1.0	)
	Other		(0.1	)		—			(0.1	)

	Effective tax rate		0	%		0	%		0	%

Supplemental_Disclosure_of_Cas1

Supplemental Disclosure of Cash Flow Information (Tables)	12 Months Ended
Supplemental Disclosure of Cash Flow Information (Tables)	Dec. 31, 2013
Supplemental Cash Flow Elements [Abstract]	'
Supplemental Disclosure of Cash Flow Information	'
	Supplemental disclosure of cash flow information for the periods presented is as follows:


		Year Ended December 31,
		2013		2012		2011
		(In thousands)
	Supplemental disclosure of non cash financing and investing activities:

	Extinguishment of Series D and Series E preferred stock and issuance of related warrants	$	5,921	$	—	$	—

	Accrued 2013 financing transaction costs paid in 2014	$	100	$	—	$	—

	Accretion of Series D redeemable preferred stock beneficial conversion feature	$	—	$	1,238	$	4,445

	Accretion of Series E preferred stock beneficial conversion feature	$	—	$	1,262	$	—

	Reclassification of Series D warrants from liabilities to stockholders’ equity	$	—	$	503	$	—

April_2013_Pillar_Agreements_T

April 2013 Pillar Agreements (Tables)	12 Months Ended
April 2013 Pillar Agreements (Tables)	Dec. 31, 2013
Text Block [Abstract]	'
Schedule of Assumptions and Other Inputs Used to Compute Fair Value of Agreement Warrants	'
	The Company used the Black-Scholes Model to compute the fair value of the Pillar Warrants as of the May 7, 2013 effective date on which the Pillar Warrants were issued based on the following assumptions and other inputs:


		Pillar I			Additional
		Warrants			Pillar
					Warrants
	Common stock price	$	0.57		$	0.57
	Warrant exercise price	$	0.61		$	0.79
	Term of warrant (years)		5			1.1
	Expected volatility		62	%		67	%
	Average risk free interest rate		0.8	%		0.1	%
	Expected dividend yield		—			—
	Expected percentage of warrants to be exercised		100	%		100	%

Financings_Tables

Financings (Tables)	12 Months Ended
Financings (Tables)	Dec. 31, 2013
Text Block [Abstract]	'
May 2013 Follow-on Underwritten Public Offering	'
	On May 7, 2013, the Company closed a follow-on underwritten public offering, in which it sold 17,500,000 shares of common stock, together with matching warrants to purchase up to 17,500,000 shares of common stock, and pre-funded warrants to purchase up to 15,816,327 shares of common stock, together with matching warrants to purchase up to 15,816,327 shares of common stock, for aggregate gross proceeds of $16.5 million as follows:


		Combined		Common		Pre-funded		Matching
		Price to the		Stock		Warrants		Warrants
		Public
		(per share of
		Common
		Stock)
	Common stock and matching warrants sold (shares)	$	0.5		17,500,000		—		17,500,000
	Pre-funded warrants and matching warrants sold (shares)	$	0.49		—		15,816,327		15,816,327

	Total (shares)				17,500,000		15,816,327		33,316,327

	Warrant exercise price (per share)		—		—	$	0.01	$	0.47
	Term of warrant (years)		—		—		7		5

Organization_Additional_Inform

Organization - Additional Information (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'	'
Accumulated deficit	($412,884)	($394,658)

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)

0 Months Ended

2 Months Ended

10 Months Ended

12 Months Ended

2 Months Ended

12 Months Ended

Nov. 09, 2012

Dec. 31, 2011

Nov. 09, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Nov. 04, 2011

Dec. 31, 2010

Jan. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2011

Segment

Performance Shares [Member]

Director [Member]

Employees [Member]

Minimum [Member]

Maximum [Member]

Condition

Accounting Policies [Line Items]

Period of maturities

'90 days

Held-to-maturity investments

Realized gains or losses from available-for-sale securities

Losses from Securities

Auction rate securities

Total restricted cash

311,000

Equipment depreciated over a period

'3 years

'5 years

Accumulated unrealized gain or loss on available-for-sale securities

-7,000

13,000

Number of operating segment

Stock options generally vest over

'3 years

'4 years

Stock options granted

5,073,000

697,500

Performance based stock options granted - vest upon goal achievement

174,375

Performance based stock options granted - time vest beginning upon goal achievement

523,125

Options to purchase shares vested immediately

80,213

Options to purchase shares began vesting

240,640

Number of specified performance conditions achieved

Recorded charges in statement of Operations

1,398,000

2,096,000

2,725,000

Option to purchase common stock granted to employees and directors

5,072,583

187,500

1,671,000

Fair value of options, vested

1,429,000

2,123,000

2,707,000

Unrecognized compensation cost related to nonvested stock-based compensation

4,543,000

Period for cost expected to be recognized

'3 years 4 months 24 days

Intrinsic value of options exercised

150,000

Options Exercised

171,000

Floor price

$1.46

Exercise price of the Warrants

0.49

1.63

1.46

1.63

Actual stock-price volatility period

'3 years

Expected dividend yield

0.00%

Maximum warrants holder ownership in company

19.99%

Fair value of the warrant liability

503,000

1,178,000

503,000

1,178,000

3,152,000

Recognition of gain in other income

675,000

-1,974,000

-675,000

1,974,000

Fair value of warrant liability transferred to stockholders' equity

$503,000

Summary_of_Significant_Account4

Summary of Significant Accounting Policies - Change in Accumulated Balance of the Component of Other Comprehensive Loss (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2011
Accounting Policies [Abstract]	'	'
Accumulated unrealized gain on available-for-sale securities at beginning of period	'	$13
Change during the period	-7	-13
Accumulated unrealized loss on available-for-sale securities at end of period	($7)	'

Summary_of_Significant_Account5

Summary of Significant Accounting Policies - Fair Value of Each Option Award (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Expected dividend yield	0.00%	'	'
Weighted average exercise price of options granted during the period (per share)	$1.55	'	'
Stock Options [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Average risk free interest rate	1.30%	0.80%	1.40%
Expected dividend yield	'	'	'
Expected lives (years)	'5 years	'5 years 7 months 6 days	'6 years 3 months 18 days
Expected volatility	67.00%	62.00%	64.00%
Weighted average grant date fair value of options granted during the period (per share)	$0.89	$0.51	$0.75
Weighted average exercise price of options granted during the period (per share)	$1.55	$0.92	$1.26

Summary_of_Significant_Account6

Summary of Significant Accounting Policies - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	$34,515	$9,990
Total Liabilities	'	'
Fair Value, Measurements, Recurring [Member] \| Money Market Fund [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	25,201	9,990
Fair Value, Measurements, Recurring [Member] \| Short Term Investments Commercial Paper [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	1,997	'
Fair Value, Measurements, Recurring [Member] \| Short Term Investments Corporate Bonds [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	1,128	'
Fair Value, Measurements, Recurring [Member] \| Long Term Investments [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	6,189	'
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	25,201	9,990
Total Liabilities	'	'
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member] \| Fair Value, Measurements, Recurring [Member] \| Money Market Fund [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	25,201	9,990
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member] \| Fair Value, Measurements, Recurring [Member] \| Short Term Investments Commercial Paper [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	'	'
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member] \| Fair Value, Measurements, Recurring [Member] \| Short Term Investments Corporate Bonds [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	'	'
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member] \| Fair Value, Measurements, Recurring [Member] \| Long Term Investments [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	'	'
Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	9,314	'
Total Liabilities	'	'
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value, Measurements, Recurring [Member] \| Money Market Fund [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	'	'
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value, Measurements, Recurring [Member] \| Short Term Investments Commercial Paper [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	1,997	'
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value, Measurements, Recurring [Member] \| Short Term Investments Corporate Bonds [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	1,128	'
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value, Measurements, Recurring [Member] \| Long Term Investments [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	6,189	'
Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	'	'
Total Liabilities	'	'
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value, Measurements, Recurring [Member] \| Money Market Fund [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	'	'
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value, Measurements, Recurring [Member] \| Short Term Investments Commercial Paper [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	'	'
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value, Measurements, Recurring [Member] \| Short Term Investments Corporate Bonds [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	'	'
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value, Measurements, Recurring [Member] \| Long Term Investments [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Total Assets	'	'

Summary_of_Significant_Account7

Summary of Significant Accounting Policies - Assumptions and Other Inputs Used to Compute the Fair Value of the Warrant Liability (Detail) (USD $)	0 Months Ended
	Nov. 09, 2012	Dec. 31, 2011	Nov. 04, 2011	Sep. 30, 2013
Accounting Policies [Abstract]	'	'	'	'
Common stock price	$0.70	$1.05	$1.92	$1.55
Expected warrant exercise price	$1.46	$1.46	$1.46	'
Remaining term of warrant (years)	'4 years	'4 years 9 months 18 days	'5 years	'
Expected volatility	59.00%	58.00%	61.00%	'
Average risk free interest rate	0.50%	0.80%	0.90%	'
Expected dividend yield	'	'	'	'
Expected percentage of warrants to be exercised	100.00%	100.00%	100.00%	'

Summary_of_Significant_Account8

Summary of Significant Accounting Policies - Changes in the Warrant Liability (Detail) (USD $)	0 Months Ended	2 Months Ended	10 Months Ended	12 Months Ended
	Nov. 09, 2012	Dec. 31, 2011	Nov. 09, 2012	Dec. 31, 2011
Accounting Policies [Abstract]	'	'	'	'
Opening Balance	'	$3,152,000	$1,178,000	'
Decrease in fair value	675,000	-1,974,000	-675,000	1,974,000
Amount Transfer to stockholders' equity	'	'	-503,000	'
Closing Balance	$503,000	$1,178,000	$503,000	$1,178,000

Investments_Summary_of_Availab

Investments - Summary of Available-for-Sale Investments at Fair Value (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost	$9,321	'
Gross Unrealized (Losses)	-7	'
Gross Unrealized Gains	'	'
Estimated Fair Value	9,314	0
Commercial Paper Due in One Year or Less [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost	1,997	'
Gross Unrealized (Losses)	'	'
Gross Unrealized Gains	'	'
Estimated Fair Value	1,997	'
Corporate Bonds Due in One Year or Less [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost	1,128	'
Gross Unrealized (Losses)	'	'
Gross Unrealized Gains	'	'
Estimated Fair Value	1,128	'
Total Short-term Investments [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost	3,125	'
Gross Unrealized (Losses)	'	'
Gross Unrealized Gains	'	'
Estimated Fair Value	3,125	'
Corporate Bonds Due in One Year or More [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost	6,196	'
Gross Unrealized (Losses)	-7	'
Gross Unrealized Gains	'	'
Estimated Fair Value	6,189	'
Total Long-term Investments [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost	6,196	'
Gross Unrealized (Losses)	-7	'
Gross Unrealized Gains	'	'
Estimated Fair Value	$6,189	'

Investments_Additional_Informa

Investments - Additional Information (Detail) (USD $)	12 Months Ended			36 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013
Investments Debt And Equity Securities [Abstract]	'	'	'	'
Investments	$9,314	$0	'	$9,314
Realized gains or losses from available-for-sale securities	0	0	0	0
Auction Rate Securities, Noncurrent	$0	$0	'	$0

Property_and_Equipment_Tabular

Property and Equipment - Tabular Disclosure of Major Components of Property and Equipment and Related Accumulated Depreciation (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Property Plant And Equipment [Abstract]	'	'
Leasehold improvements	$525	$525
Laboratory equipment and other	2,854	2,856
Total property and equipment, at cost	3,379	3,381
Less: Accumulated depreciation and amortization	3,289	3,163
Property and equipment, net	$90	$218

Property_and_Equipment_Additio

Property and Equipment - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property Plant And Equipment [Abstract]	'	'	'
Depreciation and amortization expense	$137	$251	$494

Accrued_Expenses_Accrued_Expen

Accrued Expenses - Accrued Expenses (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Payables And Accruals [Abstract]	'	'
Payroll and related costs	$817	$199
Clinical and nonclinical trial expenses	1,277	895
Cost of regaining rights to cancer program	966	1,309
Professional and consulting fees	337	344
Other	109	255
Total accrued expenses	$3,506	$3,002

Collaboration_and_License_Agre1

Collaboration and License Agreements - Additional Information (Detail)

0 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

180 Months Ended

7-May-13

Sep. 30, 2013

Dec. 31, 2013

Dec. 31, 2012

Nov. 09, 2012

Dec. 31, 2011

Nov. 04, 2011

Dec. 31, 2013

Dec. 31, 2006

Dec. 31, 2013

Dec. 31, 2010

Jun. 30, 2010

Feb. 29, 2008

Dec. 31, 2013

Nov. 30, 2011

Dec. 31, 2013

Dec. 31, 2001

Dec. 31, 2013

USD ($)

EUR (€)

USD ($)

December 31, 2013 Exchange Rate [Member]

Merck Sharp [Member]

Merck KGaA [Member]

Isis Pharmaceuticals [Member]

University of Massachusetts Medical Center [Member]

USD ($)

EUR (€)

USD ($)

November 30, 2011 Exchange Rate [Member]

December 31, 2013 Exchange Rate [Member]

USD ($)

Agreement

USD ($)

Installment

USD ($)

Agreement

Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]

License fee paid to company

$20,000,000

$40,000,000

Proceeds from the sale of common stock under stock purchase agreement

10,000,000

Common stock price

$1.55

$0.70

$1.05

$1.92

$5.50

Aggregate potential milestones to be received under collaboration - one

165,000,000

Aggregate potential milestones to be received under collaboration - two

260,000,000

Extended revenue recognition period

'2 years

Revenue recognition period

'4 years

Research collaboration agreement, period

'2 years

Cumulative milestone revenue recognized in relation to the initiation of clinical trials or the achievement of preclinical milestones

1,000,000

12,100,000

Shares of common stock issued under stock purchase agreement

1,818,182

License fee received after foreign currency exchange rate in effect by company

39,700,000

Period of upfront payment revenue recognition

'28 months

Aggregate payments under agreement excluding potential milestones

1,800,000

2,500,000

Number of monthly installments

Payments made to date under agreement using exchange rate

1,400,000

1,100,000

Amount agreed to pay by the company on achievement of milestones

1,000,000

1,400,000

Final monthly installment

Maximum reimbursement agreed by the company

1,800,000

2,400,000

Payable termination agreement reimbursement

700,000

1,000,000

Payment to company by Isis in cash

15,000,000

Common stock issued

857,143

Value of common stock received for granting license

17,300,000

Sublicense income received from Isis

300,000

Payment made by company under license agreement

700,000

1,800,000

Shares of common stock issued under license agreement

17,500,000

13,727,251

1,005,499

Sale of common stock issued, value

6,023,000

1,200,000

Number of other license agreements

Proceeds from license agreement

$1,500,000

Patent license expiration year

'2014

Number of other royalty-bearing license agreements

Series_D_Redeemable_Convertibl2

Series D Redeemable Convertible Preferred Stock and Warrants - Additional Information (Detail) (USD $)

0 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

Nov. 09, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2011

Nov. 30, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Nov. 04, 2011

Series D Preferred Stock [Member]

Minimum [Member]

Series D Convertible Redeemable Preferred Stock [Member]

Schedule Of Redeemable Convertible Preferred Stock [Line Items]

Annual percentage of dividend of preferred stock

8.00%

7.00%

Percentage of holding by affiliates upon which warrants may not be exercised

19.99%

Dividends payable

$160,000

$190,000

Series E preferred dividend rate

4.60%

Additional Series D dividend due to Series E dividend

2.20%

Series D preferred stock initial conversion price

$1.63

Original purchase price per share available at time of liquidation, dissolution, winding up

$8.14

Common shares issued upon conversion of Series D preferred stock after adjustment in conversion price

5.5736

Series D preferred stock conversion price adjusted

$1.46

Maximum beneficial ownership of Series D and affiliates at which dividends may be paid in shares

19.99%

Minimum percentage of series D preferred stock conversion price for redemption of stock

200.00%

Minimum number of trading days used to determine if Series D warrants may be redeemed

'20 days

Series D Redeemable convertible preferred stock, shares designated

1,124,000

Series D Redeemable convertible preferred stock, shares issued

1,124,000

Series D Redeemable convertible preferred stock, shares outstanding

1,124,000

Initial discount on Series D preferred stock resulting in BCF

4,445,000

Net financing proceeds initially allocated to the Series D preferred stock

1,476,000

Original fair value of series D preferred stock

5,921,000

Minimum conversion price of the Series D preferred stock

$1.46

Additional discount on Series D preferred stock resulting in additional BCF

1,238,000

Redemption value of series D preferred stock

9,149,000

Additional BCF and dividend accretion if redemption of Series D preferred stock becomes probable

3,228,000

Exercise price of the Warrants

0.49

1.63

1.46

1.63

Minimum closing price of common stock for redemption of Series D warrants

$6.51

Warrant redemption price per share

$0.01

Amount transfer Series D warrant fair value to stockholders' equity

$503,000

Series_D_Redeemable_Convertibl3

Series D Redeemable Convertible Preferred Stock and Warrants - Summary of the Changes in the Series D Preferred Stock (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Nov. 04, 2011
Schedule Of Redeemable Convertible Preferred Stock [Line Items]	'	'	'
Accretion of beneficial conversion feature	$675,000	$1,974,000	'
Fair value of preferred stock, Ending Balance	5,921,000	'	'
Series D Convertible Redeemable Preferred Stock [Member]	'	'	'
Schedule Of Redeemable Convertible Preferred Stock [Line Items]	'	'	'
Fair value of Series D preferred stock, Beginning Balance	5,921,000	'	5,921,000
Gross proceeds from Series D financing (including $351 paid for the warrants)	'	9,500,000	'
Beneficial conversion feature related to Series E financing	-1,238,000	'	'
Fair value of warrants	'	-3,152,000	'
Beneficial conversion feature	'	-4,445,000	'
Transaction costs	'	-427,000	'
Net proceeds allocated to Series D preferred stock	'	1,476,000	'
Accretion of beneficial conversion feature	1,238,000	4,445,000	'
Fair value of preferred stock, Ending Balance	$5,921,000	$5,921,000	$5,921,000

Series_D_Redeemable_Convertibl4

Series D Redeemable Convertible Preferred Stock and Warrants - Summary of the Changes in the Series D Preferred Stock (Parenthetical) (Detail) (Series D Convertible Redeemable Preferred Stock [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2011
Series D Convertible Redeemable Preferred Stock [Member]	'
Schedule Of Redeemable Convertible Preferred Stock [Line Items]	'
Aggregate purchase price of Series D warrants	$351

Non_redeemable_Preferred_Stock

Non - redeemable Preferred Stock, Common Stock and Other Stockholders' Equity - Additional Information (Detail) (USD $)

0 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

7-May-13

Sep. 30, 2013

Dec. 31, 2013

Dec. 31, 2012

Nov. 09, 2012

Dec. 31, 2013

5-May-98

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Nov. 30, 2012

Nov. 09, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Series E Warrant [Member]

Two Thousand Thirteen Stock Incentive Plan [Member]

Minimum [Member]

Maximum [Member]

Common Stock [Member]

Employee Stock Purchase Plan [Member]

Series E Preferred Stock [Member]

Series A Preferred Stock [Member]

Series D Preferred Stock [Member]

Two Thousand Thirteen Stock Incentive Plan [Member]

Minimum [Member]

Maximum [Member]

Series E Warrant [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Common stock and warrants sold

17,500,000

13,727,251

1,199,684

424,000

Sale price of common shares subject to the liquidation put

$16

Minimum closing sales price of common stock to issue termination notice to put holders

$32

Price exceeds on number of days

'20 days

Liquidation put shares no longer held by original holders

399,950

Shares held with put holders

35,780

Remaining shares of common stock subject to the liquidation put

763,954

Stock options, vesting period

'3 years

'4 years

Stock options, expiration period

'10 years

Common stock shares under stock purchase plan

4,000,000

500,000

Additional number of common shares

5,945,000

Maximum number of Common stock shares under stock purchase plan

1,500,000

Minimum option exercise price as a percentage of fair value of common stock

100.00%

Common stock options outstanding

10,148,000

5,656,000

Common shares available for grant

1,317,099

Common stock, shares outstanding

66,252,000

27,643,000

7,245,719

424,000

1,124,000

Minimum Percentage Voting Stock that Prevents Employee Stock Purchase Plan Participation

5.00%

Percentage of fair market value of common stock used as option price

85.00%

Percentage of employee's regular pay

1.00%

10.00%

Percentage of Market Value of Common Stock on Commencement of Offering Period

85.00%

Maximum % of employee base pay that may be used to purchase stock under Employee Stock Purchase Plan

15.00%

Common stock share issued

14,716

4,746

26,155

Preferred stock, shares authorized

5,000,000

Preferred stock, Par value

$0.01

Preferred stock, shares designated

424,000

1,500,000

1,124,260

Annual percentage of dividend of preferred stock

8.00%

4.60%

1.00%

Preferred stock, shares outstanding

424,000

1,000

1,124,000

Series A preferred stock liquidation preference per share

Series A Preferred stock conversion price per share

$34

Preferred stock, shares issued

424,242

424,000

1,000

1,124,000

Dividend payable

$119,000

$40,000

Preferred stock dividend rate percentage if shareholders approve

8.00%

Minimum number of shares of Series E preferred stock outstanding to maintain protective provisions

84,849

Percentage Series E shareholder consent needed to dilute protective provisions

51.00%

Series E preferred stock conversion price

$0.70

Purchase price of the Series E preferred stock

$14

Percentage of outstanding common stock

19.99%

Series E Preferred stock, convertible into common stock

Minimum number of trading days used to determine if Series E preferred stock may be redeemed

'20 days

Trading days of common stock

'30 days

Minimum percentage of Series E preferred stock conversion price for redemption of stock

400.00%

Series E warrants issued, shares

8,484,840

Fair value of Series E warrants

2,949,000

Fair value of warrants

2,322,000

Beneficial conversion feature

$1,262,000

Non_redeemable_Preferred_Stock1

Non - redeemable Preferred Stock, Common Stock and Other Stockholders' Equity - Warrants Outstanding and Exercisable for the Purchase of Common Stock (Detail)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013
	Dec. 31, 2013	Dec. 31, 2012	Class of Warrant One [Member]	Class of Warrant Two [Member]	Class of Warrant Three [Member]	Class of Warrant Four [Member]	Class of Warrant Five [Member]	Class of Warrant Six [Member]	Class of Warrant Seven [Member]
Class of Warrant or Right [Line Items]	'	'	'	'	'	'	'	'	'
Expiration Date	'	'	1-Jun-14	5-Aug-15	4-Nov-16	9-Nov-17	7-May-18	7-May-20	30-Sep-20
Shares	61,072,521	'	1,000,000	1,628,402	2,810,650	8,484,840	27,156,327	15,816,327	4,175,975
Exercise price of the Warrants	0.49	1.63	0.79	3.71	1.46	0.7	0.48	0.01	0.01

Non_redeemable_Preferred_Stock2

Non - redeemable Preferred Stock, Common Stock and Other Stockholders' Equity - Summary of Stock Options (Detail) (USD $)	12 Months Ended
Share data in Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Equity [Abstract]	'	'	'
Options, Outstanding, Beginning Balance	5,656	'	'
Granted	5,073	'	'
Exercised	-171	0	0
Forfeited	-189	'	'
Expired	-221	'	'
Options, Outstanding, Ending Balance	10,148	5,656	'
Exercisable, Ending Balance	4,530	'	'
Total exercisable or expected to vest	9,850	'	'
Weighted Average Exercise Price, Beginning Balance	$4.96	'	'
Granted, Weighted Average Exercise Price	$1.55	'	'
Exercised, Weighted Average Exercise Price	$1.16	'	'
Forfeited, Weighted Average Exercise Price	$1.16	'	'
Expired, Weighted Average Exercise Price	$5.24	'	'
Weighted Average Exercise Price, Ending Balance	$3.38	$4.96	'
Exercisable, Weighted Average Exercise Price	$5.64	'	'
Total exercisable or expected to vest, Weighted Average Exercise Price	$3.44	'	'
Outstanding, Ending balance, Weighted Average Remaining Contractual Term	'7 years 6 months 15 days	'	'
Exercisable Ending Balance, Weighted Average Remaining Contractual Term	'5 years 2 months 5 days	'	'
Total exercisable or expected to vest, Weighted Average Remaining Contractual Term	'7 years 5 months 23 days	'	'
Outstanding, Intrinsic Value, Ending Balance	$21,233	'	'
Exercisable, Ending Balance, Intrinsic Value	3,982	'	'
Total exercisable or expected to vest, Aggregate Intrinsic Value	$20,319	'	'

Non_redeemable_Preferred_Stock3

Non - redeemable Preferred Stock, Common Stock and Other Stockholders' Equity - Summary of the Changes in the Series E Preferred Stock (Detail) (Series E Preferred Stock [Member], USD $)	1 Months Ended	12 Months Ended
	Nov. 09, 2012	Dec. 31, 2012
Series E Preferred Stock [Member]	'	'
Changes In Equity And Comprehensive Income Line Items [Line Items]	'	'
Gross proceeds from November 9, 2012 Series E financing (including $1,061 paid for the warrants)	'	$7,000,000
Fair value allocated to warrants	'	-2,322,000
Beneficial conversion feature	-1,262,000	-1,262,000
Transaction costs	'	-977,000
Net proceeds allocated to Series E preferred stock	'	2,439,000
Accretion of beneficial conversion feature	'	1,262,000
Carrying Value of Series E preferred stock	$3,701,000	$3,701,000

Non_redeemable_Preferred_Stock4

Non - redeemable Preferred Stock, Common Stock and Other Stockholders' Equity - Summary of the Changes in the Series E Preferred Stock (Parenthetical) (Detail) (Series E Preferred Stock [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2012
Series E Preferred Stock [Member]	'
Changes In Equity And Comprehensive Income Line Items [Line Items]	'
Amount paid for warrants	$1,061

Commitments_and_Contingencies_1

Commitments and Contingencies - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended			0 Months Ended		0 Months Ended
	Nov. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	7-May-13	Mar. 07, 2013	Sep. 30, 2013
	Shareholder	Agreement			Pillar Three Entities [Member]	Pillar Three Entities [Member]	Pillar Four Entities [Member]
	Director
Contingencies And Commitments [Line Items]	'	'	'	'	'	'	'
Rent expense, including real estate taxes	'	$1,601,000	$1,596,000	$1,582,000	'	'	'
Cash restricted for a security deposit	'	311,000	'	'	'	'	'
Operating lease expiration date	'	31-Aug-17	'	'	'	'	'
2014	'	628,000	'	'	'	'	'
2015	'	1,517,000	'	'	'	'	'
2016	'	1,546,000	'	'	'	'	'
2017	'	1,043,000	'	'	'	'	'
Period of renewal option exercisable by the Company	'	'3 years	'	'	'	'	'
Number of license agreements	'	6	'	'	'	'	'
Annual minimum payments due, 2014	'	35,000	'	'	'	'	'
Annual minimum payments due, 2015	'	10,000	'	'	'	'	'
Annual minimum payments due, 2016	'	10,000	'	'	'	'	'
Future minimum commitments under agreement, 2014	'	571,000	'	'	'	'	'
Future minimum commitments under agreement, 2015	'	571,000	'	'	'	'	'
Future minimum commitments under agreement, 2016	'	457,000	'	'	'	'	'
Number of directors managing investment decision	2	'	'	'	'	'	'
Number of significant shareholder managing investment decision	1	'	'	'	'	'	'
Number of shares of common stock sold in financing	'	'	'	'	5,000,000	'	1,774,193
Warrant to purchase common stock	'	61,072,521	'	'	'	5,000,000	'
Exercise price of warrants	'	0.49	1.63	'	'	0.47	'
Aggregate purchase price	'	'	'	'	2,500,000	'	2,750,000
Directors consulting fees	'	'	1,000	32,000	'	'	'
Common stock in lieu of director board and committee fees	'	$26,000	$1,000	$38,000	'	'	'

Commitments_and_Contingencies_2

Commitments and Contingencies - Future Minimum Commitments Under Company Lease Agreement (Detail) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'
2014	$628
Total	$628

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax [Line Items]	'	'	'
Cumulative federal net operating loss carryforwards	$190,645,000	'	'
Amount available to reduce state taxable income	82,292,000	'	'
Operating loss carryforwards expiration year	'2033	'	'
Federal tax credit carryforwards	5,887,000	'	'
State tax credit carryforwards	5,286,000	'	'
Period over which NOL and tax credit carryforward limitations are applied	'1 year	'	'
Period of cumulative changes in ownership	'3 years	'	'
Cumulative changes in ownership	50.00%	'	'
Federal corporate tax rate	-34.00%	-34.00%	-34.00%
Unrecognized tax benefits from uncertain tax	0	0	'
Years not subject to income tax examination	'Tax examinations for years before 2010	'	'
Period over which material changes in unrecognized tax positions are not expected	'12 months	'	'
Effect of the change in the tax law	'	475,000	'
Federal [Member]	'	'	'
Income Tax [Line Items]	'	'	'
Tax credit carryforward expiration year	'2033	'	'
Deductions related to the exercise of stock options	1,942,000	'	'
State [Member]	'	'	'
Income Tax [Line Items]	'	'	'
Tax credit carryforward expiration year	'2028	'	'
Deductions related to the exercise of stock options	$73,000	'	'

Income_Taxes_Components_of_the

Income Taxes - Components of the Deferred Tax Assets (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]	'	'
Operating loss carryforwards	$68,500	$61,717
Tax credit carryforwards	9,376	8,455
Other	5,078	4,935
Deferred Tax Assets, Gross	82,954	75,107
Valuation allowance	-82,954	-75,107
Deferred Tax Assets, Net	'	'

Income_Taxes_Difference_Betwee

Income Taxes - Difference Between the 34% U.S. Federal Corporate Tax Rate and the Company's Effective Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]	'	'	'
Expected federal income tax rate	-34.00%	-34.00%	-34.00%
Expiring credits and NOLs	0.20%	116.30%	66.30%
Change in valuation allowance	43.10%	-76.60%	-22.50%
Federal and state credits	-5.00%	-0.60%	-3.30%
State income taxes, net of federal benefit	-5.10%	-5.20%	-5.40%
Permanent differences	0.90%	0.10%	-1.00%
Other	-0.10%	'	-0.10%
Effective tax rate	0.00%	0.00%	0.00%

Employee_Benefit_Plan_Addition

Employee Benefit Plan - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Compensation And Retirement Disclosure [Abstract]	'	'	'
Maximum employer match as a percentage of base pay	3.00%	'	'
Portion of the first 6% of employees' contributions	50.00%	'	'
Portion of the Employee's base salary that the Company matches	6.00%	'	'
Employer matching contributions to the plan	$83,000	$106,000	$132,000

Net_Loss_per_Common_Share_Appl1

Net Loss per Common Share Applicable to Common Stockholders - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'
Total antidilutive securities	85,974,000	33,332,000	'
Net loss per common share applicable to common stockholders, dividends payable on preferred stock shares	$2,866,000	$3,210,000	$4,548,000
Series D and E Preferred Stock [Member]	'	'	'
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'
Loss on extinguishment of convertible preferred stock	1,750,000	'	'
Series D Preferred Stock [Member]	'	'	'
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'
Net loss per common share applicable to common stockholders, dividends payable on preferred stock shares	756,000	670,000	'
Redeemable preferred stock accretion and dividends	'	1,238,000	'
Series E Preferred Stock [Member]	'	'	'
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'
Net loss per common share applicable to common stockholders, dividends payable on preferred stock shares	360,000	40,000	'
Redeemable preferred stock accretion and dividends	'	$1,262,000	'

Supplemental_Disclosure_of_Cas2

Supplemental Disclosure of Cash Flow Information - Supplemental Disclosure of Cash Flow Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Supplemental disclosure of non cash financing and investing activities:	'	'	'
Accrued 2013 financing transaction costs paid in 2014	$100	'	'
Series D Warrant [Member]	'	'	'
Supplemental disclosure of non cash financing and investing activities:	'	'	'
Reclassification of warrants from liabilities to stockholders' equity	'	503	'
Series D and E Preferred Stock [Member]	'	'	'
Supplemental disclosure of non cash financing and investing activities:	'	'	'
Extinguishment of Series D and Series E preferred stock and issuance of related warrants	5,921	'	'
Series D Convertible Redeemable Preferred Stock [Member]	'	'	'
Supplemental disclosure of non cash financing and investing activities:	'	'	'
Accretion of Series D redeemable preferred stock beneficial conversion feature	'	1,238	4,445
Series E Preferred Stock [Member]	'	'	'
Supplemental disclosure of non cash financing and investing activities:	'	'	'
Accretion of Series E preferred stock beneficial conversion feature	'	$1,262	'

April_2013_Pillar_Agreements_A

April 2013 Pillar Agreements - Additional Information (Detail) (USD $)

0 Months Ended

12 Months Ended

0 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

7-May-13

Dec. 31, 2013

Apr. 22, 2013

Apr. 30, 2013

Dec. 31, 2013

7-May-13

Dec. 31, 2012

Dec. 31, 2013

7-May-13

Dec. 31, 2013

Apr. 30, 2013

Minimum [Member]

Pillar I Warrants [Member]

Additional Pillar Warrants [Member]

Series E Preferred Stock [Member]

Series D Preferred Stock [Member]

Extinguishment Loss [Member]

April 2013 Pillar Agreements [Member]

Agreement

Series E Preferred Stock [Member]

Series D Preferred Stock [Member]

Minimum [Member]

Effects of Agreements [Line Items]

Number of agreements

Unaffiliated ownership % that would trigger the right to require the Company to repurchase stock

66.67%

Percentage of preferred stock holders who waived right to receive specified amount in liquidation

100.00%

Number of Shares of Common Stock Callable By Pillar Warrants

1,000,000

Class of Warrant or Right Exercise Price Per Share of Warrants or Rights

0.61

0.79

Minimum closing price to redeem the warrants

2.8

Final exercise date of warrant

1-Jun-14

Redemption price per share of warrants

0.01

Carrying value of preferred stock prior to extinguishment

$3,701,000

$5,921,000

Carrying value of preferred stock

5,528,000

3,701,000

5,464,000

Fair value of the Pillar Warrants in equity at May 7, 2013

380,000

Extinguishment loss which was immediately charged to net loss applicable to common stockholders

1,750,000

Increase in stockholders equity resulting from preferred stock extinguishment and warrant issuance

$5,921,000

Minimum period for determining expected volatility

'3 years

Ownership percentage at which affiliates may not exercise warrants

19.99%

April_2013_Pillar_Agreements_S

April 2013 Pillar Agreements - Schedule of Assumptions and Other Inputs Used to Compute Fair Value of Agreement Warrants (Detail) (USD $)	0 Months Ended						1 Months Ended
	Nov. 09, 2012	Dec. 31, 2011	Nov. 04, 2011	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012	7-May-13	7-May-13
	Nov. 09, 2012	Dec. 31, 2011	Nov. 04, 2011	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012	Pillar I Warrants [Member]	Additional Pillar Warrants [Member]
Assumptions used to compute fair value of Pillar warrants [Line Items]	'	'	'	'	'	'	'	'
Common stock price	$0.70	$1.05	$1.92	'	$1.55	'	$0.57	$0.57
Warrant exercise price	'	'	'	0.49	'	1.63	0.61	0.79
Term of warrant (years)	'4 years	'4 years 9 months 18 days	'5 years	'	'	'	'5 years	'1 year 1 month 6 days
Expected volatility	59.00%	58.00%	61.00%	'	'	'	62.00%	67.00%
Average risk free interest rate	0.50%	0.80%	0.90%	'	'	'	0.80%	0.10%
Expected dividend yield	'	'	'	'	'	'	'	'
Expected percentage of warrants to be exercised	100.00%	100.00%	100.00%	'	'	'	100.00%	100.00%

Financings_Additional_Informat

Financings - Additional Information (Detail) (USD $)

0 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

0 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

7-May-13

Sep. 30, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Nov. 09, 2012

Nov. 04, 2011

Dec. 31, 2011

Nov. 30, 2011

Nov. 30, 2012

Nov. 30, 2011

Sep. 30, 2013

7-May-13

Nov. 30, 2012

Dec. 31, 2013

Dec. 31, 2012

Nov. 09, 2012

Nov. 30, 2011

Dec. 31, 2013

Nov. 30, 2011

Maximum [Member]

Warrant [Member]

Series E Warrant [Member]

Series D Warrant [Member]

Pre-funded Warrants [Member]

Matching Warrants Two [Member]

Matching Warrants One [Member]

Series E Preferred Stock [Member]

Series D Convertible Redeemable Preferred Stock [Member]

Maximum [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Common stock sold

17,500,000

13,727,251

424,000

Shares of common stock that may be purchased upon exercise of the warrants

61,072,521

2,810,650

4,175,975

15,816,327

17,500,000

8,484,840

Gross proceeds from sale of common stock and warrants excluding the proceeds from exercise of the warrants, if any

$16,500,000

$27,700,000

Warrants Exercise price per share

0.49

1.63

0.01

1.63

Common Stock price per share

$1.55

$1.05

$0.70

$1.92

Sales price per share of prefunded warrants

$1.54

Pre-funded warrants Expiration Date

30-Sep-20

Estimated net proceeds from sale of common stock and warrants excluding the proceeds from exercise of the warrants, if any

14,500,000

25,700,000

Issuance of warrants to purchase common stock

17,500,000

Redemption price per share of warrants

0.01

Notice period to holder prior to redemption of warrants by Company

'30 days

Minimum trading days considered to redeem warrants

'20 days

Minimum closing price to redeem the warrants

2.8

Proceeds from exercise of warrants

3,365,000

Shares issued on exercise of warrants during the period

7,160,000

Aggregate purchase price of series E

7,000,000

Preferred stock, shares issued

424,242

424,000

424,242

1,124,260

Common stock conversion price

$0.70

Initial conversion price of preferred stock and exercise price of warrants

$0.70

$1.63

Class of warrant or right expiration date

9-Nov-17

Dividends payable in arrears to the holders of preferred stock

8.00%

4.60%

7.00%

Increased preferred dividend rate

8.00%

Net proceeds from issuance of preferred stock

6,000,000

9,100,000

Percentage of penalty

10.00%

Aggregate purchase price under agreement

$9,500,000

Convertible preferred stock shares upon conversion

5,621,300

6,266,175

Initial conversion price

$1.63

Adjusted conversion price per share

$1.46

Adjusted number of common stock to be issued upon conversion

5.5736

Financings_May_2013_Followon_U

Financings - May 2013 Follow-on Underwritten Public Offering (Detail) (USD $)

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2012

Nov. 09, 2012

Dec. 31, 2011

Nov. 04, 2011

7-May-13

Sep. 30, 2013

7-May-13

Common Stock [Member]

Common Stock and Matching Warrants Sold [Member]

Pre-funded Warrants and Matching Warrants Sold [Member]

Matching Warrants [Member]

Pre-funded Warrants [Member]

Common Stock [Member]

Common Stock and Matching Warrants Sold [Member]

Pre-funded Warrants and Matching Warrants Sold [Member]

Equity [Line Items]

Combined Price to the Public (per Share of Common Stock)

$1.55

$0.70

$1.05

$1.92

$0.50

$0.49

Number of shares of common stock sold in financing

17,500,000

Total (shares)

61,072,521

33,316,327

17,500,000

15,816,327

4,175,975

15,816,327

Warrant exercise price (per share)

0.49

1.63

0.47

0.01

Term of warrant (years)

'5 years

'7 years

2013_Annual_Meeting_of_Stockho1

2013 Annual Meeting of Stockholders - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Stockholder Equity [Line Items]	'	'
Shares of common stock authorized before the amendment	140,000,000	'
Common stock shares authorized	280,000,000	140,000,000
Percentage of holding by affiliates upon which warrants may not be exercised	19.99%	'
Minimum [Member]	'	'
Stockholder Equity [Line Items]	'	'
Percentage of holding by affiliates upon which warrants may not be exercised	19.99%	'
Series D and E Preferred Stock [Member]	'	'
Stockholder Equity [Line Items]	'	'
Voting power limit prior to shareholder approval	19.99%	'
Series D and Series E Voting Power Limit	19.99%	'
Series D Preferred Stock [Member]	'	'
Stockholder Equity [Line Items]	'	'
Beneficial Ownership of Series D and affiliates at which dividends may not be paid in voting shares	19.99%	'
Beneficial Ownership % (in the event that if was approved by stockholders) of Series D and affiliates at which dividends may not be paid in voting shares	35.00%	'
Percentage of holding by affiliates upon which holder might not convert shares	19.99%	'
Percentage of holding by affiliates in the event that if was approved by stockholders upon which holder might not convert preferred shares into common shares	35.00%	'

Subsequent_Events_Additional_I

Subsequent Events - Additional Information (Detail) (USD $)	0 Months Ended	1 Months Ended	12 Months Ended			0 Months Ended	2 Months Ended			0 Months Ended
	7-May-13	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Feb. 10, 2014	Feb. 28, 2014	Feb. 06, 2014	Dec. 31, 2013	Feb. 06, 2014	Jan. 10, 2014
						Subsequent Event [Member]	Subsequent Event [Member]	Subsequent Event [Member]	Series D Preferred Stock [Member]	Series D Preferred Stock [Member]	Series D Preferred Stock [Member]
										Subsequent Event [Member]	Subsequent Event [Member]
Subsequent Event [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Preferred stock, shares designated	'	'	'	'	'	'	'	'	1,124,260	'	1,124,260
Preferred stock, shares outstanding	'	'	'	'	'	'	'	'	1,124,000	'	1,124,260
Preferred stock, shares issued	'	'	'	'	'	'	'	'	1,124,000	'	1,124,260
Convertible preferred stock shares issued upon conversion	'	'	'	'	'	'	'	'	'	6,266,175	'
Number of shares of Series D preferred stock outstanding after conversion	'	'	'	'	'	'	'	0	'	'	'
Common stock sold, shares	17,500,000	13,727,251	'	'	'	7,867,438	'	'	'	'	'
Common stock sold, per share	'	'	'	'	'	$4	'	'	'	'	'
Warrants to purchase common stock	'	'	'	'	'	2,158,750	'	'	'	'	'
Warrants to purchase common stock, price per share	'	'	'	'	'	$3.99	'	'	'	'	'
Gross proceeds from common stock	'	'	'	'	'	$40,100,000	'	'	'	'	'
Warrant exercise price per share	'	'	'	'	'	$0.01	'	'	'	'	'
Expiration of warrants exercised	'	'	'	'	'	10-Feb-21	'	'	'	'	'
Net proceeds from offering	'	'	'	'	'	37,200,000	'	'	'	'	'
Proceeds from exercise of warrants	'	'	$3,365,000	'	'	'	$5,082,000	'	'	'	'
Shares issued on exercise of warrants during the period	'	'	7,160,000	0	0	'	1,893,802	'	'	'	'