Document and Entity Information	6 Months Ended
Document and Entity Information	Sep. 30, 2015	Oct. 30, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2016
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	Accelerated Filer
Entity Common Stock, Shares Outstanding		92,413,710

Condensed Consolidated Balance Sheets (USD $)	Sep. 30, 2015	Mar. 31, 2015
Current Assets
Cash and cash equivalents	$ 76,863,000	$ 50,142,000
Accounts receivable	180,000	0
Inventory	68,000	66,000
Prepaid expenses and other current assets	714,000	1,054,000
Total current assets	77,825,000	51,262,000
Fixed assets, net	3,633,000	2,042,000
Restricted cash	78,800	78,800
Other assets, net	139,000	106,000
Total assets	81,676,000	53,489,000
Current Liabilities
Accounts payable	567,000	1,387,000
Accrued expenses	2,421,000	2,257,000
Deferred rent	1,112,000	759,000
Deferred revenue	1,402,000	227,000
Capital lease obligation	0	5,000
Warrant liabilities	16,000	126,000
Total current liabilities	5,518,000	4,761,000
Deferred revenue, net of current portion	7,000	32,000
Capital lease obligation, net of current portion	0	0
Total liabilities	5,525,000	4,793,000
Commitments and Contingencies (Note 4)	0	0
Stockholders’ Equity
Common stock, $0.001 par value; 150,000,000 shares authorized, 92,327,772 and 81,536,724 shares issued and outstanding at September 30, 2015 and March 31, 2015, respectively	92,000	82,000
Additional paid-in capital	218,102,000	170,909,000
Accumulated deficit	(142,043,000)	(122,295,000)
Total stockholders’ equity	76,151,000	48,696,000
Total Liabilities and Stockholders’ Equity	$ 81,676,000	$ 53,489,000

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2015	Mar. 31, 2015
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	92,327,772	81,536,724
Common stock, shares outstanding	92,327,772	81,536,724

Unaudited Condensed Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenues
Product and service	$ 187	$ 0	$ 396	$ 0
Collaborations	19	45	33	114
Grants	95	5	178	35
Total Revenues	301	50	607	149
Selling, general, and administrative expenses	6,846	5,777	11,468	9,472
Research and development expenses	4,739	3,229	8,881	6,043
Loss from Operations	(11,284)	(8,956)	(19,742)	(15,366)
Other Income (Expense)
Change in fair value of warrant liabilities	9	94	(28)	64
Loss on disposals of fixed assets	0	(3)	0	(3)
Interest income	18	7	25	14
Total Other Income (Expense)	27	98	(3)	75
Income Tax Expense	0	0	(3)	0
Net Loss	$ (11,257)	$ (8,858)	$ (19,748)	$ (15,291)
Net loss per common share—basic and diluted	$ (0.12)	$ (0.11)	$ (0.23)	$ (0.19)
Weighted average shares used in computing net loss per common share—basic and diluted	92,385,150	78,933,884	87,715,217	78,589,521

Unaudited Condensed Consolidated Statements of Cash Flows (USD $)	6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash Flows From Operating Activities
Net loss	$ (19,748,000)	$ (15,291,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Loss on disposal of fixed assets	0	3,000
Depreciation and amortization	324,000	208,000
Change in fair value of warrant liabilities	28,000	(64,000)
Stock-based compensation	3,952,000	3,634,000
Amortization of warrants issued for services	(105,000)	469,000
Increase (decrease) in cash resulting from changes in:
Accounts receivable	(180,000)	(30,000)
Inventory	(2,000)	(7,000)
Prepaid expenses and other assets	337,000	113,000
Accounts payable	(820,000)	204,000
Accrued expenses	164,000	737,000
Deferred rent	(21,000)	223,000
Deferred revenue	1,150,000	124,000
Net cash used in operating activities	(14,921,000)	(9,677,000)
Cash Flows From Investing Activities
Purchases of fixed assets	(1,550,000)	(576,000)
Proceeds from disposals of fixed assets	14,000	0
Purchases of intangible assets	(35,000)	0
Net cash used in investing activities	(1,571,000)	(576,000)
Cash Flows From Financing Activities
Proceeds from issuance of common stock and exercise of warrants, net	43,137,000	16,291,000
Proceeds from exercise of stock options	81,000	188,000
Principal payments on capital lease obligations	(5,000)	(4,000)
Net cash provided by financing activities	43,213,000	16,475,000
Net Increase (Decrease) in Cash and Cash Equivalents	26,721,000	6,222,000
Cash and Cash Equivalents at Beginning of Period	50,142,000	48,167,000
Cash and Cash Equivalents at End of Period	76,863,000	54,389,000
Supplemental Disclosure of Cash Flow Information:
Interest	0	0
Income Taxes	$ (3,000)	$ 0

Description of Business and Summary of Significant Accounting Policies

6 Months Ended

Sep. 30, 2015

Accounting Policies [Abstract]

Description of Business and Summary of Significant Accounting Policies

Note 1. 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 subsidiaries. The Company is an early commercial stage company, focused on 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.

Since its inception, the Company has devoted its efforts primarily to developing and commercializing a platform technology and functional human tissues that can be employed in drug discovery and development, biological research, and as therapeutic implants for the treatment of damaged or degenerating tissues and organs. The Company has also focused efforts on raising capital and building infrastructure. In November 2014, the Company announced the full commercial release of its first product, the exVive3D ™ Human Liver Tissue for use in toxicology and other preclinical drug testing. As of September 30, 2015, the Company has not yet realized significant revenues from its planned principal operations. The Company’s activities are subject to significant risks and uncertainties including failing to successfully develop products and services based on its technology and to achieve the market acceptance necessary to generate sufficient revenues and to achieve and sustain profitability.

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 and cash flows in accordance with generally accepted accounting principles (“GAAP”). The balance sheet at March 31, 2015 is derived from the Company’s 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 and cash flows. These financial statements should be read in conjunction with the financial statements included in the Company’s Annual Report filed on Form 10-K for the year ended March 31, 2015 filed with the Securities and Exchange Commission (the “SEC”) on June 9, 2015. Operating results for interim periods are not necessarily indicative of operating results for the Company’s fiscal year ending March 31, 2016.

NYSE MKT Listing

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

Liquidity

As of September 30, 2015, the Company had an accumulated deficit of approximately $142.0 million. The Company also had negative cash flows from operations of approximately $14.9 million during the six months ended September 30, 2015.

Through September 30, 2015, 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, product sales, collaborative research agreements and research service 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.

On June 23, 2015, the Company closed an underwritten public offering in which it sold an aggregate of 10,838,750 shares of common stock and raised gross proceeds of approximately $46.1 million. The Company’s future capital needs will depend on the revenues it generates through its commercialization efforts and the cash it elects to spend to pursue its product development efforts and implement its business plan. As a result, the Company cannot predict with certainty when it may be required to secure additional capital to fund its future operations.

The Company intends to cover its future operating expenses through cash on hand, through revenue derived from grants, product sales, collaborative research agreements and research services agreements and through the issuance of additional equity or debt securities. Depending on market conditions, we cannot be sure that additional financing will be available when needed or that, if available, financing will be obtained on terms favorable to us or to our stockholders.

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

Use of estimates

The preparation of the financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect certain reported amounts and disclosures. Accordingly, actual results could differ from those estimates. Significant estimates used in preparing the 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, accounts receivable, inventory, prepaid expenses and other current 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, 2015 and March 31, 2015, the Company had approximately $78,800 of restricted cash deposited with a financial institution. The entire amount is held in certificates of deposit to support a letter of credit agreement related to the Company’s facility lease.

Inventory

Inventories are stated at the lower of the cost or market (first-in, first-out). Inventory consisted of approximately $68,000 and $66,000 in raw materials as of September 30, 2015 and March 31, 2015, respectively, net of reserves. The Company provides inventory allowances based on excess or obsolete inventories determined based on anticipated use in the final product. The reserve for obsolete inventory at September 30, 2015 and March 31, 2015 was approximately $32,000 and $31,000, respectively.

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 remaining lease term. The estimated useful lives of the fixed assets range between three and seven 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 has occurred through September 30, 2015.

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 2). 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 may have an impact on the computed fair value of the warrant liability.

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

	Fair Value Measurements at September 30 and March 31, 2015 (in thousands):
	Balance at September 30, 2015		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	16		—		—	$	16

	Balance at March 31, 2015		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	126		—		—	$	126

The following table presents the activity for liabilities measured at estimated fair value using unobservable inputs for the six months ended September 30, 2015:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

	Warrant Derivative Liability (in thousands)
Balance at March 31, 2015	$	126
Issuances		—
Adjustments to estimated fair value		28
Warrant liability removal due to settlements		(138	)
Warrant liability reclassified to equity		—
Balance at September 30, 2015	$	16

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 research service agreements, product sales, collaborative research agreements, and grants from the National Institutes of Health (“NIH”), U.S. Treasury Department and private not-for-profit organizations.

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, 2015 and March 31, 2015, the Company had approximately $1,409,000 and $259,000, respectively, in deferred revenue related to its grants, collaborative research programs and research service agreements.

Revenue arrangements with multiple deliverables

The Company follows ASC 605-25 Revenue Recognition – Multiple-Element Arrangements for 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.

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 periodically receives 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.

Product revenue

The Company recognizes product revenue at the time of shipment to the customer, provided all other revenue recognition criteria have been met. To date, the Company has not recognized significant revenue from commercial product sales.

As our commercial sales increase, we expect to establish a reserve for estimated product returns that will be recorded as a reduction to revenue. This reserve will be maintained to account for future return of products sold in the current period. The reserve will be reviewed quarterly and will be estimated based on an analysis of our historical experience related to product returns.

Revenue from research service agreements

For research service agreements that contain only a single or primary deliverable, the Company defers any up-front fees collected from customers, and recognizes revenue for the delivered element only when it determines there are no uncertainties regarding customer acceptance. For agreements that contain multiple deliverables, the Company follows ASC 605-25 as described above. During the six months ended September 30, 2015, the Company received a $1,000,000 up-front fee from a customer. As there were no delivered elements during the first two quarters, this amount remains in deferred revenue as of September 30, 2015.

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 up-front 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 services are provided or substantive milestones are achieved. We recognize revenue that is contingent upon the achievement of a substantive milestone in its entirety in the period in which the milestone is achieved. A milestone is considered substantive when the consideration payable to us for the milestone (i) is consistent with our performance necessary to achieve the milestone or the increase in value to the collaboration resulting from our performance, (ii) relates solely to our past performance and (iii) is reasonable relative to all of the other deliverables and payments within the arrangement. In making this assessment, we consider all facts and circumstances relevant to the arrangement, including factors such as the risks that must be overcome to achieve the milestone, the level of effort and investment required to achieve the milestone and whether any portion of the milestone consideration is related to future performance or deliverables.

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, using the appropriate method of revenue recognition based on its analysis of the related contractual element(s).

Grant revenues

During August 2013, the Company was awarded a research grant by a private, not-for-profit organization for up to $251,700, contingent on go/no-go decisions made by the grantor at the completion of each stage of research as outlined in the grant award. Revenues from the grant are based upon internal costs incurred that are specifically covered by the grant, plus an additional rate that provides funding for overhead expenses. Revenue is recognized when the Company incurs expenses that are related to the grant. Revenue recognized under this grant was approximately $21,000 and $30,000 for the three and six months ended September 30, 2015, respectively. Revenue recognized under this grant was approximately $5,000 and $35,000 for the three and six months ended September 30, 2014, respectively.

During September 2014, the NIH awarded the Company a research grant totaling approximately $222,000. The grant provides for fixed payments based on the achievement of certain milestones. As such, revenue will be recognized upon completion of substantive milestones. Revenue recognized under this grant was approximately $74,000 and $148,000 for the three and six months ended September 30, 2015, respectively. Grant activities did not commence until the third quarter of fiscal 2015 and therefore no revenue was recognized under this grant as of September 30, 2014.

Stock-based compensation

The Company accounts for stock-based compensation in accordance with the Financial Accounting Standards Board’s (“FASB”) 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, 2015 and 2014, respectively, the comprehensive loss was equal to the net loss.

Net loss per share

Basic and diluted net loss per share has been computed using the weighted-average number of shares of common stock outstanding during the period. The weighted-average number of shares used to compute diluted loss per share excludes any assumed exercise of stock options and warrants, the assumed release of restriction of restricted stock units, and shares subject to repurchase as the effect would be anti-dilutive. No dilutive effect was calculated for the three and six months ended September 30, 2015 or 2014, as the Company reported a net loss for each respective period and the effect would have been anti-dilutive. Common stock equivalents excluded from computing diluted net loss per share were approximately 10.5 million for the three and six months ended September 30, 2015, and 7.9 million for the three and six months ended September 30, 2014.

Derivative Liability

6 Months Ended

Sep. 30, 2015

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Derivative Liability

Note 2. Derivative Liability

During 2011 and 2012, the Company issued five-year warrants to purchase its common stock. For certain of these warrants, the exercise price 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 was recorded as a derivative liability on the issuance dates.

The Company revalues the warrants classified as derivative liabilities as of the end of each reporting period. The estimated fair value of the outstanding warrant liabilities was less than $0.1 million and approximately $0.1 million as of September 30, 2015 and March 31, 2015, respectively. The changes in fair value of the derivative liabilities were decreases of approximately $9,000 and $94,000 for the three months ended September 30, 2015 and 2014, respectively, and an increase of approximately $28,000 and a decrease of approximately $64,000 for the six months ended September 30, 2015 and 2014, respectively, and are included in other income (expense) in the statements of operations.

During the three months ended September 30, 2015 and 2014, no warrants that were classified as derivative liabilities were exercised. During the six months ended September 30, 2015 and 2014, 38,234 and 8,647 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.

The derivative liabilities were valued at the end of each reporting period using a Monte Carlo valuation model with the following assumptions:

	September 30, 2015			March 31, 2015			September 30, 2014
Closing price per share of common stock	$	2.68		$	3.54		$	6.37
Exercise price per share	$	1.00		$	1.00		$	1.00
Expected volatility		71.60	%		76.80	%		76.50	%
Risk-free interest rate		0.33	%		0.56	%		0.58	%
Dividend yield		—			—			—
Remaining expected term of underlying securities (years)		1.46			1.96			2.46

- 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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-URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41641-113959

+ Details

Stockholders' Equity

6 Months Ended

Sep. 30, 2015

Equity [Abstract]

Stockholders' Equity

Note 3. Stockholders’ Equity

Common stock

The Company filed a shelf registration statement on Form S-3 (File No. 333-189995), or the 2013 Shelf, 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, or 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 2013 Shelf was declared effective by the SEC on July 26, 2013.

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 have been issued under the 2008 Plan since 2011, and the Company does not intend to issue any additional shares from the 2008 Plan in the future.

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. The Board of Directors and stockholders of the Company approved an amendment to the 2012 Plan in August 2013 to increase the number of shares of common stock that may be issued under the 2012 Plan by 5,000,000 shares. In addition, the Board of Directors and stockholders of the Company approved an amendment to the 2012 Plan in August 2015 to further increase the number of common stock that may be issued under the 2012 Plan by 6,000,000 shares, bringing the aggregate shares issuable under the 2012 Plan to 17,553,986. The 2012 Plan as amended and restated became effective on August 20, 2015 and terminates ten years after such date.

On August 2, 2013, the Company, entered into an Underwriting Agreement with Lazard Capital Markets LLC, acting as representative of the underwriters named in the Underwriting Agreement 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 (the “2013 Offering”). JMP Securities LLC and Maxim Group LLC each acted as co-managers for the 2013 Offering. The price to the public in the 2013 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 2013 Offering were approximately $43.4 million, after deducting underwriting discounts and commissions and other offering expenses of $3.2 million payable by the Company, including the Underwriters’ exercise of the overallotment option. The transactions contemplated by the Underwriting Agreement closed on August 7, 2013.

In November 2013, the Company entered into an equity distribution agreement with an investment banking firm. Under the terms of the distribution agreement, the Company may offer and sell up to 4,000,000 shares of its common stock, from time to time, through the investment bank in “at the market” offerings, as defined by the SEC, and pursuant to the 2013 Shelf. During the three and six months ended September 30, 2015, the Company issued no shares of common stock in at the market offerings under the distribution agreement. During the three and six months ended September 30, 2014, the Company issued 2,197,768 shares of common stock in at the market offerings under the distribution agreement with net proceeds of $16.1 million. As of September 30, 2015, the Company has issued 2,532,180 shares of common stock in at the market offerings under the distribution agreement, with net proceeds of $19.6 million.

In December 2014, the Company entered into an equity offering sales agreement with another investment banking firm. Under the terms of the sales agreement, the Company may offer and sell shares of its common stock, from time to time, through the investment bank in “at the market” offerings, as defined by the SEC, and pursuant to the 2013 Shelf. During the three and six months ended September 30, 2015, the Company issued no shares of common stock in at the market offerings under the sales agreement. As of September 30, 2015, the Company sold 1,000,000 shares of common stock in at the market offerings under the sales agreement, with net proceeds of approximately $6.2 million.

The Company will limit future sales under the 2013 distribution agreement and the 2014 sales agreement to ensure that it does not exceed the maximum amount available for sale under its 2013 Shelf. Based on its use of the 2013 Shelf through September 30, 2015, the Company cannot sell more than an aggregate of $26,777,785 in shares of common stock under the 2013 distribution agreement and the 2014 sales agreement.

The Company filed a second shelf registration statement on Form S-3 (File No. 333-202382), or the 2015 Shelf, with the SEC on February 27, 2015 authorizing the offer and sale in one or more offerings of up to $190,000,000 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 compromised one or more of the other securities. This shelf was declared effective by the SEC on March 17, 2015.

On June 18, 2015, the Company entered into an Underwriting Agreement with Jefferies LLC and Piper Jaffray & Co., acting as representatives of the underwriters named in the 2015 Underwriting Agreement and as joint book-running managers, relating to the issuance and sale of 9,425,000 shares of the Company’s common stock, par value $0.001 per share (the “2015 Offering”). The price to the public in the 2015 Offering was $4.25 per share, and the Underwriters have agreed to purchase the shares from the Company pursuant to the 2015 Underwriting Agreement at a price of $3.995 per share. Under the terms of the 2015 Underwriting Agreement, the Company granted the Underwriters an option, exercisable for 30 days, to purchase up to an additional 1,413,750 shares. The Company issued 10,838,750 shares of common stock pursuant to the 2015 Underwriting Agreement, including shares issuable upon the exercise of the over-allotment option, with net proceeds of approximately $43.1 million, after deducting underwriting discounts and commissions and expenses payable by the Company. The shares were issued pursuant to the 2015 Shelf.

No warrants were exercised during the three months ended September 30, 2015 and 2014. During the six months ended September 30, 2015 and 2014, the Company issued 30,186 and 110,600 shares of common stock upon exercise of 38,234 and 111,647 warrants, respectively.

Finally, during the three months ended September 30, 2015 and 2014, the Company issued 2,060 and 28,224 shares of common stock upon exercise of 2,060 and 28,224 stock options, respectively. During the six months ended September 30, 2015 and 2014, the Company issued 27,563 and 88,746 shares of common stock upon exercise of 27,563 and 88,746 stock options, respectively.

Restricted stock awards

During the three months ended September 30, 2015 and 2014, there were 100,692 and 103,804 shares of restricted stock, respectively, 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 187,500 and 190,000 restricted stock units, respectively. During the six months ended September 30, 2015 and 2014, there were 102,951 and 106,105 shares of restricted stock, respectively, 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 193,750 and 196,250 restricted stock units, respectively. Upon the return of the common stock, an equal number of 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 from March 31, 2015 through September 30, 2015 is as follows:

	Number of Shares
Unvested at March 31, 2015		258,750
Granted		—
Vested		(193,750	)
Canceled / forfeited		(2,500	)
Unvested at September 30, 2015		62,500

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 $74,000 and $134,000 for the three months ended September 30, 2015 and 2014, respectively, and approximately $177,000 and $267,000 for the six months ended September 30, 2015 and 2014, respectively. Stock-based compensation expense included in research and development was $3,000 and $4,000 for the three months ended September 30, 2015 and 2014, respectively, and $3,000 and $8,000 for the six months ended September 30, 2015 and 2014, respectively. Stock-based compensation expense included in general and administrative expense was $71,000 and $130,000 for the three months ended September 30, 2015 and 2014, respectively and $174,000 and $259,000 for the six months ended September 30, 2015 and 2014, respectively.

As of September 30, 2015, total unrecognized restricted stock-based compensation expense was approximately $41,000, which will be recognized over a weighted average period of 0.44 years.

Stock options

Under the 2012 Plan, 692,092 and 290,054 stock options were issued during the three months ended September 30, 2015 and 2014, respectively, and 2,454,733 and 556,855 stock options were issued during the six months ended September 30, 2015 and 2014, respectively, at various exercise prices. The stock options generally vest (i) on the one year anniversary of the grant date, (2) quarterly over a three year period, or (3) over a four-year period, with 25% vesting on either the one year anniversary of employment or the one year anniversary of the vesting commencement date, and the remainder vesting ratably over the remaining term.

A summary of the Company’s stock option activity for the six months ended September 30, 2015 is as follows:

	Options Outstanding			Weighted- Average Exercise Price		Aggregate Intrinsic Value
Outstanding at March 31, 2015		7,113,548		$	5.21	$	4,969,499
Options granted		2,454,733		$	4.13
Options canceled / forfeited		(198,297	)	$	6.28
Options exercised		(27,563	)	$	2.94	$	64,477
Outstanding at September 30, 2015		9,342,421		$	4.91	$	3,319,866
Vested and Exercisable at September 30, 2015		4,265,334		$	4.21	$	2,715,019

The weighted-average remaining contractual term of options exercisable and outstanding at September 30, 2015 was approximately 7.19 years.

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			Three Months Ended			Six Months Ended			Six Months Ended
	September 30, 2015			September 30, 2014			September 30, 2015			September 30, 2014
Dividend yield		—			—			—			—
Volatility		74.26	%		76.30	%		74.25	%		77.1	%
Risk-free interest rate		1.48	%		1.66	%		1.60	%		1.61	%
Expected life of options	6.00 years			6.00 years			6.00 years			6.00 years
Weighted average grant date fair value	$	1.39		$	5.16		$	2.70		$	5.06

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 $2,098,000 and $1,962,000 for the three months ended September 30, 2015 and 2014, respectively, and $3,775,000 and $3,367,000 for the six months ended September 30, 2015 and 2014, respectively. Expense included in research and development was $277,000 and $281,000 for the three months ended September 30, 2015 and 2014, respectively, and $626,000 and $529,000 for the six months ended September 30, 2015 and 2014, respectively. Expense included in general and administrative was $1,821,000 and $1,681,000 for the three months ended September 30, 2015 and 2014, respectively, and $3,149,000 and $2,838,000 for the six months ended September 30, 2015 and 2014, respectively.

The total unrecognized compensation cost related to unvested stock option grants as of September 30, 2015 was approximately $17,150,000 and the weighted average period over which these grants are expected to vest is 2.79 years.

Warrants

During the three months ended September 30, 2015 and 2014, there were no cashless warrant exercises. During the six months ended September 30, 2015 and 2014, 38,234 and 8,647 warrants, respectively, were exercised through a cashless exercise provision for issuance of 30,186 and 7,600 shares of common stock, respectively. During the three and six months ended September 30, 2014, 0 and 103,000 warrants, respectively, were exercised at prices ranging from $1.00 to $2.21 for total proceeds of $0 and $224,000, respectively. In addition, during the six months ended September 30, 2015, a warrant that was previously expected to be issued to a service provider and had been expensed in prior periods at its approximate value of $130,000, was cancelled, and the amount was reversed against operating expense during the period.

Of the warrants exercised during the six months ended September 30, 2015 and 2014, 38,234 and 8,647, respectively were derivative liabilities and were valued at the settlement date. For the six months ended September 30, 2015 and 2014, respectively, approximately $138,000, and $55,000, of the warrant liability was removed due to the exercise of these warrants. (See Note 2).

During November 2013 the Company entered into an agreement with a consultant for services. In connection with the agreement, the Company issued 75,000 warrants to purchase common stock, at a price of $7.36, with a life of five years, to be earned over a twelve month service period. The fair value of the warrants was estimated to be approximately $404,000, which was recognized as a prepaid asset and has been amortized over the term of the consulting agreement. These warrants were classified as equity instruments because they do not contain any anti-dilution provisions. The Black-Scholes model, using a volatility rate of 96.90% and a risk-free interest rate factor of 0.60%, was used to determine the value. The Company recognized approximately $101,000 and $202,000 during the three and six months ended September 30, 2014, respectively, related to these services. As of December 31, 2014, these warrants were fully expensed.

Additionally, during September 2014, the Company issued 50,000 warrants to a consultant in recognition of services previously provided. These warrants were classified as equity instruments because they do not contain any anti-dilution provisions. As of December 31, 2014, the full amount of the warrants related to these services, approximately $273,000, had been recognized.

During November 2014 the Company entered into an agreement with a consultant for services. In connection with the agreement, the Company issued 145,000 warrants to purchase common stock, at a price of $6.84, with a life of five years, to be earned over a seventeen month service period ending on March 31, 2016. The final number of vested warrant shares will be determined, at the discretion of management, based on management’s judgment of the satisfaction of specific performance metrics prior to the earlier to occur of March 31, 2016 or the termination of the consulting arrangement with the Company. The initial fair value of the warrants was estimated to be approximately $309,000, which is being revalued and amortized over the term of the consulting agreement. These warrants were classified as equity instruments because they do not contain any anti-dilution provisions. The Black-Scholes model, using a volatility rate of 76.78% and a risk-free interest rate factor of 1.37%, was used to determine the value. The Company recognized an expense reduction of approximately $9,000 and expense of approximately $25,000 during the three and six months ended September 30, 2015, respectively, related to these services.

The following table summarizes warrant activity for the six months ended September 30, 2015:

	Warrants			Weighted- Average Exercise Price
Balance at March 31, 2015		1,178,109		$	2.59
Granted		—		$	—
Exercised		(38,234	)	$	1.00
Cancelled		(37,500	)	$	7.36
Balance at September 30, 2015		1,102,375		$	2.49

The warrants outstanding at September 30, 2015 are exercisable at prices between $0.85 and $7.62 per share, and have a weighted average remaining term of approximately 1.89 years.

Common stock reserved for future issuance

Common stock reserved for future issuance consisted of the following at September 30, 2015:

Common stock warrants outstanding			1,102,375
Common stock options outstanding under the 2008 Plan			622,192
Common stock options outstanding and reserved under the 2012 Plan			15,490,660
Total			17,215,227

Preferred stock

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

Commitments and Contingencies

6 Months Ended

Sep. 30, 2015

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

Note 4. Commitments and Contingencies

Operating leases

The Company leases office and laboratory space under a non-cancelable operating lease which was entered into in February 2012 and amended in December 2013 and March 2015, and a non-cancelable operating lease entered into on January 9, 2015, with the future minimum lease payments from the leases included below. The Company records rent expense on a straight-line basis over the life of the leases and records the excess of expense over the amounts paid as deferred rent. In addition, one of the leases provides for certain improvements made for the Company’s benefit to be funded by the landlord. Such costs, totaling approximately $518,000 to date, have been capitalized as fixed assets and included in deferred rent.

Rent expense was approximately $272,000 and $235,000 for the three months ended September 30, 2015 and 2014, respectively, and $549,000 and $470,000 for the six months ended September 30, 2015 and 2014, respectively.

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

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

On March 12, 2015, the Company entered into a Second Amendment to the Original Lease (the “Second Amendment), to adjust the square footage covered by Amended Lease and an additional portion of the building containing approximately 335 rentable square feet (“Second Expansion Premises”). This square footage adjustment was the result of the re-measurement of each suite and the building overall. The net adjustment to overall leased space was an increase of 88 square feet with a corresponding increase in monthly rental payments at the same rate per square foot as the Expansion Premises.

On January 9, 2015, the Company entered into an agreement to lease a second facility consisting of 5,803 rentable square feet of office and lab space located at 6310 Nancy Ridge Drive, San Diego, CA 92121. The term of the lease is 36 months, beginning on February 1, 2015 and ending on January 31, 2018, with monthly rental payments of approximately $12,000 commencing on April 1, 2015. In addition, there are annual rent escalations of 3.0% on each 12-month anniversary of the lease commencement date.

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, 2015, are as follows (in thousands):

Fiscal year ended March 31, 2016	$	577
Fiscal year ended March 31, 2017		1,157
Fiscal year ended March 31, 2018		1,145
Fiscal year ended March 31, 2019		1,041
Fiscal year ended March 31, 2020		1,072
Thereafter		1,572
Total	$	6,564

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. 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. During the period presented, other than as noted below, the Company has not recorded any accrual for loss contingencies associated with such claims or legal proceedings; determined that an unfavorable outcome is probable or reasonably possible; or determined that the amount or range of any possible loss is reasonably estimable. However, the outcome of legal proceedings and claims brought against the Company is subject to significant uncertainty. Therefore, although management considers the likelihood of such an outcome to be remote, if one or more of these legal matters were resolved against the Company in a reporting period, the Company’s consolidated financial statements for that reporting period could be materially adversely affected.

Spencer Trask Matter

In June 2013, the Company filed a declaratory relief action against Spencer Trask Ventures (“STV”) in the Supreme Court of New York (case #652305/2013) following claims by STV that the Company owed STV additional compensation arising from a warrant tender offer the Company completed in December 2012. The Company requested the court to declare that a Warrant Solicitation Agency Agreement (the “WSAA”) the parties had signed in February 2013 was valid and enforceable, and that STV was not entitled to additional compensation on warrants covered by that agreement. In June 2013, STV initiated an arbitration against the Company in which it alleged that the Company had breached the terms of a Placement Agent Agreement (the “PAA”) the parties had signed in connection with the private placement financings the Company completed in February and March 2012. STV claimed it was entitled to additional compensation and damages, including a cash fee and warrants to purchase common stock, as a result of the Company’s warrant tender offer in December 2012 and its warrant redemption in 2013, and damages for breach of confidentiality provisions in relation to the contacting of warrant holders who participated in the warrant tender offer. The Company denied these allegations, and requested the arbitration panel to award the Company attorneys’ fees.

In August, 2015, the parties agreed to globally resolve the pending disputes and voluntarily dismissed their claims with prejudice. In connection with this resolution, the Company made a payment to STV of $150,000. Although it believes STV’s claims are without merit, the Company determined that accepting the settlement offer was in the best interests of the Company and its stockholders because there is no assurance that the arbitrators would award the Company attorneys’ fees, which the Company would continue to incur moving forward in the arbitration, and because the Company’s counsel offered to waive a portion of its legal fees in order to help effect the settlement. The resolution of this matter did not adversely affect the Company’s business, results of operations, liquidity or financial condition.

- 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, 2015
Risks And Uncertainties [Abstract]
Concentrations	Note 5. 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 located in the United States. 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

Recent Accounting Pronouncements	6 Months Ended
Recent Accounting Pronouncements	Sep. 30, 2015
Accounting Changes And Error Corrections [Abstract]
Recent Accounting Pronouncements	Note 6. Recent Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers, or ASU 2014-09, which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The standard will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The new standard was originally effective for public companies for annual reporting periods beginning after December 15, 2016, with no early application permitted. In August 2015, the FASB issued ASU No. 2015-14 that defers by one year the effective date for all entities, with application permitted as of the original effective date. The updated standard becomes effective for us on April 1, 2018, with early adoption permitted as of April 1, 2017. The standard permits the use of either the retrospective or cumulative effect transition method. We are evaluating the effect that ASU 2014-09 will have on our consolidated financial statements and related disclosures. We have not yet selected a transition method nor have we determined the effect of the standard on our ongoing financial reporting. In August 2014, the FASB issued ASU 2014-15, Presentation of Financial Statements—Going Concern—Disclosures of Uncertainties about an entity’s Ability to Continue as a Going Concern (“ASU 2014-15”). ASU 2014-15 provides new guidance related to management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern by incorporating and expanding upon certain principles that are currently in U.S. auditing standards and to provide related footnote disclosures. This new guidance is effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. The requirements of ASU 2014-15 are not expected to have a significant impact on our consolidated financial statements. In July 2015, the FASB issued ASU 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory. The new guidance was issued to more closely align the measurement of inventory in U.S. GAAP with the measurement of inventory in International Financial Reporting Standards. The core principle of this updated guidance is that an entity should measure inventory at the lower of cost or net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The amendments in ASU 2015-11 apply to inventory that is measured using the first-in, first-out or average cost methods. ASU 2015-11 is effective for annual and interim reporting periods ending after December 15, 2016, including interim periods within those fiscal years and should be applied prospectively. Early adoption is permitted as of the beginning of an interim or annual reporting period. The requirements of ASU 2015-11 are not expected to have a significant impact on our consolidated financial statements.

- Definition

The entire disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 270

-SubTopic 10

-Section 45

-Paragraph 13

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-Glossary Accounting Change

-URI http://asc.fasb.org/extlink&oid=6503790

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-Glossary Direct Effects of a Change in Accounting Principle

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-Glossary Indirect Effects of a Change in Accounting Principle

-URI http://asc.fasb.org/extlink&oid=6515603

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-Glossary Change in Accounting Principle

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.10-01.(b)(6))

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-Glossary Retrospective Application

-URI http://asc.fasb.org/extlink&oid=6523989

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+ Details

Subsequent Events	6 Months Ended
Subsequent Events	Sep. 30, 2015
Subsequent Events [Abstract]
Subsequent Events	Note 7. Subsequent Events Severance and Change in Control Plan On November 4, 2015, the Company entered into a Severance and Change in Control Plan Participation Agreement (the “Participation Agreement”) with its executive officers and certain key employees pursuant to the Organovo Holdings, Inc. Severance and Change in Control Plan (the “Severance Plan”) approved by the Compensation Committee of the Board of Directors. The Severance Plan establishes the amount of severance payments and benefits payable to the participant in the event of a (i) termination of the participant’s employment by the Company for reasons other than Cause, death or Disability (each as defined in the Severance Plan) or by the participant for Good Reason (as defined in the Severance Plan) and (ii) termination of the participant’s employment by the Company for reasons other than Cause, death or Disability or by the participant for Good Reason six months before or within 12 months after a Change in Control (as defined in the Severance Plan). The Participant Agreement provides that the terms of the Severance Plan supersede and replace any existing employment and severance agreements between the Company and a participant, and any such agreements are immediately terminated. In addition, the Participation Agreement provides that any equity award agreements held by a participant are amended to provide that the terms “Cause”, “Change of Control”, “Disability” and “Good Reason” as defined in the Severance Plan govern the outstanding equity award agreements.

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

6 Months Ended

Sep. 30, 2015

Accounting Policies [Abstract]

Nature of Operations and Basis of Presentation

Nature of operations and basis of presentation

Liquidity

Use of estimates

Financial 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.

Restricted cash

Inventory

Fixed assets and depreciation

Impairment of long-lived assets

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, 2015 (in thousands):
	Balance at September 30, 2015		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	16		—		—	$	16

	Balance at March 31, 2015		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	126		—		—	$	126

The following table presents the activity for liabilities measured at estimated fair value using unobservable inputs for the six months ended September 30, 2015:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

	Warrant Derivative Liability (in thousands)
Balance at March 31, 2015	$	126
Issuances		—
Adjustments to estimated fair value		28
Warrant liability removal due to settlements		(138	)
Warrant liability reclassified to equity		—
Balance at September 30, 2015	$	16

Research and development

Income taxes

Revenue recognition

Revenue arrangements with multiple deliverables

Product revenue

Revenue from research service agreements

Research and development revenue under collaborative agreements

Grant revenues

Stock-based compensation

Comprehensive income (loss)

Net loss per share

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

6 Months Ended

Sep. 30, 2015

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, 2015 (in thousands):
	Balance at September 30, 2015		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	16		—		—	$	16

	Balance at March 31, 2015		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	126		—		—	$	126

Activity for Liabilities Measured at Estimated Fair Value Using Unobservable Inputs

The following table presents the activity for liabilities measured at estimated fair value using unobservable inputs for the six months ended September 30, 2015:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

	Warrant Derivative Liability (in thousands)
Balance at March 31, 2015	$	126
Issuances		—
Adjustments to estimated fair value		28
Warrant liability removal due to settlements		(138	)
Warrant liability reclassified to equity		—
Balance at September 30, 2015	$	16

- 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, 2015

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Assumptions Used to Value Derivative Liabilities at End of Each Reporting Period

The derivative liabilities were valued at the end of each reporting period using a Monte Carlo valuation model with the following assumptions:

	September 30, 2015			March 31, 2015			September 30, 2014
Closing price per share of common stock	$	2.68		$	3.54		$	6.37
Exercise price per share	$	1.00		$	1.00		$	1.00
Expected volatility		71.60	%		76.80	%		76.50	%
Risk-free interest rate		0.33	%		0.56	%		0.58	%
Dividend yield		—			—			—
Remaining expected term of underlying securities (years)		1.46			1.96			2.46

- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

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

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+ Details

Stockholders' Equity (Tables)

6 Months Ended

Sep. 30, 2015

Equity [Abstract]

Summary of Company's Restricted Stock Award Activity

A summary of the Company’s restricted stock award activity from March 31, 2015 through September 30, 2015 is as follows:

	Number of Shares
Unvested at March 31, 2015		258,750
Granted		—
Vested		(193,750	)
Canceled / forfeited		(2,500	)
Unvested at September 30, 2015		62,500

Summary of Stock Option Activity

A summary of the Company’s stock option activity for the six months ended September 30, 2015 is as follows:

	Options Outstanding			Weighted- Average Exercise Price		Aggregate Intrinsic Value
Outstanding at March 31, 2015		7,113,548		$	5.21	$	4,969,499
Options granted		2,454,733		$	4.13
Options canceled / forfeited		(198,297	)	$	6.28
Options exercised		(27,563	)	$	2.94	$	64,477
Outstanding at September 30, 2015		9,342,421		$	4.91	$	3,319,866
Vested and Exercisable at September 30, 2015		4,265,334		$	4.21	$	2,715,019

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			Three Months Ended			Six Months Ended			Six Months Ended
	September 30, 2015			September 30, 2014			September 30, 2015			September 30, 2014
Dividend yield		—			—			—			—
Volatility		74.26	%		76.30	%		74.25	%		77.1	%
Risk-free interest rate		1.48	%		1.66	%		1.60	%		1.61	%
Expected life of options	6.00 years			6.00 years			6.00 years			6.00 years
Weighted average grant date fair value	$	1.39		$	5.16		$	2.70		$	5.06

Summary of Warrant Activity

The following table summarizes warrant activity for the six months ended September 30, 2015:

	Warrants			Weighted- Average Exercise Price
Balance at March 31, 2015		1,178,109		$	2.59
Granted		—		$	—
Exercised		(38,234	)	$	1.00
Cancelled		(37,500	)	$	7.36
Balance at September 30, 2015		1,102,375		$	2.49

Common Stock Reserved for Future Issuance

Common stock reserved for future issuance consisted of the following at September 30, 2015:

Common stock warrants outstanding			1,102,375
Common stock options outstanding under the 2008 Plan			622,192
Common stock options outstanding and reserved under the 2012 Plan			15,490,660
Total			17,215,227

- 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, 2015

Commitments And Contingencies Disclosure [Abstract]

Future Minimum Rental Payments Required under Operating Leases that have Initial or Remaining Non-Cancelable Lease Terms in Excess of One Year

Future minimum rental payments required under operating leases that have initial or remaining non-cancelable lease terms in excess of one year as of September 30, 2015, are as follows (in thousands):

Fiscal year ended March 31, 2016	$	577
Fiscal year ended March 31, 2017		1,157
Fiscal year ended March 31, 2018		1,145
Fiscal year ended March 31, 2019		1,041
Fiscal year ended March 31, 2020		1,072
Thereafter		1,572
Total	$	6,564

Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended		6 Months Ended			1 Months Ended	3 Months Ended	6 Months Ended		3 Months Ended		6 Months Ended					6 Months Ended	1 Months Ended	6 Months Ended	0 Months Ended
	Jun. 23, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Mar. 31, 2015	Sep. 30, 2014 NIH Research Grants [Member]	Sep. 30, 2015 NIH Research Grants [Member]	Sep. 30, 2015 NIH Research Grants [Member]	Sep. 30, 2014 NIH Research Grants [Member]	Sep. 30, 2015 Private, Not-for-Profit Organization [Member]	Sep. 30, 2014 Private, Not-for-Profit Organization [Member]	Sep. 30, 2015 Private, Not-for-Profit Organization [Member]	Sep. 30, 2014 Private, Not-for-Profit Organization [Member]	Sep. 30, 2015 Research and Development Services [Member]	Mar. 31, 2015 Research and Development Services [Member]	Sep. 30, 2015 Research and Development Services [Member] Up Front Payment Arrangement [Member]	Sep. 30, 2015 Maximum [Member]	Aug. 31, 2013 Maximum [Member] Private, Not-for-Profit Organization [Member]	Sep. 30, 2015 Minimum [Member]	Jun. 23, 2015 2015 Underwriting Agreement [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit		$ (142,043,000)		$ (142,043,000)		$ (122,295,000)
Cash flow from operations				14,921,000	9,677,000
Sale of common stock shares		2,060	28,224																		10,838,750
Gross proceeds from sale of common stock shares	46,100,000
Maturity of highly liquid investment																		90 days
Restricted cash		78,800		78,800		78,800
Inventory		68,000		68,000		66,000
Obsolete inventory reserve		32,000		32,000		31,000
Estimated useful life of the fixed assets				The estimated useful lives of the fixed assets range between three and seven years.
Useful life of fixed assets, range																		7 years		3 years
Impairment of long-lived assets				0
Deferred revenue															1,409,000	259,000	1,000,000
Revenue recognized under grants		95,000	5,000	178,000	35,000			74,000	148,000	0	21,000	5,000	30,000	35,000
Revenue recognized under grants							222,000												251,700
Dilutive effect		$ 0	$ 0	$ 0	$ 0
Common stock equivalents excluded from computing diluted net loss per share		10,500,000	7,900,000	10,500,000	7,900,000

Description of Business and Summary of Significant Accounting Policies - Estimated Fair Values of Liabilities Measured on Recurring Basis (Detail) (Warrants [Member], USD $) In Thousands, unless otherwise specified	Sep. 30, 2015	Mar. 31, 2015
Fair Value, Measurements, Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrant liability	$ 16	$ 126
Quoted Prices in Active Markets (Level 1) [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrant liability	0	0
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrant liability	0	0
Significant Other Unobservable Inputs (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrant liability	16	126
Significant Other Unobservable Inputs (Level 3) [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrant liability	$ 16	$ 126

Description of Business and Summary of Significant Accounting Policies - Activity for Liabilities Measured at Estimated Fair Value Using Unobservable Inputs (Detail) (Significant Other Unobservable Inputs (Level 3) [Member], Warrants [Member], USD $) In Thousands, unless otherwise specified	6 Months Ended
	Sep. 30, 2015
Significant Other Unobservable Inputs (Level 3) [Member] \| Warrants [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Warrant Derivative Liability, Beginning balance	$ 126
Issuances	0
Adjustments to estimated fair value	28
Warrant liability removal due to settlements	(138)
Warrant liability reclassified to equity	0
Warrant Derivative Liability, Ending balance	$ 16

Derivative Liability - Additional Information (Detail) (USD $)	1 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended
	Nov. 30, 2014	Nov. 30, 2013	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2015
Derivative [Line Items]
Warrants maturity term	5 years	5 years					5 years	5 years
Estimated fair value of the outstanding warrant liabilities			$ 16,000		$ 16,000				$ 126,000
Change in fair value of warrant liabilities			9,000	(94,000)	28,000	(64,000)
Exercised derivative liabilities			0	0	38,234	8,647
Warrants [Member]
Derivative [Line Items]
Estimated fair value of the outstanding warrant liabilities									100,000
Warrants [Member] \| Maximum [Member]
Derivative [Line Items]
Estimated fair value of the outstanding warrant liabilities			$ 100,000		$ 100,000

- 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 within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References+ Details

Derivative Liability - Assumptions Used to Value Derivative Liabilities at Closing Dates of Private Placements (Detail) (Warrant Derivative Liability [Member], USD $)	6 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Mar. 31, 2015
Warrant Derivative Liability [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Closing price per share of common stock	$ 2.68	$ 6.37	$ 3.54
Exercise price per share	$ 1.00	$ 1.00	$ 1.00
Expected volatility	71.60%	76.50%	76.80%
Risk-free interest rate	0.33%	0.58%	0.56%
Dividend yield	0.00%	0.00%	0.00%
Remaining expected term of underlying securities (years)	1 year 5 months 16 days	2 years 5 months 16 days	1 year 11 months 16 days

Stockholders' Equity - Additional Information (Detail) (USD $)	0 Months Ended		3 Months Ended		6 Months Ended			3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended			0 Months Ended		1 Months Ended		6 Months Ended		6 Months Ended							0 Months Ended			6 Months Ended
	Jun. 23, 2015	Aug. 02, 2013	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Mar. 31, 2015	Sep. 30, 2015 Research and development expense [Member]	Sep. 30, 2014 Research and development expense [Member]	Sep. 30, 2015 Research and development expense [Member]	Sep. 30, 2014 Research and development expense [Member]	Sep. 30, 2015 General and administrative expense [Member]	Sep. 30, 2014 General and administrative expense [Member]	Sep. 30, 2015 General and administrative expense [Member]	Sep. 30, 2014 General and administrative expense [Member]	Sep. 30, 2015 Restricted stock units (RSUs) [Member]	Sep. 30, 2014 Restricted stock units (RSUs) [Member]	Sep. 30, 2015 Restricted stock units (RSUs) [Member]	Sep. 30, 2014 Restricted stock units (RSUs) [Member]	Sep. 30, 2015 Restricted stock [Member]	Sep. 30, 2014 Restricted stock [Member]	Sep. 30, 2015 Restricted stock [Member]	Sep. 30, 2014 Restricted stock [Member]	Sep. 30, 2015 Equity Distribution Agreement [Member]	Sep. 30, 2014 Equity Distribution Agreement [Member]	Sep. 30, 2015 Equity Distribution Agreement [Member]	Sep. 30, 2014 Equity Distribution Agreement [Member]	Sep. 30, 2015 Equity Offering Sales Agreement [Member]	Jun. 23, 2015 2015 Underwriting Agreement [Member]	Jun. 18, 2015 2015 Underwriting Agreement [Member]	Nov. 30, 2013 Maximum [Member] Equity Distribution Agreement [Member]	Sep. 30, 2015 Maximum [Member] Equity Distribution Agreement [Member]	Sep. 30, 2015 Equity Incentive Plan 2008 [Member]	May 31, 2008 Equity Incentive Plan 2008 [Member]	Sep. 30, 2015 Equity Incentive Plan 2012 [Member]	Aug. 31, 2015 Equity Incentive Plan 2012 [Member]	Aug. 31, 2013 Equity Incentive Plan 2012 [Member]	Jan. 31, 2012 Equity Incentive Plan 2012 [Member]	Feb. 27, 2015 IPO [Member]	Jul. 17, 2013 IPO [Member]	Aug. 02, 2013 Secondary Offering [Member]	Jun. 18, 2015 Secondary Offering [Member] 2015 Underwriting Agreement [Member]	Jun. 18, 2015 Over Allotment Option 2015 Underwriting Agreement [Member]	Aug. 02, 2013 Over Allotment Option Underwriting Agreement [Member]	Sep. 30, 2015 Exercise of Stock Options [Member]	Sep. 30, 2014 Exercise of Stock Options [Member]
Class Of Stock [Line Items]
Securities authorized for offer and sale, amount																																$ 26,777,785							$ 190,000,000	$ 100,000,000
Common shares authorized to be issued																																		1,521,584		6,000,000	5,000,000	6,553,986
Termination date of Equity Incentive Plan																																	Jul. 01, 2018
Shares issued during the year																																	0
Shares available for issuance																																				17,553,986
Termination period of Equity Incentive Plan																																			10 years
Issuance of common stock			92,327,772		92,327,772		81,536,724																	2,532,180	2,197,768	2,532,180	2,197,768	0													10,350,000		9,425,000	1,350,000
Offering price per share		$ 4.50																																							$ 4.23	$ 4.25
Proceeds from issuance of common stock		43,400,000
Underwriting discounts and commissions and other offering expenses		3,200,000
Number of shares to be offered and sold in equity distribution agreement																															4,000,000
Value of shares sold under equity distribution agreement																									16,100,000	19,600,000	16,100,000
Issuance of common stock from stock options exercises, net, Shares			2,060	28,224																				0		0		1,000,000	10,838,750													10,838,750			27,563	88,746
Gross proceeds from sale of common stock shares	46,100,000																											6,200,000														43,100,000
Common stock, par value			$ 0.001		$ 0.001		$ 0.001																																			$ 0.001
Sale of stock price per share net of fees																																											$ 3.995
Stock option exercisable, period																														30 days
Additional common stock issued on exercise of option by underwriters																														1,413,750
Issuance of common stock from warrant exercises, net, Shares					30,186	110,600
Warrants exercised			0	0	38,234	111,647
Stock option exercised			2,060	28,224	27,563	88,746
Restricted stock surrendered																100,692	103,804	102,951	106,105
Restricted stock awards vested during the period																187,500	190,000	193,750	196,250			193,750
Stock option granted with immediate vesting			100,692	103,804	102,951	106,105
Total employee stock-based compensation recorded as operating expenses								3,000	4,000	3,000	8,000	71,000	130,000	174,000	259,000					74,000	134,000	177,000	267,000
Unrecognized restricted stock-based compensation expense																				$ 41,000		$ 41,000
Total unrecognized compensation cost related, weighted average period																						5 months 9 days

Stockholders' Equity - Summary of Company's Restricted Stock Award Activity (Detail) (Restricted stock [Member])	6 Months Ended
	Sep. 30, 2015
Restricted stock [Member]
Class Of Stock [Line Items]
Beginning balance, Unvested, Number of Shares	258,750
Granted, Number of Shares	0
Vested, Number of Shares	(193,750)
Canceled / forfeited, Number of Shares	(2,500)
Ending balance, Unvested, Number of Shares	62,500

Stockholders' Equity - Additional Information 1 (Detail) (USD $)	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Class Of Stock [Line Items]
Issuances of common stock from stock option exercises, Shares	2,060	28,224	27,563	88,746
Weighted-average remaining contractual term of options exercisable			7 years 2 months 9 days
Weighted-average remaining contractual term of options outstanding			7 years 2 months 9 days
Total unrecognized compensation cost related to unvested stock option grants	$ 17,200,000		$ 17,200,000
Research and development expense [Member]
Class Of Stock [Line Items]
Total employee stock-based compensation recorded as operating expenses	3,000	4,000	3,000	8,000
General and administrative expense [Member]
Class Of Stock [Line Items]
Total employee stock-based compensation recorded as operating expenses	71,000	130,000	174,000	259,000
2012 Plan [Member]
Class Of Stock [Line Items]
Issuances of common stock from stock option exercises, Shares	692,092	290,054	2,454,733	556,855
Stock options [Member]
Class Of Stock [Line Items]
Total employee stock-based compensation recorded as operating expenses	2,098,000	1,962,000	3,775,000	3,367,000
Total unrecognized compensation cost related, weighted average period			2 years 9 months 15 days
Stock options [Member] \| Research and development expense [Member]
Class Of Stock [Line Items]
Total employee stock-based compensation recorded as operating expenses	277,000	281,000	626,000	529,000
Stock options [Member] \| General and administrative expense [Member]
Class Of Stock [Line Items]
Total employee stock-based compensation recorded as operating expenses	$ 1,821,000	$ 1,681,000	$ 3,149,000	$ 2,838,000
Stock options [Member] \| 2012 Plan [Member]
Class Of Stock [Line Items]
Award vesting conditions			stock options generally vest (i) on the one year anniversary of the grant date, (2) quarterly over a three year period, or (3) over a four-year period, with 25% vesting on either the one year anniversary of employment or the one year anniversary of the vesting commencement date
Stock options [Member] \| 2012 Plan [Member] \| Yearly Vesting [Member]
Class Of Stock [Line Items]
Award vesting percentage			25.00%

- Definition

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

+ References+ Details

Stockholders' Equity - Summary of Stock Option Activity (Detail) (USD $)	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Options Outstanding, Beginning balance			7,113,548
Granted, Options Outstanding			2,454,733
Canceled / forfeited, Options Outstanding			(198,297)
Exercised, Options Outstanding	(2,060)	(28,224)	(27,563)	(88,746)
Options Outstanding, Ending balance	9,342,421		9,342,421
Vested and Exercisable, Options Outstanding	4,265,334		4,265,334
Weighted-Average Exercise Price, Options Beginning balance			$ 5.21
Options granted, Weighted-Average Exercise Price			$ 4.13
Options canceled / forfeited, Weighted-Average Exercise Price			$ 6.28
Options exercised, Weighted-Average Exercise Price			$ 2.94
Weighted-Average Exercise Price, Options Ending balance	$ 4.91		$ 4.91
Vested and Exercisable, Weighted-Average Exercise Price	$ 4.21		$ 4.21
Aggregate Intrinsic Value, Options Beginning balance			$ 4,969,499
Options Exercised, Aggregate Intrinsic Value			64,477
Aggregate Intrinsic Value, Options Ending balance	3,319,866		3,319,866
Vested and Exercisable at December 30, 2014	$ 2,715,019		$ 2,715,019

Stockholders' Equity - Fair Value of Employee Stock Options (Detail) (USD $)	1 Months Ended		3 Months Ended		6 Months Ended
	Nov. 30, 2014	Nov. 30, 2013	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Dividend yield			0.00%	0.00%	0.00%	0.00%
Volatility	76.78%	96.90%	74.26%	76.30%	74.25%	77.10%
Risk-free interest rate	1.37%	0.60%	1.48%	1.66%	1.60%	1.61%
Expected life of options			6 years	6 years	6 years	6 years
Weighted average grant date fair value			$ 1.39	$ 5.16	$ 2.70	$ 5.06

Stockholders' Equity - Additional Information 2 (Detail) (USD $)	1 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended
	Nov. 30, 2014	Nov. 30, 2013	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Mar. 31, 2012	Mar. 31, 2011
Class Of Stock [Line Items]
Warrant liability reduced					$ 138,000	$ 55,000
Exercised derivative liabilities			0	0	38,234	8,647
Warrants to purchase common stock	145,000	75,000
Warrants maturity term	5 years	5 years					5 years	5 years
Volatility	76.78%	96.90%	74.26%	76.30%	74.25%	77.10%
Risk-free interest rate	1.37%	0.60%	1.48%	1.66%	1.60%	1.61%
Recognized expenses of warrants			101,000		202,000
Warrants earned, service period	17 months	12 months
Warrants issued						50,000
Weighted-average remaining contractual term of options exercisable					7 years 2 months 9 days
Preferred stock, shares authorized			25,000,000		25,000,000
Preferred stock, shares outstanding			0		0
Consultation Service Agreement September 2014
Class Of Stock [Line Items]
Recognized expenses of warrants					273,000
Consultation Service Agreement November 2014
Class Of Stock [Line Items]
Recognized expenses of warrants			9,000		25,000
Minimum [Member]
Class Of Stock [Line Items]
Warrants exercisable price, per share			$ 0.85		$ 0.85
Maximum [Member]
Class Of Stock [Line Items]
Warrants exercisable price, per share			$ 7.62		$ 7.62
Warrants [Member]
Class Of Stock [Line Items]
Number of warrant exercised through cashless			0	0	38,234	8,647
Cashless exercise for issuance of common stock					30,186	7,600
Number Of Warrants Exercised				0		103,000
Warrants exercisable price, per share	$ 6.84	$ 7.36
Warrant liability reduced				0		224,000
Amount reversed against operating expense					130,000
Warrants liability					138,000	55,000
Estimated fair value of warrants	$ 309,000	$ 404,000
Weighted-average remaining contractual term of options exercisable					1 year 10 months 21 days
Warrants [Member] \| Minimum [Member]
Class Of Stock [Line Items]
Warrants exercisable price, per share				$ 1.00		$ 1.00
Warrants [Member] \| Maximum [Member]
Class Of Stock [Line Items]
Warrants exercisable price, per share				$ 2.21		$ 2.21

Stockholders' Equity - Summary of Warrant Activity (Detail) (USD $)	3 Months Ended		6 Months Ended		3 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015 Warrants [Member]	Mar. 31, 2015 Warrants [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options Outstanding, Beginning balance			7,113,548			1,178,109
Granted, Options Outstanding			2,454,733		0
Exercised, Options Outstanding	(2,060)	(28,224)	(27,563)	(88,746)	(38,234)
Cancelled, Options Outstanding					(37,500)
Options Outstanding, Ending balance	9,342,421		9,342,421		1,102,375	1,178,109
Weighted-Average Exercise Price, Options Beginning balance			$ 5.21			$ 2.59
Granted, Weighted-Average Exercise Price			$ 4.13		$ 0
Exercised, Weighted-Average Exercise Price			$ 2.94		$ 1.00
Cancelled, Weighted-Average Exercise Price					$ 7.36
Weighted-Average Exercise Price, Options Ending balance	$ 4.91		$ 4.91		$ 2.49	$ 2.59

- 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, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance	17,215,227
Warrants [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance	1,102,375
Stock options [Member] \| Equity Incentive Plan 2008 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance	622,192
Stock options [Member] \| Equity Incentive Plan 2012 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance	15,490,660

Commitments and Contingencies - Additional Information (Detail) (USD $)	0 Months Ended		3 Months Ended		6 Months Ended		43 Months Ended
	Jan. 09, 2015 sqft	Dec. 05, 2013 sqft	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Jun. 30, 2015	Mar. 12, 2015 sqft	Aug. 31, 2015 STV [Member]
Commitments And Contingencies Disclosure [Line Items]
Leasehold improvements					$ 374,000	$ 47,000	$ 518,000
Rent expense			272,000	235,000	549,000	470,000
Base rent under the lease	12,000	38,800			38,800
Base rent escalators	3.00%	3.00%						3.00%
Lease term with option to extend					48 months
Increased office space size		15,268							335
Area of leased office space	5,803	15,539
Total office space under lease agreement		30,807
Lease expiration date		Aug. 01, 2016
Rent expense per month		38,934
Additional office space		14,500
Expansion premises commencement date					Sep. 01, 2014
Increase of net adjustment leased space									88
Lease term	36 months
Lease rental period start date	Feb. 01, 2015
Lease rental period end date	Jan. 31, 2018
Payment made										$ 150,000

Commitments and Contingencies - Future Minimum Rental Payments Required under Operating Leases that have Initial or Remaining Non-Cancelable Lease Terms in Excess of One Year (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2015
Commitments And Contingencies Disclosure [Abstract]
Fiscal year ended March 31, 2016	$ 577
Fiscal year ended March 31, 2017	1,157
Fiscal year ended March 31, 2018	1,145
Fiscal year ended March 31, 2019	1,041
Fiscal year ended March 31, 2020	1,072
Thereafter	1,572
Total	$ 6,564