Aceragen (ACGN) 10-Q 11 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015	Apr. 15, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Trading Symbol	IDRA
Entity Registrant Name	IDERA PHARMACEUTICALS, INC.
Entity Central Index Key	861838
Current Fiscal Year End Date	-19
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		117,875,318

Condensed_Balance_Sheets_Unaud

Condensed Balance Sheets (Unaudited) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$92,273	$19,971
Short-term investments	21,187	21,256
Prepaid expenses and other current assets	1,735	1,203
Total current assets	115,195	42,430
Long-term investments	3,417	7,344
Property and equipment, net	1,354	1,306
Restricted cash and other assets	344	346
Total assets	120,310	51,426
Current liabilities:
Accounts payable	2,064	2,458
Accrued expenses	3,901	4,460
Current portion of note payable	175	128
Total current liabilities	6,140	7,046
Note payable, net of current portion	700	742
Other liabilities	205	236
Total liabilities	7,045	8,024
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.01 par value, Authorized - 5,000 shares
Common stock, $0.001 par value, Authorized - 280,000 shares; Issued and outstanding - 117,864 and 94,829 shares at March 31, 2015 and December 31, 2014, respectively	118	95
Additional paid-in capital	577,153	494,850
Accumulated deficit	-464,007	-451,526
Accumulated other comprehensive gain (loss)	1	-17
Total stockholders' equity	113,265	43,402
Total liabilities and stockholders' equity	120,310	51,426
Series E Preferred Stock [Member]
Stockholders' equity:
Preferred stock, $0.01 par value	0	0
Series A Preferred Stock [Member]
Stockholders' equity:
Preferred stock, $0.01 par value	$0	$0

Condensed_Balance_Sheets_Unaud1

Condensed Balance Sheets (Unaudited) (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Preferred stock, par value	$0.01	$0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	280,000,000	280,000,000
Common stock, shares issued	117,864,000	94,829,000
Common stock, shares outstanding	117,864,000	94,829,000
Series E Preferred Stock [Member]
Preferred stock, par value		$0.01
Preferred stock, shares designated	0	424,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Series A Preferred Stock [Member]
Preferred stock, par value	$0.01	$0.01
Preferred stock, shares designated	1,500,000	1,500,000
Preferred stock, shares issued	1,000	1,000
Preferred stock, shares outstanding	1,000	1,000

Condensed_Statements_of_Operat

Condensed Statements of Operations and Comprehensive Loss (Unaudited) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Alliance revenue	$34	$3
Operating expenses:
Research and development	8,720	6,933
General and administrative	3,837	2,043
Total operating expenses	12,557	8,976
Loss from operations	-12,523	-8,973
Other income (expense):
Investment income, net	14	15
Foreign currency exchange gain (loss)	28	-3
Net loss	-12,481	-8,961
Preferred stock dividends		185
Net loss applicable to common stockholders	-12,481	-9,146
Basic and diluted net loss per common share applicable to common stockholders (Note 12)	($0.12)	($0.12)
Shares used in computing basic and diluted net loss per common share applicable to common stockholders	105,067	76,018
Net loss	-12,481	-8,961
Other comprehensive gain:
Unrealized gain on available-for-sale securities	18	11
Other comprehensive gain	18	11
Comprehensive loss	($12,463)	($8,950)

Condensed_Statements_of_Cash_F

Condensed Statements of Cash Flows (Unaudited) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Cash Flows from Operating Activities:
Net loss	($12,481)	($8,961)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	1,346	535
Depreciation and amortization expense	101	31
Amortization of investment premiums	86	46
Issuance of common stock for services rendered	19	14
Non-employee stock option expense	240	11
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	-532	-286
Accounts payable, accrued expenses, and other liabilities	-1,488	1,008
Net cash used in operating activities	-12,709	-7,602
Cash Flows from Investing Activities:
Purchases of available-for-sale securities	-3,674	-616
Maturities of available-for-sale securities	6,602
Sales of available-for-sale securities	999
Purchases of property and equipment	-105	-12
Net cash provided by (used in) investing activities	3,822	-628
Cash Flows from Financing Activities:
Proceeds from equity financings, net of issuance costs	81,070	37,378
Dividends paid		-345
Prior year financing transaction costs paid in current year		-100
Proceeds from exercise of common stock warrants and options and employee stock purchases	121	5,768
Payments on capital lease	-2	-1
Net cash provided by financing activities	81,189	42,700
Net increase in cash and cash equivalents	72,302	34,470
Cash and cash equivalents, beginning of period	19,971	26,278
Cash and cash equivalents, end of period	$92,273	$60,748

Organization

Organization	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Organization	(1) Organization
	Idera Pharmaceuticals, Inc. (“Idera” or the “Company”) is a clinical-stage biopharmaceutical company focused on the discovery, development and commercialization of novel therapeutics for oncology and rare diseases. The Company uses two distinct proprietary drug discovery technology platforms to design and develop drug candidates. The Company developed these platforms based on its scientific expertise and pioneering work with synthetic oligonucleotides as therapeutic agents. Using its Toll-like receptor (“TLR”) targeting technology, the Company designs synthetic oligonucleotide-based drug candidates to act by modulating the activity of specific TLRs. In addition, using its gene silencing oligonucleotide (“GSO”) technology, the Company is developing GSOs to turn off the messenger RNA (“mRNA”) associated with disease causing genes. The Company considers its GSO technology to be a third generation antisense technology that can potentially reduce the immunotoxicity and increase the potency of earlier generation antisense and RNA interference (“RNAi”) technologies.
	Idera is currently conducting a Phase 1/2 clinical trial of IMO-8400 in patients with Waldenström’s macroglobulinemia and Phase 1/2 clinical trial of IMO-8400 in patients with diffuse large B-cell lymphoma (“DLBCL”) who harbor the MYD88 L265P oncogenic mutation. The Company is planning to initiate clinical development of IMO-8400 for the treatment of rare diseases and has selected dermatomyositis and Duchenne muscular dystrophy (“DMD”) as the first non-cancer rare diseases for which it plans to develop IMO-8400. The Company believes it can develop and commercialize therapies on its own in these disease indications, which are characterized by small, well-defined patient populations with serious unmet medical needs.
	The Company is also advancing a second novel synthetic oligonucleotide antagonist of TLR7, TLR8 and TLR9, IMO-9200, as a drug candidate for potential use in selected autoimmune disease indications. The Company is conducting a Phase 1 clinical trial of IMO-9200 in healthy subjects.
	The Company is also developing its GSOs to specifically address challenges associated with earlier generation antisense and RNAi technologies. Although currently used technologies to silence RNA have demonstrated the ability to inhibit the expression of disease-associated proteins, the Company believes that to reach their full therapeutic potential, gene silencing technologies need to achieve an improved therapeutic index with efficient systemic delivery without using a delivery technology, reduced immunotoxicity and increased potency. The Company is currently undertaking an analysis of oncology and rare disease indications for development of drug candidates generated from its GSO technology. The Company is planning to conduct disease model studies and begin IND-enabling development programs in each of the first two disease indications selected for further development in its GSO program in the second half of 2015.
	At March 31, 2015, the Company had an accumulated deficit of $464,007,000. 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 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.

New_Accounting_Pronouncements_

New Accounting Pronouncements - Recently Issued	3 Months Ended
	Mar. 31, 2015
Accounting Changes and Error Corrections [Abstract]
New Accounting Pronouncements - Recently Issued	(2) New Accounting Pronouncements - Recently Issued
	In May 2014, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2014-09 – Revenue from Contracts with Customers (Topic 606). This ASU requires an entity to recognize revenue from the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In particular, this ASU addresses contracts with more than one performance obligation, as well as the accounting for some costs to obtain or fulfill a contract with a customer, and provides for additional disclosures with respect to revenues and cash flows arising from contracts with customers. This ASU will be effective for fiscal years beginning after December 15, 2016. Early adoption of this ASU is not permitted. The Company is currently evaluating the effect that the adoption of this ASU will have on its financial statements.
	In August 2014, the FASB issued ASU No. 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern, or ASU 2014-15. ASU 2014-15 amends FASB ASC 205-40 Presentation of Financial Statements – Going Concern, by providing guidance on determining when and how reporting entities must disclose going-concern uncertainties in their financial statements, including requiring management to perform interim and annual assessments of an entity’s ability to continue as a going concern within one year of the date of issuance of the entity’s financial statements and providing certain disclosures if there is substantial doubt about the entity’s ability to continue as a going concern. ASU 2014-15 will be effective for fiscal years beginning after December 15, 2016 and for interim periods thereafter. Early adoption of ASU 2014-15 is permitted. The Company is currently evaluating the effect that the adoption of ASU 2014-15 will have on its financial statements.

Unaudited_Interim_Financial_St

Unaudited Interim Financial Statements	3 Months Ended
	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Unaudited Interim Financial Statements	(3) Unaudited Interim Financial Statements
	The accompanying unaudited financial statements included herein have been prepared by the Company in accordance with United States Generally Accepted Accounting Principles (“U.S. GAAP”) for interim financial information and pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Accordingly, certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. In the opinion of management, all adjustments, consisting of normal recurring adjustments, and disclosures considered necessary for a fair presentation of interim period results have been included. Interim results for the three months ended March 31, 2015 are not necessarily indicative of results that may be expected for the year ended December 31, 2015. For further information, refer to the financial statements and footnotes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2014, which was filed with the SEC on March 12, 2015.

Financial_Instruments

Financial Instruments	3 Months Ended
	Mar. 31, 2015
Investments, All Other Investments [Abstract]
Financial Instruments	(4) 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 6, “Fair Value of Assets and Liabilities.” 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, receivables and a note payable. The estimated fair values of these financial instruments approximate their carrying values as of March 31, 2015 and December 31, 2014. As of March 31, 2015 and December 31, 2014, the Company did not have any derivatives, hedging instruments or other similar financial instruments except for the note issued under the Company’s loan and security agreement, which is discussed in Note 5(a) to the financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014, including put and call features which the Company determined are clearly and closely associated with the debt host and do not require bifurcation as a derivative liability, or the fair value of the feature is immaterial.

Cash_and_Cash_Equivalents

Cash and Cash Equivalents	3 Months Ended
	Mar. 31, 2015
Cash and Cash Equivalents [Abstract]
Cash and Cash Equivalents	(5) Cash and Cash Equivalents
	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 March 31, 2015 and December 31, 2014 consisted of cash and money market funds.

Fair_Value_of_Assets_and_Liabi

Fair Value of Assets and Liabilities	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value of Assets and Liabilities	(6) 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 March 31, 2015 and December 31, 2014 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)
	March 31, 2015
	Assets
	Money market funds	$	90,662	$	90,662	$	—	$	—
	Other cash equivalents – commercial paper		1,500		—		1,500		—
	Short-term investments – commercial paper		5,998		—		5,998		—
	Short-term investments – corporate bonds		12,034		—		12,034		—
	Short-term investments – municipal bonds		3,155		—		3,155		—
	Long-term investments – corporate bonds		3,015		—		3,015		—
	Long-term investments – municipal bonds		402		—		402		—
	Total Assets	$	116,766	$	90,662	$	26,104	$	—
	Total Liabilities	$	—	$	—	$	—	$	—
	December 31, 2014
	Assets
	Money market funds	$	17,156	$	17,156	$	—	$	—
	Other cash equivalents – commercial paper		2,500		—		2,500		—
	Short-term investments – commercial paper		4,494		—		4,494		—
	Short-term investments – certificate of deposit		500		—		500		—
	Short-term investments – corporate bonds		14,357		—		14,357		—
	Short-term investments – municipal bonds		1,905		—		1,905		—
	Long-term investments –corporate bonds		7,344		—		7,344		—
	Total Assets	$	48,256	$	17,156	$	31,100	$	—
	Total Liabilities	$	—	$	—	$	—	$	—
	The Level 1 assets consist of money market funds, which are actively traded daily. The Level 2 assets consist of corporate bond, commercial paper, certificate of deposit and municipal bond investments whose fair value may not represent actual transactions of identical securities. The fair value of corporate and municipal 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. The fair value of certificates of deposits approximates carrying value. 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 March 31, 2015 or December 31, 2014.

Investments

Investments	3 Months Ended
	Mar. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Investments	(7) Investments
	The Company’s available-for-sale investments at fair value consisted of the following at March 31, 2015 and December 31, 2014:
		March 31, 2015
		Cost		Gross			Gross		Estimated
				Unrealized			Unrealized		Fair
				(Losses)			Gains		Value
		(In thousands)
	Short-term investments – commercial paper	$	5,997	$	—		$	1	$	5,998
	Short-term investments – corporate bonds		12,033		—			1		12,034
	Short-term investments – municipal bonds		3,156		(1	)		—		3,155
	Total short-term investments		21,186		(1	)		2		21,187
	Long-term investments – corporate bonds		3,015		—			—		3,015
	Long-term investments – municipal bonds		402		—			—		402
	Total long-term investments		3,417		—			—		3,417
	Total investments	$	24,603	$	(1	)	$	2	$	24,604
		December 31, 2014
		Cost		Gross			Gross		Estimated
				Unrealized			Unrealized		Fair
				(Losses)			Gains		Value
		(In thousands)
	Short-term investments – commercial paper	$	4,493	$	—		$	1	$	4,494
	Short-term investments – certificate of deposit		500		—			—		500
	Short-term investments – corporate bonds		14,364		(7	)		—		14,357
	Short-term investments – municipal bonds		1,906		(1	)		—		1,905
	Total short-term investments		21,263		(8	)		1		21,256
	Long-term investments – corporate bonds		7,354		(10	)		—		7,344
	Total long-term investments		7,354		(10	)		—		7,344
	Total investments	$	28,617	$	(18	)	$	1	$	28,600
	The Company had no realized gains or losses from available-for-sale securities in the three months ended March 31, 2015 and 2014. There were no losses or other-than-temporary declines in value included in “Investment income, net” on the Company’s condensed statements of operations and comprehensive loss for any securities for the three months ended March 31, 2015 and 2014. The Company had no auction rate securities as of March 31, 2015 and December 31, 2014. See Note 4, “Financial Instruments,” and Note 6, “Fair Value of Assets and Liabilities” for additional information related to the Company’s investments.

Property_and_Equipment

Property and Equipment	3 Months Ended
	Mar. 31, 2015
Property, Plant and Equipment [Abstract]
Property and Equipment	(8) Property and Equipment
	At March 31, 2015 and December 31, 2014, net property and equipment at cost consisted of the following:
	(In thousands)	March 31,		December 31,
		2015		2014
	Leasehold improvements	$	525	$	525
	Laboratory equipment and other		4,025		3,884
	Total property and equipment, at cost		4,550		4,409
	Less: accumulated depreciation		3,196		3,103
	Property and equipment, net	$	1,354	$	1,306
	Depreciation and amortization expense on property and equipment was approximately $93,000 and $31,000 in the three months ended March 31, 2015 and 2014, respectively.

Restricted_Cash

Restricted Cash	3 Months Ended
	Mar. 31, 2015
Cash and Cash Equivalents [Abstract]
Restricted Cash	(9) 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 March 31, 2015 and December 31, 2014, the restricted cash amounted to $311,000 held in certificates of deposit securing a line of credit for the lessor.

Comprehensive_Loss

Comprehensive (Loss)	3 Months Ended
	Mar. 31, 2015
Equity [Abstract]
Comprehensive (Loss)	(10) Comprehensive (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 loss for the three months ended March 31, 2015 and 2014 is comprised of reported net loss and any change in net unrealized gains and losses on investments during each period, which is included in accumulated other comprehensive gain (loss) 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 gain (loss) for the three months ended March 31, 2015 and 2014:
	(In thousands)	Three Months			Three Months
		ended March			ended March
		31, 2015			31, 2014
	Accumulated unrealized loss on available-for-sale securities at beginning of period	$	(17	)	$	(7	)
	Change during the period		18			11
	Accumulated unrealized gain on available-for-sale securities at end of period	$	1		$	4

StockBased_Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	(11) Stock-Based Compensation
	The Company recognizes all stock-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.
	The Company recorded charges of $1,346,000 and $535,000 in its statements of operations and comprehensive loss for the three months ended March 31, 2015 and 2014, respectively, for stock-based compensation expense attributable to stock-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 969,500 and 992,500 shares of common stock granted to employees and directors during the three months ended March 31, 2015 and 2014, respectively:
		Three Months Ended
		March 31,
		2015			2014
	Average risk free interest rate		1.2	%		1.6	%
	Expected dividend yield		—			—
	Expected lives (years)		4.2			5
	Expected volatility		92	%		81	%
	Weighted average grant date fair value of options granted during the period (per share)	$	2.98		$	3.36
	Weighted average exercise price of options granted during the period (per share)	$	4.5		$	5.15
	The expected lives and the expected volatility of the options granted during the three months ended March 31, 2015 and 2014 are based on historical experience. All options granted during the three months ended March 31, 2015 and 2014 were granted at exercise prices equal to the fair market value of the common stock on the dates of grant.

Net_Loss_per_Common_Share_Appl

Net Loss per Common Share Applicable to Common Stockholders	3 Months Ended
	Mar. 31, 2015
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 three months ended March 31, 2015 and 2014, 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 74,950,998 and 80,345,651 for the three months ended March 31, 2015 and 2014, respectively, and consist of stock options, preferred stock and warrants.
	For the three months ended March 31, 2014, net loss per common share applicable to common stockholders reflects $185,000 in dividends accrued on shares of the Company’s Series D convertible preferred stock (“Series D preferred stock”) and Series E convertible preferred stock (“Series E preferred stock”). There were no dividends accrued on the Series D preferred stock and Series E preferred stock during the three months ended March 31, 2015 because the Series D preferred stock and Series E preferred stock were converted to common stock during February 2014 and December 2014, respectively.

Common_Stock_Warrant_and_Optio

Common Stock Warrant and Option Exercises and Employee Stock Purchases	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Common Stock Warrant and Option Exercises and Employee Stock Purchases	(13) Common Stock Warrant and Option Exercises and Employee Stock Purchases
	During the three months ended March 31, 2015, the Company issued 30,806 shares of common stock in connection with employee stock purchases under the Company’s 1995 Employee Stock Purchase Plan (the “ESPP”) and stock option exercises, which resulted in total proceeds to the Company of $121,000.
	During the three months ended March 31, 2014, the Company issued 2,050,578 shares of common stock in connection with purchases under the ESPP and warrant and stock option exercises, which resulted in total proceeds to the Company of $5,768,000.

Related_Party_Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2015
Related Party Transactions [Abstract]
Related Party Transactions	(14) Related Party Transactions
	February 2014 Conversion of Series D Preferred Stock
	On January 10, 2014, the Company notified Pillar Pharmaceuticals I, L.P. (“Pillar I”), an investment partnership managed by one of the Company’s directors and significant stockholders and the holder of all 1,124,260 shares of the Company’s 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 Certificate of Designations, Preferences and Rights of Series D Preferred Stock (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.
	On March 28, 2014, the Company filed a Certificate of Elimination of Number of Shares of Preferred Stock Designated as Series D Convertible Preferred Stock with the State of Delaware Secretary of State which eliminated the designation of the shares of Series D preferred stock.
	December 2014 Conversion of Series E Preferred Stock
	In December 2014, the holders of Series E preferred stock converted such shares into 8,484,840 shares of common stock in accordance with the terms of the Certificate of Designations, Preferences and Rights of Series E Preferred Stock. As a result of this conversion, no shares of Series E preferred stock remain outstanding.
	On March 12, 2015, the Company filed a Certificate of Elimination of Number of Shares of Preferred Stock Designated as Series E Convertible Preferred Stock with the State of Delaware Secretary of State which eliminated the designation of the shares of Series E preferred stock.
	Director Stock Purchases
	The Company issued 3,927 and 2,855 shares of common stock in lieu of director board and committee fees of approximately $19,000 and $14,000 pursuant to the Company’s director compensation program during the three months ended March 31, 2015 and 2014, respectively.
	See also Note 15, “Registration Rights Agreement,” and Note 16, “Financing” for additional information on related party transactions.

Registration_Rights_Agreement

Registration Rights Agreement	3 Months Ended
	Mar. 31, 2015
Equity [Abstract]
Registration Rights Agreement	(15) Registration Rights Agreement
	On February 9, 2015, the Company entered into a registration rights agreement with investment funds (the “Selling Stockholders”) affiliated with Baker Bros. Advisors LP and two members of the Company’s board of directors, relating to the registration for resale of the shares of the Company’s common stock held by the Selling Stockholders, including the shares of the Company’s common stock that may be issued upon the exercise of warrants held by the Selling Stockholders (collectively, the “Registrable Shares”).
	Under the registration rights agreement, the Company has agreed to file a registration statement on Form S-3 with the SEC within 60 days after demand by any of the Selling Stockholders, to register for resale the Registrable Shares. The Company has agreed to use its reasonable best efforts to cause the registration statement to become effective as promptly as practicable after filing, and to remain effective until the shares being registered thereunder have been sold or may be sold freely without limitations or restrictions as to volume or manner of sale pursuant to Rule 144. The registration rights agreement contains customary covenants and agreements by the Company and customary indemnification obligations of the Company and the Selling Stockholders.

Financing

Financing	3 Months Ended
	Mar. 31, 2015
Disclosure Text Block Supplement [Abstract]
Financing	(16) Financing
	February 19, 2015 Follow-on Underwritten Public Offering
	On February 19, 2015, the Company closed a follow-on underwritten public offering, in which it sold 23,000,000 shares of common stock at a price to the public of $3.75 per share for aggregate gross proceeds of $86.3 million. The estimated net proceeds to the Company from the offering, after deducting underwriters’ discounts and commissions and other offering costs and expenses were approximately $80.6 million. Investment funds affiliated with Baker Bros. Advisors LP and two members of the Company’s board of directors purchased 5,333,333 shares in this offering at the $3.75 per share purchase price.
	On February 19, 2015, Baker Bros. Advisors LP and certain of its affiliated funds (which include the Selling Stockholders) (collectively, “Baker Brothers”) held 6,965,432 shares of the Company’s common stock, warrants to purchase up to 20,316,327 shares of the Company’s common stock at an exercise price of $0.47 per share and pre-funded warrants to purchase up to 22,151,052 shares of the Company’s common stock at an exercise price of $0.01 per share.
	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 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 pre-funded warrants, if any, were approximately $37.2 million.

Subsequent_Events

Subsequent Events	3 Months Ended
	Mar. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	(17) Subsequent Events
	The Company considers events or transactions that occur after the balance sheet date but prior to the issuance of the financial statements to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure.
	On April 1, 2015, the Company entered into a lease of approximately 4,300 square feet of office space in Exton, Pennsylvania through April 30, 2020, with one five-year renewal option exercisable by the Company. The lease is classified as an operating lease. Future minimum commitments as of April 1, 2015 under the Company’s Exton office lease agreement are approximately:
	December 31,	Operating
		Lease
		(In thousands)
	2015	$	50
	2016		76
	2017		78
	2018		81
	2019		83
	2020		28
		$	396

New_Accounting_Pronouncements_1

New Accounting Pronouncements - Recently Issued (Policies)	3 Months Ended
	Mar. 31, 2015
Accounting Changes and Error Corrections [Abstract]
New Accounting Pronouncements - Recently Issued	In May 2014, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2014-09 — Revenue from Contracts with Customers (Topic 606). This ASU requires an entity to recognize revenue from the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In particular, this ASU addresses contracts with more than one performance obligation, as well as the accounting for some costs to obtain or fulfill a contract with a customer, and provides for additional disclosures with respect to revenues and cash flows arising from contracts with customers. This ASU will be effective for fiscal years beginning after December 15, 2016. Early adoption of this ASU is not permitted. The Company is currently evaluating the effect that the adoption of this ASU will have on its financial statements.
	In August 2014, the FASB issued ASU No. 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern, or ASU 2014-15. ASU 2014-15 amends FASB ASC 205-40 Presentation of Financial Statements – Going Concern, by providing guidance on determining when and how reporting entities must disclose going-concern uncertainties in their financial statements, including requiring management to perform interim and annual assessments of an entity’s ability to continue as a going concern within one year of the date of issuance of the entity’s financial statements and providing certain disclosures if there is substantial doubt about the entity’s ability to continue as a going concern. ASU 2014-15 will be effective for fiscal years beginning after December 15, 2016 and for interim periods thereafter. Early adoption of ASU 2014-15 is permitted. The Company is currently evaluating the effect that the adoption of ASU 2014-15 will have on its financial statements.

Fair_Value_of_Assets_and_Liabi1

Fair Value of Assets and Liabilities (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
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 March 31, 2015 and December 31, 2014 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)
	March 31, 2015
	Assets
	Money market funds	$	90,662	$	90,662	$	—	$	—
	Other cash equivalents – commercial paper		1,500		—		1,500		—
	Short-term investments – commercial paper		5,998		—		5,998		—
	Short-term investments – corporate bonds		12,034		—		12,034		—
	Short-term investments – municipal bonds		3,155		—		3,155		—
	Long-term investments – corporate bonds		3,015		—		3,015		—
	Long-term investments – municipal bonds		402		—		402		—
	Total Assets	$	116,766	$	90,662	$	26,104	$	—
	Total Liabilities	$	—	$	—	$	—	$	—
	December 31, 2014
	Assets
	Money market funds	$	17,156	$	17,156	$	—	$	—
	Other cash equivalents – commercial paper		2,500		—		2,500		—
	Short-term investments – commercial paper		4,494		—		4,494		—
	Short-term investments – certificate of deposit		500		—		500		—
	Short-term investments – corporate bonds		14,357		—		14,357		—
	Short-term investments – municipal bonds		1,905		—		1,905		—
	Long-term investments –corporate bonds		7,344		—		7,344		—
	Total Assets	$	48,256	$	17,156	$	31,100	$	—
	Total Liabilities	$	—	$	—	$	—	$	—

Investments_Tables

Investments (Tables)	3 Months Ended
	Mar. 31, 2015
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 March 31, 2015 and December 31, 2014:
		March 31, 2015
		Cost		Gross			Gross		Estimated
				Unrealized			Unrealized		Fair
				(Losses)			Gains		Value
		(In thousands)
	Short-term investments – commercial paper	$	5,997	$	—		$	1	$	5,998
	Short-term investments – corporate bonds		12,033		—			1		12,034
	Short-term investments – municipal bonds		3,156		(1	)		—		3,155
	Total short-term investments		21,186		(1	)		2		21,187
	Long-term investments – corporate bonds		3,015		—			—		3,015
	Long-term investments – municipal bonds		402		—			—		402
	Total long-term investments		3,417		—			—		3,417
	Total investments	$	24,603	$	(1	)	$	2	$	24,604
		December 31, 2014
		Cost		Gross			Gross		Estimated
				Unrealized			Unrealized		Fair
				(Losses)			Gains		Value
		(In thousands)
	Short-term investments – commercial paper	$	4,493	$	—		$	1	$	4,494
	Short-term investments – certificate of deposit		500		—			—		500
	Short-term investments – corporate bonds		14,364		(7	)		—		14,357
	Short-term investments – municipal bonds		1,906		(1	)		—		1,905
	Total short-term investments		21,263		(8	)		1		21,256
	Long-term investments – corporate bonds		7,354		(10	)		—		7,344
	Total long-term investments		7,354		(10	)		—		7,344
	Total investments	$	28,617	$	(18	)	$	1	$	28,600

Property_and_Equipment_Tables

Property and Equipment (Tables)	3 Months Ended
	Mar. 31, 2015
Property, Plant and Equipment [Abstract]
Tabular Disclosure of Major Components of Property and Equipment and Related Accumulated Depreciation	At March 31, 2015 and December 31, 2014, net property and equipment at cost consisted of the following:
	(In thousands)	March 31,		December 31,
		2015		2014
	Leasehold improvements	$	525	$	525
	Laboratory equipment and other		4,025		3,884
	Total property and equipment, at cost		4,550		4,409
	Less: accumulated depreciation		3,196		3,103
	Property and equipment, net	$	1,354	$	1,306

Comprehensive_Loss_Tables

Comprehensive (Loss) (Tables)	3 Months Ended
	Mar. 31, 2015
Equity [Abstract]
Changes in Accumulated Balance of the Component of Other Comprehensive Gain (Loss)	The following table includes the changes in the accumulated balance of the component of other comprehensive gain (loss) for the three months ended March 31, 2015 and 2014:
	(In thousands)	Three Months			Three Months
		ended			ended
		March 31,			March 31,
		2015			2014
	Accumulated unrealized loss on available-for-sale securities at beginning of period	$	(17	)	$	(7	)
	Change during the period		18			11
	Accumulated unrealized gain on available-for-sale securities at end of period	$	1		$	4

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Assumptions Used to Determine Fair Value of Stock Options Granted During Period	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 969,500 and 992,500 shares of common stock granted to employees and directors during the three months ended March 31, 2015 and 2014, respectively:
		Three Months Ended
		March 31,
		2015			2014
	Average risk free interest rate		1.2	%		1.6	%
	Expected dividend yield		—			—
	Expected lives (years)		4.2			5
	Expected volatility		92	%		81	%
	Weighted average grant date fair value of options granted during the period (per share)	$	2.98		$	3.36
	Weighted average exercise price of options granted during the period (per share)	$	4.5		$	5.15

Subsequent_Events_Tables

Subsequent Events (Tables)	3 Months Ended
	Mar. 31, 2015
Subsequent Events [Abstract]
Schedule of Future Minimum Commitments	Future minimum commitments as of April 1, 2015 under the Company’s Exton office lease agreement are approximately:
	December 31,	Operating
		Lease
		(In thousands)
	2015	$	50
	2016		76
	2017		78
	2018		81
	2019		83
	2020		28
		$	396

Organization_Additional_Inform

Organization - Additional Information (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
	Platform
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of technology platform to develop drug candidates	2
Accumulated deficit	($464,007)	($451,526)

Fair_Value_of_Assets_and_Liabi2

Fair Value of Assets and Liabilities - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) (Fair Value, Measurements, Recurring [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	$116,766	$48,256
Total Liabilities	0	0
Money Market Funds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	90,662	17,156
Commercial paper [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	1,500	2,500
Long-term Investments - Municipal Bonds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	402
Short-term Investments [Member] | Commercial Paper [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	5,998	4,494
Short-term Investments [Member] | Certificates of Deposit [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets		500
Short-term Investments [Member] | Corporate Bonds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	12,034	14,357
Short-term Investments [Member] | Municipal Bonds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	3,155	1,905
Long-term Investments - Corporate Bonds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	3,015	7,344
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	90,662	17,156
Total Liabilities	0	0
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member] | Money Market Funds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	90,662	17,156
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	26,104	31,100
Total Liabilities	0	0
Significant Other Observable Inputs (Level 2) [Member] | Commercial paper [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	1,500	2,500
Significant Other Observable Inputs (Level 2) [Member] | Long-term Investments - Municipal Bonds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	402
Significant Other Observable Inputs (Level 2) [Member] | Short-term Investments [Member] | Commercial Paper [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	5,998	4,494
Significant Other Observable Inputs (Level 2) [Member] | Short-term Investments [Member] | Certificates of Deposit [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets		500
Significant Other Observable Inputs (Level 2) [Member] | Short-term Investments [Member] | Corporate Bonds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	12,034	14,357
Significant Other Observable Inputs (Level 2) [Member] | Short-term Investments [Member] | Municipal Bonds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	3,155	1,905
Significant Other Observable Inputs (Level 2) [Member] | Long-term Investments - Corporate Bonds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Assets	3,015	7,344
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total Liabilities	$0	$0

Investments_Summary_of_Availab

Investments - Summary of Available-for-Sale Investments at Fair Value (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Cost	$24,603	$28,617
Gross Unrealized (Losses)	-1	-18
Gross Unrealized Gains	2	1
Estimated Fair Value	24,604	28,600
Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost	21,186	21,263
Gross Unrealized (Losses)	-1	-8
Gross Unrealized Gains	2	1
Estimated Fair Value	21,187	21,256
Short-term Investments [Member] | Commercial paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost	5,997	4,493
Gross Unrealized Gains	1	1
Estimated Fair Value	5,998	4,494
Short-term Investments [Member] | Corporate bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost	12,033	14,364
Gross Unrealized (Losses)		-7
Gross Unrealized Gains	1
Estimated Fair Value	12,034	14,357
Short-term Investments [Member] | Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost	3,156	1,906
Gross Unrealized (Losses)	-1	-1
Estimated Fair Value	3,155	1,905
Short-term Investments [Member] | Certificates of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost		500
Estimated Fair Value		500
Long-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost	3,417	7,354
Gross Unrealized (Losses)		-10
Estimated Fair Value	3,417	7,344
Long-term Investments [Member] | Corporate bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost	3,015	7,354
Gross Unrealized (Losses)		-10
Estimated Fair Value	3,015	7,344
Long-term Investments [Member] | Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost	402
Estimated Fair Value	$402

Investments_Additional_Informa

Investments - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Realized gains or losses from available-for-sale securities	$0	$0
Auction rate securities, noncurrent	0		0
Losses from investments	$0	$0

Property_and_Equipment_Tabular

Property and Equipment - Tabular Disclosure of Major Components of Property and Equipment and Related Accumulated Depreciation (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Property, Plant and Equipment [Abstract]
Leasehold improvements	$525	$525
Laboratory equipment and other	4,025	3,884
Total property and equipment, at cost	4,550	4,409
Less: accumulated depreciation	3,196	3,103
Property and equipment, net	$1,354	$1,306

Property_and_Equipment_Additio

Property and Equipment - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense on property and equipment	$93,000	$31,000

Restricted_Cash_Additional_Inf

Restricted Cash - Additional Information (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Restricted Cash [Abstract]
Total restricted cash	$311,000	$311,000

Comprehensive_Loss_Change_in_A

Comprehensive (Loss) - Change in Accumulated Balance of the Component of Other Comprehensive Gain (Loss) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Comprehensive Income (Loss) After Tax [Abstract]
Accumulated unrealized loss on available-for-sale securities at beginning of period	($17)	($7)
Change during the period	18	11
Accumulated unrealized gain on available-for-sale securities at end of period	$1	$4

StockBased_Compensation_Additi

Stock-Based Compensation - Additional Information (Detail) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recorded charges in statement of operations	$1,346	$535
Options to purchase common stock granted to employees and directors	969,500	992,500
Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period	4 years
Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period	3 years

StockBased_Compensation_Schedu

Stock-Based Compensation - Schedule of Assumptions Used to Determine Fair Value of Stock Options Granted During Period (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Average risk free interest rate	1.20%	1.60%
Expected dividend yield	0.00%	0.00%
Expected lives (years)	4 years 2 months 12 days	5 years
Expected volatility	92.00%	81.00%
Weighted average grant date fair value of options granted during the period (per share)	$2.98	$3.36
Weighted average exercise price of options granted during the period (per share)	$4.50	$5.15

Net_Loss_per_Common_Share_Appl1

Net Loss per Common Share Applicable to Common Stockholders - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Total antidilutive securities	74,950,998	80,345,651
Preferred stock dividends		$185,000
Series D and E Preferred Stock [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Preferred stock dividends	0	$185,000

Common_Stock_Warrant_and_Optio1

Common Stock Warrant and Option Exercises and Employee Stock Purchases - Additional Information (Detail) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Warrant and Option Exercises and Employee Stock Purchases [Line Items]
Proceeds from stock issued for warrant and option exercises & ESPP purchases	$121	$5,768
Common Stock Warrant and Option Exercises and Employee Stock Purchases [Member]
Warrant and Option Exercises and Employee Stock Purchases [Line Items]
Number of shares of common stock issued for stock warrant and stock options exercised and ESPP purchases	30,806	2,050,578
Proceeds from stock issued for warrant and option exercises & ESPP purchases	$121	$5,768

Related_Party_Transactions_Add

Related Party Transactions - Additional Information (Detail) (USD $)	3 Months Ended		0 Months Ended	1 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Feb. 06, 2014	Dec. 31, 2014	Jan. 10, 2014
Directors [Member]
Related Party Transaction [Line Items]
Common stock issued in lieu of board fees	3,927	2,855
Common stock issued	$19,000	$14,000
Series D Preferred Stock [Member]
Related Party Transaction [Line Items]
Preferred stock, shares issued					1,124,260
Preferred stock, shares outstanding			0		1,124,260
Shares of common stock issued upon conversion			6,266,175
Series E Preferred Stock [Member]
Related Party Transaction [Line Items]
Preferred stock, shares issued	0			0
Preferred stock, shares outstanding	0			0
Shares of common stock issued upon conversion				8,484,840

Registration_Rights_Agreement_

Registration Rights Agreement - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2015
Equity [Abstract]
Registration rights agreement date	9-Feb-15
Registration statement filing with SEC Period	60 days

Financing_Additional_Informati

Financing - Additional Information (Detail) (USD $)	0 Months Ended
In Millions, except Share data, unless otherwise specified	Feb. 19, 2015	Feb. 10, 2014
Class of Stock [Line Items]
Stock issued, shares	23,000,000
Common stock, price per share	$3.75
Gross proceeds from common stocks sold	$86.30
Estimated net proceeds from common stocks sold	80.6
Gross proceeds from sale of common stock and warrants excluding the proceeds from exercise of the warrants, if any		40.1
Sales price per share of pre-funded warrants		$3.99
Estimated net proceeds from sale of common stock and warrants excluding the proceeds from exercise of the warrants, if any		$37.20
Investment Funds [Member] | Directors [Member]
Class of Stock [Line Items]
Stock issued, shares	5,333,333
Common stock, price per share	$3.75
Baker Bros. Advisors LP [Member]
Class of Stock [Line Items]
Common stock held, shares	6,965,432
Shares of common stock that may be purchased upon exercise of warrants	20,316,327
Exercise price of warrants	$0.47
Common Stock [Member]
Class of Stock [Line Items]
Stock issued, shares		7,867,438
Price to the public per share of common stock		$4
Pre-funded Warrants [Member]
Class of Stock [Line Items]
Shares of common stock that may be purchased upon exercise of warrants		2,158,750
Exercise price of warrants		$0.01
Pre-funded warrants expiration date		10-Feb-21
Pre-funded Warrants [Member] | Baker Bros. Advisors LP [Member]
Class of Stock [Line Items]
Shares of common stock that may be purchased upon exercise of warrants	22,151,052
Exercise price of warrants	$0.01

Subsequent_Events_Additional_I

Subsequent Events - Additional Information (Detail) (Subsequent Events [Member], Exton [Member])	0 Months Ended
	Apr. 01, 2015
	sqft
Subsequent Events [Member] | Exton [Member]
Subsequent Event [Line Items]
Area of leased office space	4,300
Lease maturity date	30-Apr-20
Operating lease renewal term	5 years

Subsequent_Events_Schedule_of_

Subsequent Events - Schedule of Future Minimum Commitments (Detail) (Subsequent Events [Member], Exton [Member], USD $)	Apr. 01, 2015
In Thousands, unless otherwise specified
Subsequent Events [Member] | Exton [Member]
Operating Leases Future Minimum Payments Due [Line Items]
2015	$50
2016	76
2017	78
2018	81
2019	83
2020	28
Total	$396