Organovo (ONVO) 10-K10 Jun 142014 FY Annual reportFinancial data

Company Profile

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
Document and Entity Information (USD $)	Mar. 31, 2014	Jun. 06, 2014	Sep. 30, 2013
Document And Entity Information [Abstract]	'	'	'
Document Type	'10-K	'	'
Amendment Flag	'false	'	'
Document Period End Date	31-Mar-14	'	'
Document Fiscal Year Focus	'2014	'	'
Document Fiscal Period Focus	'FY	'	'
Trading Symbol	'ONVO	'	'
Entity Registrant Name	'ORGANOVO HOLDINGS, INC.	'	'
Entity Central Index Key	'0001497253	'	'
Current Fiscal Year End Date	'--03-31	'	'
Entity Well-known Seasoned Issuer	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Filer Category	'Accelerated Filer	'	'
Entity Common Stock, Shares Outstanding	'	78,276,250	'
Entity Public Float	'	'	$394,475,790

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
Current Assets	'	'	'
Cash and cash equivalents	$48,167	$15,628	$14,817
Grant receivable	'	101	162
Inventory	63	88	360
Deferred financing costs	40	'	'
Prepaid expenses and other current assets	891	327	527
Total current assets	49,161	16,144	15,866
Fixed assets, net	857	1,045	714
Restricted cash	79	88	88
Other assets, net	89	98	81
Total assets	50,186	17,375	16,749
Current Liabilities	'	'	'
Accounts payable	326	641	425
Accrued expenses	1,167	780	981
Deferred revenue	13	53	'
Current portion of capital lease obligation	10	10	10
Warrant liabilities	377	6,898	20,619
Total current liabilities	1,893	8,382	22,035
Deferred revenue, net of current portion	4	9	'
Capital lease obligation, net of current portion	5	15	17
Total liabilities	1,902	8,406	22,052
Commitments and Contingencies (Note 8)	'	'	'
Stockholders' Equity (Deficit)	'	'	'
Common stock, $0.001 par value; 150,000,000 shares authorized, 78,113,639, 64,686,919 and 58,535,411 shares issued and outstanding at March 31, 2014, March 31, 2013, and December 31, 2012, respectively	78	65	59
Additional paid-in capital	140,419	75,269	44,883
Deficit accumulated during the development stage	-92,213	-66,365	-50,245
Total stockholders' equity (deficit)	48,284	8,969	-5,303
Total Liabilities and Stockholders' Equity (Deficit)	$50,186	$17,375	$16,749

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
Statement Of Financial Position [Abstract]	'	'	'
Common stock, par value	$0.00	$0.00	$0.00
Common stock, shares authorized	150,000,000	150,000,000	150,000,000
Common stock, shares issued	78,113,639	64,686,919	58,535,411
Common stock, shares outstanding	78,113,639	64,686,919	58,535,411

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	3 Months Ended		12 Months Ended			83 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2011	Mar. 31, 2014
Revenues	'	'	'	'	'	'
Product	'	'	'	'	$224	$224
Collaborations	98	120	248	1,035	688	2,144
Grants	117	'	131	162	57	1,074
Total Revenues	215	120	379	1,197	969	3,442
Cost of product revenue	'	'	'	'	121	134
Selling, general, and administrative expenses	2,792	902	13,054	7,080	1,733	25,593
Research and development expenses	1,448	547	7,974	3,436	1,420	16,056
Loss from Operations	-4,025	-1,329	-20,649	-9,319	-2,305	-38,341
Other Income (Expense)	'	'	'	'	'	'
Fair value of warrant liabilities in excess of proceeds received	'	-19,019	'	-19,019	'	-19,019
Change in fair value of warrant liabilities	-12,034	-13,506	-5,120	-9,931	-7	-27,092
Financing transaction costs in excess of proceeds received	'	-2,130	'	-2,130	'	-2,130
Loss on inducement to exercise warrants	'	'	'	-1,904	'	-1,904
Loss on disposal of fixed assets	'	'	-84	-158	'	-242
Interest expense	-65	-1,088	-13	-1,088	-2,067	-3,484
Interest income	4	'	18	5	'	29
Other expense	'	-9	'	-9	-4	-30
Total Other Income (Expense)	-12,095	-35,752	-5,199	-34,234	-2,078	-53,872
Net Loss	($16,120)	($37,081)	($25,848)	($43,553)	($4,383)	($92,213)
Net loss per common share - basic and diluted	($0.26)	($1.17)	($0.35)	($1.01)	($0.19)	'
Weighted average shares used in computing net loss per common share - basic and diluted	61,750,157	31,591,663	73,139,618	43,149,657	22,925,694	'

Consolidated_Statements_of_Sto

Consolidated Statements of Stockholders' Equity (Deficit) (USD $)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Deficit Accumulated During the Development Stage [Member]
Beginning balance at Apr. 19, 2007	'	'	'	'
Issuance of common stock	'	'	'	'
Stock-based compensation expense	'	'	'	'
Net loss	'	'	'	'
Ending balance at Dec. 31, 2007	'	'	'	'
Ending balance, Shares at Dec. 31, 2007	'	'	'	'
Issuance of common stock to founders	'	2,000	-2,000	'
Issuance of common stock to founders, Shares	'	1,730,000	'	'
Issuance of restricted common stock	'	12,000	-12,000	'
Issuance of restricted common stock, Shares	'	12,628,000	'	'
Stock-based compensation expense	2,000	'	2,000	'
Net loss	-98,000	'	'	-98,000
Ending balance at Dec. 31, 2008	-96,000	14,000	-12,000	-98,000
Ending balance, Shares at Dec. 31, 2008	'	14,358,000	'	'
Issuance of restricted common stock, Shares	'	130,000	'	'
Stock-based compensation expense	2,000	'	2,000	'
Net loss	-872,000	'	'	-872,000
Ending balance at Dec. 31, 2009	-966,000	14,000	-10,000	-970,000
Ending balance, Shares at Dec. 31, 2009	'	14,488,000	'	'
Issuance of restricted common stock, Shares	'	219,000	'	'
Stock-based compensation expense	4,000	'	4,000	'
Net loss	-1,339,000	'	'	-1,339,000
Ending balance at Dec. 31, 2010	-2,301,000	14,000	-6,000	-2,309,000
Ending balance, Shares at Dec. 31, 2010	'	14,707,000	'	'
Issuance of common stock through conversion of notes payable	3,490,000	8,000	3,482,000	'
Issuance of common stock through conversion of notes payable, Shares	'	7,677,000	'	'
Issuance of warrants to consultants/Warrants issued with convertible notes and conversion of notes	1,111,000	'	1,111,000	'
Stock option exercises, Shares	'	'	'	'
Issuance of restricted common stock, Shares	'	61,000	'	'
Beneficial conversion feature of convertible notes payable	239,000	'	239,000	'
Stock-based compensation expense	9,000	'	9,000	'
Net loss	-4,383,000	'	'	-4,383,000
Ending balance at Dec. 31, 2011	-1,835,000	22,000	4,835,000	-6,692,000
Ending balance, Shares at Dec. 31, 2011	'	22,445,000	'	'
Issuance of common stock in connection with the merger	'	6,000	-6,000	'
Issuance of common stock in connection with the merger, Shares	'	6,000,000	'	'
Issuance of common stock through private placements in connection with reverse merger	13,723,000	14,000	13,709,000	'
Issuance of common stock through private placements in connection with reverse merger, Shares	'	13,723,000	'	'
Costs associated with the merger	-13,723,000	'	-13,723,000	'
Issuance of common stock through conversion of notes payable and accrued interest in connection with the merger	1,526,000	2,000	1,524,000	'
Issuance of common stock through conversion of notes payable and accrued interest in connection with the merger, Shares	'	1,525,000	'	'
Issuance of warrants to consultants/Warrants issued with convertible notes and conversion of notes	890,000	'	890,000	'
Issuance of common stock from warrant exercises, net	10,991,000	14,000	10,977,000	'
Issuance of common stock from warrant exercises, net, Shares	13,423,622	13,424,000	'	'
Warrant liability removed due to exercise of warrants	23,321,000	'	23,321,000	'
Stock option exercises	18,000	'	18,000	'
Stock option exercises, Shares	224,064	224,000	'	'
Issuance of restricted common stock	'	1,000	-1,000	'
Issuance of restricted common stock, Shares	'	1,380,000	'	'
Restricted stock forfeitures	'	'	'	'
Restricted stock forfeitures, Shares	'	-186,000	'	'
Stock-based compensation expense	1,435,000	'	1,435,000	'
Loss on inducement to exercise warrants	1,904,000	'	1,904,000	'
Net loss	-43,553,000	'	'	-43,553,000
Ending balance at Dec. 31, 2012	-5,303,000	59,000	44,883,000	-50,245,000
Ending balance, Shares at Dec. 31, 2012	'	58,535,000	'	'
Issuance of common stock from warrant exercises, net	3,724,000	6,000	3,718,000	'
Issuance of common stock from warrant exercises, net, Shares	6,131,198	6,131,000	'	'
Warrant liability removed due to exercise of warrants	23,869,000	'	23,869,000	'
Stock option exercises, Shares	'	'	'	'
Issuance of restricted common stock, Shares	'	55,000	'	'
Restricted stock forfeitures	'	'	'	'
Restricted stock forfeitures, Shares	'	-34,000	'	'
Stock-based compensation expense	848,000	'	848,000	'
Expense related to modification of warrants	65,000	'	65,000	'
Warrant liability reclassified to equity	1,886,000	'	1,886,000	'
Net loss	-16,120,000	'	'	-16,120,000
Ending balance at Mar. 31, 2013	8,969,000	65,000	75,269,000	-66,365,000
Ending balance, Shares at Mar. 31, 2013	'	64,687,000	'	'
Issuance of warrants to consultants/Warrants issued with convertible notes and conversion of notes	492,000	'	492,000	'
Issuance of common stock from warrant exercises, net	1,101,000	3,000	1,098,000	'
Issuance of common stock from warrant exercises, net, Shares	2,713,207	2,713,000	'	'
Warrant liability removed due to exercise of warrants	10,874,000	'	10,874,000	'
Stock option exercises	402,000	'	402,000	'
Stock option exercises, Shares	183,796	184,000	'	'
Issuance of restricted common stock, Shares	'	60,000	'	'
Restricted stock forfeitures	'	'	'	'
Restricted stock forfeitures, Shares	'	-215,000	'	'
Issuance of common stock from public offering	46,915,000	10,000	46,905,000	'
Issuance of common stock from public offering, Shares	'	10,684,000	'	'
Stock-based compensation expense	4,600,000	'	4,600,000	'
Expense related to modification of warrants	12,000	'	12,000	'
Warrant liability reclassified to equity	767,000	'	767,000	'
Net loss	-25,848,000	'	'	-25,848,000
Ending balance at Mar. 31, 2014	$48,284,000	$78,000	$140,419,000	($92,213,000)
Ending balance, Shares at Mar. 31, 2014	'	78,113,000	'	'

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	3 Months Ended		12 Months Ended			83 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2011	Mar. 31, 2014
Cash Flows From Operating Activities	'	'	'	'	'	'
Net loss	($16,120)	($37,081)	($25,848)	($43,553)	($4,383)	($92,213)
Adjustments to reconcile net loss to net cash used in operating activities:	'	'	'	'	'	'
Amortization of deferred financing costs	'	319	'	319	119	438
Amortization of warrants issued for services	261	'	323	556	'	1,140
Depreciation and amortization	80	17	387	195	68	818
Loss on disposal of fixed assets	'	'	84	158	'	242
Amortization of debt discount	'	896	'	896	1,188	2,084
Interest accrued on convertible notes payable	'	12	'	12	232	495
Fair value of warrant liabilities in excess of proceeds	'	19,019	'	19,019	'	19,019
Change in fair value of warrant liabilities	12,034	13,506	5,120	9,931	7	27,092
Loss on inducement to exercise warrants	'	'	'	1,904	'	1,904
Expense associated with warrant modification	65	'	12	'	'	77
Stock-based compensation	848	4	4,600	1,435	9	6,900
Warrants issued in connection with exchange agreement	'	'	'	'	528	528
Increase (decrease) in cash resulting from changes in:	'	'	'	'	'	'
Grants receivable	61	'	101	-162	60	'
Inventory	'	-45	25	-459	-224	-726
Prepaid expenses and other assets	-61	-65	-392	-101	-69	-647
Accounts payable	216	-217	-315	-233	373	326
Accrued expenses	-201	-37	387	543	132	1,167
Deferred revenue	62	116	-45	-153	46	17
Net cash used in operating activities	-2,755	-3,556	-15,561	-9,693	-1,914	-31,339
Cash Flows From Investing Activities	'	'	'	'	'	'
Deposits released from restriction (restricted cash deposits)	'	-38	9	-88	'	-79
Purchases of fixed assets	-137	-6	-277	-357	-46	-1,198
Purchases of intangible assets	-19	'	'	'	-65	-114
Net cash used in investing activities	-156	-44	-268	-445	-111	-1,391
Cash Flows From Financing Activities	'	'	'	'	'	'
Proceeds from issuance of convertible notes payable	'	'	'	'	2,543	4,630
Proceeds from issuance of common stock and exercise of warrants, net	3,724	13,723	48,016	24,714	'	76,454
Proceeds from exercise of stock options	'	'	402	18	'	420
Proceeds from issuance of related party notes payable	'	'	'	'	225	250
Principal payments on capital lease obligations	-2	'	-10	-7	'	-19
Repayment of related party notes payable	'	'	'	'	-250	-250
Repayment of convertible notes and interest payable	'	-110	'	-110	'	-110
Deferred financing costs	'	'	-40	'	-438	-478
Net cash provided by financing activities	3,722	13,613	48,368	24,615	2,080	80,897
Net Increase in Cash and Cash Equivalents	811	10,013	32,539	14,477	55	48,167
Cash and Cash Equivalents at Beginning of Period	14,817	340	15,628	340	285	'
Cash and Cash Equivalents at End of Period	15,628	10,353	48,167	14,817	340	48,167
Supplemental Disclosure of Cash Flow Information:	'	'	'	'	'	'
Interest	'	10	'	10	'	10
Income Taxes	'	$1	'	$1	$1	$3

Consolidated_Statements_of_Cas1

Consolidated Statements of Cash Flows (Parenthetical) (USD $)	3 Months Ended	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2013	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Statement Of Cash Flows [Abstract]	'	'	'	'	'
Issuance of restricted common stock to certain employees, advisors and consultants	'	'	'	'	219,369
Warrants and related beneficial conversion feature valued	'	'	'	$823	'
Warrant issued in connection with convertible notes payable	'	'	'	1,260	'
Issuance of common stock to note holders	'	'	1,525,387	7,676,828	'
Convertible notes principal balance	'	'	1,500	3,030	'
Accrued interest	'	'	25	460	'
Issued warrants with connection with reverse merger and private placement	'	'	32,743	'	'
Purchased equipment through capital lease	'	'	34	'	'
Transferred amount of inventory to fixed assets	272	'	391	'	'
Issued warrants to purchase shares of common stock for consulting services shares	'	75,000	650,000	'	'
Issued warrants to purchase shares of common stock for consulting services	'	404	890	'	'
Warrant liability reduced	23,869	10,874	23,321	'	'
Warrant reclassified as equity instruments	$1,886	$767	'	'	'

Change_in_Fiscal_Year_End

Change in Fiscal Year End	12 Months Ended
Change in Fiscal Year End	Mar. 31, 2014
Text Block [Abstract]	'
Change in Fiscal Year End	'
	1. Change in Fiscal Year End
	On March 31, 2013, the Board of Directors of the Company (the “Board”) approved a change in the Company’s fiscal year end from December 31st to March 31st. As a result of this change, the Company filed a Transition Report on Form 10-KT for the three-month transition period ended March 31, 2013. References to any of the Company’s pre-2013 fiscal years mean the fiscal year ending December 31 of that calendar year.

Description_of_Business_and_Su

Description of Business and Summary of Significant Accounting Policies

12 Months Ended

Mar. 31, 2014

Accounting Policies [Abstract]

Description of Business and Summary of Significant Accounting Policies

2. Description of Business and Summary of Significant Accounting Policies

A summary of significant accounting policies, consistently applied in the preparation of the accompanying consolidated financial statements follows:

Nature of operations and basis of presentation

References in these notes to the consolidated financial statements to “Organovo Holdings, Inc.,” “Organovo Holdings,” “we,” “us,” “our,” “the Company” and “our Company” refer to Organovo Holdings, Inc. and its consolidated subsidiary Organovo, Inc. The Company is developing and commercializing functional three-dimensional (3D) human tissues that can be employed in drug discovery and development, biological research, and as therapeutic implants for the treatment of damaged or degenerating tissues and organs.

As of March 31, 2014, the Company has devoted its efforts primarily to developing a platform technology for the generation of functional human tissues that can be employed in drug discovery and development, biological research, and as therapeutic implants for the treatment of damaged or degenerating tissues and organs, raising capital and building infrastructure. The Company has not realized significant revenues from its planned principal operations. Accordingly, the Company is considered to be in the development stage.

Reverse merger transaction

On February 8, 2012, Organovo, Inc., a privately held Delaware corporation, merged with and into Organovo Acquisition Corp., a wholly-owned subsidiary of Organovo Holdings, Inc., a publicly traded Delaware corporation (“the Company”), with Organovo, Inc. surviving the merger as a wholly-owned subsidiary of the Company (the “Merger”). As a result of the Merger, the Company acquired the business of Organovo, Inc., and has continued the existing business operations of Organovo, Inc.

Simultaneously with the Merger, on February 8, 2012 (the “Closing Date”), all of the issued and outstanding shares of Organovo, Inc.’s common stock converted, on a 1 for 1 basis, into shares of the Company’s common stock, par value $0.001 per share. Also, on the closing date, all of the issued and outstanding options to purchase shares of Organovo, Inc.’s common stock and other outstanding warrants to purchase Organovo, Inc.’s common stock, and all of the issued and outstanding bridge warrants to purchase shares of Organovo, Inc.’s common stock, converted on a 1 for 1 basis, into options, warrants and new bridge warrants to purchase shares of the Company’s common stock.

Immediately following the consummation of the Merger: (i) the former security holders of Organovo, Inc. common stock had an approximate 75% voting interest in the Company and the Company stockholders retained an approximate 25% voting interest, (ii) the former executive management team of Organovo, Inc. remained as the only continuing executive management team for the Company, and (iii) the Company’s ongoing operations consisted solely of the ongoing operations of Organovo, Inc. Based primarily on these factors, the Merger was accounted for as a reverse merger and a recapitalization in accordance with U.S. generally accepted accounting principles (“GAAP”). As a result, these financial statements reflect the historical results of Organovo, Inc. prior to the Merger, and the combined results of the Company following the Merger. The par value of Organovo, Inc. common stock immediately prior to the Merger was $0.0001 per share. The par value subsequent to the Merger is $0.001 per share, and therefore the historical results of Organovo, Inc. prior to the Merger have been retroactively adjusted to affect the change in par value.

In connection with three separate closings of a private placement transaction completed in connection with the Merger (the “Private Placement”), the Company received gross proceeds of approximately $5.0 million, $1.8 million and $6.9 million on closings on February 8, 2012, February 29, 2012 and March 16, 2012, respectively. In 2011, the Company received $1.5 million from the purchase of 6% convertible notes which were automatically converted into 1,500,000 shares of common stock, plus 25,387 shares for accrued interest of $25,387 on the principal, on February 8, 2012.

The cash transaction costs related to the Merger were approximately $2.1 million.

Before the Merger, the Company’s Board of Directors and stockholders adopted the 2012 Equity Incentive Plan (the “2012 Plan”). In addition, the Company assumed and adopted Organovo, Inc.’s 2008 Equity Incentive Plan.

NYSE MKT Listing

On July 9, 2013, the Company announced that its common stock had been approved to list on the NYSE MKT. Shares began trading on the New York Stock Exchange on July 11, 2013 under the symbol “ONVO”. Prior to that time, the Company’s shares were quoted on the OTC QX.

Liquidity

As of March 31, 2014, the Company had an accumulated deficit of approximately $92.2 million. The Company also had negative cash flows from operations of approximately $15.6 million during the year ended March 31, 2014.

In August of 2013, the Company raised net proceeds of approximately $43.4 million through the sale of 10,350,000 shares of its common stock in a public offering (see Note 7).

In addition, in November 2013, the Company entered into an equity distribution agreement with an investment banking firm. Under the terms of the distribution agreement, the Company may offer and sell up to 4,000,000 shares of its common stock, from time to time, through the investment bank in “at the market” offerings, as defined by the SEC, and pursuant to the Company’s effective shelf registration statement previously filed with the SEC. As of March 31, 2014, the Company has raised approximately $3.5 million through the sale of 334,412 shares of its common stock under the distribution agreement.

Through March 31, 2014, the Company has financed its operations primarily through the sale of convertible notes, the private placement of equity securities, the public offering of common stock, and through revenue derived from grants or collaborative research agreements. Based on its current operating plan and available cash resources, the Company has sufficient resources to fund its business for at least the next twelve months.

The Company will need additional capital to further fund product development and commercialization of its human tissues that can be employed in drug discovery and development, biological research, and as therapeutic implants for the treatment of damaged or degenerating tissues and organs. The Company intends to cover its future operating expenses through cash on hand, through additional financing from existing and prospective investors, from revenue derived from grants and collaborative research agreements, and revenue from the commercialization of products and services. However, we may not be successful in obtaining funding from new or existing collaborative research agreements. In addition, we cannot be sure that additional financing will be available when needed or that, if available, financing will be obtained on terms favorable to us or to our stockholders. Further, we cannot assure you that we will receive 100% of the potential funding under existing grants, and we may not be successful in securing additional grants in the future.

Having insufficient funds may require us to delay, scale back, or eliminate some or all of our development programs or relinquish rights to our technology on less favorable terms than we would otherwise choose. Failure to obtain adequate financing could eventually adversely affect our ability to operate as a going concern. If we raise additional funds from the issuance of equity securities, substantial dilution to our existing stockholders would likely result. If we raise additional funds by incurring debt financing, the terms of the debt may involve significant cash payment obligations as well as covenants and specific financial ratios that may restrict our ability to operate our business.

Use of estimates

The preparation of the financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect certain reported amounts and disclosures. Accordingly, actual results could differ from those estimates. Significant estimates used in preparing the consolidated financial statements include those assumed in computing the valuation of warrants and conversion features, revenue recognized under the proportional performance model, the valuation of stock-based compensation expense, and the valuation allowance on deferred tax assets.

Financial instruments

For certain of the Company’s financial instruments, including cash and cash equivalents, grants receivable, inventory, prepaid expenses and other assets, accounts payable, accrued expenses, deferred revenue, and capital lease obligations, the carrying amounts are generally considered to be representative of their respective fair values because of the short-term nature of those instruments.

Cash and cash equivalents

The Company considers all highly liquid investments with original maturities of 90 days or less to be cash equivalents.

Derivative financial instruments

The Company does not use derivative instruments to hedge exposures to cash flow, market or foreign currency.

The Company reviews the terms of convertible debt and equity instruments it issues to determine whether there are derivative instruments, including an embedded conversion option that is required to be bifurcated and accounted for separately as a derivative financial instrument. In circumstances where a host instrument contains more than one embedded derivative instrument, including a conversion option, that is required to be bifurcated, the bifurcated derivative instruments are accounted for as a single, compound derivative instrument. Also, in connection with the sale of convertible debt and equity instruments, the Company may issue freestanding warrants that may, depending on their terms, be accounted for as derivative instrument liabilities, rather than as equity.

Derivative instruments are initially recorded at fair value and are then revalued at each reporting date with changes in the fair value reported as non-operating income or expense. When the convertible debt or equity instruments contain embedded derivative instruments that are to be bifurcated and accounted for as liabilities, the total proceeds allocated to the convertible host instruments are first allocated to the fair value of all the bifurcated derivative instruments. The remaining proceeds, if any, are then allocated to the convertible instruments themselves, usually resulting in those instruments being recorded at a discount from their face value.

The discount from the face value of the convertible debt, together with the stated interest on the instrument, is amortized over the life of the instrument through periodic charges to interest expense, using the effective interest method.

Restricted cash

As of March 31, 2014, March 31, 2013, and December 31, 2012, the Company had approximately $78,800, $88,300, and $88,300, respectively, of restricted cash deposited with a financial institution. The entire $78,800 as of March 31, 2014 and $38,300 of the balance as of March 31, 2013 and December 31, 2012 was held in certificates of deposit to support a letter of credit agreement related to the facility lease entered into during 2012. In December 2013, the lease was amended to increase the rented area by 15,268 square feet, and as such, the Company was required to increase the amount held in certificates of deposit to support the increased letter of credit as required by the lease amendment. The additional $50,000 included in the balance as of March 31, 2013 and December 31, 2012 represents funds held by a financial institution as a guarantee for the Company’s commercial credit cards. These funds were released from restriction during the year ended March 31, 2014 as a result of the Company transferring its credit card program to a different financial institution.

Grant receivable

Grant receivable as of March 31, 2013 and December 31, 2012 represents the amount due from the National Institutes of Health (“NIH”) under a research grant that concluded in April 2013. The Company considers the grants receivable to be fully collectible; and accordingly, no allowance for doubtful amounts has been established. If amounts become uncollectible, they are charged to operations.

Inventory

Inventories are stated at the lower of the cost or market (first-in, first-out). Inventory consists of approximately $63,000, and $88,000 in raw materials as of March 31, 2014 and 2013, respectively, net of reserves. Inventory consists of approximately $196,000 in finished goods, $60,000 work-in-process and $104,000 in raw materials as of December 31, 2012.

The Company provides inventory allowances based on excess or obsolete inventories determined based on anticipated use in the final product. The reserve for obsolete inventory at March 31, 2014 was approximately $31,000. There was no reserve for obsolete inventory as of March 31, 2013 or December 31, 2012.

Fixed assets and depreciation

Property and equipment are carried at cost. Expenditures that extend the life of the asset are capitalized and depreciated. Depreciation and amortization are provided using the straight-line method over the estimated useful lives of the related assets or, in the case of leasehold improvements, over the lesser of the useful life of the related asset or the lease term. The estimated useful lives of the fixed assets range between two and five years.

Impairment of long-lived assets

In accordance with authoritative guidance the Company reviews its long-lived assets, including property and equipment and other assets, for impairment whenever events or changes in circumstances indicate that the carrying amounts of the assets may not be fully recoverable. To determine recoverability of its long-lived assets, the Company evaluates whether future undiscounted net cash flows will be less than the carrying amount of the assets and adjusts the carrying amount of its assets to fair value. Management has determined that no impairment of long-lived assets occurred in the period from inception through March 31, 2014.

Fair value measurement

Financial assets and liabilities are measured at fair value, which is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The following is a fair value hierarchy based on three levels of inputs, of which the first two are considered observable and the last unobservable, that may be used to measure fair value:

•

Level 1 — Quoted prices in active markets for identical assets or liabilities.

•

Level 2 — Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

•

Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

The Company has issued warrants, of which some are classified as derivative liabilities as a result of the terms in the warrants that provide for down-round protection in the event of a dilutive issuance. The Company uses Level 3 inputs for its valuation methodology for the warrant derivative liabilities. The estimated fair values were determined using a Monte Carlo option pricing model based on various assumptions (see Note 5). The Company’s derivative liabilities are adjusted to reflect estimated fair value at each period end, with any decrease or increase in the estimated fair value being recorded in other income or expense accordingly, as adjustments to the fair value of derivative liabilities. Various factors are considered in the pricing models we use to value the warrants, including the Company’s current stock price, the remaining life of the warrants, the volatility of the Company’s stock price, and the risk free interest rate. Future changes in these factors will have a significant impact on the computed fair value of the warrant liability. As such, we expect future changes in the fair value of the warrants to continue to vary significantly from quarter to quarter.

The estimated fair values of the liabilities measured on a recurring basis are as follows:

Fair Value Measurements at March 31, 2014, March 31, 2013, and December 31, 2012 (in thousands):

Balance at

Quoted

Significant

March 31,

Prices in

Other

2014

Active

Observable

Unobservable

Markets

Inputs

(Level 1)

(Level 2)

(Level 3)

Warrant liability

377

—

377

Balance at

Quoted

Significant

March 31,

Prices in

Other

2013

Active

Observable

Unobservable

Markets

Inputs

(Level 1)

(Level 2)

(Level 3)

Warrant liability

6,898

—

6,898

Balance at

Quoted

Significant

December 31,

Prices in

Other

2012

Active

Observable

Unobservable

Markets

Inputs

(Level 1)

(Level 2)

(Level 3)

Warrant liability

20,619

—

20,619

The following table presents the activity for liabilities measured at estimated fair value using unobservable inputs for the year ended December 2012, the three months ended March 31, 2013, and the year ended March 31, 2014:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

Warrant

Derivative

Liability

(in thousands)

Balance at December 31, 2011

1,267

Issuances

32,742

Adjustments to estimated fair value

9,931

Warrant liability removal due to settlements

(23,321

)

Balance at December 31, 2012

20,619

Issuances

—

Adjustments to estimated fair value

12,034

Warrant liability removal due to settlements

(23,869

)

Warrant liability reclassified to equity

(1,886

)

Balance at March 31, 2013

6,898

Issuances

—

Adjustments to estimated fair value

5,120

Warrant liability removal due to settlements

(10,874

)

Warrant liability reclassified to equity

(767

)

Balance at March 31, 2014

377

Research and development

Research and development expenses, including direct and allocated expenses, consist of independent research and development costs, as well as costs associated with sponsored research and development. Research and development costs are expensed as incurred.

Income taxes

Deferred income taxes are recognized for the tax consequences in future years for differences between the tax basis of assets and liabilities and their financial reporting amounts at each year end based on enacted tax laws and statutory tax rates applicable to the periods in which the differences are expected to affect taxable income. Valuation allowances are established when necessary to reduce deferred tax assets to the amount expected to be realized. Income tax expense is the combination of the tax payable for the year and the change during the year in deferred tax assets and liabilities.

Revenue recognition

The Company’s revenues are derived from collaborative research agreements, grants from the NIH, U.S. Treasury Department and private not-for-profit organizations, as well as the sale of bioprinter related products and services, and license agreements.

The Company recognizes revenue when the following criteria have been met: (i) persuasive evidence of an arrangement exists; (ii) services have been rendered or product has been delivered; (iii) price to the customer is fixed and determinable; and (iv) collection of the underlying receivable is reasonably assured.

Billings to customers or payments received from customers are included in deferred revenue on the balance sheet until all revenue recognition criteria are met. As of March 31, 2014, March 31, 2013, and December 31, 2012, the Company had approximately $17,000, $62,000, and $0, respectively, in deferred revenue related to its collaborative research programs.

Product Revenue

The Company recognizes product revenue at the time of shipment to the customer, provided all other revenue recognition criteria have been met. The Company recognizes product revenues upon shipment to distributors, provided that (i) the price is substantially fixed or determinable at the time of sale; (ii) the distributor’s obligation to pay the Company is not contingent upon resale of the products; (iii) title and risk of loss passes to the distributor at time of shipment; (iv) the distributor has economic substance apart from that provided by the Company; (v) the Company has no significant obligation to the distributor to bring about resale of the products; and (vi) future returns can be reasonably estimated. For any sales that do not meet all of the above criteria, revenue is deferred until all such criteria have been met.

Research and Development Revenue Under Collaborative Agreements

The Company’s collaboration revenue consists of license and collaboration agreements that contain multiple elements, including non-refundable upfront fees, payments for reimbursement of third-party research costs, payments for ongoing research, payments associated with achieving specific development milestones and royalties based on specified percentages of net product sales, if any. The Company considers a variety of factors in determining the appropriate method of revenue recognition under these arrangements, such as whether the elements are separable, whether there are determinable fair values and whether there is a unique earnings process associated with each element of a contract.

The Company recognizes revenue from research funding under collaboration agreements when earned on a “proportional performance” basis as research hours are incurred. The Company performs services as specified in each respective agreement on a best-efforts basis, and is reimbursed based on labor hours incurred on each contract. The Company initially defers revenue for any amounts billed or payments received in advance of the services being performed, and recognizes revenue pursuant to the related pattern of performance, based on total labor hours incurred relative to total labor hours estimated under the contract.

In December 2010, the Company entered into a 12 month research contract agreement with a third party, whereby the Company was engaged to perform research and development services on a fixed-fee basis for approximately $600,000. Based on the proportional performance criteria, the Company recognized approximately $150,000 and $450,000 in revenue related to the contract during the years ended December 31, 2012 and 2011, respectively. Total revenue recognized on the contract from inception through March 31, 2014 was approximately $600,000.

In October 2011, the Company entered into a research contract agreement with a third party, whereby the Company is performing research and development services on a fixed-fee basis for $1,365,000. The agreement included an initial payment to the Company of approximately $239,000 with remaining payments occurring over a twenty-one month period. On November 27, 2012, the agreement was amended to include additional research and development services, for an additional $135,000, bringing the total contract value to $1,500,000. The third party ultimately elected to have only $40,000 of these additional research and development services performed by the Company, resulting in a total contract value of $1,405,000. The amendment extended the original contract (which ran concurrently) from twenty-one months to twenty-eight months. The Company recorded approximately $184,000, $97,000, $120,000, $885,000 and $239,000 for the year ended March 31, 2014, the three months ended March 31, 2013 and 2012, and the years ended December 31, 2012 and 2011, respectively, in revenue related to the research contract in recognition of the proportional performance achieved. Total revenue recognized on the contract from inception through March 31, 2014 was $1,405,000.

Revenue Arrangements with Multiple Deliverables

The Company occasionally enters into revenue arrangements that contain multiple deliverables. Judgment is required to properly identify the accounting units of the multiple deliverable transactions and to determine the manner in which revenue should be allocated among the accounting units. Moreover, judgment is used in interpreting the commercial terms and determining when all criteria of revenue recognition have been met for each deliverable in order for revenue recognition to occur in the appropriate accounting period. For multiple deliverable agreements, consideration is allocated at the inception of the agreement to all deliverables based on their relative selling price. The relative selling price for each deliverable is determined using VSOE of selling price or third-party evidence of selling price if VSOE does not exist. If neither VSOE nor third-party evidence of selling price exists, the Company uses its best estimate of the selling price for the deliverable.

The Company recognizes revenue for delivered elements only when it determines there are no uncertainties regarding customer acceptance. While changes in the allocation of the arrangement consideration between the units of accounting will not affect the amount of total revenue recognized for a particular sales arrangement, any material changes in these allocations could impact the timing of revenue recognition, which could affect the Company’s results of operations.

The Company expects to periodically receive license fees for non-exclusive research licensing associated with funded research projects. License fees under these arrangements are recognized over the term of the contract or development period as it has been determined that such licenses do not have stand-alone value.

NIH and U.S. Treasury Grant Revenues

During 2010, the U.S. Treasury awarded the Company two one-time grants totaling approximately $397,000 for investments in qualifying therapeutic discovery projects under section 48D of the Internal Revenue Code. The grants covered reimbursement for qualifying expenses incurred by the Company in 2010 and 2009. The proceeds from these grants are classified in “Revenues — Grants” for the period from inception through March 31, 2014.

During 2012, 2010 and 2009, the NIH awarded the Company three research grants totaling approximately $558,000. Revenues from the NIH grants are based upon internal and subcontractor costs incurred that are specifically covered by the grants, and where applicable, an additional facilities and administrative rate that provides funding for overhead expenses. These revenues are recognized when expenses have been incurred by subcontractors and as the Company incurs internal expenses that are related to the grants. Revenue recognized under these grants for the year ended March 31, 2014, the three months ended March 31, 2013 and 2012, and the years ended December 31, 2012, and 2011 was approximately $12,000, $117,000, $0, $162,000, and $57,000, respectively. Total revenue recorded under these grants from inception through March 31, 2014 was approximately $558,000.

During August of 2013, the Company was awarded a research grant by a private, not-for-profit organization for up to $251,700, contingent on go/no-go decisions made by the grantor at the completion of each stage of research as outlined in the grant award. Revenues from the grant are based upon internal costs incurred that are specifically covered by the grant, plus an additional rate that provides funding for overhead expenses. Revenue is recognized when the Company incurs reimbursable expenses that are related to the grant. The Company recognized revenue from this grant of approximately $119,000 for the year ended March 31, 2014 and from inception to date.

Stock-based compensation

The Company accounts for stock-based compensation in accordance with the Financial Accounting Standards Board’s ASC Topic 718, Compensation — Stock Compensation, which establishes accounting for equity instruments exchanged for employee services. Under such provisions, stock-based compensation cost is measured at the grant date, based on the calculated fair value of the award, and is recognized as an expense, under the straight-line method, over the employee’s requisite service period (generally the vesting period of the equity grant).

The Company accounts for equity instruments, including restricted stock or stock options, issued to non-employees in accordance with authoritative guidance for equity based payments to non-employees. Stock options issued to non-employees are accounted for at their estimated fair value determined using the Black-Scholes option-pricing model. The fair value of options granted to non-employees is re-measured as they vest, and the resulting increase in value, if any, is recognized as expense during the period the related services are rendered. Restricted stock issued to non-employees is accounted for at their estimated fair value as they vest.

Comprehensive income (loss)

Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources. The Company is required to record all components of comprehensive income (loss) in the financial statements in the period in which they are recognized. Net income (loss) and other comprehensive income (loss), including unrealized gains and losses on investments, are reported, net of their related tax effect, to arrive at comprehensive income (loss). For the year ended March 31, 2014, the three months ended March 31, 2013 and 2012, and the years ended December 31, 2012 and 2011, and for the period April 19, 2007 (inception) through March 31, 2014, the comprehensive loss was equal to the net loss.

Net loss per share

Basic and diluted net loss per share has been computed using the weighted-average number of shares of common stock outstanding during the period. The weighted-average number of shares used to compute diluted loss per share excludes any assumed exercise of stock options, and the assumed issuance of common stock under restricted stock units, shares subject to repurchase and warrants as the effect would be anti-dilutive. No dilutive effect was calculated for the year ended March 31, 2014, the three months ended March 31, 2013 or 2012, or the years ended December 31, 2012 or 2011 as the Company reported a net loss for each respective period and the effect would have been anti-dilutive. Total common stock equivalents that were excluded from computing diluted net loss per share were approximately 7.7 million, 8.9 million, 25.8 million, 15.2 million, and 6.4 million for the year ended March 31, 2014, the three months ended March 31, 2013 and 2012 and the years ended December 31, 2012 and 2011, respectively.

Reclassifications

Certain reclassifications were made to the 2011 financial statements in order to conform to the presentation of the financial statements for 2012. The reclassifications did not have any effect on previously reported net loss or stockholders’ equity (deficit).

Fixed_Assets

Fixed Assets	12 Months Ended
Fixed Assets	Mar. 31, 2014
Property Plant And Equipment [Abstract]	'
Fixed Assets	'
	3. Fixed Assets
	Fixed assets consisted of the following (in thousands):


		March 31,			March 31,			December 31,
		2014			2013			2012
	Laboratory equipment	$	1,207		$	1,168		$	759
	Computer software and equipment		191			114			114
	Furniture and fixtures		33			33			33

			1,431			1,315			906

	Less accumulated depreciation and amortization		(574	)		(270	)		(192	)

		$	857		$	1,045		$	714

	Depreciation and amortization expense for the year end March 31, 2014, the three months ended March 31, 2013 and March 31, 2012, and the years ended December 31, 2012 and December 31, 2011 was approximately $380,000, $78,000, $15,000, $188,000 and $63,000, respectively. Depreciation and amortization expense was approximately $794,000 for the period from April 19, 2007 (inception) through March 31, 2014.

Accrued_Expenses

Accrued Expenses	12 Months Ended
Accrued Expenses	Mar. 31, 2014
Payables And Accruals [Abstract]	'
Accrued Expenses	'
	4. Accrued Expenses
	Accrued expenses consisted of the following (in thousands):


		March 31,		March 31,		December 31,
		2014		2013		2012
	Accrued compensation	$	505	$	386	$	720
	Deferred rent		345		270		188
	Accrued legal and professional fees		283		53		—
	Other accrued expenses		34		71		73

		$	1,167	$	780	$	981

Derivative_Liability

Derivative Liability	12 Months Ended
Derivative Liability	Mar. 31, 2014
Derivative Instruments And Hedging Activities Disclosure [Abstract]	'
Derivative Liability	'
	5. Derivative Liability
	During 2012, in relation to the reverse Merger and the three offerings under the Private Placement, the Company issued 21,347,182 five-year warrants to purchase the Company’s common stock. In October and November of 2011, the Company issued 1,500,000 five-year warrants in connection with Convertible Notes. The exercise price of the warrants is protected against down-round financing throughout the term of the warrant, as described below. Pursuant to ASC 815-15 and ASC 815-40, the fair value of the warrants of approximately $32.7 million and $1.3 million in 2012 and 2011, respectively, was recorded as a derivative liability on the issuance dates.
	The Company revalued the warrants as of the end of each reporting period, and the estimated fair value of the outstanding warrant liabilities was $0.4 million, $6.9 million, $20.6 million and $1.3 million as of March 31, 2014, March 31, 2013, and December 31, 2012 and December 31, 2011, respectively. The changes in fair value of the derivative liabilities for the year ended March 31, 2014, the three months ended March 31, 2013 and 2012, and the years ended December 31, 2012 and 2011 were increases of $5.1 million, $12.0 million, $13.5 million, $9.9 million and less than $0.1 million, respectively, and are included in other income (expense) in the statements of operations.
	During the year ended March 31, 2014, the three months ended March 31, 2013 and the year ended December 31, 2012, 1,920,874, 6,990,556 and 13,010,237 warrants that were classified as derivative liabilities were exercised. The warrants were revalued as of the settlement date, and the change in fair value was recognized to earnings. In addition, in the year ended March 31, 2014 and the three months ended March 31, 2013 the Company entered into amendment agreements with certain of the warrant holders, which removed the down-round pricing protection provision, resulting in 269,657 and 601,735, respectively, of these warrants being reclassified from liability instruments to equity instruments. The Company also recognized a reduction in the warrant liability based on the fair value as of the settlement date for the warrants exercised and as of the modification date for the warrants that were amended, with a corresponding increase in additional paid-in capital.
	The derivative liabilities were valued at the closing dates of the Private Placement and the end of each reporting period using a Monte Carlo valuation model with the following assumptions:


		March 31,			March 31,			December 31,
		2014			2013			2012
	Closing price per share of common stock	$	7.64		$	3.68		$	2.6
	Exercise price per share	$	1		$	1		$	1
	Expected volatility		76.5	%		88.8	%		92.9	%
	Risk-free interest rate		0.9	%		0.57	%		0.54	%
	Dividend yield		—			—			—
	Remaining expected term of underlying securities (years)		2.96			3.88			4.16
	In addition, as of the valuation dates, management assessed the probabilities of future financings assumptions in the Monte Carlo valuation models. Management also applied a discount for lack of marketability to the valuation of the derivative liabilities based on such trading restrictions due to certain of the shares not being registered.

	In accordance with the terms of the warrant agreements, if, prior to the expiration date of the warrants, the Company issues additional shares of common stock, as defined below, without consideration or for a consideration per share less than the exercise price of the warrants in effect immediately prior to such issue, then the exercise price shall be reduced, concurrently with such issue, to a price (calculated to the nearest cent) determined by multiplying such exercise price by a fraction, (A) the numerator of which shall be (1) the number of shares of common stock outstanding immediately prior to such issue plus (2) the number of shares of common stock which the aggregate consideration received or to be received by the Company for the total number of additional shares of common stock so issued would purchase at such exercise price; and (B) the denominator of which shall be the number of shares of common stock outstanding immediately prior to such issue plus the number of such additional shares of common stock so issued; provided that (i) all shares of common stock issuable upon conversion or exchange of convertible securities outstanding immediately prior to such issue shall be deemed to be outstanding, and (ii) the number of shares of common stock deemed issuable upon conversion or exchange of such outstanding convertible securities shall be determined without giving effect to any adjustments to the conversion or exchange price or conversion or exchange rate of such convertible securities resulting from the issuance of additional shares of common stock that is the subject of this calculation. For purposes of the warrants, “additional shares of common stock” shall mean all shares of common stock issued by the Company after the effective date (including without limitation any shares of common stock issuable upon conversion or exchange of any convertible securities or upon exercise of any option or warrant, on an as-converted basis), other than: (i) shares of common stock (and/or warrants for any class of equity securities of the Company) issued or issuable upon conversion or exchange of any convertible securities or exercise of any options or warrants outstanding on the effective date; (ii) shares of common stock issued or issuable by reason of a dividend, stock split, split-up or other distribution on shares of common stock; (iii) shares of common stock (or options with respect thereto) issued or issuable to employees or directors of, or consultants to, the Company or any of its subsidiaries pursuant to a plan, agreement or arrangement approved by the Board of Directors of the Company; (iv) any securities issued or issuable by the Company pursuant to (A) the Private Placement; or (B) the Merger; (v) securities issued pursuant to acquisitions or strategic transactions approved by a majority of disinterested directors of the Company, provided that any such issuance shall only be to a person which is, itself or through its subsidiaries, an operating company in a business synergistic with the business of the Company and in which the Company receives benefits in addition to the investment of funds, but shall not include a transaction in which the Company is issuing securities primarily for the purpose of raising capital or to an entity whose primary business is investing in securities and (vi) securities issued to financial institutions, institutional investors or lessors in connection with credit arrangements, equipment financings or similar transactions approved by a majority of disinterested directors of the Company, but shall not include a transaction in which the Company is issuing securities primarily for the purpose of raising capital or to an entity whose primary business is investing in securities.
	Upon each adjustment of the exercise price pursuant to the provisions stated above, the number of warrant shares issuable upon exercise of the warrants shall be adjusted by multiplying a number equal to the exercise price in effect immediately prior to such adjustment by the number of warrant shares issuable upon exercise of the warrant immediately prior to such adjustment and dividing the product so obtained by the adjusted exercise price.

Convertible_Notes_Payable

Convertible Notes Payable	12 Months Ended
Convertible Notes Payable	Mar. 31, 2014
Text Block [Abstract]	'
Convertible Notes Payable	'
	6. Convertible Notes Payable
	Convertible notes
	From February 9, 2008 through December 31, 2011, the Company raised an aggregate of $2,390,000 in funds through loans consisting of convertible notes (“Convertible Notes”) to certain stockholders, management, vendors, and investors. The notes bore interest at rates ranging from 8% to 10% per annum and had maturity dates ranging from 2011 to 2018. The Convertible Notes were unsecured and subordinated to certain senior indebtedness of the Company, and for all Convertible Notes the principal plus accrued interest was convertible into the Company’s common stock. During October 2011, in connection with the Exchange Agreement and Release, the Convertible Notes and accrued interest converted into the Company’s common stock.

	Local Bridge
	During July and August 2011, $740,000 of Convertible Notes bearing interest at 20% per annum, and warrants to purchase shares of common stock were issued to investors. The Convertible Notes were due at the earlier of 1) one year from the issuance date or 2) one week after the consummation of a Merger transaction. The number of warrants to be issued was equal to the note principal divided by the exercise price. The exercise price was the per share or per unit fair market value received in the Merger. The notes were convertible at a price per share equal to seventy-five percent (75%) of the per share fair market value of the total consideration received for a share of a public company’s common stock to be determined to be identified upon consummation of a merger.
	The Company determined that the beneficial conversion feature and the warrants did not represent embedded derivative instruments. Additionally, at issuance of the Convertible Notes, the Company did not record the discount for the beneficial conversion feature due to the contingencies surrounding conversion. The beneficial conversion feature was recorded when the contingencies were resolved. In accordance with ASC 470-20, Debt with Conversion and Other Options, the Company recorded a discount of approximately $583,700 for the warrants in 2011. The discount was amortized to interest expense over the term of the Convertible Notes using the effective interest method.
	The Company calculated the fair value of the warrants using the Black-Scholes Model using a volatility of 109.84%, an interest rate of 1.12% and a dividend yield of zero. Certain of these Convertible Notes and accrued interest were converted into the Company’s common stock in October 2011, in connection with the Exchange Agreement and Release, as discussed below. Upon conversion the Company recognized the unamortized debt discount related to these notes to interest expense. The Company recognized approximately $583,700 of interest expense for the amortization of the note discount during the year ended December 31, 2011.
	Exchange Agreement and Release
	In October 2011, the Company’s Board of Directors and stockholders approved an Exchange Agreement, whereby the note holders could exchange their Convertible Notes and accrued interest for shares of the Company’s common stock and warrants to purchase the Company’s common stock. A total of $3,030,000 of principal and approximately $459,800 of accrued interest converted, at prices ranging from $0.27 to $0.75, into 7,676,828 shares of the Company’s common stock, plus five-year warrants to purchase 1,309,750 common shares at an exercise price of $1.00 per share. For the holders that elected to participate, the Exchange Agreement and Release resulted in the cancellation of the Convertible Notes and release from the note holders for any claims related to the Convertible Notes.
	The Company determined that the warrants issued in connection with the Exchange Agreement and Release did not represent derivative instruments. The warrants, valued at approximately $527,600, were classified as equity instruments and recorded as interest expense on the date of issuance in 2011. The Company calculated the fair value of the warrants using the Black-Scholes Model, using a volatility of 110.13%, an interest rate of 1.11% and a dividend yield of zero.
	At December 31, 2011, an unsecured $100,000 Convertible Note, with interest at 10% and a maturity date of April 2014, remained outstanding. In February 2012, at the close of the Merger, the convertible note and accrued interest in the aggregate of approximately $110,000 were repaid.
	2011 Private placement
	On September 18, 2011, Organovo, Inc.’s Board of Directors authorized a private placement offering of up to 30 Units of its securities at a price of $50,000 per Unit for an aggregate purchase price of $1,500,000. Each Unit consisted of a convertible note in the principal amount of $50,000 accruing simple interest at the rate of 6% per annum (the “Convertible Notes”), plus five-year warrants to purchase 50,000 shares of the next Qualified Round of Equity Securities, at an exercise price of $1.00 per share. The principal plus accrued interest was convertible into the Company’s common stock upon consummation of a Merger transaction.

	During October and November 2011, $1,500,000 of Convertible Notes bearing interest at 6% per annum with a maturity date of March 30, 2012, and five-year warrants to purchase 1,500,000 shares of the Company’s common stock were issued to investors under the Private Placement. The warrants are exercisable at $1.00 per share, expire in five years, and contain down-round price protection. The Convertible Notes were outstanding at December 31, 2011, and were converted into 1,525,387 Units during February 2012, in connection with the Merger.
	The Company determined that the warrants represent a derivative instrument due to the down-round price protection, and accordingly, the Company recorded a derivative liability related to the warrants, with a corresponding debt discount of approximately $1,260,300. See Note 5. Additionally, upon issuance of the notes during 2011, the Company recorded the discount for the beneficial conversion feature of $239,700. The debt discount associated with the warrants and beneficial conversion feature were amortized to interest expense over the life of the Convertible Notes, and fully amortized upon conversion of the Convertible Notes in 2012. The Company recorded approximately $896,200 and $603,800 of interest expense for the amortization of the debt discount during the years ended December 31, 2012 and 2011, respectively, and approximately $1,500,000 for the period from inception through March 31, 2014.
	As consideration for locating investors to participate in the Private Placement, the placement agent earned a cash payment of $195,000 in 2011. Additionally, upon closing of the Merger transaction in 2012, the placement agent earned five-year warrants to purchase 610,155 shares of the Company’s common stock at $1.00 per share. These warrants contain down round protection and were classified as derivative liabilities upon issuance. See Note 5.
	2012 Private placement
	During 2012, concurrently with the closing of the Merger and in contemplation of the Merger, the Company completed the initial closing of the Private Placement of up to 8,000,000 Units of its securities, at a price of $1.00 per Unit, with the ability to increase the offering to an aggregate of up to 16,000,000 Units. Each Unit consisted of one share of common stock and a warrant to purchase one share of common stock. The Company completed three closings under the Private Placement during 2012, and raised total gross proceeds of $13,722,600 and total net proceeds of $11,593,066. The Company issued 13,722,600 shares of its common stock and warrants to purchase 15,247,987 shares of its common stock (including warrants to purchase 1,525,387 shares to former holders of the Convertible Notes) exercisable at $1.00 to investors in the Offering. The placement agent and its selected dealers were paid total cash commissions of $1,372,260 and the placement agent was paid an expense allowance of $411,678 and was issued placement agent warrants to purchase 6,099,195 shares of the Company’s common stock at an exercise price of $1.00 per share.
	The warrants issued to the investors and the placement agent, as described above, contain down round protection, and accordingly, were classified as derivative liabilities upon issuance. On the closing date, the derivative liabilities were recorded at an estimated fair value of approximately $32,742,000. Given that the fair value of the derivative liabilities exceeded the total proceeds of the private placement of $13,722,600, no net amounts were allocated to the common stock. The amount by which the recorded liabilities exceeded the proceeds of approximately $19,019,400 was charged to other expense at the closing dates. The Company has revalued the derivative liability as of each reporting period, and will continue to do so on each subsequent balance sheet date until the securities to which the derivative liabilities relate are exercised or expire, with any changes in the fair value recognized through earnings in the statement of operations. See Note 5.
	Interest expense, including amortization of the note discounts and other interest expense was approximately $13,000, $65,000, $1,088,000, $1,088,000, and $2,067,000 for the year ended March 31, 2014, the three months ended March 31, 2013 and 2012, and the years ended December 31, 2012, and 2011, respectively. Interest expense, including amortization of the note discounts and other interest expense, for the period from April 19, 2007 (inception) through March 31, 2014 was approximately $3,484,000.

	Registration rights agreement
	The Company entered into a registration rights agreement (“Registration Rights Agreement”) with the investors in the Offering. Under the terms of the Registration Rights Agreement, the Company agreed to file a registration statement covering the resale of the common stock underlying the Units and the common stock that is issuable on exercise of the Investor Warrants (but not the common stock that is issuable upon exercise of the warrants issued as compensation to the placement agent in connection with the Offering) within 90 days from the final closing date of the Offering (the “Filing Deadline”). The Company filed the registration statement on June 13, 2012. The registration statement became effective during July 2012.
	The Company agreed to use reasonable efforts to maintain the effectiveness of the registration statement through the one year anniversary from the date the registration statement was declared effective by the Securities and Exchange Commission (the “SEC”), or until Rule 144 of the 1933 Act is available to investors in the Offering with respect to all of their shares, whichever is earlier. If the Company had not met the Effectiveness Deadline, the Company would have been liable for monetary penalties equal to one-half of one percent (0.5%) of each investor’s investment in the offering at the end of every 30 day period following such Effectiveness Deadline failure until such failure was cured. No payments shall be owed with respect to any period during which all of the investor’s registrable securities may be sold by such investor under Rule 144 or pursuant to another exemption from registration.

Stockholders_Equity

Stockholders' Equity	12 Months Ended
Stockholders' Equity	Mar. 31, 2014
Equity [Abstract]	'
Stockholders' Equity	'
	7. Stockholders’ Equity
	Common stock
	In October 2011, the Company issued 7,676,828 shares of common stock to note holders for the conversion of Convertible Notes with a principal balance totaling $3,030,000 and accrued interest totaling approximately $459,800.
	During February and March 2012, the Company issued 21,247,987 shares of common stock related to the Merger. See Note 2. During the year ended December 31, 2012, the Company issued 13,423,622 shares of common stock upon exercise of 13,532,487 warrants.
	During the year ended December 31, 2012, a total of 224,064 stock options were exercised for 224,064 shares of common stock.
	During the three months ended March 31, 2013, the Company issued 6,131,198 shares of common stock upon exercise of 7,090,556 warrants.
	A shelf registration statement on Form S-3 (File No. 333-189995), or shelf, was filed with the SEC on July 17, 2013 authorizing the offer and sale in one or more offerings of up to $100,000,000 in aggregate of common stock, preferred stock, debt securities, warrants to purchase common stock, preferred stock or debt securities, or any combination of the foregoing, either individually or as units comprised of one or more of the other securities. This shelf was declared effective by the SEC on July 26, 2013.
	On August 2, 2013, the Company, entered into an Underwriting Agreement (the “Underwriting Agreement”) with Lazard Capital Markets LLC, acting as representative of the underwriters named in the Underwriting Agreement (the “Underwriters”) and joint book-runner with Oppenheimer & Co. Inc., relating to the issuance and sale of 10,350,000 shares of the Company’s common stock, which includes the issuance and sale of 1,350,000 shares pursuant to an overallotment option exercised by the Underwriters on August 5, 2013. JMP Securities LLC and Maxim Group LLC each acted as co-managers for the offering. The price to the public in the Offering was $4.50 per share, and the Underwriters purchased the shares from the Company pursuant to the Underwriting Agreement at a price of $4.23 per share. The net proceeds to the Company from the Offering were approximately $43.4 million, after deducting underwriting discounts and commissions and other offering expenses of $3.2 million payable by the Company, including the Underwriters’ exercise of the overallotment option. The transactions contemplated by the Underwriting Agreement closed on August 7, 2013.

	The Underwriting Agreement contained customary representations, warranties and agreements by the Company, customary conditions to closing, indemnification obligations of the Company and the Underwriters, including for liabilities under the Securities Act, other obligations of the parties and termination provisions.
	The representations, warranties and covenants contained in the Underwriting Agreement were made only for purposes of the Underwriting Agreement as of specific dates indicated therein, were solely for the benefit of the parties to the Underwriting Agreement, and may be subject to limitations agreed upon by the parties, including being qualified by confidential disclosures exchanged between the parties in connection with the execution of the Underwriting Agreement.
	In November 2013, the Company entered into an equity distribution agreement with an investment banking firm. Under the terms of the distribution agreement, the Company may offer and sell up to 4,000,000 shares of its common stock, from time to time, through the investment bank in “at the market” offerings, as defined by the SEC, and pursuant to the Company’s effective shelf registration statement previously filed with the SEC. During the year ended March 31, 2014, the Company issued 334,412 shares of common stock in at-the-market offerings under the distribution agreement with net proceeds of $3.5 million.
	In addition, during the year ended March 31, 2014, the Company issued 2,713,207 shares of common stock upon exercise of 3,201,633 warrants.
	During the year ended March 31, 2014, the Company issued 183,796 shares of common stock upon exercise of 183,796 options.
	Restricted stock awards
	In February 2008, four founders, including the Chief Executive Officer (“CEO”) and three directors of the Company received 11,779,960 shares of restricted common stock, 25% vesting after the first year and the remaining 75% vesting in equal quarterly portions over the following three years. These shares are fully vested as of March 31, 2014.
	In May of 2008, the Board of Directors of the Company approved the 2008 Equity Incentive Plan (the “2008 Plan”). The 2008 Plan authorized the issuance of up to 1,521,584 common shares for awards of incentive stock options, non-statutory stock options, restricted stock awards, restricted stock award units, and stock appreciation rights. The 2008 Plan terminates on July 1, 2018. No shares were issued under the 2008 Plan during the year ended December 31, 2012, the three months ended March 31, 2013, or the year ended March 31, 2014, and the Company does not intend to issue any additional shares from the 2008 Plan in the future.
	From 2008 through December 31, 2011, the Company issued a total of 1,258,934 shares of restricted common stock to various employees, advisors, and consultants of the Company. Of those shares, 1,086,662 were issued under the 2008 Plan and the remaining 172,272 shares were issued outside the plan.
	In January of 2012, the Board of Directors of the Company approved the 2012 Equity Incentive Plan (the “2012 Plan). The 2012 Plan authorized the issuance of up to 6,553,986 shares of common stock for awards of incentive stock options, non-statutory stock options, stock appreciation rights, restricted stock, restricted stock units, performance units, performance shares, and other stock or cash awards. In August 2013, the Board of Directors of the Company approved an amendment to the 2012 Plan to increase the number of shares of common stock that may be issued under the 2012 Plan by 5,000,000 shares, for an aggregate of 11,553,986 shares issuable under the 2012 Plan. The 2012 Plan terminates ten years after its adoption.
	During the year ended December 31, 2012, the Company issued an aggregate 950,000 of restricted stock awards to certain members of senior management and 130,000 restricted stock awards to non-executive employees. The vesting schedule is 25% on each anniversary of the vesting start date over four years. Additionally, the Company issued 100,000 restricted stock awards to a consultant. The vesting schedule is 100% after 6 months.

	During the year ended December 31, 2012, the Company issued an aggregate 200,000 restricted stock awards to a member of senior management, the vesting of which is performance based. As of March 31, 2014, the Company believed the financial targets would be met, and accordingly is recognizing the related stock based compensation expense over the requisite service period.
	During the year ended December 31, 2012, there were 95,842 restricted stock awards forfeited by staff members upon termination of their employment with the Company. Additionally, 89,674 restricted stock awards were surrendered related to shares of common stock returned to the Company, at the option of the holders, to cover the tax liability related to the vesting of 211,250 restricted stock awards. Upon the return of the common stock, 89,674 stock option grants with immediate vesting were granted to the individuals at the vesting date market value strike price.
	During the three months ended March 31, 2013, the Company issued an aggregate of 55,000 restricted stock awards with immediate vesting to a consultant.
	During the three months ended March 31, 2013, there were 10,000 restricted stock awards forfeited by one staff member upon termination of their employment with the Company. Additionally, 24,690 restricted stock awards were surrendered related to shares of common stock returned to the Company, at the option of the holder, to cover the tax liability related to the vesting of 50,000 restricted stock awards. Upon the return of the common stock, 24,690 stock option grants with immediate vesting were granted to the individual at the vesting date market value strike price.
	During the year ended March 31, 2014, 218,655 restricted stock awards were surrendered related to shares of common stock returned to the Company, at the option of the holder, to cover the tax liability related to the vesting of 405,000 restricted stock awards. Upon the return of the common stock, 218,655 stock option grants with immediate vesting were granted to the individual at the vesting date market value strike price.
	During the year ended March 31, 2014, the Company issued an aggregate of 60,000 restricted stock units with immediate vesting to a consultant.

	A summary of the Company’s restricted stock award activity is as follows:


			Number of
			Shares
	Unvested at December 31, 2007			—
	Granted			12,627,697
	Vested			(65,211	)
	Canceled / forfeited			—

	Unvested at December 31, 2008			12,562,486
	Granted			130,422
	Vested			(5,373,004	)
	Canceled / forfeited			—

	Unvested at December 31, 2009			7,319,904
	Granted			219,369
	Vested			(3,256,191	)
	Canceled / forfeited			—

	Unvested at December 31, 2010			4,283,082
	Granted			61,406
	Vested			(3,233,193	)
	Canceled / forfeited			—

	Unvested at December 31, 2011			1,111,295
	Granted			1,380,000
	Vested			(1,233,409	)
	Canceled / forfeited			(95,842	)

	Unvested at December 31, 2012			1,162,044
	Granted			55,000
	Vested			(221,302	)
	Canceled / forfeited			(10,000	)

Unvested at March 31, 2013			985,742
Granted			60,000
Vested			(472,247	)
Canceled / forfeited			—

Unvested at March 31, 2014			573,495

The fair value of each restricted common stock award is recognized as stock-based expense over the vesting term of the award. The Company recorded restricted stock-based compensation expense in operating expenses for employees and non-employees of approximately $817,000, $478,000, $0, $835,000, and $3,000 during the year ended March 31, 2014, the three months ended March 31, 2013 and March 31, 2012, and the years ended December 31, 2012, and 2011, respectively. The Company recorded restricted stock-based compensation expense of approximately $2,141,000 for the period from April 19, 2007 (inception) through March 31, 2014. Expense for each of the periods included approximately $16,000, $4,000, $0, $23,000, and $0 for research and development during the year ended March 31, 2014, the three months ended March 31, 2013 and March 31, 2012, and the years ended December 31, 2012, and 2011, respectively. General and administrative expense for the year ended March 31, 2014, the three months ended March 31, 2013 and March 31, 2012, and the years ended December 31, 2012, and 2011 were approximately $801,000, $474,000, $0, $812,000, and $3,000, respectively.
As of March 31, 2014, total unrecognized restricted stock-based compensation expense was approximately $747,000, which will be recognized over a weighted average period of 1.46 years.

Stock options
Under the 2008 Equity Incentive Plan, on October 12, 2011, the Company granted an officer incentive stock options to purchase 896,256 shares of common stock at an exercise price of $0.08 per share, a quarter of which vested on the one year anniversary of employment, in May 2012, and the remaining options are vesting ratably over the remaining 36 month term. Other than this grant, the Company does not intend to issue any additional shares under the 2008 Plan.
During the year ended March 31, 2014, the three months ended March 31, 2013, and the year ended December 31, 2012, under the 2012 Equity Incentive Plan, 2,519,572, 927,981 and 2,023,394 incentive stock options were issued, respectively, at various exercise prices, a quarter of which will vest on either the one year anniversary of employment or one year anniversary of the vesting commencement date. The remaining options will vest ratably over the remaining 36 month terms, with the exception of 218,655, 24,690 and 83,986 of the incentive stock option grants during the year ended March 31, 2014, the three month period ended March 31, 2013, and the year ended December 31, 2012, respectively, that have immediate vesting at the grant date, 99,500 and 126,000 of the incentive stock option grants in the years ended March 31, 2014 and December 31, 2012, respectively, that vest quarterly over three years, and 122,500 and 70,750 of the incentive stock option grants in the years ended March 31, 2014 and December 31, 2012, respectively, that vest after one full year.
The following table summarizes stock option activity for 2010 through March 31, 2014:


		Options				Weighted-			Aggregate
		Outstanding				Average			Intrinsic
						Exercise Price			Value
Outstanding at December 31, 2010			—				—			—
Options granted			896,256			$	0.08
Options canceled			—				—
Options exercised			—				—

Outstanding at December 31, 2011			896,256			$	0.08			—
Options granted			2,023,394			$	1.95
Options canceled			(5,000	)		$	2.25
Options exercised			(224,064	)		$	0.08		$	564,641

Outstanding at December 31, 2012			2,690,586			$	1.48		$	3,041,476
Options granted			927,981			$	3.93
Options canceled			—				—
Options exercised			—				—			—

Outstanding at March 31, 2013			3,618,567			$	2.11		$	5,909,154
Options granted			2,519,572			$	8.63
Options canceled			(18,455	)			3.31
Options exercised			(183,796	)			2.19		$	1,002,419

Outstanding at March 31, 2014			5,935,888			$	4.87		$	20,482,823

Vested and Exercisable at March 31, 2014			1,546,377			$	2.73		$	7,733,041

The weighted-average remaining contractual term of options exercisable and outstanding at March 31, 2014 was approximately 8.5 years and 8.92 years, respectively.

The Company uses the Black-Scholes valuation model to calculate the fair value of stock options. Stock based compensation expense is recognized over the vesting period using the straight-line method. The fair value of stock options was estimated at the grant date using the following weighted average assumptions:


		Year Ended				Three Months			Year Ended
		March 31, 2014				Ended			December 31, 2012
						March 31, 2013
Dividend yield			—				—			—
Volatility			78.22	%			96.83	%		96.22	%
Risk-free interest rate			1.32	%			1.19	%		0.89	%
Expected life of options			6.00 years				6.07 years			6.05 years
Weighted average grant date fair value		$	5.92			$	3.04		$	1.5
The assumed dividend yield was based on the Company’s expectation of not paying dividends in the foreseeable future. Due to the Company’s limited historical data, the estimated volatility incorporates the historical and implied volatility of comparable companies whose share prices are publicly available. The risk-free interest rate assumption was based on the U.S. Treasury rates. The weighted average expected life of options was estimated using the average of the contractual term and the weighted average vesting term of the options. Certain options granted to consultants are subject to variable accounting treatment and are required to be revalued until vested.
The total stock option based compensation recorded as operating expense was approximately $3,783,000, $370,000, $4,000, $600,000, and $6,000 for the year ended March 31, 2014, the three months ended March 31, 2013 and March 31, 2012, and the years ended December 31, 2012, and 2011, respectively. The Company recorded stock-based compensation expense of approximately $4,761,000 for the period from April 19, 2007 (inception) through March 31, 2014. Expense for each of the periods included approximately $462,000, $58,000 and $81,000 for research and development during the year ended March 31, 2014, the three months ended March 31, 2013, and the year ended December 31, 2012, respectively. General and administrative expense for the year ended March 31, 2014, the three months ended March 31, 2013 and March 31, 2012, and years ended December 31, 2012, and 2011 were approximately $3,321,000, $312,000, $4,000, $519,000, and $6,000 respectively.
The total unrecognized compensation cost related to unvested stock option grants as of March 31, 2014 was approximately $16,045,500 and the weighted average period over which these grants are expected to vest is 3.5 years.
Warrants
During the years ended December 31, 2012 and 2011, the Company issued warrants to investors to purchase 21,347,182 and 2,909,750 shares, respectively, of its common stock.
During the year ended March 31, 2014, the three months ended March 31, 2013 and the year ended December 31, 2012, 225,000, 3,852,214, and 13,259,987 of these warrants were exercised for cash proceeds of approximately $210,000, $3,850,000 and $11,356,000, respectively, and 2,628,003, 3,138,342, and 272,500 of these warrants were exercised through a cashless exercise for issuance of 2,139,577, 2,220,764, and 163,635 shares of common stock, respectively. No warrants were exercised during 2011.
In December 2012, the Company consummated a warrant tender offer to the holders of outstanding warrants to purchase approximately 14.5 million shares of the Company’s common stock. In accordance with the tender offer, for those warrant holders that elected to participate, this resulted in a reduction of the exercise price of the warrants from $1.00 per share to $0.80 per share of common stock in cash, shortened the exercise period of the warrants so that they expired concurrently with the tender offer, and removed the price-based anti-dilution provisions contained in the warrants. The Company completed the tender offer on December 21, 2012, resulting in approximately 9.6 million warrants being exercised for gross proceeds of approximately $7,700,000. In connection with the transaction, the Company recognized an expense for the inducement to exercise the warrants of approximately $1,900,000. The Company also incurred approximately $400,000 in placement agent fees, legal costs, and other related fees, which have been recognized as an offset to the proceeds received from the warrant exercises.
During the year ended March 31, 2014, derivative liability warrants of 1,920,874 were exercised and 6,990,556 of the warrants exercised during the three months ended March 31, 2013 and 13,010,237 of the warrants exercised in 2012 were derivative liabilities and were valued at the settlement date. The warrant liability was reduced to equity at the fair value on the settlement date. See Note 5.
During the twelve months ended March 31, 2014 and the three months ended March 31, 2013, the Company entered into amendment agreements for 269,657 and 601,735, warrants respectively, to purchase common stock which reduced the exercise price of the warrants from $1.00 to between $0.85 and $0.90, which removed the down-round price protection provision of the warrant agreement related to the adjustment of exercise price upon issuance of additional shares of common stock. As a result of the removal of the down-round price protection provision, the warrants were reclassified from liability to equity instruments at their fair value. The Company determined the incremental expense associated with the modification based on the fair value of the awards prior to and subsequent to the modification. The fair value of the awards subsequent to modification was calculated using the Black-Scholes model. The incremental expense associated with the modification of approximately $12,000 and $65,000 was recognized as interest expense for the twelve months ended March 31, 2014 and the three months ended March 31, 2013, respectively.
During the year ended December 31, 2012 the Company entered into four agreements with consultants for services. In connection with the agreements, the Company issued a total of 650,000 warrants to purchase common stock, at prices ranging from $1.70 to $3.24, with lives ranging from two to five years, to be earned over service periods of up to six months. The fair value of the warrants was estimated to be approximately $890,000, which was recognized as a prepaid asset and is being amortized over the term of the consulting agreements. These warrants were classified as equity instruments because they do not contain any anti-dilution provisions. The Black-Scholes model, using volatility rates ranging from 79.8% to 103.8% and risk free interest rate factors ranging from 0.24% to 0.63%, were used to determine the value. The value is being amortized over the term of the agreements. During the year ended March 31, 2014, three months ended March 31, 2013 and the year ended December 31, 2012, the Company recognized approximately $72,000, $261,000, and $556,000, respectively, of expense related to these services. During the year ended March 31, 2014, 348,630 warrants held by consultants were exercised resulting in proceeds to the Company of approximately $891,000. During the three months ended March 31, 2013, 58,220 shares of common stock were issued through a cashless exercise of 100,000 of these warrants.
Additionally, during November 2013 the Company entered into an agreement with a consultant for services. In connection with the agreement, the Company issued 75,000 warrants to purchase common stock, at a price of $7.36, with a life of five years, to be earned over a twelve month service period. The fair value of the warrants was estimated to be approximately $404,000, which was recognized as a prepaid asset and is being amortized over the term of the consulting agreement. These warrants were classified as equity instruments because they do not contain any anti-dilution provisions. The Black-Scholes model, using a volatility rate of 96.90% and a risk-free interest rate factor of 0.60%, was used to determine the value. The Company recognized approximately $163,000 during the year ended March 31, 2014 and for the period from April 19, 2007 (inception) through March 31, 2014, related to these services.

The following table summarizes warrant activity for the year ended March 31, 2014, the three months ended March 31, 2013, and the years ended December 31, 2012, 2011, and 2010:


		Warrants				Weighted-Average
		Warrants				Exercise Price
Balance at December 31, 2010			—				—
Granted			2,909,750			$	1
Expired / Canceled			—				—
Exercised			—				—

Balance at December 31, 2011			2,909,750			$	1
Granted			21,997,182			$	1.04
Exercised			(13,532,487	)		$	0.84

Balance at December 31, 2012			11,374,445			$	1.08
Granted			—				—
Exercised			(7,090,556	)		$	1.01

Balance at March 31, 2013			4,283,889			$	1.17
Granted			112,500			$	7.36
Expired / Canceled			—				—
Exercised			(3,201,633	)			1.16

Balance at March 31, 2014			1,194,756			$	1.79

The warrants outstanding at March 31, 2014 are immediately exercisable at prices between $0.85 and $7.36 per share, and have a weighted average remaining term of approximately 2.55 years.
Common stock reserved for future issuance
Common stock reserved for future issuance consisted of the following at March 31, 2014:


Common stock warrants outstanding			1,194,756
Common stock options outstanding under the 2008 Plan			672,192
Common stock options outstanding and reserved under the 2012 Plan			9,534,989

Total			11,401,937

Preferred stock
The Company is authorized to issue 25,000,000 shares of preferred stock. There are no shares of preferred stock currently outstanding, and the Company has no present plans to issue shares of preferred stock.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Mar. 31, 2014
Commitments And Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	8. Commitments and Contingencies
	Operating leases
	The Company leases office and laboratory space under a non-cancelable operating lease which was entered into in February 2012 and amended in December 2013, with the future minimum lease payments from the lease included below. The Company records rent expense on a straight-line basis over the life of the lease and records the excess of expense over the amounts paid as deferred rent. Deferred rent is included in accrued expenses in the consolidated balance sheets.
	Rent expense was approximately $561,500, $105,500, $60,200, $325,600, and $145,200 for the year ended March 31, 2014, the three months ended March 31, 2013 and 2012, and the years ended December 31, 2012, and 2011, respectively. Rent expense was approximately $1,317,200 for the period from April 19, 2007 (inception) through March 31, 2014.
	On February 27, 2012, the Company entered into a facilities lease at 6275 Nancy Ridge Drive (the “Original Lease”), San Diego, CA 92121, with occupancy as of July 15, 2012. The base rent under the lease was approximately $38,800 per month with 3% annual escalators. The lease term was 48 months with an option for the Company to extend the lease at the end of the lease term.

	On December 5, 2013, the Company entered into a First Amendment (the “Amendment”) to the Original Lease, together with the Amendment, (the “Amended Lease”). Pursuant to the Amendment, the Company expanded the size of its facility by approximately 15,268 square feet (the “Expansion Premises”) from approximately 15,539 square feet (the “Original Premises”) for a total of approximately 30,807 square feet. The Amended Lease provides for base rent (i) on the Original Premises to continue at approximately $38,800 per month, with annual escalators, until August 1, 2016, at which point the base rent shall be payable at the same rate per rentable square foot as the Expansion Premises and (ii) on the Expansion Premises of approximately $38,934 per month, with 3% annual escalators, not to commence until two months after the earlier of (A) the date that the landlord delivers possession of the Expansion Premises to the Company with the work in the Expansion Lab Premises (as defined in the Amendment) substantially complete and (B) the date the landlord could have delivered the Expansion Premises with the work in the Expansion Lab Premises (as defined in the Amendment) substantially complete but for certain delays of the Company. Additionally, the Company has a right of first refusal on adjacent additional premises of approximately 14,500 square feet. The term of the Amended Lease expires on the seven-year anniversary of the earlier of (A) the date that the landlord delivers possession of the Expansion Premises to the Company and (B) the date the landlord could have delivered the Expansion Premises but for certain delays of the Company (the “Expansion Premises Commencement Date”). The target Expansion Premises Commencement Date is September 1, 2014. The Company also has the option to terminate the Amended Lease on the 5-year anniversary of the Expansion Premises Commencement Date. The Company intends for the Expansion Premises to contain office, laboratory, and clean room areas.
	Future minimum rental payments required under operating leases that have initial or remaining non-cancelable lease terms in excess of one year as of March 31, 2014, are as follows (in thousands):


	Fiscal year ended March 31, 2015	$	766
	Fiscal year ended March 31, 2016		981
	Fiscal year ended March 31, 2017		986
	Fiscal year ended March 31, 2018		1,004
	Fiscal year ended March 31, 2019		1,034
	Thereafter		2,439

	Total	$	7,210

	Capital leases
	During 2012, the Company entered into an agreement to lease certain laboratory equipment under a non-cancelable capital lease, which is included in fixed assets as follows (in thousands):


	March 31, 2014
	Lab equipment	$	34
	Less accumulated depreciation		(11	)

	Net book value	$	23

	Depreciation expense related to the capital lease obligation was approximately $6,800, $1,700 and $2,900 for the year ended March 31, 2014, the three months ended March 31, 2013 and the year ended December 31, 2012, respectively.

	Future minimum capital lease payments at March 31, 2014 are as follows (in thousands):


	Fiscal year ended March 31, 2015	$	11
	Fiscal year ended March 31, 2016		4

	Total minimum lease payments		15
	Amount representing interest		—
	Present value of minimum lease payments		15
	Less current portion		(10	)

	Long term portion	$	5

	Legal Matters
	In addition to commitments and obligations in the ordinary course of business, the Company is subject to various claims and pending and potential legal actions arising out of the normal conduct of its business. The Company assesses contingencies to determine the degree of probability and range of possible loss for potential accrual in its financial statements. An estimated loss contingency is accrued in its financial statements if it is probable that a liability has been incurred and the amount of the loss can be reasonably estimated. Because litigation is inherently unpredictable and unfavorable resolutions could occur, assessing litigation contingencies is highly subjective and requires judgments about future events. When evaluating contingencies, the Company may be unable to provide a meaningful estimate due to a number of factors, including the procedural status of the matter in question, the presence of complex or novel legal theories, and/or the ongoing discovery and development of information important to the matters. In addition, damage amounts claimed in litigation against it may be unsupported, exaggerated or unrelated to possible outcomes, and as such are not meaningful indicators of its potential liability. The Company regularly reviews contingencies to determine the adequacy of its accruals and related disclosures. The amount of ultimate loss may differ from these estimates. It is possible that cash flows or results of operations could be materially affected in any particular period by the unfavorable resolution of one or more of these contingencies. Whether any losses finally determined in any claim, action, investigation or proceeding could reasonably have a material effect on the Company’s business, financial condition, results of operations or cash flows will depend on a number of variables, including: the timing and amount of such losses; the structure and type of any remedies; the monetary significance of any such losses, damages or remedies may have on our consolidated financial statements; and the unique facts and circumstances of the particular matter that may give rise to additional factors.
	Spencer Trask Matter. On June 28, 2013, the Company filed a lawsuit for declaratory relief in the Supreme Court for the State of New York (case # 652305/2013) against Spencer Trask Ventures, Inc. (“STV” or “Spencer Trask”) in connection with a Warrant Solicitation Agency Agreement (the “WSAA”) that the Company entered into with STV in February 2013 (the “New York Action”). In the New York Action, the Company is seeking a declaration that the WSAA remains a valid and enforceable agreement. Over the course of several weeks in February 2013, Organovo and STV, through their respective attorneys, negotiated the WSAA pursuant to which the Company engaged STV as the Company’s warrant solicitation agent in connection with the Company’s efforts to solicit the exercise of outstanding Organovo warrants during the first quarter of 2013. STV’s President signed the WSAA on behalf of STV, and the Company’s CEO executed the agreement on behalf of Organovo. Spencer Trask provided services to the Company pursuant to the WSAA, and the Company has paid STV for those services.
	The Company’s dispute with Spencer Trask arose in March 2013 after the Company approached Spencer Trask about exercising its outstanding warrants to help the Company qualify for up-listing its common stock on the NYSE MKT. Previously, Spencer Trask had not asserted any claims for additional compensation as a result of the warrant tender offer the Company completed in December 2012. In March 2013, the Company received two demand letters from STV, and a demand for arbitration notice in June 2013. In the first demand letter, STV alleges that it is entitled to compensation (including a cash fee and warrants to purchase common stock) as a result of the warrant tender offer the Company completed in December 2012 and as a result of the notice of warrant redemption the Company completed in March 2013. In the second letter, STV alleges it is entitled to damages because the Company allegedly violated confidentiality provisions in the Placement Agency Agreement (the “PAA”) the Company had previously entered into with STV in December 2012 in connection with the private placement financings the Company completed in February and March 2012 (the “Private Placements”), by contacting the warrant holders who participated in the warrant tender offer. In response, on June 28, 2013, the Company filed a lawsuit for declaratory relief in the Supreme Court for the State of New York against STV. The Company’s tender offer was made to warrant holders of record relating to warrants already owned by them and whose identity was public information via a Registration Statement on Form S-1 the Company was required to file to register the resale of the shares underlying their warrants. For these and other reasons, including applicability of the WSAA, the Company believes STV is not entitled to compensation under the PAA and there was no violation of confidentiality. The Company received notice on August 5, 2013 that STV had filed its arbitration demand with the arbitrator (the “Arbitration”). In July, 2013, the Company filed a motion to stay the arbitration pending determination of the New York Action. In January 2014, the New York Court stayed the New York Action, finding that the arbitrator should determine in the first instance which disputes between the Company and Spencer Trask should proceed in the Arbitration and which disputes between the Company and Spencer Trask should proceed in the New York Court. The parties are proceeding in the Arbitration and the Company has reserved its right to file a summary disposition motion with regard to the proper venue for its claims under the WSAA. The Arbitration is scheduled to commence on March 2, 2015.
	The Company believes that the assertions made against it by STV are without merit and the Company intends to continue to vigorously defend against the claims made by STV. The Company has not established a loss contingency accrual for these claims because any potential liability is not probable or estimable. Nonetheless, an unfavorable resolution of these claims could have a material adverse effect on the Company’s business, liquidity or financial condition in the reporting period in which such resolution occurs.
	Other Legal Matters. In addition to the matter described above, the Company is subject to normal and routine litigation in the ordinary course of business. The Company has not accrued any loss contingencies for such matters. The Company intends to defend itself in any such matters and does not currently believe that the outcome of such matters will have a material adverse effect on its business, liquidity or financial position.

Licensing_Agreements_and_Resea

Licensing Agreements and Research Contracts	12 Months Ended
Licensing Agreements and Research Contracts	Mar. 31, 2014
Text Block [Abstract]	'
Licensing Agreements and Research Contracts	'
	9. Licensing Agreements and Research Contracts
	University of Missouri
	On March 24, 2009, the Company entered into a license agreement with the Curators of the University of Missouri to in-license certain technology and intellectual property relating to self-assembling cell aggregates and to intermediate cellular units. The Company received the exclusive worldwide rights to commercialize products comprising this technology for all fields of use. The Company paid to the University of Missouri a nonrefundable license fee of $25,000 and has committed to reimburse the University of Missouri for certain prior and future patent costs. Each year the Company is required to pay the University of Missouri royalties ranging from 1% to 3% of net sales depending on the level of net sales achieved by the Company each year. A minimum annual royalty of $25,000 is due beginning two years after the calendar year of the first commercial sale and is credited to sales royalties. The license agreement terminates upon expiration of the patents licensed and is subject to certain conditions as defined in the license agreement, which are expected to expire after 2029. The $25,000 license fee is included in Other Assets in the accompanying balance sheets and is being amortized over the life of the related patent.
	On March 12, 2010, the Company entered into a license agreement with the Curators of the University of Missouri to in-license certain technology and intellectual property relating to engineered biological nerve grafts. The Company received the exclusive worldwide rights to commercialize products comprising this technology for all fields of use. The Company paid to University of Missouri a nonrefundable license fee of $5,000 and has committed to reimburse the University of Missouri for certain prior and future patent costs. In 2012 and 2011, the Company paid the University of Missouri approximately $193,500 and $23,800, respectively, for prior patent costs relating to the license agreements with the University of Missouri. No payments were made during the year ended March 31, 2014 or the three months ended March 31, 2013. Each year the Company is required to pay the University of Missouri royalties ranging from 1% to 3% of net sales depending on the level of net sales achieved by the Company each year. A minimum annual royalty of $5,000 is due beginning two years after the calendar year of the first commercial sale and is credited to sales royalties. An additional royalty of $12,500 is due if there are no net sales within five years from the effective date of the license. The license agreement terminates upon expiration of the patents licensed and is subject to certain conditions as defined in the license agreement. The $5,000 license fee is included in Other Assets and is being amortized over the life of the related patent.
	Clemson University
	On May 2, 2011, the Company entered into a license agreement with Clemson University Research Foundation to in-license certain technology and intellectual property relating to ink-jet printing of viable cells. The Company received the exclusive worldwide rights to commercialize products comprising this technology for all fields of use. The Company agreed to pay Clemson University a nonrefundable license fee of $32,500, as well as an additional $32,500 to reimburse Clemson University for certain prior and future patent costs. These fees, totaling $65,000, are included in Other Assets and are being amortized over the life of the related patent. Each year the Company is required to pay the University royalties ranging from 1.5% to 3% of net sales depending on the level of net sales reached each year and minimum annual fees ranging from $20,000 to $40,000. Specific terms of the royalty and license agreements are confidential. The license agreement terminates upon expiration of the patents licensed, which is expected to expire in May 2024, and is subject to certain conditions as defined in the license agreement.
	No royalty payments have been made under the above license agreements as of March 31, 2014. Approximately $4,000 is due to the University of Missouri relating to the first commercial sale. Annual royalty payments of $30,000 and $20,000 will be due to the University of Missouri and Clemson University, respectively, in calendar 2014 per the terms of the respective license agreements.
	Becton Dickinson
	In February of 2013, the Company purchased the exclusive rights to intellectual property relating to perfusion bioreactors for culturing cells from Becton Dickinson and Company for $18,500. This fee is included in Other Assets and is being amortized over the life of the related patent. This patent represents the acquisition of bioreactor technology for the support of our 3D tissues for use in drug discovery and development. No future royalties or milestone payments are owed to Becton Dickinson and Company for this patent.
	Capitalized license fees consisted of the following (in thousands):


		March 31,			March 31,			December 31,
		2014			2013			2012
	License fees	$	114		$	114		$	95
	Less accumulated amortization		(25	)		(17	)		(15	)

	License fees, net	$	89		$	97		$	80

	Amortization expense of licenses was approximately $8,500, $2,000, $1,700, $7,000, $5,200, and $25,200 for the year ended March 31, 2014, the three months ended March 31, 2013 and 2012, the years ended December 31, 2012 and 2011, and the period from April 19, 2007 (inception) through March 31, 2014, respectively. At March 31, 2014, the weighted average remaining amortization period for all licenses was approximately 11 years. The annual amortization expense of licenses for the next five years is estimated to be approximately $8,500 per year.

Income_Taxes

Income Taxes	12 Months Ended
Income Taxes	Mar. 31, 2014
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	10. Income Taxes
	Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Significant components of the Company’s net deferred tax assets are as follows as of March 31, 2014, March 31, 2013, and December 31, 2012 (in thousands):


		March 31,			March 31,			December 31,
		2014			2013			2012
	Deferred tax assets:
	Net operating loss carry forwards	$	—		$	—		$	—
	Research and development credits		—			—			—
	Depreciation and amortization		22			(1	)		(2	)
	Accrued expenses and reserves		280			224			290
	Stock compensation		1,941			743			562
	Other, net		1			1			—

	Total deferred tax assets		2,244			967			850
	Valuation allowance		(2,244	)		(967	)		(850	)

		$	—		$	—		$	—
	A full valuation allowance has been established to offset the deferred tax assets as management cannot conclude that realization of such assets is more likely than not. Under the Internal Revenue Code (“IRC”) Sections 382 and 383, annual use of our net operating loss and research tax credit carryforwards to offset taxable income may be limited based on cumulative changes in ownership. We have not completed an analysis to determine whether any such limitations have been triggered as of March 31, 2014. Until this analysis is completed, we have removed the deferred tax assets related to net operating losses and research credits from our deferred tax asset schedule. The valuation allowance increased by approximately $1,277,000 and increased by approximately $117,000 for the year ended March 31, 2014 and the three months ended March 31, 2013, respectively.
	The Company had federal and state net operating loss carryforwards of approximately $34,838,000 and $34,833,000 at March 31, 2014, respectively. The federal and state net operating loss carryforwards will begin expiring in 2028, unless previously utilized. The net operating loss carryforwards included approximately $3,389,000 of windfall tax benefits related to stock compensation that will be recorded as an increase to additional paid in capital.
	The Company had federal and state research tax credit carry forwards of approximately $450,000 and $548,000 at March 31, 2014, respectively. The federal research tax credit carryforwards begin expiring in 2028. The state research tax credit carryforwards do not expire.
	In 2009 the Company adopted the accounting guidance for uncertainty in income taxes pursuant to ASC 740-10. The adoption of this guidance did not have a material impact on the Company’s consolidated financial statements. The Company did not record any accruals for income tax accounting uncertainties for the year ended March 31, 2014.
	The Company’s policy is to recognize interest and penalties that would be assessed in relation to the settlement value of unrecognized tax benefits as a component of income tax expense. The Company did not accrue either interest or penalties from inception through March 31, 2014.
	The Company does not have any unrecognized tax benefits that will significantly decrease or increase within 12 months of March 31, 2014.
	The Company is subject to tax in the United States and in the state of California. As of March 31, 2014, the Company’s tax years from inception are subject to examination by the tax authorities. The Company is not currently under examination by any U.S. federal or state jurisdictions.

Concentrations

Concentrations	12 Months Ended
Concentrations	Mar. 31, 2014
Risks And Uncertainties [Abstract]	'
Concentrations	'
	11. Concentrations
	Credit risk
	Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of temporary cash investments. The Company maintains cash balances at various financial institutions primarily located in San Diego. Accounts at these institutions are secured by the Federal Deposit Insurance Corporation. At times, balances may exceed federally insured limits. The Company has not experienced losses in such accounts, and management believes that the Company is not exposed to any significant credit risk with respect to its cash and cash equivalents.

Description_of_Business_and_Su1

Description of Business and Summary of Significant Accounting Policies (Policies)

12 Months Ended

Mar. 31, 2014

Accounting Policies [Abstract]

Nature of Operations and Basis of Presentation

Nature of operations and basis of presentation

Reverse Merger Transaction

Reverse merger transaction

The cash transaction costs related to the Merger were approximately $2.1 million.

Liquidity

In August of 2013, the Company raised net proceeds of approximately $43.4 million through the sale of 10,350,000 shares of its common stock in a public offering (see Note 7).

Use of Estimates

Use of estimates

Financial Instruments

Financial instruments

Cash and Cash Equivalents

Cash and cash equivalents

The Company considers all highly liquid investments with original maturities of 90 days or less to be cash equivalents.

Derivative Financial Instruments

Derivative financial instruments

The Company does not use derivative instruments to hedge exposures to cash flow, market or foreign currency.

Restricted Cash

Restricted cash

Grant Receivable

Grant receivable

Inventory

Fixed Assets and Depreciation

Fixed assets and depreciation

Impairment of Long-Lived Assets

Impairment of long-lived assets

Fair Value Measurement

Fair value measurement

•

Level 1 — Quoted prices in active markets for identical assets or liabilities.

•

Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

The estimated fair values of the liabilities measured on a recurring basis are as follows:

Fair Value Measurements at March 31, 2014, March 31, 2013, and December 31, 2012 (in thousands):

Balance at

Quoted

Significant

March 31,

Prices in

Other

2014

Active

Observable

Unobservable

Markets

Inputs

(Level 1)

(Level 2)

(Level 3)

Warrant liability

377

—

377

Balance at

Quoted

Significant

March 31,

Prices in

Other

2013

Active

Observable

Unobservable

Markets

Inputs

(Level 1)

(Level 2)

(Level 3)

Warrant liability

6,898

—

6,898

Balance at

Quoted

Significant

December 31,

Prices in

Other

2012

Active

Observable

Unobservable

Markets

Inputs

(Level 1)

(Level 2)

(Level 3)

Warrant liability

20,619

—

20,619

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

Warrant

Derivative

Liability

(in thousands)

Balance at December 31, 2011

1,267

Issuances

32,742

Adjustments to estimated fair value

9,931

Warrant liability removal due to settlements

(23,321

)

Balance at December 31, 2012

20,619

Issuances

—

Adjustments to estimated fair value

12,034

Warrant liability removal due to settlements

(23,869

)

Warrant liability reclassified to equity

(1,886

)

Balance at March 31, 2013

6,898

Issuances

—

Adjustments to estimated fair value

5,120

Warrant liability removal due to settlements

(10,874

)

Warrant liability reclassified to equity

(767

)

Balance at March 31, 2014

377

Research and Development

Research and development

Income Taxes

Income taxes

Revenue Recognition

Revenue recognition

Product Revenue

Research and Development Revenue Under Collaborative Agreements

Revenue Arrangements with Multiple Deliverables

NIH and U.S. Treasury Grant Revenues

Stock-Based Compensation

Stock-based compensation

Comprehensive Income (Loss)

Comprehensive income (loss)

Net Loss per Share

Net loss per share

Reclassifications

Description_of_Business_and_Su2

Description of Business and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Estimated Fair Values of Liabilities Measured on Recurring Basis	'
	The estimated fair values of the liabilities measured on a recurring basis are as follows:


		Fair Value Measurements at March 31, 2014, March 31, 2013, and December 31, 2012 (in thousands):
		Balance at			Quoted		Significant		Significant
		March 31,			Prices in		Other		Other
		2014			Active		Observable		Unobservable
					Markets		Inputs		Inputs
					(Level 1)		(Level 2)		(Level 3)
	Warrant liability	$	377		$	—	$	—	$	377

		Balance at			Quoted		Significant		Significant
		March 31,			Prices in		Other		Other
		2013			Active		Observable		Unobservable
					Markets		Inputs		Inputs
					(Level 1)		(Level 2)		(Level 3)
	Warrant liability	$	6,898		$	—	$	—	$	6,898

		Balance at			Quoted		Significant		Significant
		December 31,			Prices in		Other		Other
		2012			Active		Observable		Unobservable
					Markets		Inputs		Inputs
					(Level 1)		(Level 2)		(Level 3)
	Warrant liability	$	20,619		$	—	$	—	$	20,619
Activity for Liabilities Measured at Estimated Fair Value Using Unobservable Inputs	'
	The following table presents the activity for liabilities measured at estimated fair value using unobservable inputs for the year ended December 2012, the three months ended March 31, 2013, and the year ended March 31, 2014:
	Fair Value Measurements Using Significant Unobservable Inputs (Level 3)


		Warrant
		Derivative
		Liability
		(in thousands)
	Balance at December 31, 2011	$	1,267
	Issuances	$	32,742
	Adjustments to estimated fair value	$	9,931
	Warrant liability removal due to settlements	$	(23,321	)

	Balance at December 31, 2012	$	20,619
	Issuances	$	—
	Adjustments to estimated fair value	$	12,034
	Warrant liability removal due to settlements	$	(23,869	)
	Warrant liability reclassified to equity	$	(1,886	)

	Balance at March 31, 2013	$	6,898
	Issuances	$	—
	Adjustments to estimated fair value	$	5,120
	Warrant liability removal due to settlements	$	(10,874	)
	Warrant liability reclassified to equity	$	(767	)

	Balance at March 31, 2014	$	377

Fixed_Assets_Tables

Fixed Assets (Tables)	12 Months Ended
Fixed Assets (Tables)	Mar. 31, 2014
Property Plant And Equipment [Abstract]	'
Schedule of Fixed Assets	'
	Fixed assets consisted of the following (in thousands):


		March 31,			March 31,			December 31,
		2014			2013			2012
	Laboratory equipment	$	1,207		$	1,168		$	759
	Computer software and equipment		191			114			114
	Furniture and fixtures		33			33			33

			1,431			1,315			906

	Less accumulated depreciation and amortization		(574	)		(270	)		(192	)

		$	857		$	1,045		$	714

Accrued_Expenses_Tables

Accrued Expenses (Tables)	12 Months Ended
Accrued Expenses (Tables)	Mar. 31, 2014
Payables And Accruals [Abstract]	'
Summary of Accrued Expenses	'
	Accrued expenses consisted of the following (in thousands):


		March 31,		March 31,		December 31,
		2014		2013		2012
	Accrued compensation	$	505	$	386	$	720
	Deferred rent		345		270		188
	Accrued legal and professional fees		283		53		—
	Other accrued expenses		34		71		73

		$	1,167	$	780	$	981

Derivative_Liability_Tables

Derivative Liability (Tables)	12 Months Ended
Derivative Liability (Tables)	Mar. 31, 2014
Derivative Instruments And Hedging Activities Disclosure [Abstract]	'
Assumptions Used to Value Derivative Liabilities at Closing Dates of Private Placements	'
	The derivative liabilities were valued at the closing dates of the Private Placement and the end of each reporting period using a Monte Carlo valuation model with the following assumptions:


		March 31,			March 31,			December 31,
		2014			2013			2012
	Closing price per share of common stock	$	7.64		$	3.68		$	2.6
	Exercise price per share	$	1		$	1		$	1
	Expected volatility		76.5	%		88.8	%		92.9	%
	Risk-free interest rate		0.9	%		0.57	%		0.54	%
	Dividend yield		—			—			—
	Remaining expected term of underlying securities (years)		2.96			3.88			4.16

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	12 Months Ended
Stockholders' Equity (Tables)	Mar. 31, 2014
Equity [Abstract]	'
Summary of Company's Restricted Stock Award Activity	'
	A summary of the Company’s restricted stock award activity is as follows:


		Number of
		Shares
	Unvested at December 31, 2007		—
	Granted		12,627,697
	Vested		(65,211	)
	Canceled / forfeited		—

	Unvested at December 31, 2008		12,562,486
	Granted		130,422
	Vested		(5,373,004	)
	Canceled / forfeited		—

	Unvested at December 31, 2009		7,319,904
	Granted		219,369
	Vested		(3,256,191	)
	Canceled / forfeited		—

	Unvested at December 31, 2010		4,283,082
	Granted		61,406
	Vested		(3,233,193	)
	Canceled / forfeited		—

	Unvested at December 31, 2011		1,111,295
	Granted		1,380,000
	Vested		(1,233,409	)
	Canceled / forfeited		(95,842	)

	Unvested at December 31, 2012		1,162,044
	Granted		55,000
	Vested		(221,302	)
	Canceled / forfeited		(10,000	)

	Unvested at March 31, 2013		985,742
	Granted		60,000
	Vested		(472,247	)
	Canceled / forfeited		—

	Unvested at March 31, 2014		573,495

Summary of Stock Option Activity	'
	The following table summarizes stock option activity for 2010 through March 31, 2014:


		Options			Weighted-			Aggregate
		Outstanding			Average			Intrinsic
					Exercise Price			Value
	Outstanding at December 31, 2010		—			—			—
	Options granted		896,256		$	0.08
	Options canceled		—			—
	Options exercised		—			—

	Outstanding at December 31, 2011		896,256		$	0.08			—
	Options granted		2,023,394		$	1.95
	Options canceled		(5,000	)	$	2.25
	Options exercised		(224,064	)	$	0.08		$	564,641

	Outstanding at December 31, 2012		2,690,586		$	1.48		$	3,041,476
	Options granted		927,981		$	3.93
	Options canceled		—			—
	Options exercised		—			—			—

	Outstanding at March 31, 2013		3,618,567		$	2.11		$	5,909,154
	Options granted		2,519,572		$	8.63
	Options canceled		(18,455	)		3.31
	Options exercised		(183,796	)		2.19		$	1,002,419

	Outstanding at March 31, 2014		5,935,888		$	4.87		$	20,482,823

	Vested and Exercisable at March 31, 2014		1,546,377		$	2.73		$	7,733,041

Fair Value of Employee Stock Options	'
	The fair value of stock options was estimated at the grant date using the following weighted average assumptions:


		Year Ended			Three Months			Year Ended
		March 31, 2014			Ended			December 31, 2012
					March 31, 2013
	Dividend yield		—			—			—
	Volatility		78.22	%		96.83	%		96.22	%
	Risk-free interest rate		1.32	%		1.19	%		0.89	%
	Expected life of options		6.00 years			6.07 years			6.05 years
	Weighted average grant date fair value	$	5.92		$	3.04		$	1.5
Summary of Warrant Activity	'
	The following table summarizes warrant activity for the year ended March 31, 2014, the three months ended March 31, 2013, and the years ended December 31, 2012, 2011, and 2010:


		Warrants			Weighted-Average
		Warrants			Exercise Price
	Balance at December 31, 2010		—			—
	Granted		2,909,750		$	1
	Expired / Canceled		—			—
	Exercised		—			—

	Balance at December 31, 2011		2,909,750		$	1
	Granted		21,997,182		$	1.04
	Exercised		(13,532,487	)	$	0.84

	Balance at December 31, 2012		11,374,445		$	1.08
	Granted		—			—
	Exercised		(7,090,556	)	$	1.01

	Balance at March 31, 2013		4,283,889		$	1.17
	Granted		112,500		$	7.36
	Expired / Canceled		—			—
	Exercised		(3,201,633	)		1.16

	Balance at March 31, 2014		1,194,756		$	1.79

Common Stock Reserved for Future Issuance	'
	Common stock reserved for future issuance consisted of the following at March 31, 2014:


	Common stock warrants outstanding		1,194,756
	Common stock options outstanding under the 2008 Plan		672,192
	Common stock options outstanding and reserved under the 2012 Plan		9,534,989

	Total		11,401,937

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
Commitments and Contingencies (Tables)	Mar. 31, 2014
Commitments And Contingencies Disclosure [Abstract]	'
Future Minimum Rental Payments Required under Operating Leases that have Initial or Remaining Non-Cancelable Lease Terms in Excess of One Year	'
	Future minimum rental payments required under operating leases that have initial or remaining non-cancelable lease terms in excess of one year as of March 31, 2014, are as follows (in thousands):


	Fiscal year ended March 31, 2015	$	766
	Fiscal year ended March 31, 2016		981
	Fiscal year ended March 31, 2017		986
	Fiscal year ended March 31, 2018		1,004
	Fiscal year ended March 31, 2019		1,034
	Thereafter		2,439

	Total	$	7,210

Agreement to Lease Certain Laboratory Equipment under Non-Cancelable Capital Lease, Which is Included in Fixed Assets	'
	During 2012, the Company entered into an agreement to lease certain laboratory equipment under a non-cancelable capital lease, which is included in fixed assets as follows (in thousands):


	March 31, 2014
	Lab equipment	$	34
	Less accumulated depreciation		(11	)

	Net book value	$	23

Future Minimum Capital Lease Payments	'
	Future minimum capital lease payments at March 31, 2014 are as follows (in thousands):


	Fiscal year ended March 31, 2015	$	11
	Fiscal year ended March 31, 2016		4

	Total minimum lease payments		15
	Amount representing interest		—
	Present value of minimum lease payments		15
	Less current portion		(10	)

	Long term portion	$	5

Licensing_Agreements_and_Resea1

Licensing Agreements and Research Contracts (Tables)	12 Months Ended
Licensing Agreements and Research Contracts (Tables)	Mar. 31, 2014
Text Block [Abstract]	'
Schedule of Capitalized License Fees	'
	Capitalized license fees consisted of the following (in thousands):


		March 31,			March 31,			December 31,
		2014			2013			2012
	License fees	$	114		$	114		$	95
	Less accumulated amortization		(25	)		(17	)		(15	)

	License fees, net	$	89		$	97		$	80

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
Income Taxes (Tables)	Mar. 31, 2014
Income Tax Disclosure [Abstract]	'
Summary of Net Deferred Tax Assets	'
	Significant components of the Company’s net deferred tax assets are as follows as of March 31, 2014, March 31, 2013, and December 31, 2012 (in thousands):


		March 31,			March 31,			December 31,
		2014			2013			2012
	Deferred tax assets:
	Net operating loss carry forwards	$	—		$	—		$	—
	Research and development credits		—			—			—
	Depreciation and amortization		22			(1	)		(2	)
	Accrued expenses and reserves		280			224			290
	Stock compensation		1,941			743			562
	Other, net		1			1			—

	Total deferred tax assets		2,244			967			850
	Valuation allowance		(2,244	)		(967	)		(850	)

		$	—		$	—		$	—

Description_of_Business_and_Su3

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

1 Months Ended

2 Months Ended

3 Months Ended

12 Months Ended

47 Months Ended

83 Months Ended

12 Months Ended

1 Months Ended

0 Months Ended

9 Months Ended

0 Months Ended

Aug. 31, 2013

Aug. 31, 2011

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2014

Feb. 08, 2012

Feb. 07, 2012

Feb. 08, 2012

Dec. 31, 2011

Mar. 31, 2014

Nov. 30, 2013

Mar. 16, 2012

Feb. 29, 2012

Feb. 08, 2012

Dec. 31, 2013

Feb. 08, 2012

Convertible Notes Payable [Member]

Maximum [Member]

Equity Distribution Agreement [Member]

Merger transition [Member]

Maximum [Member]

Private_placement

Outstanding Principal Assumed On Acquisition [Member]

Accrued Interest Assumed On Acquisition [Member]

Significant Accounting Policies Related To Business Acquisition Revenue Recognition And Earnings Per Share [Line Items]

Common stock, par value

$0.00

Common stock conversion basis

'1 for 1 basis

Former security holders common stock voting interest

75.00%

Company's stockholders retained voting interest

25.00%

Number of private placement transactions

Total gross proceeds of approximately

$6,900,000

$1,800,000

$5,000,000

Proceeds from issuance of convertible notes payable

740,000

2,543,000

2,390,000

4,630,000

1,500,000

Convertible notes, interest rate

20.00%

6.00%

10.00%

Convertible notes converted into shares of common stock

1,500,000

25,387

Accrued interest

25,000

460,000

25,387

Cash transaction costs related to the Merger approximately

2,100,000

Accumulated deficit

66,365,000

92,213,000

50,245,000

92,213,000

Cash flow from operations

-15,561,000

Net proceeds to company from offering

43,400,000

Sale of common stock in a public offering

10,350,000

334,412

Number of shares to be offered and sold in equity distribution agreement

4,000,000

Value of shares sold under equity distribution agreement

$3,500,000

Description_of_Business_and_Su4

Description of Business and Summary of Significant Accounting Policies - Additional Information I (Detail) (USD $)

3 Months Ended

12 Months Ended

83 Months Ended

12 Months Ended

1 Months Ended

3 Months Ended

12 Months Ended

83 Months Ended

1 Months Ended

12 Months Ended

83 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

37 Months Ended

83 Months Ended

1 Months Ended

12 Months Ended

83 Months Ended

9 Months Ended

12 Months Ended

Share data in Millions, unless otherwise specified

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Oct. 31, 2011

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2014

Dec. 31, 2010

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2014

Dec. 31, 2010

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2012

Mar. 31, 2014

Aug. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

sqft

Third party [Member]

Research and Development Services [Member]

12 month research contract agreement [Member]

U.S. Treasury [Member]

NHLBI [Member]

Private, not-for-profit organization [Member]

Maximum [Member]

Minimum [Member]

Grants

Significant Accounting Policies Related To Business Acquisition Revenue Recognition And Earnings Per Share [Line Items]

Maturity of highly liquid investment

'90 days

Restricted cash

$88,000

$79,000

$88,000

$79,000

Restricted cash held in certificates of deposit

38,300

78,800

38,300

78,800

Increase in rented area

15,268

Additional restricted cash

50,000

Allowance for doubtful amounts

Inventory of raw materials, net of reserves

88,000

63,000

104,000

63,000

Inventory of finished goods

196,000

Inventory of work-in-progress

60,000

Obsolete inventory reserve

31,000

Estimated useful life of the fixed assets

'The estimated useful lives of the fixed assets range between two and five years.

Useful life of fixed assets, range

'5 years

'2 years

Impairment of long-lived assets

Deferred revenue related to its collaborative research programs

53,000

13,000

62,000

17,000

Term of research contract agreement with third party

'12 months

Research and development services on a fixed-fee basis

1,365,000

600,000

Total revenue recognized from inception on the contract

215,000

120,000

379,000

1,197,000

969,000

3,442,000

1,405,000

150,000

450,000

600,000

Initial payment to company from agreement

239,000

Remaining payments expected to occur over

'21 months

Fee for additional research and development services

135,000

40,000

Total potential contract value

1,500,000

1,405,000

Maximum amendment extended period remaining for payment of additional research and development services

'28 months

Revenue related to research contract

97,000

120,000

184,000

885,000

239,000

Number of grants issued

Revenue recognized under grants

117,000

131,000

162,000

57,000

1,074,000

397,000

117,000

12,000

162,000

57,000

558,000

251,700

119,000

Dilutive effect

Total common stock equivalents excluded from computing diluted net loss per share

8.9

25.8

7.7

15.2

6.4

Description_of_Business_and_Su5

Description of Business and Summary of Significant Accounting Policies - Estimated Fair Values of Liabilities Measured on Recurring Basis (Detail) (Warrants [Member], USD $)	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Fair Value, Measurements, Recurring [Member]	'	'	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'	'	'
Warrant liability	$377	$6,898	$20,619	'
Quoted Prices in Active Markets (Level 1) [Member] \| Fair Value, Measurements, Recurring [Member]	'	'	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'	'	'
Warrant liability	'	'	'	'
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value, Measurements, Recurring [Member]	'	'	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'	'	'
Warrant liability	'	'	'	'
Significant Other Unobservable Inputs (Level 3) [Member]	'	'	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'	'	'
Warrant liability	377	6,898	20,619	1,267
Significant Other Unobservable Inputs (Level 3) [Member] \| Fair Value, Measurements, Recurring [Member]	'	'	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'	'	'
Warrant liability	$377	$6,898	$20,619	'

Description_of_Business_and_Su6

Description of Business and Summary of Significant Accounting Policies - Activity for Liabilities Measured at Estimated Fair Value Using Unobservable Inputs (Detail) (USD $)	3 Months Ended		12 Months Ended			83 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2011	Mar. 31, 2014
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'	'	'	'	'
Adjustments to estimated fair value	$12,034,000	$13,506,000	$5,120,000	$9,931,000	$7,000	$27,092,000
Warrant liability reclassified to equity	-1,886,000	'	-767,000	'	'	'
Significant Other Unobservable Inputs (Level 3) [Member] \| Warrants [Member]	'	'	'	'	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'	'	'	'	'
Warrant Derivative Liability, Beginning balance	20,619,000	1,267,000	6,898,000	1,267,000	'	'
Issuances	'	'	'	32,742,000	'	'
Adjustments to estimated fair value	12,034,000	'	5,120,000	9,931,000	'	'
Warrant liability removal due to settlements	-23,869,000	'	-10,874,000	-23,321,000	'	'
Warrant liability reclassified to equity	-1,886,000	'	-767,000	'	'	'
Warrant Derivative Liability, Ending balance	$6,898,000	'	$377,000	$20,619,000	'	$377,000

Fixed_Assets_Schedule_of_Fixed

Fixed Assets - Schedule of Fixed Assets (Detail) (USD $)	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
Property Plant And Equipment Net [Abstract]	'	'	'
Laboratory equipment	$1,207	$1,168	$759
Computer software and equipment	191	114	114
Furniture and fixtures	33	33	33
Fixed assets, gross	1,431	1,315	906
Less accumulated depreciation and amortization	-574	-270	-192
Fixed assets, net	$857	$1,045	$714

Fixed_Assets_Additional_Inform

Fixed Assets - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended			83 Months Ended
Fixed Assets - Additional Information (Detail) (USD $)	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2011	Mar. 31, 2014
Property Plant And Equipment [Abstract]	'	'	'	'	'	'
Depreciation and amortization expense	$78,000	$15,000	$380,000	$188,000	$63,000	$794,000

Accrued_Expenses_Summary_of_Ac

Accrued Expenses - Summary of Accrued Expenses (Detail) (USD $)	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
Payables And Accruals [Abstract]	'	'	'
Accrued compensation	$505	$386	$720
Deferred rent	345	270	188
Accrued legal and professional fees	283	53	'
Other accrued expenses	34	71	73
Total other income (expense)	$1,167	$780	$981

Derivative_Liability_Additiona

Derivative Liability - Additional Information (Detail) (USD $)	2 Months Ended	3 Months Ended		12 Months Ended
In Millions, except Share data, unless otherwise specified	Nov. 30, 2011	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2011
Derivative [Line Items]	'	'	'	'	'	'
Number of offerings under private placement reverse merger	'	'	'	'	3	'
Warrants maturity term	'5 years	'	'	'	'5 years	'
Warrants [Member]	'	'	'	'	'	'
Derivative [Line Items]	'	'	'	'	'	'
Warrants issued	1,500,000	'	'	'	21,347,182	'
Fair value of the warrant liabilities	'	'	'	'	$32.70	$1.30
Estimated fair value of the outstanding warrant liabilities	'	6.9	'	0.4	20.6	1.3
Change in fair value of the derivative liabilities increase and (decrease)	'	$12	$13.50	$5.10	$9.90	($0.10)
Exercised derivative liabilities	'	6,990,556	'	1,920,874	13,010,237	'
Reclassification of warrant	'	601,735	'	269,657	'	'

Derivative_Liability_Assumptio

Derivative Liability - Assumptions Used to Value Derivative Liabilities at Closing Dates of Private Placements (Detail) (Warrant Derivative Liability [Member], USD $)	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
Warrant Derivative Liability [Member]	'	'	'
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]	'	'	'
Closing price per share of common stock	$7.64	$3.68	$2.60
Exercise price per share	$1	$1	$1
Expected volatility	76.50%	88.80%	92.90%
Risk-free interest rate	0.90%	0.57%	0.54%
Dividend yield	'	'	'
Remaining expected term of underlying securities (years)	'2 years 11 months 16 days	'3 years 10 months 17 days	'4 years 1 month 28 days

Convertible_Notes_Payable_Addi

Convertible Notes Payable - Additional Information (Detail) (USD $)

1 Months Ended

2 Months Ended

3 Months Ended

12 Months Ended

47 Months Ended

83 Months Ended

1 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

2 Months Ended

1 Months Ended

12 Months Ended

Feb. 29, 2012

Oct. 31, 2011

Nov. 30, 2011

Aug. 31, 2011

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2014

Oct. 31, 2011

Dec. 31, 2011

Oct. 31, 2011

Sep. 18, 2011

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2012

Nov. 30, 2011

Sep. 18, 2011

Feb. 29, 2012

Dec. 31, 2011

Mar. 31, 2014

Dec. 31, 2011

Oct. 31, 2011

Dec. 31, 2011

Dec. 31, 2012

Mar. 31, 2014

Dec. 31, 2011

Oct. 31, 2011

Dec. 31, 2011

Investment

Private_placement

Common Stock [Member]

Warrants [Member]

Private Placement [Member]

Convertible Notes Payable [Member]

Local Bridge [Member]

Minimum [Member]

Maximum [Member]

Common Stock [Member]

Unsecured Debt [Member]

Warrants [Member]

Convertible Notes Payable [Member]

Security

Convertible Notes Payable [Member]

Debt Instrument [Line Items]

Convertible notes, interest rate

20.00%

6.00%

10.00%

8.00%

10.00%

Funds raised through loans consisting of Convertible notes

$740,000

$2,543,000

$2,390,000

$4,630,000

Debt instrument maturity year range start

'2011

Debt instrument maturity year range end

'2018

Percentage of per share fair market value of total consideration

75.00%

Warrant Discount

583,700

Expected volatility

110.13%

109.84%

Dividend yield

0.00%

Interest rate

1.11%

1.12%

Convertible Notes principal balance

3,030,000

Accrued interest converted

459,800

Accrued interest converted price range

$0.27

$0.75

Common stock issued for conversion

7,676,828

Purchase shares of common stock for issued warrants

21,347,182

2,909,750

1,309,750

610,155

Warrants expiration period

'5 years

Warrants exercisable price, per share

0.85

7.36

Warrants classified as equity instruments

527,600

Unsecured Convertible Note, outstanding

100,000

Convertible note and accrued interest repaid

110,000

Private placement offering, number of units of securities

16,000,000

Private placement offering, price per unit

$50,000

Private placement offering, aggregate purchase price

1,500,000

Each unit consisted of a convertible note in the principal amount

50,000

Each unit consisted of a convertible note in the principal shares

50,000

Period of warrants

'5 years

Convertible Notes issued

1,500,000

Expiration of warrant

'5 years

Five-year warrants to purchase shares

1,500,000

Notes converted

1,525,387

Debt discount

1,260,300

Issuance of notes, recorded discount for beneficial conversion feature

239,000

239,700

Amortization of debt discount

896,000

1,188,000

2,084,000

Interest expense for amortization of debt discount till date

1,500,000

Payment to Private placement agent

195,000

Exercise price of warrants, per share

Private placement offering, number of units of securities issued

8,000,000

Private placement securities per unit price

Number of common shares included in each unit

Number of warrants included in each unit

Closings under the private placement

Proceeds under Private Placement, total gross

13,722,600

Proceeds under Private Placement, total net

11,593,066

Shares of Common Stock and warrants issued

13,722,600

Purchase of share of its Common Stock

15,247,987

Share issued for warrant

1,525,387

Total cash commissions paid to placement agent and selected dealers

1,372,260

Expense allowance paid to placement agent

411,678

Issued warrants to placement agent for purchase of common stock

6,099,195

Derivative liabilities estimated at fair value

32,742,000

Derivative liabilities exceeded the proceeds, amount

19,019,400

Interest expense

$13,000

$65,000

$1,088,000

$13,000

$1,088,000

$2,067,000

$3,484,000

Registration Rights Agreement term

'90 days

Monetary penalties charge on failure of Effectiveness Deadline

0.50%

Penalty period

'30 days

Stockholders_Equity_Additional

Stockholders' Equity - Additional Information (Detail) (USD $)

0 Months Ended

1 Months Ended

2 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

1 Months Ended

0 Months Ended

3 Months Ended

12 Months Ended

48 Months Ended

83 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

48 Months Ended

12 Months Ended

Aug. 02, 2013

Aug. 31, 2013

Oct. 31, 2011

Mar. 31, 2012

Mar. 31, 2013

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2010

Dec. 31, 2009

Dec. 31, 2008

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Feb. 29, 2008

Mar. 31, 2014

Nov. 30, 2013

Feb. 29, 2008

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Dec. 31, 2012

Mar. 31, 2013

Mar. 31, 2014

Dec. 31, 2012

Mar. 31, 2013

Mar. 31, 2014

Dec. 31, 2012

31-May-08

Dec. 31, 2011

Aug. 02, 2013

Jul. 17, 2013

Aug. 02, 2013

Mar. 31, 2014

Aug. 31, 2013

Jan. 31, 2012

Research and development expense [Member]

General and administrative expense [Member]

CEO and three directors [Member]

Equity Distribution Agreement [Member]

Restricted stock [Member]

Restricted stock units (RSUs) [Member]

Performance Based Restricted Stock Units (RSUs) [Member]

Equity Incentive Plan 2008 [Member]

Other Plan [Member]

Underwriting Agreement [Member]

Equity Incentive Plan 2012 [Member]

Maximum [Member]

Consultants [Member]

Senior Management [Member]

Non Executive Employees [Member]

Senior Management [Member]

Restricted stock [Member]

Overallotment Option Exercised [Member]

Class of Stock [Line Items]

Common stock issued for conversion

7,676,828

Convertible Notes principal balance

$3,030,000

Accrued interest converted

459,800

Issuance of common stock related to Merger

21,247,987

Warrants exercised

7,090,556

3,201,633

13,532,487

Issuance of common stock from warrant exercises, net, Shares

6,131,198

2,713,207

13,423,622

Issuances of common stock from stock option exercise, Shares

183,796

224,064

Shares authorized under shelf registration statement

150,000,000

100,000,000

Issuance of common stock

64,686,919

78,113,639

58,535,411

10,350,000

1,350,000

Offering price per share

$4.50

$4.23

Proceeds from issuance of common stock

43,400,000

Underwriting discounts and commissions and other offering expenses

3,200,000

Number of shares to be offered and sold in equity distribution agreement

4,000,000

Shares sold under equity distribution agreement

10,350,000

334,412

Value of shares sold under equity distribution agreement

3,500,000

Common stock restricted issued number of founder

Restricted common stock to founders

11,779,960

1,258,934

1,086,662

172,272

Restricted stock vesting conditions

'25% vesting after the first year and the remaining 75% vesting in equal quarterly portions over the following three years

Portion of restricted common stock vesting after one year

25.00%

Portion of restricted common stock vesting over three years

75.00%

Stock option granted, quarterly vesting restricted term

'3 years

Common shares authorized to be issued

1,521,584

5,000,000

6,553,986

Shares issued during the year

Termination date of Equity Incentive Plan

1-Jul-18

Shares available for issuance

11,553,986

Termination period of Equity Incentive Plan

'10 years

Restricted stock awards granted

55,000

60,000

1,380,000

61,406

219,369

130,422

12,627,697

55,000

60,000

100,000

950,000

130,000

200,000

Percentage of vesting schedule

25.00%

100.00%

Period for vesting schedule over start date

'4 years

'6 months

Restricted stock surrendered

10,000

95,842

24,690

89,674

218,655

Common stock returned by holders

10,000

95,842

Restricted stock awards vested during the period

221,302

472,247

1,233,409

3,233,193

3,256,191

5,373,004

65,211

50,000

405,000

211,250

Stock option granted with immediate vesting

24,690

218,655

89,674

Total employee stock-based compensation recorded as operating expenses

4,000

16,000

23,000

474,000

801,000

812,000

3,000

478,000

817,000

835,000

3,000

2,141,000

Unrecognized restricted stock-based compensation expense

$747,000

Total unrecognized compensation cost related, weighted average period

'1 year 5 months 16 days

Stockholders_Equity_Summary_of

Stockholders' Equity - Summary of Company's Restricted Stock Award Activity (Detail)	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'	'	'	'	'	'	'
Beginning balance, Unvested, Number of Shares	1,162,044	985,742	1,111,295	4,283,082	7,319,904	12,562,486	'
Granted, Number of Shares	55,000	60,000	1,380,000	61,406	219,369	130,422	12,627,697
Vested, Number of Shares	-221,302	-472,247	-1,233,409	-3,233,193	-3,256,191	-5,373,004	-65,211
Canceled / forfeited, Number of Shares	-10,000	'	-95,842	'	'	'	'
Ending balance, Unvested, Number of Shares	985,742	573,495	1,162,044	1,111,295	4,283,082	7,319,904	12,562,486

Stockholders_Equity_Additional1

Stockholders' Equity - Additional Information 1 (Detail) (USD $)

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

83 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

Mar. 31, 2013

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2014

Oct. 12, 2011

Mar. 31, 2013

Mar. 31, 2014

Dec. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Dec. 31, 2012

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Oct. 12, 2011

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Dec. 31, 2012

Mar. 31, 2013

Mar. 31, 2014

Dec. 31, 2012

Research and development expense [Member]

General and administrative expense [Member]

2008 Plan [Member]

2012 Plan [Member]

Stock options [Member]

Restricted stock units (RSUs) [Member]

One Year Vesting [Member]

Research and development expense [Member]

General and administrative expense [Member]

2008 Plan [Member]

2012 Plan [Member]

Class of Stock [Line Items]

Equity Incentive Plan, shares

927,981

2,519,572

2,023,394

896,256

Granted incentive stock options to purchase shares of Common stock, exercise price

$0.08

Restricted stock vesting conditions

'A quarter of which vested on the one year anniversary of employment, in May 2012, and the remaining options are vesting ratably over the remaining 36 month term.

'A quarter of which will vest on either the one year anniversary of employment or one year anniversary of the vesting commencement date.

Remaining options vest

'36 months

Issuances of common stock from stock option exercises, Shares

183,796

224,064

927,981

2,519,572

2,023,394

Stock option granted with immediate vesting

24,690

218,655

89,674

24,690

218,655

83,986

Stock option granted, restricted portion

99,500

126,000

122,500

70,750

Stock option granted, quarterly vesting restricted term

'3 years

Weighted-average remaining contractual term of options exercisable

'8 years 6 months

Weighted-average remaining contractual term of options outstanding

'8 years 11 months 1 day

Total employee stock-based compensation recorded as operating expenses

$4,000

$16,000

$23,000

$474,000

$801,000

$812,000

$3,000

$370,000

$4,000

$3,783,000

$600,000

$6,000

$4,761,000

$58,000

$462,000

$81,000

$312,000

$4,000

$3,321,000

$519,000

$6,000

Total unrecognized compensation cost related to unvested stock option grants

$16,045,500

Total unrecognized compensation cost related, weighted average period

'3 years 6 months

Stockholders_Equity_Summary_of1

Stockholders' Equity - Summary of Stock Option Activity (Detail) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2011
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'	'	'	'
Options Outstanding, Beginning balance	2,690,586	3,618,567	896,256	'
Options Exercised, Aggregate Intrinsic Value	'	$1,002,419	$564,641	'
Granted, Options Outstanding	927,981	2,519,572	2,023,394	896,256
Canceled, Options Outstanding	'	-18,455	-5,000	'
Exercised, Options Outstanding	'	-183,796	-224,064	'
Options Outstanding, Ending balance	3,618,567	5,935,888	2,690,586	896,256
Weighted-Average Exercise Price, Options Beginning balance	$1.48	$2.11	$0.08	'
Vested and Exercisable, Options Outstanding	'	1,546,377	'	'
Options granted, Weighted-Average Exercise Price	$3.93	$8.63	$1.95	$0.08
Options canceled, Weighted-Average Exercise Price	'	$3.31	$2.25	'
Options exercised, Weighted-Average Exercise Price	'	$2.19	$0.08	'
Weighted-Average Exercise Price, Options Ending balance	$2.11	$4.87	$1.48	$0.08
Aggregate Intrinsic Value, Options Beginning balance	3,041,476	5,909,154	'	'
Vested and Exercisable, Weighted-Average Exercise Price	'	$2.73	'	'
Aggregate Intrinsic Value, Options Ending balance	5,909,154	20,482,823	3,041,476	'
Vested and Exercisable at March 31, 2014	'	$7,733,041	'	'

Stockholders_Equity_Fair_Value

Stockholders' Equity - Fair Value of Employee Stock Options (Detail) (USD $)	1 Months Ended	3 Months Ended	12 Months Ended
	Nov. 30, 2013	Mar. 31, 2013	Mar. 31, 2014	Dec. 31, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'	'	'	'
Dividend yield	'	'	'	'
Volatility	96.90%	96.83%	78.22%	96.22%
Risk-free interest rate	0.60%	1.19%	1.32%	0.89%
Expected life of options	'	'6 years 26 days	'6 years	'6 years 18 days
Weighted average grant date fair value	'	$3.04	$5.92	$1.50

Stockholders_Equity_Additional2

Stockholders' Equity - Additional Information 2 (Detail) (USD $)

1 Months Ended

3 Months Ended

12 Months Ended

83 Months Ended

12 Months Ended

1 Months Ended

3 Months Ended

12 Months Ended

0 Months Ended

3 Months Ended

12 Months Ended

Nov. 30, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2014

Oct. 31, 2011

Dec. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Mar. 31, 2014

Nov. 30, 2013

Mar. 31, 2013

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2012

Mar. 31, 2014

Dec. 21, 2012

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Agreement

Minimum [Member]

Maximum [Member]

Warrants [Member]

Tender offer [Member]

Amendment April 2013 [Member]

Amendment March 2013 [Member]

Minimum [Member]

Maximum [Member]

Consultants [Member]

Warrants [Member]

Minimum [Member]

Maximum [Member]

Class of Stock [Line Items]

Purchase shares of common stock for issued warrants

21,347,182

2,909,750

Number of warrants exercised

3,852,214

225,000

13,259,987

348,630

Proceeds from warrant exercise

$3,850,000

$210,000

$11,356,000

$891,000

Number of warrant exercised through cashless

100,000

3,138,342

2,628,003

272,500

Cashless exercise for issuance of common stock

58,220

2,220,764

2,139,577

163,635

Outstanding warrants to purchase

14,500,000

Warrants exercisable price, per share

0.85

7.36

1.7

3.24

0.85

0.9

Exercise price of warrant Amended

$0.80

Warrant proceeds

9,600,000

Gross proceeds of warrants tendered

32,743,000

7,700,000

Recognized expenses of warrants

1,900,000

Costs incurred related to warrant exercises

400,000

Number of warrants exercised during period recorded as derivative liability

6,990,556

1,920,874

13,010,237

Warrants to purchase common stock

75,000

650,000

269,657

601,735

Interest expense

13,000

65,000

1,088,000

13,000

1,088,000

2,067,000

3,484,000

65,000

12,000

Number of agreement with consultants

Life of warrants

'5 years

'2 years

'5 years

Estimated fair value of warrants

404,000

890,000

Volatility

96.90%

96.83%

78.22%

96.22%

79.80%

103.80%

Risk-free interest rate

0.60%

1.19%

1.32%

0.89%

0.24%

0.63%

Recognized expenses of warrants

$261,000

$72,000

$556,000

$163,000

Warrants earned, service period

'12 months

Weighted-average remaining contractual term of options exercisable

'8 years 6 months

'2 years 6 months 18 days

Preferred stock, shares authorized

25,000,000

Preferred stock, shares outstanding

Stockholders_Equity_Summary_of2

Stockholders' Equity - Summary of Warrant Activity (Detail) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Options Outstanding, Beginning balance	2,690,586	3,618,567	896,256	'
Granted, Options Outstanding	927,981	2,519,572	2,023,394	896,256
Expired / Canceled Options Outstanding	'	18,455	5,000	'
Exercised, Options Outstanding	'	-183,796	-224,064	'
Options Outstanding, Ending balance	3,618,567	5,935,888	2,690,586	896,256
Weighted-Average Exercise Price, Options Beginning balance	$1.48	$2.11	$0.08	'
Granted, Weighted-Average Exercise Price	$3.93	$8.63	$1.95	$0.08
Expired / Canceled Weighted-Average Exercise Price	'	$3.31	$2.25	'
Exercised, Weighted-Average Exercise Price	'	$2.19	$0.08	'
Weighted-Average Exercise Price, Options Ending balance	$2.11	$4.87	$1.48	$0.08
Warrants [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Options Outstanding, Beginning balance	11,374,445	4,283,889	2,909,750	'
Granted, Options Outstanding	'	112,500	21,997,182	2,909,750
Expired / Canceled Options Outstanding	'	'	'	'
Exercised, Options Outstanding	-7,090,556	-3,201,633	-13,532,487	'
Options Outstanding, Ending balance	4,283,889	1,194,756	11,374,445	2,909,750
Weighted-Average Exercise Price, Options Beginning balance	$1.08	$1.17	$1	'
Granted, Weighted-Average Exercise Price	'	$7.36	$1.04	$1
Expired / Canceled Weighted-Average Exercise Price	'	'	'	'
Exercised, Weighted-Average Exercise Price	$1.01	$1.16	$0.84	'
Weighted-Average Exercise Price, Options Ending balance	$1.17	$1.79	$1.08	$1

Stockholders_Equity_Common_Sto

Stockholders' Equity - Common Stock Reserved for Future Issuance (Detail)	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Common stock reserved for future issuance	11,401,937
Warrants [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Common stock reserved for future issuance	1,194,756
Stock options [Member] \| Equity Incentive Plan 2008 [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Common stock reserved for future issuance	672,192
Stock options [Member] \| Equity Incentive Plan 2012 [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Common stock reserved for future issuance	9,534,989

Commitments_and_Contingencies_1

Commitments and Contingencies - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended		12 Months Ended			83 Months Ended
	Dec. 05, 2013	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2011	Mar. 31, 2014
	sqft	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2011	Mar. 31, 2014
Commitments And Contingencies Disclosure [Abstract]	'	'	'	'	'	'	'
Rent expense	'	$105,500	$60,200	$561,500	$325,600	$145,200	$1,317,200
Base rent under the lease	38,800	'	'	38,800	'	'	'
Base rent escalators	3.00%	'	'	3.00%	'	'	3.00%
Lease term with option to extend	'	'	'	'48 months	'	'	'
Lease expiration date	1-Aug-16	'	'	'	'	'	'
Rent expense per month	38,934	'	'	'	'	'	'
Area of leased office space	15,539	'	'	'	'	'	'
Additional office space	14,500	'	'	'	'	'	'
Increased office space size	15,268	'	'	'	'	'	'
Total office space under lease agreement	30,807	'	'	'	'	'	'
Expansion premises commencement date	1-Sep-14	'	'	'	'	'	'
Depreciation expense	'	$1,700	'	$6,800	$2,900	'	'

Commitments_and_Contingencies_2

Commitments and Contingencies - Future Minimum Rental Payments Required under Operating Leases that have Initial or Remaining Non-Cancellable Lease Terms in Excess of One Year (Detail) (USD $)	Mar. 31, 2014
In Thousands, unless otherwise specified	Mar. 31, 2014
Commitments And Contingencies Disclosure [Abstract]	'
Fiscal year ended March 31, 2015	$766
Fiscal year ended March 31, 2016	981
Fiscal year ended March 31, 2017	986
Fiscal year ended March 31, 2018	1,004
Fiscal year ended March 31, 2019	1,034
Thereafter	2,439
Total	$7,210

Commitments_and_Contingencies_3

Commitments and Contingencies - Agreement to Lease Certain Laboratory Equipment under Non-Cancellable Capital Lease, Which is Included in Fixed Assets (Detail) (Equipment [Member], USD $)	Mar. 31, 2014
In Thousands, unless otherwise specified	Mar. 31, 2014
Equipment [Member]	'
Property, Plant and Equipment [Line Items]	'
Lab equipment	$34
Less accumulated depreciation	-11
Net book value	$23

Commitments_and_Contingencies_4

Commitments and Contingencies - Future Minimum Capital Lease Payments (Detail) (USD $)	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
Contractual Obligation Fiscal Year Maturity Schedule [Abstract]	'	'	'
Fiscal year ended March 31, 2015	$11	'	'
Fiscal year ended March 31, 2016	4	'	'
Total minimum lease payments	15	'	'
Amount representing interest	'	'	'
Present value of minimum lease payments	15	'	'
Less current portion	-10	-10	-10
Long term portion	$5	$15	$17

Licensing_Agreements_and_Resea2

Licensing Agreements and Research Contracts - Additional Information (Detail) (USD $)

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2014

Mar. 12, 2010

Mar. 24, 2009

Mar. 31, 2014

Mar. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Mar. 31, 2014

2-May-11

Feb. 28, 2013

Licensing Agreements [Member]

University of Missouri [Member]

Clemson University [Member]

Becton Dickinson [Member]

Licensing Agreements [Member]

Minimum [Member]

Maximum [Member]

Other Assets [Member]

Finite-Lived Intangible Assets [Line Items]

License cost

$5,000

$25,000

$32,500

Royalty fees percentage minimum

1.00%

1.50%

Royalty fees percentage maximum

3.00%

Annual royalty

5,000

25,000

20,000

40,000

Other assets amortized

97,000

89,000

80,000

89,000

5,000

25,000

65,000

Expected expiration year of license agreement

'2029

Prior patent costs relating to the license agreements

193,500

23,800

Additional royalty

12,500

Royalty payment

Additional license fee to reimburse future patent costs

32,500

Expected expiration year of license agreement

'2024-05

Initial royalty payment due

4,000

Annual royalty payment due

30,000

20,000

Payments to purchase exclusive rights to intellectual property

18,500

Amortization expense of licenses

2,000

1,700

8,500

7,000

5,200

25,200

Weighted average remaining amortization period for all licenses

'11 years

Annual amortization expense of licenses year 1

8,500

Annual amortization expense of licenses year 2

8,500

Annual amortization expense of licenses year 3

8,500

Annual amortization expense of licenses year 4

8,500

Annual amortization expense of licenses year 5

$8,500

Licensing_Agreements_and_Resea3

Licensing Agreements and Research Contracts - Schedule of Capitalized License Fees (Detail) (Licensing Agreements [Member], USD $)	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
Licensing Agreements [Member]	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'
License fees	$114,000	$114,000	$95,000
Less accumulated amortization	-25,000	-17,000	-15,000
License fees, net	$89,000	$97,000	$80,000

Income_Taxes_Summary_of_Net_De

Income Taxes - Summary of Net Deferred Tax Assets (Detail) (USD $)	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
Deferred tax assets:	'	'	'
Net operating loss carry forwards	'	'	'
Research and development credits	'	'	'
Depreciation and amortization	22	-1	-2
Accrued expenses and reserves	280	224	290
Stock compensation	1,941	743	562
Other, net	1	1	'
Total deferred tax assets	2,244	967	850
Valuation allowance	-2,244	-967	-850
Deferred tax assets net	'	'	'

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014
Operating Loss Carryforwards [Line Items]	'	'	'
Increase (decrease) in valuation allowance	'	$117,000	$1,277,000
Federal net operating loss carryforwards	34,838,000	'	34,838,000
State net operating loss carryforwards	34,833,000	'	34,833,000
Federal and state net operating loss carryforwards expiring year	'	'	'2028
Net operating loss carryforwards related to windfall tax benefits	3,389,000	'	3,389,000
Federal research tax credit carryforwards expiration period	'2028	'	'
Accruals for income tax accounting uncertainties	0	'	0
Accrued expense regarding interest or penalties	0	'	0
Federal [Member]	'	'	'
Operating Loss Carryforwards [Line Items]	'	'	'
Research tax credit carryforwards	450,000	'	450,000
State [Member]	'	'	'
Operating Loss Carryforwards [Line Items]	'	'	'
Research tax credit carryforwards	$548,000	'	$548,000