Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Mar. 31, 2016	Jun. 01, 2016	Sep. 30, 2015
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Mar. 31, 2016
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	FY
Trading Symbol	ONVO
Entity Registrant Name	ORGANOVO HOLDINGS, INC.
Entity Central Index Key	0001497253
Current Fiscal Year End Date	--03-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		92,391,989
Entity Public Float			$ 227,966,466

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2016	Mar. 31, 2015
Current Assets
Cash and cash equivalents	$ 62,091	$ 50,142
Accounts receivable	259	0
Inventory, net	334	66
Prepaid expenses and other current assets	968	1,054
Total current assets	63,652	51,262
Fixed assets, net	3,711	2,042
Restricted cash	79	79
Other assets, net	134	106
Total assets	67,576	53,489
Current Liabilities
Accounts payable	787	1,387
Accrued expenses	2,450	2,257
Deferred rent	139	759
Deferred revenue	1,110	227
Capital lease obligation	0	5
Warrant liabilities	4	126
Total current liabilities	4,490	4,761
Deferred revenue, net of current portion	0	32
Deferred rent, net of current portion	905	0
Total liabilities	5,395	4,793
Commitments and Contingencies (Note 6)	0	0
Stockholders’ Equity
Common stock, $0.001 par value; 150,000,000 shares authorized, 92,391,989 and 81,536,724 shares issued and outstanding at March 31, 2016 and March 31, 2015, respectively	92	82
Additional paid-in capital	222,959	170,909
Accumulated deficit	(160,870)	(122,295)
Total stockholders’ equity	62,181	48,696
Total Liabilities and Stockholders’ Equity	$ 67,576	$ 53,489

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2016	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	92,391,989	81,536,724
Common stock, shares outstanding	92,391,989	81,536,724

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Revenues
Product and service	$ 806	$ 314	$ 0
Collaborations	486	134	248
Grants	191	123	131
Total Revenues	1,483	571	379
Selling, general, and administrative expenses	22,118	17,947	13,054
Research and development expenses	18,008	12,921	7,974
Loss from Operations	(38,643)	(30,297)	(20,649)
Other Income (Expense)
Change in fair value of warrant liabilities	(17)	196	(5,120)
Loss on disposal of fixed assets	0	(12)	(84)
Interest expense	0	(1)	(13)
Interest income	88	32	18
Total Other Income (Expense)	71	215	(5,199)
Income Tax Expense	(3)	0	0
Net Loss	$ (38,575)	$ (30,082)	$ (25,848)
Net loss per common share—basic and diluted	$ (0.43)	$ (0.38)	$ (0.35)
Weighted average shares used in computing net loss per common share—basic and diluted	90,057,356	79,650,087	73,139,618

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]
Beginning balance at Mar. 31, 2013	$ 8,969	$ 65	$ 75,269	$ (66,365)
Beginning balance, Shares at Mar. 31, 2013		64,687,000
Issuance of common stock from warrant exercises, net	1,101	$ 3	1,098	0
Issuance of common stock from warrant exercises, net, Shares		2,713,000
Issuance of restricted common stock	0	$ 0	0	0
Issuance of restricted common stock, Shares		60,000
Restricted stock forfeitures	0	$ 0	0	0
Restricted stock forfeitures, Shares		(215,000)
Issuance of common stock from public offering, net	46,915	$ 10	46,905	0
Issuance of common stock from public offering, Shares		10,684,000
Stock-based compensation expense	4,600	$ 0	4,600	0
Expense related to modification of warrants	12	0	12	0
Warrant liability removed due to exercises of warrants	10,874	0	10,874	0
Warrant liability reclassified to equity	767	0	767	0
Stock option exercises	402	$ 0	402	0
Stock option exercises, Shares		184,000
Issuance of warrants to consultant	492	$ 0	492	0
Net loss	(25,848)	0	0	(25,848)
Ending balance at Mar. 31, 2014	48,284	$ 78	140,419	(92,213)
Ending balance, Shares at Mar. 31, 2014		78,113,000
Issuance of common stock from warrant exercises, net	$ 445	$ 0	445	0
Issuance of common stock from warrant exercises, net, Shares	210,600	211,000
Restricted stock forfeitures	$ 0	$ 0	0	0
Restricted stock forfeitures, Shares		(190,000)
Issuance of common stock from public offering, net	22,307	$ 4	22,303	0
Issuance of common stock from public offering, Shares		3,198,000
Stock-based compensation expense	7,020	$ 0	7,020	0
Warrant liability removed due to exercises of warrants	55	0	55	0
Stock option exercises	$ 351	$ 0	351	0
Stock option exercises, Shares	205,684	205,000
Issuance of warrants to consultant	$ 316	$ 0	316	0
Net loss	(30,082)	0	0	(30,082)
Ending balance at Mar. 31, 2015	48,696	$ 82	170,909	(122,295)
Ending balance, Shares at Mar. 31, 2015		81,537,000
Issuance of common stock from warrant exercises, net	$ 0	$ 0	0	0
Issuance of common stock from warrant exercises, net, Shares	32,914	32,000
Restricted stock forfeitures	$ 0	$ 0	0	0
Restricted stock forfeitures, Shares		(132,000)
Issuance of common stock from public offering, net	43,137	$ 10	43,127	0
Issuance of common stock from public offering, Shares		10,839,000
Stock-based compensation expense	8,556	$ 0	8,556	0
Warrant liability removed due to exercises of warrants	139	0	139	0
Stock option exercises	$ 320	$ 0	320	0
Stock option exercises, Shares	116,001	116,000
Issuance of warrants to consultant	$ 38	$ 0	38	0
Adjustment related to potential equity bonus issuance	(130)	0	(130)	0
Net loss	(38,575)	0	0	(38,575)
Ending balance at Mar. 31, 2016	$ 62,181	$ 92	$ 222,959	$ (160,870)
Ending balance, Shares at Mar. 31, 2016		92,392,000

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Cash Flows From Operating Activities
Net loss	$ (38,575)	$ (30,082)	$ (25,848)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of warrants issued for services	(92)	557	323
Depreciation and amortization	815	472	387
Loss on disposal of fixed assets	0	12	84
Change in fair value of warrant liabilities	17	(196)	5,120
Expense associated with warrant modification	0	0	12
Stock-based compensation	8,556	7,020	4,600
Increase (decrease) in cash resulting from changes in:
Grants receivable	0	0	101
Accounts receivable	(259)	0	0
Inventory	(268)	(3)	25
Prepaid expenses and other assets	83	(389)	(392)
Accounts payable	(600)	1,061	(315)
Accrued expenses	193	1,435	312
Deferred rent	(89)	270	75
Deferred revenue	851	242	(45)
Net cash used in operating activities	(29,368)	(19,601)	(15,561)
Cash Flows From Investing Activities
Deposits released from restriction	0	0	9
Purchases of fixed assets	(2,114)	(1,517)	(277)
Proceeds from disposals of fixed assets	14	0	0
Purchases of intangible assets	(35)	0	0
Net cash used in investing activities	(2,135)	(1,517)	(268)
Cash Flows From Financing Activities
Proceeds from issuance of common stock and exercise of warrants, net	43,137	22,752	48,016
Proceeds from exercise of stock options	320	351	402
Principal payments on capital lease obligations	(5)	(10)	(10)
Deferred financing costs	0	0	(40)
Net cash provided by financing activities	43,452	23,093	48,368
Net Increase in Cash and Cash Equivalents	11,949	1,975	32,539
Cash and Cash Equivalents at Beginning of Period	50,142	48,167	15,628
Cash and Cash Equivalents at End of Period	62,091	50,142	48,167
Supplemental Disclosure of Cash Flow Information:
Interest	0	0	0
Income Taxes	$ 3	$ 4	$ 0

Consolidated Statements of Cash Flows (Parenthetical) $ in Thousands	12 Months Ended
	Mar. 31, 2014 USD ($) shares
Statement Of Cash Flows [Abstract]
Issued warrants to purchase shares of common stock for consulting services shares \| shares	75,000
Issued warrants to purchase shares of common stock for consulting services	$ 404
Warrant liability reduced	10,874
Warrant reclassified as equity instruments	$ 767

Description of Business and Summary of Significant Accounting Policies

12 Months Ended

Mar. 31, 2016

Accounting Policies [Abstract]

Description of Business and Summary of Significant Accounting Policies

1. Description of Business and Summary of Significant Accounting Policies

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

Nature of operations and basis of presentation

References in these notes to the consolidated financial statements to “Organovo Holdings, Inc.,” “Organovo Holdings,” “we,” “us,” “our,” “the Company” and “our Company” refer to Organovo Holdings, Inc. and its consolidated subsidiaries. Our consolidated financial statements include the accounts of the Company as well as its wholly-owned subsidiaries, with all material intercompany accounts and transactions eliminated in consolidation. In December 2014, we established a wholly-owned subsidiary, Samsara Sciences, Inc., to focus on the acquisition of qualified cells in support of our commercial and research endeavors. In September 2015, we established another wholly-owned subsidiary in the United Kingdom, Organovo U.K., Ltd., for the primary purpose of establishing a sales presence in Europe.

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 on raising capital and building infrastructure. In November 2014, the Company announced the commercial release of its first product, the exVive3D™ Human Liver Tissue for use in toxicology and other preclinical drug testing. As of March 31, 2016, the Company had 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.

NYSE MKT listing

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

Liquidity

As of March 31, 2016, the Company had an accumulated deficit of approximately $160.9 million. The Company also had negative cash flows from operations of approximately $29.4 million during the year ended March 31, 2016.

Through March 31, 2016, the Company has financed its operations primarily through the sale of convertible notes, the private placement of equity securities, the sale of common stock through public offerings, and through revenue derived from grants, collaborative research agreements, and product and research service-based agreements. Based on its current operating plan and available cash resources, the Company believes it has sufficient resources to fund its business for at least the next twelve months.

The Company will need additional capital to further fund the development and commercialization of its human tissues that can be employed in drug discovery and development, biological research, and as therapeutic implants for the treatment of damaged or degenerating tissues and organs. The Company intends to cover its future operating expenses through cash on hand, through revenue derived from research service agreements, product sales, collaborative research agreements, grants, 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 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, inventory, prepaid expenses and other assets, accounts payable, accrued expenses, deferred revenue, and capital lease obligations, the carrying amounts are generally considered to be representative of their respective fair values because of the short-term nature of those instruments.

Cash and cash equivalents

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

Derivative financial instruments

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

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

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

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

Restricted cash

As of March 31, 2016 and 2015, the Company had approximately $79,000 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 at March 31, 2016 consists of approximately $206,000 in raw materials, approximately $15,000 in work-in-process inventory, and approximately $113,000 in finished goods. Inventory at March 31, 2015 consisted of approximately $66,000 in raw materials, net of reserves.

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 one 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 occurred as of March 31, 2016.

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 4). The Company’s derivative liabilities are adjusted to reflect estimated fair value at each period end, with any decrease or increase in the estimated fair value being recorded in other income or expense accordingly, as adjustments to the fair value of derivative liabilities. Various factors are considered in the pricing models we use to value the warrants, including the Company’s current stock price, the remaining life of the warrants, the volatility of the Company’s stock price, and the risk free interest rate. Future changes in these factors 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 March 31, 2016 and 2015 (in thousands):
	Balance at March 31, 2016		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	4	$	—	$	—	$	4

	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 years ended March 31, 2016 and 2015:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

	Warrant Derivative Liability (in thousands)
Balance at March 31, 2014	$	377
Issuances	$	—
Adjustments to estimated fair value	$	(196	)
Warrant liability removal due to settlements	$	(55	)
Balance at March 31, 2015	$	126
Issuances	$	—
Adjustments to estimated fair value	$	17
Warrant liability removal due to settlements	$	(139	)
Balance at March 31, 2016	$	4

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 March 31, 2016 and 2015, the Company had approximately $1,110,000 and $259,000, respectively, in deferred revenue related to its commercial products and research service agreements, grants, and collaborative research programs.

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.

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.

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).

In 2011, the Company entered into a research collaboration agreement with a third party to perform research and development services. The agreement, as amended in 2012, was for a total fixed fee of $1,405,000. The Company completed its obligations under this agreement and recognized the remaining revenue of approximately $184,000 during the year ended March 31, 2014, in recognition of the proportional performance achieved.

In September 2013, the Company entered into a research contract agreement with a third party to perform research and development services for fixed fees. The Company completed its obligations under this agreement during the year ended March 31, 2015. The Company recorded approximately $69,000 and $7,000 for the years ended March 31, 2015 and 2014, respectively, in revenue related to the research contract in recognition of the proportional performance achieved.

In October 2013, the Company entered into a research contract agreement with a third party to perform research and development services for fixed fees. The Company completed its obligations under this agreement during the year ended March 31, 2015. The Company recorded approximately $41,000 and $52,000 for the years ended March 31, 2015 and 2014, respectively, in revenue related to the research contract in recognition of the proportional performance achieved.

In November 2014, the Company entered into a collaborative nonexclusive research affiliation with a university medical school and a non-profit medical charity, under which the Company received a one-time grant from the charity towards the placement of a NovoGen Bioprinter at the university for the purpose of developing bioprinted tissues for surgical transplantation research. The Company has recorded approximately $50,000 and $18,000 for the years ended March 31, 2016 and 2015, respectively, in revenue related to this collaboration in recognition of the proportional performance achieved.

In April 2015, the Company entered into a research collaboration agreement with a third party to develop custom tissue models for fixed fees. Based on the proportional performance achieved under this agreement for the year ended March 31, 2016, the Company has recorded approximately $352,000 in collaboration revenue for the year.

Also in April 2015, the Company entered into a multi-year research agreement with a third party to develop multiple custom tissue models for use in drug development. Approximately $80,000 under this agreement was recognized as revenue in recognition of the proportional performance achieved during the year ended March 31, 2016.

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. That 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.

Grant revenues

During August of 2013, the Company was awarded a research grant by a private, not-for-profit organization for up to $251,700, contingent on go/no-go decisions made by the grantor at the completion of each stage of research as outlined in the grant award. Revenues from the grant are based upon internal costs incurred that are specifically covered by the grant, plus an additional rate that provides funding for overhead expenses. Revenue is recognized when the Company incurs expenses that are related to the grant. Revenue recognized under this grant was approximately $43,000, $49,000 and $119,000 for the years ended March 31, 2016, 2015 and 2014, respectively.

During September of 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 those milestones. Revenue recognized under this grant was approximately $148,000 and $74,000 for the years ended March 31, 2016 and 2015, respectively.

Stock-based compensation

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

The Company accounts for equity instruments, including restricted stock or stock options, issued to non-employees in accordance with authoritative guidance for equity based payments to non-employees. Stock options issued to non-employees are accounted for at their estimated fair value determined using the Black-Scholes option-pricing model. The fair value of options granted to non-employees is re-measured as they vest, and the resulting increase in value, if any, is recognized as expense during the period the related services are rendered. Restricted stock issued to non-employees is accounted for at 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 years ended March 31, 2016, 2015 and 2014, the comprehensive loss was equal to the net loss.

Net loss per share

Basic and diluted net loss per share has been computed using the weighted-average number of shares of common stock outstanding during the period. The weighted-average number of shares used to compute diluted loss per share excludes any assumed exercise of stock options and 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 years ended March 31, 2016, 2015 and 2014 as the Company reported a net loss for each respective period and the effect would have been anti-dilutive. Total common stock equivalents that were excluded from computing diluted net loss per share were approximately 10.7 million, 8.6 million, and 7.7 million for the years ended March 31, 2016, 2015 and 2014, respectively.

Fixed Assets

12 Months Ended

Mar. 31, 2016

Property Plant And Equipment [Abstract]

Fixed Assets

2. Fixed Assets

Fixed assets consisted of the following (in thousands):

	March 31, 2016			March 31, 2015
Laboratory equipment	$	2,799		$	1,951
Construction in process		52			529
Computer software and equipment		488			274
Furniture and fixtures		337			135
Leasehold improvements		1,832			155
Vehicles		9			—
		5,517			3,044
Less accumulated depreciation and amortization		(1,806	)		(1,002	)
	$	3,711		$	2,042

Depreciation and amortization expense for the years end March 31, 2016, 2015 and 2014 was approximately $805,000, $464,000, and $380,000, respectively.

Accrued Expenses

12 Months Ended

Mar. 31, 2016

Payables And Accruals [Abstract]

Accrued Expenses

3. Accrued Expenses

Accrued expenses consisted of the following (in thousands):

	March 31, 2016		March 31, 2015
Accrued compensation	$	2,221	$	1,917
Accrued legal and professional fees		168		195
Other accrued expenses		61		145
	$	2,450	$	2,257

Derivative Liability

12 Months Ended

Mar. 31, 2016

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Derivative Liability

4. Derivative Liability

During 2011 and 2012, the Company issued 22,847,182 five-year warrants to purchase the Company’s common stock in connection with financing transactions. The exercise price of the warrants is protected against down-round financing throughout the term of the warrants, as described below. 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 revalued the warrants as of the end of each reporting period, and the estimated fair value of the outstanding warrant liabilities was $4,000 and $126,000 as of March 31, 2016 and 2015, respectively. The change in fair value of the derivative liabilities for the year ended March 31, 2016 was an increase of $17,000. The changes in fair value of the derivative liabilities for the year ended March 31, 2015 and 2014 were a decrease of $196,000 and an increase of $5,120,000, respectively. These changes are included in other income (expense) in the statements of operations.

During the years ended March 31, 2016 and 2015, 43,796 and 8,647 warrants that were classified as derivative liabilities were exercised. The warrants were revalued as of the settlement date, and the change in fair value was recognized to earnings. In addition, in the year ended March 31, 2014, the Company entered into amendment agreements with certain of the warrant holders, which removed the down-round pricing protection provision, resulting in 269,657 of these warrants being reclassified from liability instruments to equity instruments. The Company also recognized a reduction in the warrant liability based on the fair value as of the settlement date for the warrants exercised and as of the modification date for the warrants that were amended, with a corresponding increase in additional paid-in capital.

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

	March 31, 2016			March 31, 2015
Closing price per share of common stock	$	2.17		$	3.54
Exercise price per share	$	1.00		$	1.00
Expected volatility		73.35	%		76.80	%
Risk-free interest rate		0.59	%		0.56	%
Dividend yield		—			—
Remaining expected term of underlying securities (years)		0.96			1.96

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

Upon each adjustment of the exercise price pursuant to the provisions stated above, the number of warrant shares issuable upon exercise of the warrants shall be adjusted by multiplying a number equal to the exercise price in effect immediately prior to such adjustment by the number of warrant shares issuable upon exercise of the warrant immediately prior to such adjustment and dividing the product so obtained by the adjusted exercise price.

- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6441202&loc=d3e80720-113993

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41620-113959

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624163-113959

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5579240-113959

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624177-113959

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80784-113994

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41641-113959

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5579245-113959

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624258-113959

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5708775-113959

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4J
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5708773-113959

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5580258-113959

Reference 16: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4E
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624181-113959

Reference 17: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

Reference 18: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41638-113959

Reference 19: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(n))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Stockholders' Equity

12 Months Ended

Mar. 31, 2016

Equity [Abstract]

Stockholders' Equity

5. Stockholders’ Equity

Common stock

In May of 2008, the Board of Directors of the Company approved the 2008 Equity Incentive Plan (the “2008 Plan”). The 2008 Plan authorized the issuance of up to 1,521,584 common shares for awards of incentive stock options, non-statutory stock options, restricted stock awards, restricted stock award units, and stock appreciation rights. The 2008 Plan terminates on July 1, 2018. No shares 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 shares 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. As of March 31, 2016, 6,486,736 shares remain available for issuance under the 2012 plan.

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.

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 years ended March 31, 2016, 2015 and 2014, the Company issued 0, 2,197,768 and 334,412 shares of common stock in at-the-market offerings under the distribution agreement with net proceeds of $0, $16.1 million and $3.5 million, respectively.

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 Company’s 2013 Shelf. During the years ended March 31, 2016 and 2015, the Company issued 0 and 1,000,000 shares of common stock in at-the-market offerings under the sales agreement with net proceeds of $0 and $6.2 million, respectively. The Company intends to use the net proceeds raised through any at-the-market sales for general corporate purposes, including research and development, the commercialization of the Company’s products, general administrative expenses, and working capital and capital expenditures.

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 effective shelf registration statement previously filed with the SEC. Based on its use of the shelf registration statement through March 31, 2016, 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.

A shelf registration statement on Form S-3 (File No. 333-202382), or the 2015 shelf, was filed 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 comprised of one or more of the other securities. The 2015 shelf was declared effective by the SEC on March 17, 2015.

In addition, during the years ended March 31, 2016 and 2015, the Company issued 32,914 and 210,600 shares of common stock upon exercise of 43,796 and 211,647 warrants, respectively.

During the years ended March 31, 2016 and 2015, the Company issued 116,001 and 205,033 shares of common stock upon exercise of 116,001 and 205,684 stock options, respectively.

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.

Restricted stock awards

On August 6, 2012, 200,000 restricted stock awards were issued to a member of senior management, the vesting of which was performance based with achievement to be measured at December 31, 2014 or earlier if the metric was achieved. As of December 31, 2014, the Company had determined that three of the four target metrics had been achieved with the fourth performance metric criterion not met resulting in 150,000 shares of restricted stock vested and the remaining 50,000 restricted stock awards surrendered back to the Company unvested. The Company recognized the related stock-based compensation expense over the requisite service period ending on March 31, 2015.

During the year ended December 31, 2012, the Company issued an aggregate 950,000 of restricted stock awards to certain members of senior management and 130,000 restricted stock awards to non-executive employees. The vesting schedule is 25% on each anniversary of the vesting start date over four years. Additionally, the Company issued 100,000 restricted stock awards to a consultant. The vesting schedule is 100% after six months.

During the year ended March 31, 2014, 218,655 restricted stock awards were surrendered related to shares of common stock returned to the Company, at the option of the holder, to cover the tax liability related to the vesting of 405,000 restricted stock awards. Upon the return of the common stock, 218,655 stock option grants with immediate vesting were granted to the individual at the vesting date market value strike price.

During the year ended March 31, 2014, the Company issued an aggregate of 60,000 restricted stock units with immediate vesting to a consultant.

During the year ended March 31, 2015, 137,816 restricted stock awards were surrendered related to shares of common stock returned to the Company, at the option of the holder, to cover the tax liability related to the vesting of 255,000 restricted stock awards. Upon the return of the common stock, 137,816 stock option grants with immediate vesting were granted to the individual at the vesting date market value strike price.

During the year ended March 31, 2016, 129,900 restricted stock awards were surrendered related to shares of common stock returned to the Company, at the option of the holder, to cover the tax liability related to the vesting of 250,000 restricted stock awards. Upon the return of the common stock, 129,900 stock option grants with immediate vesting were granted to the individual at the vesting date market value strike price.

During the year ended March 31, 2016, there were 2,500 restricted stock awards forfeited by one employee upon termination of their employment with the Company.

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

	Number of Shares
Unvested at March 31, 2013		985,742
Granted		60,000
Vested		(472,247	)
Canceled / forfeited		—
Unvested at March 31, 2014		573,495
Granted		—
Vested		(262,245	)
Canceled / forfeited		(52,500	)
Unvested at March 31, 2015		258,750
Granted		—
Vested		(250,000	)
Canceled / forfeited		(2,500	)
Unvested at March 31, 2016		6,250

The fair value of each restricted 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 $215,000, $421,000, and $817,000, during the years ended March 31, 2016, 2015 and 2014, respectively. Expense for each of the periods included approximately $5,000, $15,000, and $16,000, for research and development during the years ended March 31, 2016, 2015 and 2014, respectively. General and administrative expense for the years ended March 31, 2016, 2015 and 2014 were approximately $210,000, $406,000, and $801,000, respectively.

As of March 31, 2016, total unrecognized restricted stock-based compensation expense was approximately $3,000, which will be recognized over a weighted average period of 0.25 years.

Stock options

During the years ended March 31, 2016 and 2015, under the 2012 Equity Incentive Plan, 2,966,778 and 1,429,191 incentive stock options were issued, respectively, at various exercise prices. The stock options generally vest on the one year anniversary of the grant date, quarterly over a three year period, or over a four-year period, with a quarter 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 36 month terms with the exception of 129,900 and 139,316 of the incentive stock option grants during the years ended March 31, 2016 and 2015, respectively, that have immediate vesting at the grant date, 0 and 56,500 of the incentive stock option grants in the years ended March 31, 2016 and 2015, respectively, that vest quarterly over three years, and 185,000 and 128,500 of the incentive stock option grants in the years ended March 31, 2016 and 2015, respectively, that vest after one full year.

The following table summarizes stock option activity for the years ended March 31, 2016 and 2015:

	Options Outstanding			Weighted- Average Exercise Price		Aggregate Intrinsic Value
Outstanding at March 31, 2014		5,935,888		$	4.87	$	20,482,823
Options granted		1,429,191		$	6.18
Options canceled		(45,847	)	$	7.17
Options exercised		(205,684	)	$	1.73	$	883,795
Outstanding at March 31, 2015		7,113,548		$	5.21	$	4,969,499
Options granted		2,966,778		$	3.87
Options canceled		(349,698	)	$	6.30
Options exercised		(116,001	)	$	2.76	$	112,441
Outstanding at March 31, 2016		9,614,627		$	4.79	$	1,927,137
Vested and Exercisable at March 31, 2016		5,165,836		$	4.45	$	1,860,789

The weighted-average remaining contractual term of options exercisable and outstanding at March 31, 2016 was approximately 6.16 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:

	Year Ended March 31, 2016			Year Ended March 31, 2015
Dividend yield		—			—
Volatility		73.96	%		76.90	%
Risk-free interest rate		1.57	%		1.60	%
Expected life of options	6.00 years			6.00 years
Weighted average grant date fair value	$	2.52		$	4.14

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 $8,341,000, $6,599,000, and $3,783,000 for the years ended March 31, 2016, 2015 and 2014, respectively. Research and development expense for the years ended March 31, 2016, 2015 and 2014 were approximately $1,243,000, $1,175,000, and $462,000, respectively. General and administrative expense for the years ended March 31, 2016, 2015 and 2014 were approximately $7,098,000, $5,424,000, $3,321,000, respectively.

Included in total stock option-based compensation for the year ended March 31, 2016 is additional expense resulting from acceleration of the vesting schedule to fully vest options held by a terminated executive as pursuant to the 2012 Equity Incentive Plan. Additionally, as part of the severance agreement, a modification was made to extend the exercise period of the fully vested options, resulting in an incremental expense.

The total unrecognized compensation cost related to unvested stock option grants as of March 31, 2016 was approximately $13,385,000 and the weighted average period over which these grants are expected to vest is 2.48 years.

Warrants

During the years ended December 31, 2012 and 2011, the Company issued warrants to investors to purchase 21,347,182 and 2,909,750 shares, respectively, of its common stock.

During the years ended March 31, 2016, 2015 and 2014, 0, 203,000 and 225,000 of these warrants were exercised for cash proceeds of approximately $0, $445,000 and $210,000, respectively, and 43,796, 8,647 and 2,628,003 of these warrants were exercised through a cashless exercise for issuance of 32,914, 7,600 and 2,139,577 shares of common stock, respectively.

During the year ended March 31, 2014, derivative liability warrants of 1,920,874 were exercised.

During the year ended March 31, 2014, the Company entered into amendment agreements for 269,657 warrants to purchase common stock which reduced the exercise price of the warrants from $1.00 to $0.85, which removed the down-round price protection provision of the warrant agreement related to the adjustment of exercise price upon issuance of additional shares of common stock. As a result of the removal of the down-round price protection provision, the warrants were reclassified from liability to equity instruments at their fair value. The Company determined the incremental expense associated with the modification based on the fair value of the awards prior to and subsequent to the modification. The fair value of the awards subsequent to modification was calculated using the Black-Scholes model. The incremental expense associated with the modification of approximately $12,000 was recognized as interest expense for the year ended March 31, 2014.

In 2012 the Company issued a total of 650,000 warrants to purchase common stock, in connection with consulting agreements, at prices ranging from $1.70 to $3.24, with lives ranging from two to five years, to be earned over service periods of up to six months. During the years ended March 31, 2016 and 2015, no warrants held by consultants were exercised. During the year ended March 31, 2014, 348,630 warrants held by consultants were exercised resulting in proceeds to the Company of approximately $891,000. As of March 31, 2016, 1,370 of these warrants are outstanding.

During November 2013, the Company entered into an agreement with a consultant for services. In connection with the agreement, the Company issued 75,000 warrants to purchase common stock, at a price of $7.36, with a life of five years, to be earned over a twelve month service period. The fair value of the warrants was estimated to be approximately $404,000, which was recognized as a prepaid asset and is being amortized over the term of the consulting agreement. These warrants were classified as equity instruments because they do not contain any anti-dilution provisions. The Black-Scholes model, using a volatility rate of 96.90% and a risk-free interest rate factor of 0.60%, was used to determine the value. The Company recognized approximately $0 and $43,000 during the years ended March 31, 2016 and 2015, 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 $237,000 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 was 95,000, based on management’s judgment of the satisfaction of specific performance metrics. The fair value of the warrants was estimated to be approximately $74,000, which was 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 73.4% and a risk-free interest rate factor of 1.21%, was used to determine the value as of March 31, 2016. The Company recognized approximately $41,000 and $36,000 during the years ended March 31, 2016 and 2015, respectively, related to these services. As of March 31, 2016, these warrants were fully expensed.

The following table summarizes warrant activity for the years ended March 31, 2016 and 2015:

	Warrants			Weighted-Average Exercise Price
Balance at March 31, 2014		1,194,756		$	1.79
Granted		195,000		$	7.04
Expired / Canceled		—			—
Exercised		(211,647	)	$	2.14
Balance at March 31, 2015		1,178,109		$	2.59
Granted		—			—
Expired / Canceled		(87,500	)	$	7.06
Exercised		(43,796	)	$	1.00
Balance at March 31, 2016		1,046,813		$	2.29

The warrants outstanding at March 31, 2016 are immediately exercisable at prices between $0.85 and $7.62 per share, and have a weighted average remaining term of approximately 1.28 years.

Common stock reserved for future issuance

Common stock reserved for future issuance consisted of the following at March 31, 2016:

Common stock warrants outstanding			1,046,813
Common stock options outstanding under the 2008 Plan			622,192
Common stock options outstanding and reserved under the 2012 Plan			15,479,171
Total			17,148,176

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

12 Months Ended

Mar. 31, 2016

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

6. Commitments and Contingencies

Operating leases

The Company leases laboratory and office space in San Diego, California under three non-cancelable leases as described below.

Since July 2012, the Company has leased its main facility at 6275 Nancy Ridge Drive, San Diego, CA 92121. The lease, as amended in 2013 and 2015, consists of approximately 30,895 rentable square feet containing laboratory, clean room and office space. Monthly rental payments are currently approximately $83,000 per month with 3% annual escalators. The lease term expires September 1, 2021 with the option to terminate on or after September 1, 2019. The Company also has a right of first refusal on adjacent additional premises of approximately 14,500 square feet.

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% on each 12-month anniversary of the lease commencement date.

On December 28, 2015, the Company entered into an agreement to lease a third facility consisting of 12,088 rentable square feet of office space located at 6166 Nancy Ridge Drive, San Diego, CA 92121. The term of the lease is 12 months, beginning on February 1, 2016 and ending on January 31, 2017, with monthly rental payments of $15,000 commencing on February 1, 2016.

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 $1,088,000, $968,000, and $561,500 for the years ended March 31, 2016, 2015 and 2014, respectively.

Future minimum rental payments required under operating leases that have initial or remaining non-cancelable lease terms in excess of one year as of March 31, 2016, are as follows (in thousands):

Fiscal year ended March 31, 2017	$	1,313
Fiscal year ended March 31, 2018		1,148
Fiscal year ended March 31, 2019		1,044
Fiscal year ended March 31, 2020		1,072
Fiscal year ended March 31, 2021		1,104
Thereafter		467
Total	$	6,148

Legal matters

In addition to commitments and obligations in the ordinary course of business, the Company may be subject, from time to time, 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, 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.

Licensing Agreements and Research Contracts

12 Months Ended

Mar. 31, 2016

Goodwill And Intangible Assets Disclosure [Abstract]

Licensing Agreements and Research Contracts

7. Licensing Agreements and Research Contracts

University of Missouri

In March 2009, the Company entered into a license agreement with the Curators of the University of Missouri to in-license certain technology and intellectual property relating to self-assembling cell aggregates and to intermediate cellular units. The Company received the exclusive worldwide rights to commercialize products comprising this technology for all fields of use. The Company is required to pay the University of Missouri royalties ranging from 1% to 3% of net sales of covered tissue products, and of the fair market value of covered tissues transferred internally for use in the Company’s commercial service business, depending on the level of net sales achieved by the Company each year. A minimum annual royalty of $25,000 is due beginning in calendar 2017 and will be credited against royalties due during the subsequent twelve months. The license agreement terminates upon expiration of the patents licensed and is subject to certain conditions as defined in the license agreement, which are expected to expire after 2029.

In March 2010, the Company entered into a license agreement with the Curators of the University of Missouri to in-license certain technology and intellectual property relating to engineered biological nerve grafts. The Company received the exclusive worldwide rights to commercialize products comprising this technology for all fields of use. The Company is required to pay the University of Missouri royalties ranging from 1% to 3% of net sales of covered tissue products depending on the level of net sales achieved by the Company each year. The license agreement terminates upon expiration of the patents licensed and is subject to certain conditions as defined in the license agreement.

Clemson University

In May 2011, the Company entered into a license agreement with Clemson University Research Foundation to in-license certain technology and intellectual property relating to ink-jet printing of viable cells. The Company received the exclusive worldwide rights to commercialize products comprising this technology for all fields of use. The Company is required to pay the University royalties ranging from 1.5% to 3% of net sales of covered tissue products and the fair market value of covered tissues transferred internally for use in the Company’s commercial service business, depending on the level of net sales reached each year. The license agreement terminates upon expiration of the patents licensed, which is expected to expire in May 2024, and is subject to certain conditions as defined in the license agreement. Minimum annual royalty payments of $20,000 were due for each of the two years beginning with calendar 2014, and $40,000 per year beginning with calendar 2016. The annual minimum royalty is creditable against royalties owed during the same calendar year.

Capitalized license fees consisted of the following (in thousands):

	March 31, 2016			March 31, 2015
License fees	$	148		$	114
Less accumulated amortization		(43	)		(34	)
License fees, net	$	105		$	80

The above license fees, net of accumulated amortization, are included in Other Assets in the accompanying balance sheets and are being amortized over the life of the related patents. Amortization expense of licenses was approximately $9,700, $8,500, and $8,500 for the years ended March 31, 2016, 2015 and 2014, respectively. At March 31, 2016, the weighted average remaining amortization period for all licenses was approximately 11 years. The annual amortization expense of licenses for the next five years is estimated to be approximately $10,300 per year.

Income Taxes

12 Months Ended

Mar. 31, 2016

Income Tax Disclosure [Abstract]

Income Taxes

8. Income Taxes

Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Significant components of the Company’s net deferred tax assets are as follows as of March 31, 2016 and 2015 (in thousands):

	March 31, 2016			March 31, 2015
Deferred tax assets:
Net operating loss carry forwards	$	—		$	—
Research and development credits		—			—
Depreciation and amortization		(105	)		(48	)
Accrued expenses and reserves		862			826
Stock compensation		5,584			3,462
Other, net		12			6
Total deferred tax assets		6,353			4,246
Valuation allowance		(6,353	)		(4,246	)
	$	—		$	—

A full valuation allowance has been established to offset the deferred tax assets as management cannot conclude that realization of such assets is more likely than not. Under the Internal Revenue Code (“IRC”) Sections 382 and 383, annual use of our net operating loss and research tax credit carryforwards to offset taxable income may be limited based on cumulative changes in ownership. We have not completed an analysis to determine whether any such limitations have been triggered as of March 31, 2016. Until this analysis is completed, we have removed the deferred tax assets related to net operating losses and research credits from our deferred tax asset schedule. Further, until a study is completed and any limitation known, no amounts are being considered as an uncertain tax position or disclosed as an unrecognized tax benefit. Due to the existence of the valuation allowance, future changes in the Company’s unrecognized tax benefits will not impact its effective tax rate. Any carryforwards that will expire prior to utilization as a result of such limitations will be removed from deferred tax assets with a corresponding reduction of the valuation allowance. The valuation allowance increased by approximately $2,107,000 and $2,002,000 for the years ended March 31, 2016 and 2015, respectively.

The Company had federal and state net operating loss carryforwards of approximately $89,814,000 and $89,063,000 at March 31, 2016, respectively. The federal and state net operating loss carryforwards will begin expiring in 2028, unless previously utilized. The net operating loss carryforwards included approximately $6,332,000 of windfall tax benefits related to stock compensation that will be recorded as an increase to additional paid in capital if and when realized.

The Company had federal and state research tax credit carryforwards of approximately $1,351,000 and $1,578,000 at March 31, 2016, respectively. The federal research tax credit carryforwards begin expiring in 2028. The state research tax credit carryforwards do not expire.

In 2009 the Company adopted the accounting guidance for uncertainty in income taxes pursuant to ASC 740-10. The adoption of this guidance did not have a material impact on the Company’s consolidated financial statements. The Company did not record any accruals for income tax accounting uncertainties for the year ended March 31, 2016.

The Company’s policy is to recognize interest and penalties that would be assessed in relation to the settlement value of unrecognized tax benefits as a component of income tax expense. The Company did not accrue either interest or penalties from inception through March 31, 2016.

The Company does not have any unrecognized tax benefits that will significantly decrease or increase within 12 months of March 31, 2016.

The Company is subject to tax in the United States and in various state jurisdictions. As of March 31, 2016, the Company’s tax years from inception are subject to examination by the tax authorities. The Company is not currently under examination by any U.S. federal or state jurisdictions.

Concentrations	12 Months Ended
Concentrations	Mar. 31, 2016
Risks And Uncertainties [Abstract]
Concentrations	9. Concentrations Credit risk and significant customers Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of temporary cash investments. The Company maintains cash balances at various financial institutions primarily located within 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. The Company is also potentially subject to concentrations of credit risk in its revenues and accounts receivable. Because it is in the early commercial stage, the Company’s revenues to date have been derived from a relatively small number of customers and collaborators. However, the Company has not historically experienced any accounts receivable write-downs and management does not believe significant credit risk exists as of March 31, 2016.

Recent Accounting Pronouncements	12 Months Ended
Recent Accounting Pronouncements	Mar. 31, 2016
Accounting Changes And Error Corrections [Abstract]
Recent Accounting Pronouncements	11. Recent Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers, 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 these updates 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 these standards on our ongoing financial reporting. In February 2016, the FASB issued ASU 2016-02, Leases, which requires an entity to recognize lease assets and lease liabilities on the balance sheet for leases with terms of more than 12 months and to disclose key information about leasing arrangements. This new guidance is effective for us on April 1, 2019, with early adoption permitted in any interim or annual period. The Company is currently evaluating the impact that this guidance will have on its financial statements and related disclosures. In November 2015, the FASB issued an ASU 2015-17, which requires noncurrent classification of all deferred tax assets and liabilities for annual periods beginning after December 31, 2016, with early adoption permitted. The Company has elected to early adopt this update for the year ended March 31, 2017. The Company will apply this standard on a prospective basis. The effect of this update is not expected to be material to our 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
-Glossary Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6507316

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Direct Effects of a Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6510796

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=56949863&loc=d3e22583-107794

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Indirect Effects of a Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6515603

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=56949863&loc=d3e22580-107794

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.10-01.(b)(6))
-URI http://asc.fasb.org/extlink&oid=27015980&loc=d3e46468-122699

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Accounting Change
-URI http://asc.fasb.org/extlink&oid=6503790

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=56949863&loc=d3e22499-107794

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Retrospective Application
-URI http://asc.fasb.org/extlink&oid=6523989

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=51655806&loc=d3e765-108305

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=51655806&loc=d3e725-108305

+ Details

Quarterly Financial Data (unaudited)

12 Months Ended

Mar. 31, 2016

Quarterly Financial Information Disclosure [Abstract]

Quarterly Financial Data (unaudited)

12. Quarterly Financial Data (unaudited)

The following quarterly financial data, in the opinion of management, fairly presents the results for the periods presented (in thousands, except per share data):

	Year Ended March 31, 2016
	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
Revenue	$	306		$	301		$	328		$	548
Net loss		(8,491	)		(11,257	)		(10,455	)		(8,372	)
Net loss per common share - basic and diluted		(0.10	)		(0.12	)		(0.11	)		(0.09	)
Weighted average shares used in computing net loss per common share—basic and diluted		82,993,966			92,385,150			92,396,358			92,402,668


	Year Ended March 31, 2015
	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
Revenue	$	99		$	50		$	155		$	267
Net loss		(6,433	)		(8,858	)		(6,993	)		(7,798	)
Net loss per common share - basic and diluted		(0.08	)		(0.11	)		(0.09	)		(0.10	)
Weighted average shares used in computing net loss per common share—basic and diluted		78,241,373			78,933,884			80,491,120			80,946,849

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

12 Months Ended

Mar. 31, 2016

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 March 31, 2016 and 2015 (in thousands):
	Balance at March 31, 2016		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	4	$	—	$	—	$	4

	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 years ended March 31, 2016 and 2015:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

	Warrant Derivative Liability (in thousands)
Balance at March 31, 2014	$	377
Issuances	$	—
Adjustments to estimated fair value	$	(196	)
Warrant liability removal due to settlements	$	(55	)
Balance at March 31, 2015	$	126
Issuances	$	—
Adjustments to estimated fair value	$	17
Warrant liability removal due to settlements	$	(139	)
Balance at March 31, 2016	$	4

Research and development

Income taxes

Revenue recognition

Revenue arrangements with multiple deliverables

Revenue from research service agreements

Research and development revenue under collaborative agreements

Product revenue

Grant revenues

Stock-based compensation

Comprehensive income (loss)

Net loss per share

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

12 Months Ended

Mar. 31, 2016

Accounting Policies [Abstract]

Estimated Fair Values of Liabilities Measured on Recurring Basis

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

	Fair Value Measurements at March 31, 2016 and 2015 (in thousands):
	Balance at March 31, 2016		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	4	$	—	$	—	$	4

	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 years ended March 31, 2016 and 2015:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

	Warrant Derivative Liability (in thousands)
Balance at March 31, 2014	$	377
Issuances	$	—
Adjustments to estimated fair value	$	(196	)
Warrant liability removal due to settlements	$	(55	)
Balance at March 31, 2015	$	126
Issuances	$	—
Adjustments to estimated fair value	$	17
Warrant liability removal due to settlements	$	(139	)
Balance at March 31, 2016	$	4

Fixed Assets (Tables)

12 Months Ended

Mar. 31, 2016

Property Plant And Equipment [Abstract]

Schedule of Fixed Assets

Fixed assets consisted of the following (in thousands):

	March 31, 2016			March 31, 2015
Laboratory equipment	$	2,799		$	1,951
Construction in process		52			529
Computer software and equipment		488			274
Furniture and fixtures		337			135
Leasehold improvements		1,832			155
Vehicles		9			—
		5,517			3,044
Less accumulated depreciation and amortization		(1,806	)		(1,002	)
	$	3,711		$	2,042

Accrued Expenses (Tables)

12 Months Ended

Mar. 31, 2016

Payables And Accruals [Abstract]

Summary of Accrued Expenses

Accrued expenses consisted of the following (in thousands):

	March 31, 2016		March 31, 2015
Accrued compensation	$	2,221	$	1,917
Accrued legal and professional fees		168		195
Other accrued expenses		61		145
	$	2,450	$	2,257

Derivative Liability (Tables)

12 Months Ended

Mar. 31, 2016

Derivative Instruments And Hedging Activities Disclosure [Abstract]

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

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

	March 31, 2016			March 31, 2015
Closing price per share of common stock	$	2.17		$	3.54
Exercise price per share	$	1.00		$	1.00
Expected volatility		73.35	%		76.80	%
Risk-free interest rate		0.59	%		0.56	%
Dividend yield		—			—
Remaining expected term of underlying securities (years)		0.96			1.96

- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41641-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624163-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41678-113959

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41638-113959

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5580258-113959

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5579245-113959

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5579240-113959

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41620-113959

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(n)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Stockholders' Equity (Tables)

12 Months Ended

Mar. 31, 2016

Equity [Abstract]

Summary of Company's Restricted Stock Award Activity

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

	Number of Shares
Unvested at March 31, 2013		985,742
Granted		60,000
Vested		(472,247	)
Canceled / forfeited		—
Unvested at March 31, 2014		573,495
Granted		—
Vested		(262,245	)
Canceled / forfeited		(52,500	)
Unvested at March 31, 2015		258,750
Granted		—
Vested		(250,000	)
Canceled / forfeited		(2,500	)
Unvested at March 31, 2016		6,250

Summary of Stock Option Activity

The following table summarizes stock option activity for the years ended March 31, 2016 and 2015:

	Options Outstanding			Weighted- Average Exercise Price		Aggregate Intrinsic Value
Outstanding at March 31, 2014		5,935,888		$	4.87	$	20,482,823
Options granted		1,429,191		$	6.18
Options canceled		(45,847	)	$	7.17
Options exercised		(205,684	)	$	1.73	$	883,795
Outstanding at March 31, 2015		7,113,548		$	5.21	$	4,969,499
Options granted		2,966,778		$	3.87
Options canceled		(349,698	)	$	6.30
Options exercised		(116,001	)	$	2.76	$	112,441
Outstanding at March 31, 2016		9,614,627		$	4.79	$	1,927,137
Vested and Exercisable at March 31, 2016		5,165,836		$	4.45	$	1,860,789

Fair Value of Employee Stock Options

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

	Year Ended March 31, 2016			Year Ended March 31, 2015
Dividend yield		—			—
Volatility		73.96	%		76.90	%
Risk-free interest rate		1.57	%		1.60	%
Expected life of options	6.00 years			6.00 years
Weighted average grant date fair value	$	2.52		$	4.14

Summary of Warrant Activity

The following table summarizes warrant activity for the years ended March 31, 2016 and 2015:

	Warrants			Weighted-Average Exercise Price
Balance at March 31, 2014		1,194,756		$	1.79
Granted		195,000		$	7.04
Expired / Canceled		—			—
Exercised		(211,647	)	$	2.14
Balance at March 31, 2015		1,178,109		$	2.59
Granted		—			—
Expired / Canceled		(87,500	)	$	7.06
Exercised		(43,796	)	$	1.00
Balance at March 31, 2016		1,046,813		$	2.29

Common Stock Reserved for Future Issuance

Common stock reserved for future issuance consisted of the following at March 31, 2016:

Common stock warrants outstanding			1,046,813
Common stock options outstanding under the 2008 Plan			622,192
Common stock options outstanding and reserved under the 2012 Plan			15,479,171
Total			17,148,176

- 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)

12 Months Ended

Mar. 31, 2016

Commitments And Contingencies Disclosure [Abstract]

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

Future minimum rental payments required under operating leases that have initial or remaining non-cancelable lease terms in excess of one year as of March 31, 2016, are as follows (in thousands):

Fiscal year ended March 31, 2017	$	1,313
Fiscal year ended March 31, 2018		1,148
Fiscal year ended March 31, 2019		1,044
Fiscal year ended March 31, 2020		1,072
Fiscal year ended March 31, 2021		1,104
Thereafter		467
Total	$	6,148

Licensing Agreements and Research Contracts (Tables)

12 Months Ended

Mar. 31, 2016

Goodwill And Intangible Assets Disclosure [Abstract]

Schedule of Capitalized License Fees

Capitalized license fees consisted of the following (in thousands):

	March 31, 2016			March 31, 2015
License fees	$	148		$	114
Less accumulated amortization		(43	)		(34	)
License fees, net	$	105		$	80

Income Taxes (Tables)

12 Months Ended

Mar. 31, 2016

Income Tax Disclosure [Abstract]

Summary of Net Deferred Tax Assets

Significant components of the Company’s net deferred tax assets are as follows as of March 31, 2016 and 2015 (in thousands):

	March 31, 2016			March 31, 2015
Deferred tax assets:
Net operating loss carry forwards	$	—		$	—
Research and development credits		—			—
Depreciation and amortization		(105	)		(48	)
Accrued expenses and reserves		862			826
Stock compensation		5,584			3,462
Other, net		12			6
Total deferred tax assets		6,353			4,246
Valuation allowance		(6,353	)		(4,246	)
	$	—		$	—

Quarterly Financial Data (unaudited) (Tables)

12 Months Ended

Mar. 31, 2016

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Data

The following quarterly financial data, in the opinion of management, fairly presents the results for the periods presented (in thousands, except per share data):

	Year Ended March 31, 2016
	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
Revenue	$	306		$	301		$	328		$	548
Net loss		(8,491	)		(11,257	)		(10,455	)		(8,372	)
Net loss per common share - basic and diluted		(0.10	)		(0.12	)		(0.11	)		(0.09	)
Weighted average shares used in computing net loss per common share—basic and diluted		82,993,966			92,385,150			92,396,358			92,402,668


	Year Ended March 31, 2015
	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
Revenue	$	99		$	50		$	155		$	267
Net loss		(6,433	)		(8,858	)		(6,993	)		(7,798	)
Net loss per common share - basic and diluted		(0.08	)		(0.11	)		(0.09	)		(0.10	)
Weighted average shares used in computing net loss per common share—basic and diluted		78,241,373			78,933,884			80,491,120			80,946,849

Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) shares in Millions	1 Months Ended		12 Months Ended
	Sep. 30, 2014	Aug. 31, 2013	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2011
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit			$ (160,870,000)	$ (122,295,000)
Cash flow from operations			29,368,000	19,601,000	$ 15,561,000
Restricted cash			79,000	79,000
Inventory of raw materials, net of reserves			206,000	66,000
Inventory of work-in-process, net of reserves			15,000
Inventory of finished goods, net of reserves			$ 113,000
Estimated useful life of the fixed assets			The estimated useful lives of the fixed assets range between one and seven years.
Impairment of long-lived assets			$ 0
Revenue related to research contract			486,000	134,000	248,000
Revenue recognized under grants			191,000	123,000	131,000
Dilutive effect			$ 0	$ 0	$ 0
Common stock equivalents excluded from computing diluted net loss per share			10.7	8.6	7.7
NIH Research Grants Two [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue recognized under grants	$ 222,000
Revenue recognized under grants			$ 148,000	$ 74,000
Private, Not-for-Profit Organization [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue recognized under grants			43,000	49,000	$ 119,000
Research and Development Services [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Deferred revenue			1,110,000	259,000
Research and development services for a fixed fee						$ 1,405,000
Revenue related to research contract					184,000
Research and Development Services Two [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue related to research contract				69,000	7,000
Research and Development Services Three [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue related to research contract				41,000	$ 52,000
Research and Development Services Four [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue related to research contract			352,000
Research and Development Services Five [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue related to research contract			80,000
Research and Development Services Six [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue related to research contract			$ 50,000	$ 18,000
Maximum [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Maturity of highly liquid investment			90 days
Useful life of fixed assets, range			7 years
Maximum [Member] \| Private, Not-for-Profit Organization [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue recognized under grants		$ 251,700
Minimum [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Useful life of fixed assets, range			1 year

Description of Business and Summary of Significant Accounting Policies - Estimated Fair Values of Liabilities Measured on Recurring Basis (Detail) - Warrants [Member] - USD ($) $ in Thousands	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Fair Value, Measurements, Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrant liability	$ 4	$ 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	4	126	$ 377
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	$ 4	$ 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	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Warrant Derivative Liability, Beginning balance	$ 126	$ 377
Issuances	0	0
Adjustments to estimated fair value	17	(196)
Warrant liability removal due to settlements	(139)	(55)
Warrant Derivative Liability, Ending balance	$ 4	$ 126

Fixed Assets - Schedule of Fixed Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Mar. 31, 2015
Property Plant And Equipment [Abstract]
Laboratory equipment	$ 2,799	$ 1,951
Construction in process	52	529
Computer software and equipment	488	274
Furniture and fixtures	337	135
Leasehold improvements	1,832	155
Vehicles	9	0
Fixed assets, gross	5,517	3,044
Less accumulated depreciation and amortization	(1,806)	(1,002)
Fixed assets, net	$ 3,711	$ 2,042

Accrued Expenses - Summary of Accrued Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Mar. 31, 2015
Payables And Accruals [Abstract]
Accrued compensation	$ 2,221	$ 1,917
Accrued legal and professional fees	168	195
Other accrued expenses	61	145
Accrued expenses	$ 2,450	$ 2,257

Derivative Liability - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	Nov. 30, 2013	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2012	Mar. 31, 2011
Derivative [Line Items]
Warrants maturity term	5 years				5 years	5 years
Estimated fair value of the outstanding warrant liabilities		$ 4,000	$ 126,000
Change in fair value of warrant liabilities		$ 17,000	$ (196,000)	$ 5,120,000
Exercised derivative liabilities		43,796	8,647	1,920,874
Reclassification of warrant				269,657
Warrants [Member]
Derivative [Line Items]
Warrants issued					22,847,182	22,847,182
Estimated fair value of the outstanding warrant liabilities		$ 4,000	$ 126,000

- 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 Upon Issuance of Warrants at End of Each Reporting Period (Detail) - Warrant Derivative Liability [Member] - $ / shares	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Closing price per share of common stock	$ 2.17	$ 3.54
Exercise price per share	$ 1.00	$ 1.00
Expected volatility	73.35%	76.80%
Risk-free interest rate	0.59%	0.56%
Dividend yield	0.00%	0.00%
Remaining expected term of underlying securities (years)	11 months 16 days	1 year 11 months 16 days

Stockholders' Equity - Additional Information (Detail) - USD ($)			1 Months Ended	12 Months Ended
	Jun. 18, 2015	Aug. 02, 2013	Nov. 30, 2013	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2012	Aug. 31, 2015	Feb. 27, 2015	Aug. 31, 2013	Jul. 17, 2013	Jan. 31, 2012	May. 31, 2008
Class Of Stock [Line Items]
Issuance of common stock				92,391,989	81,536,724
Offering price per share		$ 4.50
Proceeds from issuance of common stock		$ 43,400,000
Underwriting discounts and commissions and other offering expenses		$ 3,200,000
Issuance of common stock from stock options exercises, net, Shares				116,001	205,033
Issuance of common stock from warrant exercises, net, Shares				32,914	210,600
Warrants exercised				43,796	211,647
Stock option exercised				116,001	205,684
Common stock, par value				$ 0.001	$ 0.001
Restricted stock awards issued to member of senior management				200,000
Research and development expense [Member]
Class Of Stock [Line Items]
Total employee stock-based compensation recorded as operating expenses				$ 5,000	$ 15,000	$ 16,000
General and administrative expense [Member]
Class Of Stock [Line Items]
Total employee stock-based compensation recorded as operating expenses				$ 210,000	$ 406,000	$ 801,000
Restricted stock units (RSUs) [Member]
Class Of Stock [Line Items]
Restricted stock awards vested during the period				250,000	255,000	405,000
Restricted stock surrendered				129,900	137,816	218,655
Percentage of vesting schedule							25.00%
Period for vesting schedule over start date							4 years
Stock option granted with immediate vesting				129,900	137,816	218,655
Restricted stock [Member]
Class Of Stock [Line Items]
Restricted stock awards vested during the period				250,000	262,245	472,247
Restricted stock awards granted				0	0	60,000
Common stock returned by holders				2,500
Total employee stock-based compensation recorded as operating expenses				$ 215,000	$ 421,000	$ 817,000
Unrecognized restricted stock-based compensation expense				$ 3,000
Total unrecognized compensation cost related, weighted average period				3 months
Senior Management [Member]
Class Of Stock [Line Items]
Restricted stock awards vested during the period				150,000
Restricted stock surrendered				50,000
Senior Management [Member] \| Restricted stock units (RSUs) [Member]
Class Of Stock [Line Items]
Restricted stock awards granted							950,000
Non-Executive Employees [Member] \| Restricted stock units (RSUs) [Member]
Class Of Stock [Line Items]
Restricted stock awards granted							130,000
Consultants [Member] \| Restricted stock units (RSUs) [Member]
Class Of Stock [Line Items]
Restricted stock awards granted						60,000	100,000
Percentage of vesting schedule							100.00%
Period for vesting schedule over start date							6 months
Equity Distribution Agreement [Member]
Class Of Stock [Line Items]
Value of shares sold under equity distribution agreement				$ 0	$ 16,100,000	$ 3,500,000
Issuance of common stock from stock options exercises, net, Shares				0	2,197,768	334,412
Equity Offering Sales Agreement [Member]
Class Of Stock [Line Items]
Value of shares sold under equity distribution agreement				$ 0	$ 6,200,000
Issuance of common stock from stock options exercises, net, Shares				0	1,000,000
2015 Underwriting Agreement [Member]
Class Of Stock [Line Items]
Stock option exercisable, period	30 days
Additional common stock issued on exercise of option by underwriters	1,413,750
Maximum [Member] \| Equity Distribution Agreement [Member]
Class Of Stock [Line Items]
Securities authorized for offer and sale, amount				$ 26,777,785
Number of shares to be offered and sold in equity distribution agreement			4,000,000
IPO [Member]
Class Of Stock [Line Items]
Securities authorized for offer and sale, amount									$ 190,000,000		$ 100,000,000
Secondary Offering [Member]
Class Of Stock [Line Items]
Issuance of common stock		10,350,000
Offering price per share		$ 4.23
Secondary Offering [Member] \| 2015 Underwriting Agreement [Member]
Class Of Stock [Line Items]
Offering price per share	$ 4.25
Issuance of common stock from stock options exercises, net, Shares	10,838,750
Common stock, par value	$ 0.001
Gross proceeds from sale of common stock shares	$ 43,100,000
Over Allotment Option [Member] \| 2015 Underwriting Agreement [Member]
Class Of Stock [Line Items]
Issuance of common stock	9,425,000
Sale of stock price per share net of fees	$ 3.995
Equity Incentive Plan 2008 [Member]
Class Of Stock [Line Items]
Common shares authorized to be issued													1,521,584
Termination date of Equity Incentive Plan				Jul. 01, 2018
Shares issued during the year				0
Equity Incentive Plan 2012 [Member]
Class Of Stock [Line Items]
Common shares authorized to be issued								6,000,000		5,000,000		6,553,986
Shares available for issuance				6,486,736				17,553,986
Termination period of Equity Incentive Plan				10 years
Underwriting Agreement [Member] \| Over Allotment Option [Member]
Class Of Stock [Line Items]
Issuance of common stock		1,350,000

Stockholders' Equity - Summary of Company's Restricted Stock Award Activity (Detail) - Restricted stock [Member] - shares	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Class Of Stock [Line Items]
Beginning balance, Unvested, Number of Shares	258,750	573,495	985,742
Granted, Number of Shares	0	0	60,000
Vested, Number of Shares	(250,000)	(262,245)	(472,247)
Canceled / forfeited, Number of Shares	(2,500)	(52,500)	0
Ending balance, Unvested, Number of Shares	6,250	258,750	573,495

Stockholders' Equity - Additional Information 1 (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Class Of Stock [Line Items]
Issuances of common stock from stock option exercises, Shares	116,001	205,684
Weighted-average remaining contractual term of options exercisable	6 years 1 month 28 days
Weighted-average remaining contractual term of options outstanding	6 years 1 month 28 days
Total unrecognized compensation cost related to unvested stock option grants	$ 13,385,000
Research and development expense [Member]
Class Of Stock [Line Items]
Total employee stock-based compensation recorded as operating expenses	5,000	$ 15,000	$ 16,000
General and administrative expense [Member]
Class Of Stock [Line Items]
Total employee stock-based compensation recorded as operating expenses	$ 210,000	$ 406,000	801,000
2012 Plan [Member]
Class Of Stock [Line Items]
Issuances of common stock from stock option exercises, Shares	2,966,778	1,429,191
Remaining options vest	36 months
Incentive stock option grants	0	56,500
2012 Plan [Member] \| One Year Vesting [Member]
Class Of Stock [Line Items]
Incentive stock option grants	185,000	128,500
Stock options [Member]
Class Of Stock [Line Items]
Total employee stock-based compensation recorded as operating expenses	$ 8,341,000	$ 6,599,000	3,783,000
Total unrecognized compensation cost related, weighted average period	2 years 5 months 23 days
Stock options [Member] \| Research and development expense [Member]
Class Of Stock [Line Items]
Total employee stock-based compensation recorded as operating expenses	$ 1,243,000	1,175,000	462,000
Stock options [Member] \| General and administrative expense [Member]
Class Of Stock [Line Items]
Total employee stock-based compensation recorded as operating expenses	$ 7,098,000	$ 5,424,000	$ 3,321,000
Stock options [Member] \| 2012 Plan [Member]
Class Of Stock [Line Items]
Award vesting conditions	stock options generally vest on the one year anniversary of the grant date, quarterly over a three year period, or over a four-year period, with a quarter vesting on either the one year anniversary of employment or the one year anniversary of the vesting commencement date
Restricted stock units (RSUs) [Member]
Class Of Stock [Line Items]
Stock option granted with immediate vesting	129,900	137,816	218,655
Restricted stock units (RSUs) [Member] \| 2012 Plan [Member]
Class Of Stock [Line Items]
Stock option granted with immediate vesting	129,900	139,316

Stockholders' Equity - Summary of Stock Option Activity (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Options Outstanding, Beginning balance	7,113,548	5,935,888
Granted, Options Outstanding	2,966,778	1,429,191
Canceled, Options Outstanding	(349,698)	(45,847)
Exercised, Options Outstanding	(116,001)	(205,684)
Options Outstanding, Ending balance	9,614,627	7,113,548
Vested and Exercisable, Options Outstanding	5,165,836
Weighted-Average Exercise Price, Options Beginning balance	$ 5.21	$ 4.87
Options granted, Weighted-Average Exercise Price	3.87	6.18
Options canceled, Weighted-Average Exercise Price	6.30	7.17
Options exercised, Weighted-Average Exercise Price	2.76	1.73
Weighted-Average Exercise Price, Options Ending balance	4.79	$ 5.21
Vested and Exercisable, Weighted-Average Exercise Price	$ 4.45
Aggregate Intrinsic Value, Options Beginning balance	$ 4,969,499	$ 20,482,823
Options Exercised, Aggregate Intrinsic Value	112,441	883,795
Aggregate Intrinsic Value, Options Ending balance	1,927,137	$ 4,969,499
Vested and Exercisable, Aggregate Intrinsic Value	$ 1,860,789

Stockholders' Equity - Fair Value of Employee Stock Options (Detail) - $ / shares	1 Months Ended		12 Months Ended
	Nov. 30, 2014	Nov. 30, 2013	Mar. 31, 2016	Mar. 31, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Dividend yield			0.00%	0.00%
Volatility	73.40%	96.90%	73.96%	76.90%
Risk-free interest rate	1.21%	0.60%	1.57%	1.60%
Expected life of options			6 years	6 years
Weighted average grant date fair value			$ 2.52	$ 4.14

Stockholders' Equity - Additional Information 2 (Detail) - USD ($)		1 Months Ended			12 Months Ended
	Dec. 31, 2014	Nov. 30, 2014	Sep. 30, 2014	Nov. 30, 2013	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2012	Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Class Of Stock [Line Items]
Purchase shares of common stock for issued warrants								21,347,182			2,909,750
Cash proceeds from warrant exercises					$ 139,000	$ 55,000	$ 10,874,000
Exercised derivative liabilities					43,796	8,647	1,920,874
Warrants to purchase common stock		145,000		75,000	1,370			650,000
Interest expense					$ 0	$ 1,000	$ 13,000
Warrants maturity term				5 years					5 years	5 years
Volatility		73.40%		96.90%	73.96%	76.90%
Risk-free interest rate		1.21%		0.60%	1.57%	1.60%
Recognized expenses of warrants					$ 0	$ 43,000
Warrants earned, service period				12 months
Warrants issued			50,000
Number of warrant shares vested upon satisfaction of specific performance metrics					95,000
Weighted-average remaining contractual term of options exercisable					6 years 1 month 28 days
Preferred stock, shares authorized					25,000,000
Preferred stock, shares outstanding					0
Consultation Service Agreement September 2014
Class Of Stock [Line Items]
Recognized expenses of warrants	$ 237,000
Consultation Service Agreement November 2014
Class Of Stock [Line Items]
Recognized expenses of warrants					$ 41,000	$ 36,000
Minimum [Member]
Class Of Stock [Line Items]
Warrants exercisable price, per share					$ 0.85
Warrants maturity term								2 years
Maximum [Member]
Class Of Stock [Line Items]
Warrants exercisable price, per share					$ 7.62
Warrants maturity term								5 years
Amendment March 2014 [Member]
Class Of Stock [Line Items]
Warrants exercisable price, per share							$ 1.00
Warrants to purchase common stock							269,657
Amendment March 2014 [Member] \| Minimum [Member]
Class Of Stock [Line Items]
Warrants exercisable price, per share							$ 0.85
Warrants [Member]
Class Of Stock [Line Items]
Number of warrants exercised					0	203,000	225,000
Cash proceeds from warrant exercises					$ 0	$ 445,000	$ 210,000
Number of warrant exercised through cashless					43,796	8,647	2,628,003
Cashless exercise for issuance of common stock					32,914	7,600	2,139,577
Warrants exercisable price, per share		$ 6.84		$ 7.36
Estimated fair value of warrants		$ 74,000		$ 404,000
Weighted-average remaining contractual term of options exercisable					1 year 3 months 11 days
Warrants [Member] \| Consultants [Member]
Class Of Stock [Line Items]
Number of warrants exercised					0	0	348,630
Cash proceeds from warrant exercises							$ 891,000
Warrants [Member] \| Minimum [Member]
Class Of Stock [Line Items]
Warrants exercisable price, per share								$ 1.70
Warrants [Member] \| Maximum [Member]
Class Of Stock [Line Items]
Warrants exercisable price, per share								$ 3.24
Warrants [Member] \| Amendment March 2014 [Member]
Class Of Stock [Line Items]
Interest expense							$ 12,000

Stockholders' Equity - Summary of Warrant Activity (Detail) - $ / shares	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options Outstanding, Beginning balance	7,113,548	5,935,888
Granted, Options Outstanding	2,966,778	1,429,191
Expired / Canceled, Options Outstanding	(349,698)	(45,847)
Exercised, Options Outstanding	(116,001)	(205,684)
Options Outstanding, Ending balance	9,614,627	7,113,548
Weighted-Average Exercise Price, Options Beginning balance	$ 5.21	$ 4.87
Granted, Weighted-Average Exercise Price	3.87	6.18
Options canceled, Weighted-Average Exercise Price	6.30	7.17
Exercised, Weighted-Average Exercise Price	2.76	1.73
Weighted-Average Exercise Price, Options Ending balance	$ 4.79	$ 5.21
Warrants [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options Outstanding, Beginning balance	1,178,109	1,194,756
Granted, Options Outstanding	0	195,000
Expired / Canceled, Options Outstanding	(87,500)	0
Exercised, Options Outstanding	(43,796)	(211,647)
Options Outstanding, Ending balance	1,046,813	1,178,109
Weighted-Average Exercise Price, Options Beginning balance	$ 2.59	$ 1.79
Granted, Weighted-Average Exercise Price	0	7.04
Options canceled, Weighted-Average Exercise Price	7.06	0
Exercised, Weighted-Average Exercise Price	1.00	2.14
Weighted-Average Exercise Price, Options Ending balance	$ 2.29	$ 2.59

Stockholders' Equity - Common Stock Reserved for Future Issuance (Detail)	Mar. 31, 2016 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance	17,148,176
Warrants [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance	1,046,813
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	15,479,171

Commitments and Contingencies - Additional Information (Detail)			12 Months Ended			45 Months Ended
	Dec. 28, 2015 USD ($) ft²	Jan. 09, 2015 USD ($) ft²	Mar. 31, 2016 USD ($) ft² Lease	Mar. 31, 2015 USD ($)	Mar. 31, 2014 USD ($)	Mar. 31, 2016 USD ($) Lease
Commitments And Contingencies Disclosure [Abstract]
Number of non-cancelable leases \| Lease			3			3
Office space under lease agreement \| ft²			30,895
Rent expense per month			$ 83,000
Base rent escalators		3.00%	3.00%			3.00%
Lease expiration date			Sep. 01, 2021
Lease option termination description			option to terminate on or after September 1, 2019.
Additional office space \| ft²			14,500
Area of leased office space \| ft²	12,088	5,803
Lease term	12 months	36 months
Base rent under the lease	$ 15,000	$ 12,000
Lease rental period start date	Feb. 01, 2016	Feb. 01, 2015
Lease rental period end date	Jan. 31, 2017	Jan. 31, 2018
Leasehold improvements			$ 374,000	$ 144,000		$ 518,000
Rent expense			$ 1,088,000	$ 968,000	$ 561,500

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) $ in Thousands	Mar. 31, 2016 USD ($)
Commitments And Contingencies Disclosure [Abstract]
Fiscal year ended March 31, 2017	$ 1,313
Fiscal year ended March 31, 2018	1,148
Fiscal year ended March 31, 2019	1,044
Fiscal year ended March 31, 2020	1,072
Fiscal year ended March 31, 2021	1,104
Thereafter	467
Total	$ 6,148

Licensing Agreements and Research Contracts - Additional Information (Detail) - USD ($)	1 Months Ended			12 Months Ended
	May. 31, 2011	Mar. 31, 2010	Mar. 31, 2009	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Licensing Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense of licenses					$ 9,700	$ 8,500	$ 8,500
Weighted average remaining amortization period for all licenses					11 years
Annual amortization expense of licenses year 1					$ 10,300
Annual amortization expense of licenses year 2					10,300
Annual amortization expense of licenses year 3					10,300
Annual amortization expense of licenses year 4					10,300
Annual amortization expense of licenses year 5					10,300
University of Missouri [Member]
Finite-Lived Intangible Assets [Line Items]
Royalty fees percentage minimum		1.00%	1.00%
Royalty fees percentage maximum		3.00%	3.00%
Expected expiration year of license agreement			2029
Clemson University [Member]
Finite-Lived Intangible Assets [Line Items]
Minimum annual royalty payment due					$ 40,000	$ 20,000	$ 20,000
Clemson University [Member] \| Licensing Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Royalty fees percentage minimum	1.50%
Royalty fees percentage maximum	3.00%
Expected expiration year of license agreement	2024-05
Scenario Forecast [Member] \| University of Missouri [Member]
Finite-Lived Intangible Assets [Line Items]
Annual royalty				$ 25,000

Licensing Agreements and Research Contracts - Schedule of Capitalized License Fees (Detail) - Licensing Agreements [Member] - USD ($) $ in Thousands	Mar. 31, 2016	Mar. 31, 2015
Finite-Lived Intangible Assets [Line Items]
License fees	$ 148	$ 114
Less accumulated amortization	(43)	(34)
License fees, net	$ 105	$ 80

Income Taxes - Summary of Net Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Mar. 31, 2015
Deferred tax assets:
Net operating loss carry forwards	$ 0	$ 0
Research and development credits	0	0
Depreciation and amortization	(105)	(48)
Accrued expenses and reserves	862	826
Stock compensation	5,584	3,462
Other, net	12	6
Total deferred tax assets	6,353	4,246
Valuation allowance	(6,353)	(4,246)
Deferred tax assets net	$ 0	$ 0

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Operating Loss Carryforwards [Line Items]
Unrecognized tax benefits	$ 0
Increase (decrease) in valuation allowance	2,107,000	$ 2,002,000
Federal net operating loss carryforwards	89,814,000
State net operating loss carryforwards	$ 89,063,000
Federal and state net operating loss carryforwards expiring year	2028
Net operating loss carryforwards related to windfall tax benefits	$ 6,332,000
Federal research tax credit carryforwards expiration period	2028
Accrued expense regarding interest or penalties	$ 0
Federal [Member]
Operating Loss Carryforwards [Line Items]
Research tax credit carryforwards	1,351,000
State [Member]
Operating Loss Carryforwards [Line Items]
Research tax credit carryforwards	$ 1,578,000

Quarterly Financial Data (unaudited) - Schedule of Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 548	$ 328	$ 301	$ 306	$ 267	$ 155	$ 50	$ 99	$ 1,483	$ 571	$ 379
Net loss	$ (8,372)	$ (10,455)	$ (11,257)	$ (8,491)	$ (7,798)	$ (6,993)	$ (8,858)	$ (6,433)	$ (38,575)	$ (30,082)	$ (25,848)
Net loss per common share - basic and diluted	$ (0.09)	$ (0.11)	$ (0.12)	$ (0.10)	$ (0.10)	$ (0.09)	$ (0.11)	$ (0.08)	$ (0.43)	$ (0.38)	$ (0.35)
Weighted average shares used in computing net loss per common share—basic and diluted	92,402,668	92,396,358	92,385,150	82,993,966	80,946,849	80,491,120	78,933,884	78,241,373	90,057,356	79,650,087	73,139,618

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Defined Contribution Plan	12 Months Ended
Defined Contribution Plan	Mar. 31, 2016
Defined Benefit Pension Plans And Defined Benefit Postretirement Plans Disclosure [Abstract]
Defined Contribution Plan	10. Defined Contribution Plan The Company has a defined contribution 401(k) plan covering substantially all employees. During the year ended March 31, 2015, the 401(k) plan was amended (“the Amended Plan”) to include an employer matching provision. Under the terms of the Amended Plan, the Company will make matching contributions on up to the first 6 % of compensation contributed by its employees. Amounts expensed under the Company’s 401(k) plan for the years ended March 31, 2016 and 2015 were approximately $277,000 and $57,000, respectively.

Subsequent Events	12 Months Ended
Subsequent Events	Mar. 31, 2016
Subsequent Events [Abstract]
Subsequent Events	13. Subsequent Events None.

Defined Contribution Plan - Additional Information (Details) - USD ($)	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Defined Benefit Pension Plans And Defined Benefit Postretirement Plans Disclosure [Abstract]
Percentage of employees contribution	6.00%
Administration expenses	$ 277,000	$ 57,000