Document and Entity Information	6 Months Ended
Document and Entity Information	Sep. 30, 2013	Nov. 01, 2013
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2013
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	Q2
Trading Symbol	ONVO
Entity Registrant Name	ORGANOVO HOLDINGS, INC.
Entity Central Index Key	0001497253
Current Fiscal Year End Date	--03-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		77,278,303

Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Current Assets
Cash and cash equivalents	$ 53,357	$ 15,628
Grant receivable		101
Inventory	74	88
Prepaid expenses and other current assets	304	327
Total current assets	53,735	16,144
Fixed Assets - Net	1,031	1,045
Restricted Cash	38	88
Other Assets - Net	94	98
Total assets	54,898	17,375
Current Liabilities
Accounts payable	477	641
Accrued expenses	1,583	780
Deferred revenue	75	53
Capital lease obligation, current portion	10	10
Warrant liabilities	795	6,898
Total current liabilities	2,940	8,382
Deferred revenue, net of current portion	6	9
Capital lease obligation, net of current portion	10	15
Total liabilities	2,956	8,406
Commitments and Contingencies (Note 5)
Stockholders' Equity
Common stock, $0.001 par value; 150,000,000 shares authorized, 76,818,625 and 64,686,919 shares issued and outstanding at September 30, 2013 and March 31, 2013, respectively	77	65
Additional paid-in capital	132,387	75,269
Deficit accumulated during the development stage	(80,522)	(66,365)
Total stockholders' equity	51,942	8,969
Total Liabilities and Stockholders' Equity	$ 54,898	$ 17,375

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2013	Mar. 31, 2013
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	76,818,625	64,686,919
Common stock, shares outstanding	76,818,625	64,686,919

Condensed Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended		77 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013
Revenues
Product					$ 224
Collaborations	23	374	117	633	2,013
Grants		95	12	95	955
Total Revenues	23	469	129	728	3,192
Cost of product revenue					134
Selling, general, and administrative expenses	4,026	2,981	6,404	4,037	18,943
Research and development expenses	1,599	1,106	3,061	1,759	11,143
Loss from Operations	(5,602)	(3,618)	(9,336)	(5,068)	(27,028)
Other Income (Expense)
Fair value of warrant liabilities in excess of proceeds received					(19,019)
Change in fair value of warrant liabilities	(4,787)	42,252	(4,811)	8,315	(26,782)
Financing transaction costs in excess of proceeds received					(2,130)
Loss on inducement to exercise warrants					(1,904)
Loss on disposal of fixed assets		(158)	(4)	(158)	(162)
Interest expense			(13)		(3,484)
Interest income	3	1	7	3	17
Other income (expense)		1		1	(30)
Total Other Income (Expense)	(4,784)	42,096	(4,821)	8,161	(53,494)
Net Income (Loss)	$ (10,386)	$ 38,478	$ (14,157)	$ 3,093	$ (80,522)
Net income (loss) per common share - basic	$ (0.14)	$ 0.87	$ (0.21)	$ 0.07
Net income (loss) per common share - diluted	$ (0.14)	$ 0.69	$ (0.21)	$ 0.05
Weighted average shares used in computing net income (loss) per common share - basic	72,716,031	44,099,554	68,776,718	43,614,514
Weighted average shares used in computing net income (loss) per common share - diluted	72,716,031	55,849,360	68,776,718	59,359,415

Condensed 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
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 the merger	13,723,000	14,000	13,709,000
Issuance of Common stock through private placements in connection with the 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		13,424,000
Issuance of restricted Common stock		1,000	(1,000)
Issuance of restricted Common stock, Shares		1,380,000
Restricted stock forfeitures and adjustments		(186,000)
Warrant liability removed due to exercises of warrants	23,321,000		23,321,000
Issuances of Common stock from stock option exercises	18,000		18,000
Issuances of Common stock from stock option exercises, Shares	224,064	224,000
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		6,131,000
Issuance of restricted Common stock, Shares		55,000
Restricted stock forfeitures and adjustments		(34,000)
Warrant liability removed due to exercises of warrants	23,869,000		23,869,000
Issuances of Common stock from stock option exercises, Shares
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 Common stock through conversion of notes payable, Shares	1,870,986
Issuance of warrants to consultants/Warrants issued with convertible notes and conversion of notes	767,000
Issuance of Common stock from warrant exercises, net	651,000	2,000	649,000
Issuance of Common stock from warrant exercises, net, Shares		1,871,000
Issuance of restricted Common stock
Issuance of restricted Common stock, Shares		60,000
Restricted stock forfeitures and adjustments, value
Restricted stock forfeitures and adjustments		(157,000)
Warrant liability removed due to exercises of warrants	10,147,000		10,147,000
Issuances of Common stock from stock option exercises	20,000		20,000
Issuances of Common stock from stock option exercises, Shares	7,300	8,000
Issuance of Common stock through public offering	43,445,000	10,000	43,435,000
Issuance of Common stock through public offering, Shares		10,350,000
Stock-based compensation expense	2,088,000		2,088,000
Expense related to modification of warrants	12,000		12,000
Warrant liability reclassified to equity	767,000		767,000
Net Loss	(14,157,000)			(14,157,000)
Ending balance at Sep. 30, 2013	$ 51,942,000	$ 77,000	$ 132,387,000	$ (80,522,000)
Ending balance, Shares at Sep. 30, 2013		76,819,000

Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended		77 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013
Cash Flows From Operating Activities
Net income (loss)	$ (14,157)	$ 3,093	$ (80,522)
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Amortization of deferred financing costs			438
Amortization of warrants issued for services	72	36	890
Depreciation and amortization	190	100	621
Loss on disposal of fixed assets	4	158	162
Amortization of debt discount			2,084
Interest accrued on convertible notes payable			495
Fair value of warrant liabilities in excess of proceeds			19,019
Change in fair value of warrant liabilities	4,811	(8,315)	26,782
Loss on inducement to exercise warrants			1,904
Expense associated with warrant modification	12		77
Stock-based compensation	2,088	1,281	4,388
Warrants issued in connection with exchange agreement			528
Increase (decrease) in cash resulting from changes in:
Grants receivable	101	(96)
Inventory	14	(283)	(737)
Prepaid expenses and other assets	(49)	12	(304)
Accounts payable	(164)	(380)	477
Accrued expenses	803	429	1,583
Deferred revenue	19	(194)	81
Net cash used in operating activities	(6,256)	(4,159)	(22,034)
Cash Flows From Investing Activities
Deposits released from restriction (restricted cash deposits)	50	(50)	(38)
Purchases of fixed assets	(176)	(250)	(1,097)
Purchases of intangible assets			(114)
Net cash used in investing activities	(126)	(300)	(1,249)
Cash Flows From Financing Activities
Proceeds from issuance of convertible notes payable			4,630
Proceeds from issuance of common stock and warrants, net	44,096	1,768	72,534
Proceeds from exercise of stock options	20	18	38
Proceeds from issuance of related party notes payable			250
Repayment of related party notes payable			(250)
Principal payments on capital lease obligation	(5)	(4)	(14)
Repayment of convertible notes and interest payable			(110)
Deferred financing costs			(438)
Net cash provided by financing activities	44,111	1,782	76,640
Net Increase (Decrease) in Cash and Cash Equivalents	37,729	(2,677)	53,357
Cash and Cash Equivalents at Beginning of Period	15,628
Cash and Cash Equivalents at End of Period	53,357	7,676	53,357
Supplemental Disclosure of Cash Flow Information:
Interest			10
Income Taxes			$ 3

Condensed Consolidated Statements of Cash Flows (Parenthetical) (USD $)	6 Months Ended	77 Months Ended
	Sep. 30, 2013	Sep. 30, 2013
Statement Of Cash Flows [Abstract]
Warrant liability reduced	$ 10,147,000	$ 57,337,000
Warrant reclassified as equity instruments	767,000	2,653,000
Warrants and related beneficial conversion feature valued		824,000
Warrant issued in connection with convertible notes payable		1,260,000
Issuance of common stock to note holders		9,202,215
Convertible notes principal balance		4,530,000
Accrued interest		485,000
Issued warrants with connection with reverse merger and private placement		32,743,000
Purchased equipment through capital lease		34,000
Issued warrants to purchase share of common stock for consulting services shares		650,000
Issued warrants to purchase shares of common stock for consulting services		$ 890,000

Description of Business and Summary of Significant Accounting Policies

6 Months Ended

Sep. 30, 2013

Accounting Policies [Abstract]

Description of Business and Summary of Significant Accounting Policies

2. Description of Business and Summary of Significant Accounting Policies

Nature of operations and basis of presentation

References in these notes to the unaudited condensed 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 September 30, 2013, the Company has devoted substantially all of its efforts to product development, 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.

The accompanying interim condensed consolidated financial statements have been prepared by the Company, without audit, in accordance with the instructions to Form 10-Q and, therefore, do not necessarily include all information and footnotes necessary for a fair statement of its financial position, results of operations, stockholders’ equity (deficit) and cash flows in accordance with generally accepted accounting principles (“GAAP”). The balance sheet at March 31, 2013 is derived from the audited balance sheet at that date.

In the opinion of management, the unaudited financial information for the interim periods presented reflects all adjustments, which are only normal and recurring, necessary for a fair statement of the Company’s financial position, results of operations, stockholders’ equity (deficit) and cash flows. These financial statements should be read in conjunction with the financial statements included in the Company’s Transition Report filed on Form 10-KT for the transition period ended March 31, 2013 filed with the Securities and Exchange Commission (the “SEC”) on May 24, 2013. Operating results for interim periods are not necessarily indicative of operating results for the Company’s fiscal year ending March 31, 2014.

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, 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 will continue 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 consist 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 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, Organovo Holdings’ Board of Directors and stockholders adopted the 2012 Equity Incentive Plan (the “2012 Plan”). In addition, Organovo Holdings 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. The Company continues to trade under the symbol “ONVO” but withdrew its shares from quotation on the OTC QX concurrent with listing its shares on the NYSE:MKT.

Liquidity

As of September 30, 2013, the Company had an accumulated deficit of approximately $80.5 million. The Company also had negative cash flows from operations of approximately $6.3 million during the six months ended September 30, 2013.

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 4).

Through September 30, 2013, 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 cannot predict with certainty when, if ever, it will require additional capital to further fund the 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, and from revenue derived from grants and collaborative research agreements. However, the Company cannot provide assurance that it will not require additional funding in the future. In addition, the Company cannot be sure that additional financing will be available if and when needed, or that, if available, financing will be obtained on terms favorable to the Company and its stockholders. Having insufficient funds may require the Company to delay, scale back, or eliminate some or all of its development programs or relinquish rights to its technology on less favorable terms than it would otherwise choose. Failure to obtain adequate financing could eventually adversely affect the Company’s ability to operate as a going concern.

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 condensed consolidated financial statements include those assumed in computing the valuation of warrants, 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 September 30, 2013 and March 31, 2013, the Company had approximately $38,300 and $88,300, respectively, of restricted cash deposited with a financial institution. $38,300 is held in certificates of deposit to support a letter of credit agreement related to the facility lease entered into during 2012. The additional $50,000 included in the March 31, 2013 balance represents funds held by the financial institution as a guarantee for the Company’s commercial credit cards. These funds were released from restriction during the six months ended September 30, 2013 as a result of the Company transferring its credit card program to a different financial institution.

Grant receivable

Grant receivable represents the amount due from the National Institutes of Health (“NIH”) under a research grant. The Company considers the grant 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 at September 30, 2013 and March 31, 2013 consisted of approximately $74,000 and 88,000 in raw materials, respectively.

The Company provides inventory allowances based on excess or obsolete inventories determined based on anticipated use in the final product. There was no obsolete inventory reserve as of September 30, 2013 or March 31, 2013.

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 September 30, 2013.

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 3). 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 the Company uses 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, the Company expects 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 September 30 and March 31, 2013 (in thousands):
	Balance at September 30, 2013		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	795		—		—	$	795


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

The following table presents the activity for liabilities measured at estimated fair value using unobservable inputs for 2012 through September 30, 2013:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)


	Warrant Derivative Liability ($000’s)
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		4,811
Warrant liability removal due to settlements		(10,147	)
Warrant liability reclassified to equity		(767	)

Balance at September 30, 2013	$	795

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, NIH and U.S. Treasury Department Grants, 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 September 30, 2013 and March 31, 2013, the Company had approximately $81,000 and $62,000, 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 the 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 the 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, total revenue recognized on the contract from inception through September 30, 2013 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 expected to occur 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. This amendment extended the original contract (which runs concurrently) from twenty-one months to twenty-eight months. The Company recorded approximately $22,000, and $299,000 related to the research contract in recognition of the proportional performance achieved, for the three months ended September 30, 2013 and 2012, respectively and $115,000 and $558,000 for the six months ended September 30, 2013 and 2012, respectively. Total revenue recognized on the contract from inception through September 30, 2013 was approximately $1,335,500.

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 vendor-specific objective evidence (“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 cover 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 September 30, 2013.

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 was approximately $0 and $95,000, for the three months ended September 30, 2013 and 2012, respectively, and $12,000 and $95,000 for the six months ended September 30, 2013 and 2012, respectively. Total revenue recorded under these grants from inception through September 30, 2013 was approximately $558,000.

Stock-based compensation

The Company accounts for stock-based compensation in accordance with the Financial Accounting and 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 its estimated fair value as it vests.

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 three and six months ended September 30, 2013 and 2012, respectively, and for the period April 19, 2007 (inception) through September 30, 2013, the comprehensive income (loss) was equal to the net income (loss).

Net income (loss) per share

Basic and diluted net income (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 basic income (loss) per share excludes any assumed exercise of stock options and warrants, the assumed release of restriction of restricted stock units, and shares subject to repurchase as the effect would be anti-dilutive. Diluted net income per share includes the impact of potentially dilutive securities. In computing dilutive net income per share, in-the-money common share equivalents are calculated based on the average share price for each period using the treasury stock method. No dilutive effect was calculated for the three or six months ended September 30, 2013, 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 6.9 million for the three and six months ended September 30, 2013. The incremental dilutive common share equivalents were 11.7 million and 15.7 million for the three and six months ended September 30, 2012, respectively.

Derivative Liability

6 Months Ended

Sep. 30, 2013

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Derivative Liability

3. 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 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. 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 revalues the warrants as of the end of each reporting period, and the estimated fair value of the outstanding warrant liabilities was approximately $0.8 million and $6.9 million, as of September 30, 2013 and March 31, 2013, respectively. The changes in fair value of the derivative liabilities for the three months ended September 30, 2013 and 2012 were an increase of approximately $4.8 million and a decrease of approximately $42.3 million, respectively, and are included in other income (expense) in the statement of operations. The changes in fair value of the derivative liabilities for the six months ended September 30, 2013 and 2012 were an increase of approximately $4.8 million and a decrease of approximately $8.3 million, respectively.

During the three months ended September 30, 2013 and 2012, 1,782,928 and 1,668,475 warrants, respectively, that were classified as derivative liabilities were exercised. During the six months ended September 30, 2013 and 2012, 1,817,928 and 1,768,475 warrants, respectively, that were classified as derivative liabilities were exercised. The warrants were revalued as of the settlement dates, and the change in fair value was recognized to earnings. In addition, during the six months ended September 30, 2013, the Company entered into amendment agreements with certain of the warrant holders, which removed the down-round pricing protection provisions, resulting in 269,657 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:


	September 30, 2013			March 31, 2013			September 30, 2012

Closing price per share of common stock	$	5.77		$	3.68		$	2.05
Exercise price per share	$	1.00		$	1.00		$	1.00
Expected volatility		82.6	%		88.8	%		102.7	%
Risk-free interest rate		0.63	%		0.57	%		0.62	%
Dividend yield		—			—			—
Remaining expected term of underlying securities (years)		3.44			3.88			4.42

In addition, as of the valuation dates, management assessed the probabilities of future financing 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.

- Definition

The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.

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+ Details

Stockholders' Equity

6 Months Ended

Sep. 30, 2013

Equity [Abstract]

Stockholders' Equity

4. Stockholders’ Equity

Common stock

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 $3.1 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 addition, during the three months ended September 30, 2013 and 2012, the Company issued 1,670,851 and 1,673,247 shares of common stock upon exercise of 2,026,428 and 1,675,975 warrants, respectively, as a result of certain warrant holders utilizing the cashless exercise provisions of their warrants. During the six months ended September 30, 2013 and 2012, the Company issued 1,870,986 and 1,810,831 shares of common stock upon the exercise of 2,278,557 and 1,820,975 warrants, respectively, as a result of certain warrant holders utilizing the cashless exercise provisions of their warrants.

Restricted stock awards

In May 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 2012 or the six months ended September 30, 2013, 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 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 11,553,996 shares issuable under the 2012 Plan. The 2012 Plan terminates ten years after its adoption.

There were 1,380,000 shares of restricted stock issued during the three and six months ended September 30, 2012, respectively. There were no shares of restricted stock cancelled due to terminations during the three and six months ended September 30, 2012.

During the six months ended September 30, 2013, the Company issued an aggregate of 60,000 restricted stock units with immediate vesting to a consultant.

During the three months ended September 30, 2013, there were 160,540 shares of restricted stock cancelled 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 296,250 restricted stock units. Upon the return of the common stock, 160,540 stock options with immediate vesting were granted to the individuals at the vesting date market value strike price.

A summary of the Company’s restricted stock award activity for 2012 through September 30, 2013 is as follows:


	Number of Shares
Unvested at December 31, 2011		1,111,295
Granted		1,380,000
Vested		(1,143,735	)
Canceled / forfeited		(185,516	)

Unvested at December 31, 2012		1,162,044
Granted		55,000
Vested		(196,612	)
Canceled / forfeited		(34,690	)

Unvested at March 31, 2013		985,742
Granted		60,000
Vested		(356,250	)
Canceled / forfeited		—

Unvested at September 30, 2013		689,492

The fair value of each restricted common stock award is recognized as stock-based compensation 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 $131,000 and $998,000 during the three months ended September 30, 2013 and 2012, respectively and approximately $533,000 and $998,000 for the six months ended September 30, 2013 and 2012, respectively. The Company recorded restricted stock-based compensation expense of approximately $1,854,000 for the period from April 19, 2007 (inception) through September 30, 2013. Expense included approximately $4,000 and $84,000 for research and development during the three months ended September 30, 2013 and 2012, respectively and $8,000 and $84,000 for the six months ended September 30, 2013 and 2012, respectively. General and administrative expense was $127,000 and $914,000 for the three months ended September 30, 2013 and 2012, respectively, and $525,000 and $914,000 for the six months ended September 30, 2013 and 2012, respectively.

As of September 30, 2013, total unrecognized restricted stock-based compensation expense was approximately $1,030,000, which will be recognized over a weighted average period of 1.92 years.

Stock options

Under the 2008 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.

Under the 2012 Plan, 229,540 and 1,296,903 incentive stock options were issued during the three months ended September 30, 2013 and 2012, respectively, and 281,040 and 1,602,561 incentive stock options were issued during the six months ended September 30, 2013 and 2012, respectively, at various exercise prices, a quarter of which will vest on either the one year anniversary of employment or the one year anniversary of the vesting commencement date, ratably over the remaining 36 month terms and the remaining options vest immediately at the date of grant. The Company also issued 246,000 and 126,000 non-qualified stock option grants during the three months ended September 30, 2013 and 2012, respectively, and 291,500 and 126,000 non-qualified options were issued during the six months ended September 30, 2013 and 2012 respectively, which vest on the one year anniversary of the grant date or quarterly over three years.

A summary of the Company’s stock option activity for 2012 through September 30, 2013 is as follows:


	Options Outstanding			Weighted- Average Exercise Price		Aggregate Intrinsic Value
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		574,540		$	5.09
Options canceled		(10,855	)		3.85
Options exercised		(7,300	)	$	2.73	$	22,192

Outstanding at September 30, 2013		4,174,952		$	2.52	$	13,631,682

Vested and Exercisable at September 30, 2013		1,395,841		$	1.85	$	5,477,584

The weighted-average remaining contractual term of options exercisable and outstanding at September 30, 2013 was approximately 8.7 years and 8.9 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:


	Three Months Ended September 30, 2013			Three Months Ended September 30, 2012			Six Months Ended September 30, 2013			Six Months Ended September 30, 2012
Dividend yield		—			—			—			—
Volatility		82.6	%		96.21	%		84.82	%		80.49	%
Risk-free interest rate		0.63	%		0.816	%		0.842	%		1.012	%
Expected life of options		6.00 years			6.04 years			6.00 years			6.04 years
Weighted average grant date fair value	$	4.00		$	1.32		$	3.81		$	1.39

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 $1,155,000 and $244,000 for the three months ended September 30, 2013 and 2012, respectively, and $1,555,000 and $283,000 for the six months ended September 30, 2013 and 2012, respectively. The Company recorded stock-based compensation expense of approximately $2,534,000 for the period from April 19, 2007 (inception) through September 30, 2013. Expense included approximately $66,000 and $16,000 for research and development during the three months ended September 30, 2013 and 2012, respectively, and $133,000 and $51,000 for the six months ended September 30, 2013 and 2012, respectively. General and administrative expense was approximately $1,089,000 and $228,000 for the three months ended September 30, 2013 and 2012, respectively, and $1,422,000 and $232,000 for the six months ended September 30, 2013 and 2012, respectively.

The total unrecognized compensation cost related to unvested stock option grants as of September 30, 2013 was approximately $5,406,000 and the weighted average period over which these grants are expected to vest is 3.8 years.

Warrants

During the three months ended September 30, 2013 and 2012, 1,782,928 and 7,500 warrants were exercised through a cashless exercise provision for issuance of 1,427,351 and 4,772 shares of common stock, respectively. During the six months ended September 30, 2013 and 2012, 2,035,057 and 52,500 warrants were exercised through a cashless exercise provision for issuance of 1,627,486 and 42,356 shares of common stock, respectively. During the three and six months ended September 30, 2013, 243,500 warrants were exercised at prices of $2.28 and $3.24 for total proceeds of $651,180, and during the three and six months ended September 30, 2012, 1,668,475 and 1,768,475 warrants, respectively, were exercised at $1.00 for total proceeds of $1,668,475 and $1,768,475, respectively.

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.

1,782,928 and 1,668,475 of the warrants exercised during the three months ended September 30, 2013 and 2012, and 1,817,928 and 1,768,475 of the warrants exercised during the six months ended September 30, 2013 and 2012, respectively, were derivative liabilities and were valued at the settlement date. For the three months ended September 30, 2013 and 2012, and the six months ended September 30, 2013 and 2012, respectively, $10,018,000, $2,854,000, $10,147,000 and $3,728,000 of the warrant liability was removed due to the exercise of warrants. See Note 3.

During March 2013, the Company entered into amendment agreements for 600,065 warrants to purchase common stock which reduced the exercise price of the warrants from $1.00 to $0.90, extended the exercise term to five years from the effective date of the amendment, and 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 $65,000 was recognized as interest expense for the three months ended March 31, 2013.

During April 2013, the Company entered into amendment agreements for 269,657 warrants to purchase common stock which reduced the exercise price of the warrants from $1.00 to $0.85 and 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 of $767,000. 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 was recognized as interest expense for the six months ended September 30, 2013.

Additionally, 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 was 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 has been amortized over the term of the agreements. The Company recognized approximately $72,000 and $890,000 during the six months ended September 30, 2013 and for the period from April 19, 2007 (inception) through September 30, 2013, respectively, related to these services.

The following table summarizes warrant activity for 2012 through September 30, 2013:


	Warrants			Weighted- Average Exercise Price
Balance at December 31, 2011		2,909,750		$	1.00
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		—			—
Exercised		(2,278,557	)	$	1.18

Balance at September 30, 2013		2,005,332		$	1.15

The warrants outstanding at September 30, 2013 are immediately exercisable at prices between $0.85 and $2.28 per share, and have a weighted average remaining term of approximately 3.19 years.

Common stock reserved for future issuance

Common stock reserved for future issuance consisted of the following at September 30, 2013:


Common stock warrants outstanding			2,005,332
Common stock options outstanding under the 2008 Plan			672,192
Common stock options outstanding and reserved under the 2012 Plan			9,765,870

Total			12,443,394

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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+ Details

Commitments and Contingencies

6 Months Ended

Sep. 30, 2013

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

5. 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 with the future minimum lease payments from the current 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 condensed consolidated balance sheets.

Rent expense was approximately $105,000 and $105,000 for the three months ended September 30, 2013 and 2012, respectively, $210,000 and $157,000 for the six months ended September 30, 2013 and 2012, respectively, and $966,000 for the period from April 19, 2007 (inception) through September 30, 2013.

On February 27, 2012, the Company entered into a facilities lease at 6275 Nancy Ridge Drive, San Diego, CA 92121, with occupancy as of July 15, 2012. The base rent under the lease is approximately $38,800 per month with 3% annual escalators. The lease term is 48 months with an option for the Company to extend the lease at the end of the lease term.

Future minimum rental payments required under operating leases that have initial or remaining non-cancelable lease terms in excess of one year as of September 30, 2013, are as follows (in thousands):


Fiscal year ended March 31, 2014	$	242
Fiscal year ended March 31, 2015		493
Fiscal year ended March 31, 2016		506
Fiscal year ended March 31, 2017		170
Fiscal year ended March 31, 2018		—

Total	$	1,411

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 any such losses, damages or remedies may have on our condensed 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. On July 8, 2013, the Company filed a motion to stay the arbitration pending determination of the New York Action. On July 26, 2013, Spencer Trask filed a cross-motion to stay the New York Action pending conclusion of the arbitration. The Company’s motion and Spencer Trask’s cross-motion have been fully briefed. The court has not yet set a hearing date for the motion or cross-motion or issued a ruling.

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, including any arbitration matter filed 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. We have not accrued any loss contingencies for such matters. We intend to defend ourselves in any such matters and do not currently believe that the outcome of such matters will have a material adverse effect on our business, liquidity or financial position.

- Definition

The entire disclosure for significant arrangements with third parties, which includes operating lease arrangements and arrangements in which the entity has agreed to expend funds to procure goods or services, or has agreed to commit resources to supply goods or services, and operating lease arrangements. Descriptions may include identification of the specific goods and services, period of time covered, minimum quantities and amounts, and cancellation rights.

+ References+ Details

Concentrations	6 Months Ended
Concentrations	Sep. 30, 2013
Risks And Uncertainties [Abstract]
Concentrations	6. 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. 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.

- Definition

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

+ References+ Details

Subsequent Events	6 Months Ended
Subsequent Events	Sep. 30, 2013
Subsequent Events [Abstract]
Subsequent Events	7. Subsequent Events On October 8, 2013, Organovo, Inc. signed a Letter of Intent with ARE — SD Region No. 25, LLC, the current landlord, proposing to enter into a lease amendment to expand the leasable premises at its current location, 6275 Nancy Ridge Drive, San Diego, CA. Terms of the agreement have yet to be finalized.

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

6 Months Ended

Sep. 30, 2013

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

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 4).

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

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 September 30 and March 31, 2013 (in thousands):
	Balance at September 30, 2013		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	795		—		—	$	795

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

The following table presents the activity for liabilities measured at estimated fair value using unobservable inputs for 2012 through September 30, 2013:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)


	Warrant Derivative Liability ($000’s)
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		4,811
Warrant liability removal due to settlements		(10,147	)
Warrant liability reclassified to equity		(767	)

Balance at September 30, 2013	$	795

Research and Development

Research and development

Income Taxes

Income taxes

Revenue Recognition

Revenue recognition

The Company’s revenues are derived from collaborative research agreements, NIH and U.S. Treasury Department Grants, the sale of bioprinter related products and services, and license agreements.

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 Income (Loss) Per Share

Net income (loss) per share

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

6 Months Ended

Sep. 30, 2013

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 September 30 and March 31, 2013 (in thousands):
	Balance at September 30, 2013		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	795		—		—	$	795

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

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 2012 through September 30, 2013:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)


	Warrant Derivative Liability ($000’s)
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		4,811
Warrant liability removal due to settlements		(10,147	)
Warrant liability reclassified to equity		(767	)

Balance at September 30, 2013	$	795

- Definition

Tabular disclosure of liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, by class that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). Where the quoted price in an active market for the identical liability is not available, the Level 1 input is the quoted price of an identical liability when traded as an asset.

+ References+ Details

- Definition

Tabular disclosure of the fair value measurement of liabilities using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and gains or losses recognized in other comprehensive income (loss) and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs) by class of liability.

+ References+ Details

Derivative Liability (Tables)

6 Months Ended

Sep. 30, 2013

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:


	September 30, 2013			March 31, 2013			September 30, 2012
Closing price per share of common stock	$	5.77		$	3.68		$	2.05
Exercise price per share	$	1.00		$	1.00		$	1.00
Expected volatility		82.6	%		88.8	%		102.7	%
Risk-free interest rate		0.63	%		0.57	%		0.62	%
Dividend yield		—			—			—
Remaining expected term of underlying securities (years)		3.44			3.88			4.42

- Definition

Tabular disclosure of pertinent information about a derivative or group of derivatives on a disaggregated basis, such as for individual instruments, or small groups of similar instruments. May include a combination of the type of instrument, risks being hedged, notional amount, hedge designation, related hedged item, inception date, maturity date, or other relevant item.

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-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41638-113959

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

Reference 11: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(n)(2))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Stockholders' Equity (Tables)

6 Months Ended

Sep. 30, 2013

Equity [Abstract]

Summary of Company's Restricted Stock Award Activity

A summary of the Company’s restricted stock award activity for 2012 through September 30, 2013 is as follows:


	Number of Shares
Unvested at December 31, 2011		1,111,295
Granted		1,380,000
Vested		(1,143,735	)
Canceled / forfeited		(185,516	)

Unvested at December 31, 2012		1,162,044
Granted		55,000
Vested		(196,612	)
Canceled / forfeited		(34,690	)

Unvested at March 31, 2013		985,742
Granted		60,000
Vested		(356,250	)
Canceled / forfeited		—

Unvested at September 30, 2013		689,492

Summary of Stock Option Activity

A summary of the Company’s stock option activity for 2012 through September 30, 2013 is as follows:


	Options Outstanding			Weighted- Average Exercise Price		Aggregate Intrinsic Value
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		574,540		$	5.09
Options canceled		(10,855	)		3.85
Options exercised		(7,300	)	$	2.73	$	22,192

Outstanding at September 30, 2013		4,174,952		$	2.52	$	13,631,682

Vested and Exercisable at September 30, 2013		1,395,841		$	1.85	$	5,477,584

Fair Value of Employee Stock Options

The fair value of stock options was estimated at the grant date using the following weighted average assumptions:


	Three Months Ended September 30, 2013			Three Months Ended September 30, 2012			Six Months Ended September 30, 2013			Six Months Ended September 30, 2012
Dividend yield		—			—			—			—
Volatility		82.6	%		96.21	%		84.82	%		80.49	%
Risk-free interest rate		0.63	%		0.816	%		0.842	%		1.012	%
Expected life of options		6.00 years			6.04 years			6.00 years			6.04 years
Weighted average grant date fair value	$	4.00		$	1.32		$	3.81		$	1.39

Summary of Warrant Activity

The following table summarizes warrant activity for 2012 through September 30, 2013:


	Warrants			Weighted- Average Exercise Price
Balance at December 31, 2011		2,909,750		$	1.00
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		—			—
Exercised		(2,278,557	)	$	1.18

Balance at September 30, 2013		2,005,332		$	1.15

Common Stock Reserved for Future Issuance

Common stock reserved for future issuance consisted of the following at September 30, 2013:


Common stock warrants outstanding			2,005,332
Common stock options outstanding under the 2008 Plan			672,192
Common stock options outstanding and reserved under the 2012 Plan			9,765,870

Total			12,443,394

- Definition

Tabular disclosure of warrants or rights issued. Warrants and rights outstanding are derivative securities that give the holder the right to purchase securities (usually equity) from the issuer at a specific price within a certain time frame. Warrants are often included in a new debt issue to entice investors by a higher return potential. The main difference between warrants and call options is that warrants are issued and guaranteed by the company, whereas options are exchange instruments and are not issued by the company. Also, the lifetime of a warrant is often measured in years, while the lifetime of a typical option is measured in months. Disclose the title of issue of securities called for by warrants and rights outstanding, the aggregate amount of securities called for by warrants and rights outstanding, the date from which the warrants or rights are exercisable, and the price at which the warrant or right is exercisable.

+ References+ Details

Commitments and Contingencies (Tables)

6 Months Ended

Sep. 30, 2013

Commitments And Contingencies Disclosure [Abstract]

Future Minimum Rental Payments Required Under Operating Leases That Have Initial or Remaining Non-Cancellable 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 September 30, 2013, are as follows (in thousands):


Fiscal year ended March 31, 2014	$	242
Fiscal year ended March 31, 2015		493
Fiscal year ended March 31, 2016		506
Fiscal year ended March 31, 2017		170
Fiscal year ended March 31, 2018		—

Total	$	1,411

Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	1 Months Ended		6 Months Ended		77 Months Ended				1 Months Ended			6 Months Ended	1 Months Ended
	Aug. 31, 2013	Feb. 08, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Mar. 31, 2013	Feb. 07, 2012	Feb. 08, 2012 Convertible Notes Payable [Member]	Mar. 16, 2012 Merger transition [Member]	Feb. 29, 2012 Merger transition [Member]	Feb. 08, 2012 Merger transition [Member]	Sep. 30, 2013 Merger transition [Member] Private_placement	Feb. 08, 2012 Merger transition [Member] Outstanding Principal Assumed On Acquisition [Member]	Feb. 08, 2012 Merger transition [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		$ 0.001	$ 0.001		$ 0.001	$ 0.001
Former security holders common stock voting interest			75.00%
Company's stockholders retained voting interest			25.00%
Conversion ratio into common stock on merger							0.0001
Number of private placement transactions												3
Total gross proceeds of approximately									$ 6,900,000	$ 1,800,000	$ 5,000,000
Proceeds from issuance of convertible notes payable		1,500,000			4,630,000
Convertible notes, interest rate								6.00%
Convertible notes converted into shares of common stock													1,500,000	25,387
Accrued interest		25,387			485,000
Cash transaction costs related to the Merger approximately			2,100,000
Accumulated deficit			80,522,000		80,522,000	66,365,000
Cash flow from operations			(6,256,000)	(4,159,000)	(22,034,000)
Net proceeds to company from offering	$ 43,400,000
Sale of common stock in a public offering	10,350,000

Description of Business and Summary of Significant Accounting Policies - Additional Information I (Detail) (USD $) Share data in Millions, unless otherwise specified	3 Months Ended		6 Months Ended		77 Months Ended			6 Months Ended	12 Months Ended	3 Months Ended		6 Months Ended		37 Months Ended	77 Months Ended	1 Months Ended	3 Months Ended		6 Months Ended			1 Months Ended	77 Months Ended	6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2013 U.S. Treasury [Member]	Dec. 31, 2010 U.S. Treasury [Member] Grants	Sep. 30, 2013 NHLBI [Member]	Sep. 30, 2012 NHLBI [Member]	Sep. 30, 2013 NHLBI [Member]	Sep. 30, 2012 NHLBI [Member]	Dec. 31, 2012 NHLBI [Member] Grants	Sep. 30, 2013 NHLBI [Member]	Oct. 31, 2011 Research and Development Services [Member]	Sep. 30, 2013 Research and Development Services [Member]	Sep. 30, 2012 Research and Development Services [Member]	Sep. 30, 2013 Research and Development Services [Member]	Sep. 30, 2012 Research and Development Services [Member]	Mar. 31, 2013 Research and Development Services [Member]	Dec. 31, 2010 12 month research contract agreement [Member]	Sep. 30, 2013 12 month research contract agreement [Member]	Sep. 30, 2013 Maximum [Member]	Sep. 30, 2013 Minimum [Member]
Significant Accounting Policies Related To Business Acquisition Revenue Recognition And Earnings Per Share [Line Items]
Maturity of highly liquid investment																								90 days
Restricted Cash	$ 38,000		$ 38,000		$ 38,000	$ 88,000
Restricted cash							38,300
Additional restricted cash						50,000
Inventory of raw materials	74,000		74,000		74,000	88,000
Obsolete inventory reserve	0		0		0	0
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					0
Deferred revenue related to its collaborative research programs	75,000		75,000		75,000	53,000											81,000		81,000		62,000
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	23,000	469,000	129,000	728,000	3,192,000												1,335,500						600,000
Initial payment to the Company from Agreement																239,000
Remaining payments expected to occur over																21 months
Fee for additional research and development services	135,000		135,000
Total contract value	1,500,000		1,500,000
Maximum amendment extended period remaining for payment of additional research and development services																			28 months
Revenue related to research contract																	22,000	299,000	115,000	558,000
Number of grants issued									2					3
Grants		$ 95,000	$ 12,000	$ 95,000	$ 955,000			$ 397,000		$ 0	$ 95,000	$ 12,000	$ 95,000	$ 558,000	$ 558,000
Total common stock equivalents	6.9	11.7	6.9	15.7

Description of Business and Summary of Significant Accounting Policies - Estimated Fair Values of Liabilities Measured on Recurring Basis (Detail) (Warrant [Member], USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	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	$ 795	$ 6,898
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	795	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	$ 795	$ 6,898

- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References+ Details

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		6 Months Ended		77 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Mar. 31, 2013 Significant Other Unobservable Inputs (Level 3) [Member] Warrant [Member]	Sep. 30, 2013 Significant Other Unobservable Inputs (Level 3) [Member] Warrant [Member]	Dec. 31, 2012 Significant Other Unobservable Inputs (Level 3) [Member] Warrant [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Warrant Derivative Liability, Beginning balance						$ 20,619,000	$ 6,898,000	$ 1,267,000
Issuances								32,742,000
Adjustments to estimated fair value	4,787,000	(42,252,000)	4,811,000	(8,315,000)	26,782,000	12,034,000	4,811,000	9,931,000
Warrant liability removal due to settlements						(23,869,000)	(10,147,000)	(23,321,000)
Warrant liability reclassified to equity			(767,000)		(2,653,000)	(1,886,000)	(767,000)
Warrant Derivative Liability, Ending balance						$ 6,898,000	$ 795,000	$ 20,619,000

- Definition

+ References+ Details

Derivative Liability - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended		3 Months Ended			6 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012 Private_placement	Mar. 31, 2013	Sep. 30, 2013 Warrant [Member]	Sep. 30, 2012 Warrant [Member]	Dec. 31, 2011 Warrant [Member]	Sep. 30, 2013 Warrant [Member]	Sep. 30, 2012 Warrant [Member]	Dec. 31, 2012 Warrant [Member]
Derivative [Line Items]
Number of offerings under private placement reverse merger					3
Warrants Issued									1,500,000			21,347,182
Warrants maturity term					5 years
Fair value of the warrant liabilities									$ 1.3			$ 32.7
Estimated fair value of the outstanding warrant liabilities	0.8		0.8			6.9
Change in fair value of the derivative liabilities increase and decrease	$ 4.8	$ 42.3	$ 4.8	$ 8.3
Exercised derivative liabilities							1,782,928	1,668,475		1,817,928	1,768,475
Reclassification of warrant							269,657			269,657

- Definition

Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset against a right to receive collateral under a master netting arrangement.

+ References+ Details

Derivative Liability - Assumptions Used to Value Derivative Liabilities at Closing Dates of Private Placements (Detail) (Warrant Derivative Liability [Member], USD $)	3 Months Ended	6 Months Ended
	Mar. 31, 2013	Sep. 30, 2013	Sep. 30, 2012
Warrant Derivative Liability [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Closing price per share of common stock	$ 3.68	$ 5.77	$ 2.05
Exercise price per share	$ 1.00	$ 1.00	$ 1.00
Expected volatility	88.80%	82.60%	102.70%
Risk-free interest rate	0.57%	0.63%	0.62%
Dividend yield
Remaining expected term of underlying securities (years)	3 years 10 months 17 days	3 years 5 months 9 days	4 years 5 months 1 day

Stockholders' Equity - Additional Information (Detail) (USD $)	3 Months Ended			6 Months Ended		12 Months Ended		3 Months Ended		6 Months Ended		48 Months Ended	77 Months Ended	6 Months Ended		12 Months Ended	48 Months Ended				3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		48 Months Ended	0 Months Ended
	Sep. 30, 2013	Mar. 31, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Aug. 02, 2013	Sep. 30, 2013 Restricted stock [Member]	Sep. 30, 2012 Restricted stock [Member]	Sep. 30, 2013 Restricted stock [Member]	Sep. 30, 2012 Restricted stock [Member]	Dec. 31, 2011 Restricted stock [Member]	Sep. 30, 2013 Restricted stock [Member]	Sep. 30, 2013 Restricted Stock Units (RSUs) [Member]	Sep. 30, 2013 Equity Incentive Plan 2008 [Member]	Dec. 31, 2012 Equity Incentive Plan 2008 [Member]	Dec. 31, 2011 Equity Incentive Plan 2008 [Member]	May 31, 2013 Equity Incentive Plan 2008 [Member]	Aug. 31, 2013 Equity Incentive Plan 2012 [Member]	Jan. 31, 2012 Equity Incentive Plan 2012 [Member]	Sep. 30, 2013 Research and development expense [Member]	Sep. 30, 2012 Research and development expense [Member]	Sep. 30, 2013 Research and development expense [Member]	Sep. 30, 2012 Research and development expense [Member]	Sep. 30, 2013 General and administrative expense [Member]	Sep. 30, 2012 General and administrative expense [Member]	Sep. 30, 2013 General and administrative expense [Member]	Sep. 30, 2012 General and administrative expense [Member]	Dec. 31, 2011 Other Plan [Member] Restricted stock [Member]	Aug. 02, 2013 Underwriting Agreement [Member]	Jul. 17, 2013 Underwriting Agreement [Member]	Aug. 02, 2013 Underwriting Agreement [Member] Over Allotment Option Exercised [Member]
Class of Stock [Line Items]
Shares authorized under shelf registration statement	150,000,000	150,000,000		150,000,000																											100,000,000
Issuance of Common stock	76,818,625	64,686,919		76,818,625																										10,350,000		1,350,000
Offering price per share							$ 4.5																							$ 4.23
Proceeds from issuance of common stock																														$ 43,400,000
Underwriting discounts and commissions and other offering expenses																														3,100,000
Number of shares issuable upon exercise of warrant	1,670,851		1,673,247	1,870,986	1,810,831
Number of warrant exercised	2,026,428		1,675,975	2,278,557	1,820,975
Common shares authorized to be issued																		1,521,584	5,000,000	6,553,986
Shares issued during the year															0	0
Termination date of Equity Incentive Plan															Jul. 01, 2018
Restricted common stock to founders												1,258,934					1,086,662												172,272
Termination date of Equity Incentive Plan				10 years
Shares available for Issuance																			11,553,996
Restricted stock Issued									1,380,000		1,380,000
Restricted stock cancelled		34,690				185,516
Issuance restricted Common stock to certain employees, advisors and consultants		55,000		60,000		1,380,000								60,000
Restricted stock cancelled	160,540
Restricted stock units vested during the period	296,250	196,612		356,250		1,143,735
Stock options granted	160,540	927,981		574,540		2,023,394
Total employee stock-based compensation recorded as operating expenses								131,000	998,000	533,000	998,000		1,854,000								4,000	84,000	8,000	84,000	127,000	914,000	525,000	914,000
Unrecognized stock-based compensation expense								$ 1,030,000		$ 1,030,000			$ 1,030,000
Unrecognized stock-based compensation expense recognition maximum weighted average period										1 year 11 months 1 day

Stockholders' Equity - Summary of Company's Restricted Stock Award Activity (Detail)	3 Months Ended		6 Months Ended	12 Months Ended
	Sep. 30, 2013	Mar. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Beginning balance, Unvested, Number of Shares		1,162,044	985,742	1,111,295
Granted, Number of Shares		55,000	60,000	1,380,000
Vested, Number of Shares	(296,250)	(196,612)	(356,250)	(1,143,735)
Canceled / forfeited, Number of Shares		(34,690)		(185,516)
Ending balance, Unvested, Number of Shares	689,492	985,742	689,492	1,162,044

Stockholders' Equity - Additional Information 1 (Detail) (USD $)	3 Months Ended		6 Months Ended	12 Months Ended	3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		77 Months Ended	3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended				1 Months Ended	6 Months Ended	3 Months Ended		6 Months Ended		3 Months Ended
	Sep. 30, 2013	Mar. 31, 2013	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Research and development expense [Member]	Sep. 30, 2012 Research and development expense [Member]	Sep. 30, 2013 Research and development expense [Member]	Sep. 30, 2012 Research and development expense [Member]	Sep. 30, 2013 General and administrative expense [Member]	Sep. 30, 2012 General and administrative expense [Member]	Sep. 30, 2013 General and administrative expense [Member]	Sep. 30, 2012 General and administrative expense [Member]	Sep. 30, 2013 Stock options [Member]	Sep. 30, 2012 Stock options [Member]	Sep. 30, 2013 Stock options [Member]	Sep. 30, 2012 Stock options [Member]	Sep. 30, 2013 Stock options [Member]	Sep. 30, 2013 Stock options [Member] Research and development expense [Member]	Sep. 30, 2012 Stock options [Member] Research and development expense [Member]	Sep. 30, 2013 Stock options [Member] Research and development expense [Member]	Sep. 30, 2012 Stock options [Member] Research and development expense [Member]	Sep. 30, 2013 Stock options [Member] General and administrative expense [Member]	Sep. 30, 2012 Stock options [Member] General and administrative expense [Member]	Sep. 30, 2013 Stock options [Member] General and administrative expense [Member]	Sep. 30, 2012 Stock options [Member] General and administrative expense [Member]	Sep. 30, 2013 2008 Plan [Member]	Oct. 12, 2011 2008 Plan [Member]	Oct. 12, 2011 2008 Plan [Member] Stock options [Member]	Sep. 30, 2013 2008 Plan [Member] Stock options [Member]	Sep. 30, 2013 2012 Plan [Member]	Sep. 30, 2012 2012 Plan [Member]	Sep. 30, 2013 2012 Plan [Member]	Sep. 30, 2012 2012 Plan [Member]	Sep. 30, 2013 2012 Plan [Member] Stock options [Member]
Class of Stock [Line Items]
Equity Incentive Plan, shares	160,540	927,981	574,540	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 the one year anniversary of the vesting commencement date
Remaining options vest																										36 months						36 months
Issuances of Common stock from stock option exercises, Shares			7,300	224,064																										229,540	1,296,903	281,040	1,602,561
Stock option granted, Restricted portion																														246,000	126,000	291,500	126,000
Stock option granted, Quarterly vesting restricted term																																3 years
Weighted average remaining contractual term of options exercisable			8 years 8 months 12 days
Weighted average remaining contractual term of options outstanding			8 years 10 months 24 days
Total employee stock-based compensation recorded as operating expenses					$ 4,000	$ 84,000	$ 8,000	$ 84,000	$ 127,000	$ 914,000	$ 525,000	$ 914,000	$ 1,155,000	$ 244,000	$ 1,555,000	$ 283,000	$ 2,534,000	$ 66,000	$ 16,000	$ 133,000	$ 51,000	$ 1,089,000	$ 228,000	$ 1,422,000	$ 232,000
Total unrecognized compensation cost related to unvested stock option grants	$ 5,406,000		$ 5,406,000
Total unrecognized compensation cost related to unvested stock option grants, weighted average period															3 years 9 months 18 days

Stockholders' Equity - Summary of Stock Option Activity (Detail) (USD $)	3 Months Ended		6 Months Ended	12 Months Ended
	Sep. 30, 2013	Mar. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Options Outstanding, Beginning balance		2,690,586	3,618,567	896,256
Granted, Options Outstanding	160,540	927,981	574,540	2,023,394
Canceled, Options Outstanding			(10,855)	(5,000)
Exercised, Options Outstanding			(7,300)	(224,064)
Options Outstanding, Ending balance	4,174,952	3,618,567	4,174,952	2,690,586
Weighted-Average Exercise Price, Options Beginning balance		$ 1.48	$ 2.11	$ 0.08
Vested and Exercisable, Options Outstanding	1,395,841		1,395,841
Options granted, Weighted-Average Exercise Price		$ 3.93	$ 5.09	$ 1.95
Options canceled, Weighted-Average Exercise Price			$ 3.85	$ 2.25
Options exercised, Weighted-Average Exercise Price			$ 2.73	$ 0.08
Weighted-Average Exercise Price, Options Ending balance	$ 2.52	$ 2.11	$ 2.52	$ 1.48
Aggregate Intrinsic Value, Options Beginning balance		$ 3,041,476	$ 5,909,154
Vested and Exercisable, Weighted-Average Exercise Price	$ 1.85		$ 1.85
Options Exercised, Aggregate Intrinsic Value			22,192	564,641
Aggregate Intrinsic Value, Options Ending balance	13,631,682	5,909,154	13,631,682	3,041,476
Vested and Exercisable at September 30, 2013	$ 5,477,584		$ 5,477,584

Stockholders' Equity - Fair Value of Employee Stock Options (Detail) (USD $)	3 Months Ended		6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Dividend yield
Volatility	82.60%	96.21%	84.82%	80.49%
Risk-free interest rate	0.63%	0.816%	0.842%	1.012%
Expected life of options	6 years	6 years 15 days	6 years	6 years 15 days
Weighted average grant date fair value	$ 4.00	$ 1.32	$ 3.81	$ 1.39

Stockholders' Equity - Additional Information 2 (Detail) (USD $)	1 Months Ended	3 Months Ended			6 Months Ended		12 Months Ended		77 Months Ended
	Dec. 31, 2012	Sep. 30, 2013	Mar. 31, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012 Agreement	Dec. 31, 2011	Sep. 30, 2013	Apr. 30, 2013
Class of Stock [Line Items]
Number of warrant exercised through cashless		1,782,928		7,500	2,035,057	52,500
Cashless exercise for issuance of common stock		1,427,351		4,772	1,627,486	42,356
Number of warrant exercised		2,026,428		1,675,975	2,278,557	1,820,975
Warrants exercisable price, per share	1.00						1.00
Outstanding warrants to purchase							14,500,000
Exercise price of warrant Amended	$ 0.80						$ 0.80
Warrant proceeds							9,600,000
Aggregate proceeds of warrants tendered	7,700,000								32,743,000
Recognized expenses of warrants							1,900,000
Costs incurred related to warrant exercises							400,000
Number of warrant exercised during period recorded as derivative liability		1,782,928		1,668,475	1,817,928	1,768,475
Warrants liability		10,018,000		2,854,000	10,147,000	3,728,000
Warrants to purchase common stock	650,000		600,065				650,000			269,657
Life of warrants			5 years
Interest Expense					13,000				3,484,000
Exercise price of warrants before amendment										1.00
Exercise price of warrants after amendment										0.85
Warrants reclassified to additional paid in capital					767,000		890,000	1,111,000
Number of agreement with consultants							4
Volatility rate		82.60%		96.21%	84.82%	80.49%
Risk free factor		0.63%		0.816%	0.842%	1.012%
Recognized expenses of warrants					72,000				890,000
Weighted average remaining contractual term of options exercisable					8 years 8 months 12 days
Minimum [Member]
Class of Stock [Line Items]
Warrants exercisable price, per share		0.85	0.90		0.85				0.85
Life of warrants							2 years
Maximum [Member]
Class of Stock [Line Items]
Warrants exercisable price, per share		2.28	1.00		2.28				2.28
Life of warrants							5 years
Warrant [Member]
Class of Stock [Line Items]
Number of warrant exercised		243,500		1,668,475	243,500	1,768,475
Warrants exercisable price, per share		3.24		1.00	3.24	1.00			3.24
Proceeds from warrant exercise		651,180		1,668,475	651,180	1,768,475
Interest Expense			65,000		12,000
Estimated fair value of warrants							$ 890,000
Weighted average remaining contractual term of options exercisable					3 years 2 months 9 days
Warrant [Member] \| Minimum [Member]
Class of Stock [Line Items]
Warrants exercisable price, per share	1.70						1.70
Volatility rate							79.80%
Risk free factor							0.24%
Warrant [Member] \| Maximum [Member]
Class of Stock [Line Items]
Warrants exercisable price, per share	3.24						3.24
Volatility rate							103.80%
Risk free factor							0.63%

Stockholders' Equity - Summary of Warrant Activity (Detail) (USD $)	3 Months Ended		6 Months Ended	12 Months Ended
	Sep. 30, 2013	Mar. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
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	160,540	927,981	574,540	2,023,394
Exercised, Options Outstanding			(7,300)	(224,064)
Options Outstanding, Ending balance	4,174,952	3,618,567	4,174,952	2,690,586
Weighted-Average Exercise Price, Options Beginning balance		$ 1.48	$ 2.11	$ 0.08
Granted, Weighted-Average Exercise Price		$ 3.93	$ 5.09	$ 1.95
Exercised, Weighted-Average Exercise Price			$ 2.73	$ 0.08
Weighted-Average Exercise Price, Options Ending balance	$ 2.52	$ 2.11	$ 2.52	$ 1.48
Warrant [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				21,997,182
Exercised, Options Outstanding		(7,090,556)	(2,278,557)	(13,532,487)
Options Outstanding, Ending balance	2,005,332	4,283,889	2,005,332	11,374,445
Weighted-Average Exercise Price, Options Beginning balance		$ 1.08	$ 1.17	$ 1.00
Granted, Weighted-Average Exercise Price				$ 1.04
Exercised, Weighted-Average Exercise Price		$ 1.01	$ 1.18	$ 0.84
Weighted-Average Exercise Price, Options Ending balance	$ 1.15	$ 1.17	$ 1.15	$ 1.08

- Definition

Number of share options (or share units) exercised during the current period.

+ References+ Details

Stockholders' Equity - Common Stock Reserved for Future Issuance (Detail)	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	12,443,394
Warrant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	2,005,332
Equity Incentive Plan 2008 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	672,192
Equity Incentive Plan 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	9,765,870

Commitments and Contingencies - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended		77 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]
Rent expense	$ 105,000	$ 105,000	$ 210,000	$ 157,000	$ 966,000
Base rent under the lease	$ 38,800		$ 38,800		$ 38,800
Base rent escalators	3.00%		3.00%		3.00%
Lease term with option to extend			48 months

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 $) In Thousands, unless otherwise specified	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]
Fiscal year ended March 31, 2014	$ 242
Fiscal year ended March 31, 2015	493
Fiscal year ended March 31, 2016	506
Fiscal year ended March 31, 2017	170
Fiscal year ended March 31, 2018
Total	$ 1,411

Change in Fiscal Year End	6 Months Ended
Change in Fiscal Year End	Sep. 30, 2013
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 31^st to March 31^st. 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 fiscal years mean the fiscal year ending March 31^st of that calendar year.