Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Mar. 31, 2017	Jun. 01, 2017	Sep. 30, 2016
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Mar. 31, 2017
Document Fiscal Year Focus	2017
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		104,584,831
Entity Public Float			$ 355,315,767

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2017	Mar. 31, 2016
Current Assets
Cash and cash equivalents	$ 62,751	$ 62,091
Accounts receivable	647	259
Inventory, net	550	334
Prepaid expenses and other current assets	1,144	968
Total current assets	65,092	63,652
Fixed assets, net	3,840	3,711
Restricted cash	127	79
Other assets, net	121	134
Total assets	69,180	67,576
Current Liabilities
Accounts payable	1,171	787
Accrued expenses	4,101	2,450
Deferred rent	157	139
Deferred revenue	582	1,110
Warrant liabilities	0	4
Total current liabilities	6,011	4,490
Deferred revenue, net of current portion	58	0
Deferred rent, net of current portion	749	905
Total liabilities	6,818	5,395
Commitments and Contingencies (Note 6)	0	0
Stockholders’ Equity
Common stock, $0.001 par value; 150,000,000 shares authorized, 104,551,466 and 92,391,989 shares issued and outstanding at March 31, 2017 and March 31, 2016, respectively	104	92
Additional paid-in capital	261,586	222,959
Accumulated deficit	(199,317)	(160,870)
Accumulated other comprehensive income (loss)	(11)	0
Total stockholders’ equity	62,362	62,181
Total Liabilities and Stockholders’ Equity	$ 69,180	$ 67,576

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2017	Mar. 31, 2016
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	104,551,466	92,391,989
Common stock, shares outstanding	104,551,466	92,391,989

Consolidated Statements of Operations and Other Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Revenues
Products and services	$ 3,167	$ 806	$ 314
Collaborations	1,022	486	134
Grants	41	191	123
Total Revenues	4,230	1,483	571
Cost of revenues	956	0	0
Research and development expenses	19,545	18,008	12,921
Selling, general, and administrative expense	22,304	22,118	17,947
Total costs and expenses	42,805	40,126	30,868
Loss from Operations	(38,575)	(38,643)	(30,297)
Other Income (Expense)
Change in fair value of warrant liabilities	4	(17)	196
Loss on disposal of fixed assets	(51)	0	(12)
Interest expense	0	0	(1)
Interest income	198	88	32
Total Other Income (Expense)	151	71	215
Income Tax Expense	(23)	(3)	0
Net Loss	$ (38,447)	$ (38,575)	$ (30,082)
Net loss per common share—basic and diluted	$ (0.39)	$ (0.43)	$ (0.38)
Weighted average shares used in computing net loss per common share—basic and diluted	97,763,032	90,057,356	79,650,087
Comprehensive Loss:
Net Loss	$ (38,447)	$ (38,575)	$ (30,082)
Currency Translation Adjustment	(11)	0	0
Comprehensive Loss	$ (38,458)	$ (38,575)	$ (30,082)

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning balance at Mar. 31, 2014	$ 48,284	$ 78	$ 140,419	$ (92,213)	$ 0
Beginning balance, Shares at Mar. 31, 2014		78,113,000
Issuance of common stock from warrant exercises, net	$ 445	$ 0	445	0	0
Issuance of common stock from warrant exercises, net, Shares	210,600	211,000
Restricted stock forfeitures	$ 0	$ 0	0	0	0
Restricted stock forfeitures, Shares		(190,000)
Issuance of common stock from public offering, net	22,307	$ 4	22,303	0	0
Issuance of common stock from public offering, Shares		3,198,000
Stock-based compensation expense	7,020	$ 0	7,020	0	0
Warrant liability removed due to exercises of warrants	55	0	55	0	0
Stock option exercises	$ 351	$ 0	351	0	0
Stock option exercises, Shares	205,684	205,000
Issuance of warrants to consultant	$ 316	$ 0	316	0	0
Net loss	(30,082)	0	0	(30,082)	0
Foreign currency translation adjustment	0
Ending balance at Mar. 31, 2015	48,696	$ 82	170,909	(122,295)	0
Ending balance, Shares at Mar. 31, 2015		81,537,000
Issuance of common stock from warrant exercises, net	$ 0	$ 0	0	0	0
Issuance of common stock from warrant exercises, net, Shares	32,914	32,000
Restricted stock forfeitures	$ 0	$ 0	0	0	0
Restricted stock forfeitures, Shares		(132,000)
Issuance of common stock from public offering, net	43,137	$ 10	43,127	0	0
Issuance of common stock from public offering, Shares		10,839,000
Stock-based compensation expense	8,556	$ 0	8,556	0	0
Warrant liability removed due to exercises of warrants	139	0	139	0	0
Stock option exercises	$ 320	$ 0	320	0	0
Stock option exercises, Shares	116,001	116,000
Issuance of warrants to consultant	$ 38	$ 0	38	0	0
Adjustment related to potential equity bonus issuance	(130)	0	(130)	0	0
Net loss	(38,575)	0	0	(38,575)	0
Foreign currency translation adjustment	0
Ending balance at Mar. 31, 2016	62,181	$ 92	222,959	(160,870)	0
Ending balance, Shares at Mar. 31, 2016		92,392,000
Issuance of common stock from warrant exercises, net	$ 336	$ 1	335	0	0
Issuance of common stock from warrant exercises, net, Shares	700,379	700,000
Issuance of common stock under employee and director stock option, RSU and purchase plans	$ 705	$ 0	705	0	0
Issuance of common stock under employee and director stock option, RSU and purchase plans, Shares		397,000
Issuance of common stock from public offering, net	30,206	$ 11	30,195	0	0
Issuance of common stock from public offering, Shares		11,062,000
Stock-based compensation expense	$ 7,392	$ 0	7,392	0	0
Stock option exercises, Shares	245,271
Net loss	$ (38,447)	0	0	(38,447)
Foreign currency translation adjustment	(11)	0	0	0	(11)
Ending balance at Mar. 31, 2017	$ 62,362	$ 104	$ 261,586	$ (199,317)	$ (11)
Ending balance, Shares at Mar. 31, 2017		104,551,000

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Cash Flows From Operating Activities
Net loss	$ (38,447)	$ (38,575)	$ (30,082)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of warrants issued for services	0	(92)	557
Depreciation and amortization	1,149	815	472
Loss on disposal of fixed assets	56	0	12
Change in fair value of warrant liabilities	(4)	17	(196)
Stock-based compensation	7,392	8,556	7,020
Increase (decrease) in cash resulting from changes in:
Accounts receivable	(388)	(259)	0
Inventory	(216)	(268)	(3)
Prepaid expenses and other assets	(154)	83	(389)
Accounts payable	384	(600)	1,061
Accrued expenses	1,651	193	1,435
Deferred rent	(138)	(89)	270
Deferred revenue	(470)	851	242
Net cash used in operating activities	(29,185)	(29,368)	(19,601)
Cash Flows From Investing Activities
Deposits released from restriction (restricted cash deposits)	(48)	0	0
Purchases of fixed assets	(1,354)	(2,114)	(1,517)
Proceeds from disposals of fixed assets	11	14	0
Purchases of intangible assets	0	(35)	0
Net cash used in investing activities	(1,391)	(2,135)	(1,517)
Cash Flows From Financing Activities
Proceeds from issuance of common stock and exercise of warrants, net	30,665	43,137	22,752
Proceeds from exercise of stock options	582	320	351
Principal payments on capital lease obligations	0	(5)	(10)
Net cash provided by financing activities	31,247	43,452	23,093
Effect of currency exchange rate changes on cash and cash equivalents	(11)	0	0
Net Increase in Cash and Cash Equivalents	660	11,949	1,975
Cash and Cash Equivalents at Beginning of Period	62,091	50,142	48,167
Cash and Cash Equivalents at End of Period	62,751	62,091	50,142
Supplemental Disclosure of Cash Flow Information:
Income Taxes	$ 23	$ 3	$ 4

Description of Business and Summary of Significant Accounting Policies

12 Months Ended

Mar. 31, 2017

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 diseased 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 ExVive™ Human Liver Tissue for use in toxicology and other preclinical drug testing. In September 2016, the Company announced that it had begun commercial contracting for services relating to its second product, the ExVive™ Human Kidney tissue.

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 to achieve and sustain profitability.

NASDAQ listing

On August 8, 2016, the Company moved its stock exchange listing to the NASDAQ Global Market, under the “ONVO” ticker symbol. From July 11, 2013 through August 5, 2016, the Company listed its shares on the NYSE MKT. Prior to July 11, 2013, the Company’s shares were quoted on the OTC QX.

Liquidity

As of March 31, 2017, the Company had an accumulated deficit of approximately $199.3 million. The Company also had negative cash flows from operations of approximately $29.2 million during the year ended March 31, 2017.

Through March 31, 2017, 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 diseased 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 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. As of March 31, 2017, the Company does not have any derivative liabilities measured on a fair value basis.

Historically, the Company reviewed the terms of convertible debt and equity instruments it issued to determine if they were 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 were accounted for as a single, compound derivative instrument. Also, in connection with the sale of convertible debt and equity instruments, the Company may have issued freestanding warrants that may, depending on their terms, have been accounted for as derivative instrument liabilities, rather than as equity.

Derivative instruments were initially recorded at fair value and were 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 were to be bifurcated and accounted for as liabilities, the total proceeds allocated to the convertible host instruments were first allocated to the fair value of all the bifurcated derivative instruments. The remaining proceeds, if any, were 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, was amortized over the life of the instrument through periodic charges to interest expense, using the effective interest method.

Foreign Currency

The functional currency of our wholly owned subsidiary in the United Kingdom is the pound sterling. Accordingly, all assets and liabilities of this subsidiary are translated to US dollars based on the applicable exchange rate on the balance sheet date. Revenue and expense components are translated to US dollars at the exchange rates in effect during the period. Gains and losses resulting from foreign currency translation are reported as a separate component of accumulated other comprehensive income or loss in the equity section of our consolidated balance sheets.

Foreign currency transaction gains and losses, which are primarily the result of remeasuring US dollar-denominated receivables and payables, are recorded in our consolidated statements of operations and other comprehensive loss. For the years ended March 31, 2017, 2016 and 2015, we recognized foreign currency translation losses of approximately $11,000, $0 and $0, respectively.

Restricted cash

As of March 31, 2017 and 2016, the Company had approximately $127,000 and $79,000 of restricted cash, respectively, 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, 2017 consists of approximately $467,000 in raw materials, approximately $83,000 in work-in-process inventory, and approximately $0 in finished goods. Inventory at March 31, 2016 consisted of approximately $206,000 in raw materials, approximately $15,000 in work-in progress inventory, and approximately $113,000 in finished goods.

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, 2017.

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 had issued warrants, of which some were 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 used 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 were 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 were considered in the pricing models we used 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.

During the years ended March 31, 2017, 2016 and 2015, the Company valued its derivative liabilities in accordance with ASC 820. The remaining warrants expired as of March 31, 2017 and were removed from the Balance Sheet. The Company does not have any financial assets or liabilities measured on a fair value basis as of March 31, 2017.

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

	Fair Value Measurements at March 31, 2017 and 2016 (in thousands):
	Balance at March 31, 2017		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	—	$	—	$	—	$	—

	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

The following table presents the activity for liabilities measured at estimated fair value using unobservable inputs for the years ended March 31, 2017 and 2016:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

	Warrant Derivative Liability (in thousands)
Balance at March 31, 2015	$	126
Issuances	$	—
Adjustments to estimated fair value	$	17
Warrant liability removal due to settlements	$	(139	)
Balance at March 31, 2016	$	4
Issuances	$	—
Adjustments to estimated fair value	$	(4	)
Warrant liability removal due to settlements	$	—
Balance at March 31, 2017	$	—

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, 2017 and 2016, the Company had approximately $640,000 and $1,110,000, 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. The Company recognizes 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 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 for the year ended March 31, 2015 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 for the year ended March 31, 2015 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 completed its obligations under this agreement during the year ended March 31, 2017. The Company recorded approximately $32,000, $50,000 and $18,000 for the years ended March 31, 2017, 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 years ended March 31, 2017 and 2016, the Company has recorded approximately $117,000 and $352,000, respectively, in collaboration revenue.

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 $835,000 and $80,000 under this agreement was recognized as revenue in recognition of the proportional performance achieved during the years ended March 31, 2017 and 2016, respectively.

In June 2016, the Company announced it had entered into another 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 skeletal disease research. The Company received an up-front payment in June 2016, which has initially been recorded as deferred revenue. Revenue of $34,000 has been recorded under this agreement during the year ended March 31, 2017.

In December 2016, the Company signed another 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 an architecturally correct kidney for potential therapeutic applications. The Company received up-front payments in January and March of 2017, which has been recorded as deferred revenue. Revenue of $3,000 has been recorded under this agreement during the year ended March 31, 2017.

Product revenue

The Company recognizes product revenue at the time of shipment to the customer, provided all other revenue recognition criteria have been met.

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.

Cost of revenue

We reported $1.0 million in cost of revenue for the year ended March 31, 2017. This is our first full year reporting this cost line item, which reflects costs related to manufacturing and delivering our product and service. Cost of revenue for the year ended March 31, 2016 was minimal and was included in research and development expense.

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. The Company completed its obligations under this agreement during the year ended March 31, 2017. Revenue recognized under this grant was approximately $41,000, $43,000 and $49,000 for the years ended March 31, 2017, 2016 and 2015, 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. The Company completed its obligations under this agreement during the year ended March 31, 2016. Revenue recognized under this grant was approximately $0, $148,000, and $74,000 for the years ended March 31, 2017, 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, 2017, 2016 and 2015, the comprehensive loss was materially equal to the net loss, and consisted of net loss and foreign currency translation.

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, 2017, 2016 and 2015 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 12.4 million, 10.7 million, and 8.6 million for the years ended March 31, 2017, 2016 and 2015, respectively.

Fixed Assets

12 Months Ended

Mar. 31, 2017

Property Plant And Equipment [Abstract]

Fixed Assets

2. Fixed Assets

Fixed assets consisted of the following (in thousands):

	March 31, 2017			March 31, 2016
Laboratory equipment	$	3,727		$	2,799
Construction in process		—			52
Computer software and equipment		656			488
Furniture and fixtures		319			337
Leasehold improvements		2,045			1,832
Vehicles		9			9
		6,756			5,517
Less accumulated depreciation		(2,916	)		(1,806	)
	$	3,840		$	3,711

Depreciation expense for the years ended March 31, 2017, 2016 and 2015 was approximately $1,139,000, $805,000, and $464,000, respectively.

Accrued Expenses

12 Months Ended

Mar. 31, 2017

Payables And Accruals [Abstract]

Accrued Expenses

3. Accrued Expenses

Accrued expenses consisted of the following (in thousands):

	March 31, 2017		March 31, 2016
Accrued compensation	$	3,318	$	2,221
Accrued legal and professional fees		572		168
Other accrued expenses		211		61
	$	4,101	$	2,450

Derivative Liability

12 Months Ended

Mar. 31, 2017

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. 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 $0 and $4,000 as of March 31, 2017 and 2016, respectively. The change in fair value of the derivative liabilities for the year ended March 31, 2017 was a decrease of $4,000. The changes in fair value of the derivative liabilities for the years ended March 31, 2016 and 2015 were an increase of $17,000 and a decrease of $196,000, respectively. These changes are included in other income (expense) in the statements of operations.

During the years ended March 31, 2017 and 2016, 0 and 43,796 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. During the year ended March 31, 2017, 3,350 warrants expired. As of March 31, 2017, all warrants subject to derivative treatment have been exercised or have expired.

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
Closing price per share of common stock	$	2.17
Exercise price per share	$	1.00
Expected volatility		73.35	%
Risk-free interest rate		0.59	%
Dividend yield		—
Remaining expected term of underlying securities (years)		0.96

- 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
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 1
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 30
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-Paragraph 2
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
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Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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-Paragraph 4H
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Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5708773-113959

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

Reference 16: http://www.xbrl.org/2003/role/presentationRef
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Reference 17: http://www.xbrl.org/2003/role/presentationRef
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-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
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-URI http://asc.fasb.org/extlink&oid=64837297&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, 2017

Equity [Abstract]

Stockholders' Equity

5. Stockholders’ Equity

Stock-based compensation expense and valuation information

Stock-based compensation expense for all stock awards consists of the following (in thousands):

	Year Ended March 31, 2017		Year Ended March 31, 2016 (1)		Year Ended March 31, 2015
Research and development	$	1,646	$	1,248	$	1,190
General and administrative	$	5,746	$	7,308	$	5,830
Total	$	7,392	$	8,556	$	7,020

(1)

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, 2017 was approximately $10,271,000 and the weighted average period over which these grants are expected to vest is 2.20 years.

The total unrecognized stock-based compensation expense related to restricted stock units as of March 31, 2017 was approximately $3,557,000, which will be recognized over a weighted average period of 2.86 years.

As of March 31, 2017, there was no unrecognized stock-based compensation expense for restricted stock awards.

The Company calculates the grant date fair value of all stock-based awards in determining the stock-based compensation expense. Stock-based awards include (i) stock options, (ii) restricted stock awards, (iii) restricted stock units, and (iv) options to purchase stock granted under the 2016 Employee Stock Purchase Plan (“ESPP”).

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, 2017			Year Ended March 31, 2016			Year Ended March 31, 2015
Dividend yield		—			—			—
Volatility		72.17	%		73.96	%		76.90	%
Risk-free interest rate		1.16	%		1.57	%		1.60	%
Expected life of options	6.00 years			6.00 years			6.00 years
Weighted average grant date fair value	$	2.41		$	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 fair value of each restricted stock award is recognized as stock-based compensation expense over the vesting term of the award. The fair value is based on the closing stock price on the date of the grant.

The fair value of each restricted stock unit is recognized as stock-based compensation expense over the vesting term of the award. The fair value is based on the closing stock price on the date of the grant.

The Company uses the Black-Scholes valuation model to calculate the fair value of shares issued pursuant to the Company’s ESPP. Stock-based compensation expense is recognized over the purchase period using the straight-line method. The fair value of ESPP shares was estimated at the purchase period commencement date using the following weighted average assumptions:

	Year Ended March 31, 2017
Dividend yield		—
Volatility	72.89 % - 74.70 %
Risk-free interest rate	0.47 % - 0.79 %
Expected term	6 months
Grant date fair value	$	1.04 - 1.22

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.

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, 2017, 3,617,386 shares remain available for issuance under the 2012 plan.

On April 24, 2017 the Company filed a Registration Statement on Form S-8 with the SEC authorizing the issuance of 2,297,034 shares of the Company’s Common Stock, pursuant to the terms of an Inducement Award Stock Option Agreement and an Inducement Award Performance-Based Restricted Stock Unit Agreement (collectively, the “Inducement Award Agreements”).

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.

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 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, 2017, 2016 and 2015, the Company issued 0, 0 and 2,197,768 shares of common stock in at-the-market offerings under the distribution agreement with net proceeds of $0, $0 and $16.1 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, 2017, 2016, and 2015, the Company issued 997,181, 0, and 1,000,000 shares of common stock in at-the-market offerings under the sales agreement with net proceeds of $4.6 million, $0, and $6.2 million, respectively. As of March 31, 2017, the Company has sold an aggregate of 1,997,181 shares of common stock in at-the-market offerings under the 2014 Sales Agreement, with net proceeds of approximately $10.8 million.

On July 20, 2016, the Company filed a prospectus supplement to move the remaining shares of common stock that previously could have been sold pursuant to the 2014 Sales Agreement under the 2013 Shelf to the 2015 Shelf, which does not expire until March 17, 2018. On the same date, the Company filed a post-effective amendment to the 2013 Shelf de-registering all remaining securities that could have been offered by the Company pursuant to the 2013 Shelf. Based on sales through March 31, 2017, the Company can sell an additional $21.9 million of shares pursuant to the 2014 Sales Agreement under the 2015 Shelf. 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.

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.

On October 25, 2016, the Company closed the issuance and sale of 10,065,000 shares (the “2016 Offering”) of its common stock. The 2016 Offering was effected pursuant to an Underwriting Agreement (the “2016 Underwriting Agreement”), dated October 20, 2016, with Jefferies LLC (the “Representative”), acting as representative of the underwriters named in the 2016 Underwriting Agreement. The price to the public in the 2016 Offering was $2.75 per share, and the underwriters purchased the shares from the Company pursuant to the 2016 Underwriting Agreement at a price of $2.585 per share. The net proceeds to the Company from the 2016 Offering were approximately $25.7 million after deducting underwriting discounts and commissions and expenses payable by the Company. The 2016 Offering was made pursuant to the Company’s 2015 Shelf.

In addition, during the years ended March 31, 2017, 2016, and 2015, the Company issued 700,379, 32,914, and 210,600 shares of common stock upon exercise of 822,903, 43,796, and 211,647 warrants, respectively.

During the years ended March 31, 2017, 2016, and 2015, the Company issued 245,271, 116,001, and 205,033 shares of common stock upon exercise of 245,271, 116,001, and 205,684 stock options, respectively.

Restricted stock awards

On August 6, 2012, the Company issued 200,000 restricted stock awards 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, 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 for the year ended March 31, 2017 is as follows:

	Number of Shares
Unvested at March 31, 2016		6,250
Granted		—
Vested		(6,250	)
Canceled / forfeited		—
Unvested at March 31, 2017		—

Restricted stock units

During the year ended March 31, 2017, the Company issued restricted stock units for an aggregate of 1,309,656 shares of common stock to its employees and directors. These shares of common will be issued upon vesting of the restricted stock units. Vesting generally occurs (i) on the one-year anniversary of the grant date, (ii) quarterly over a three-year period, (iii) quarterly over a four-year period, (iv) over a four-year period, with 25% vesting on the one-year anniversary of the vesting commencement date and the remainder vesting ratably on a quarterly basis over the next twelve quarters, or (v) over a three-year period with 50% vesting on the two-year anniversary of the vesting commencement date and 50% vesting on the three-year anniversary of the vesting commencement date.

A summary of the Company’s restricted stock unit activity for the year ended March 31, 2017 is as follows:

	Number of Shares			Weighted Average Price
Unvested at March 31, 2016		—			—
Granted		1,309,656		$	3.59
Vested		(106,650	)	$	3.86
Canceled / forfeited		(24,892	)	$	3.21
Unvested at March 31, 2017		1,178,114		$	3.57

Stock options

During the years ended March 31, 2017 and 2016, under the 2012 Equity Incentive Plan, 1,955,016 and 2,966,778 incentive stock options were issued, respectively, at various exercise prices. The stock options generally vest on (i) the one year anniversary of the grant date, (ii) quarterly over a three year period, or (iii) 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. Stock options can also vest immediately at the grant date or vest after one full year.

The following table summarizes stock option activity for the year ended March 31, 2017:

	Options Outstanding			Weighted- Average Exercise Price		Aggregate Intrinsic Value
Outstanding at March 31, 2016		9,614,627		$	4.79	$	1,927,137
Options granted		1,955,016		$	3.79	$	—
Options canceled		(368,171	)	$	5.64	$	—
Options exercised		(245,271	)	$	2.38	$	356,616
Outstanding at March 31, 2017		10,956,201		$	4.63	$	4,876,437
Vested and Exercisable at March 31, 2017		7,054,815		$	4.64	$	4,380,611

The weighted-average remaining contractual term of stock options exercisable and outstanding at March 31, 2017 was approximately 5.89 years.

Employee Stock Purchase Plan

In June 2016, our Board of Directors adopted, and in August 2016 stockholders subsequently approved, the 2016 ESPP, consisting of 1,500,000 shares of common stock. The ESPP permits employees after five months of service to purchase common stock through payroll deductions, limited to 15 percent of each employee’s compensation up to $25,000 or 10,000 shares per employee per year. Shares under the ESPP are purchased at 85 percent of the fair market value at the lower of (i) the closing price on the first trading day of the six-month purchase period or (ii) the closing price on the last trading day of the six-month purchase period. The initial offering period commenced in September 2016. During the year ended March 31, 2017, 52,557 shares were issued under the ESPP. At March 31, 2017, there were 1,447,443 shares remaining available for the purchase under the ESPP.

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, 2017, 2016 and 2015, 353,093, 0 and 203,000 of these warrants were exercised for cash proceeds of approximately $336,000, $0 and $445,000, respectively, and 469,000, 43,796 and 8,647 of these warrants were exercised through a cashless exercise for issuance of 347,286, 32,914 and 7,600 shares of common stock, respectively.

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 the 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, 2017, 2016, and 2015, 0, 0, and 0 warrants held by consultants were exercised. As of March 31, 2017, 1,370 of these warrants are outstanding.

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.

In November 2014, in connection with a consulting 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 ended 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 $6,000 and $31,000 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, 2017:

	Warrants			Weighted-Average Exercise Price
Balance at March 31, 2016		1,046,813		$	2.29
Granted		—			—
Expired / Canceled		(3,350	)	$	1.00
Exercised		(822,093	)	$	0.98
Balance at March 31, 2017		221,370		$	7.16

The warrants outstanding at March 31, 2017 are immediately exercisable at prices between $2.28 and $7.62 per share, and have a weighted average remaining term of approximately 1.86 years.

Common stock reserved for future issuance

Common stock reserved for future issuance consisted of the following at March 31, 2017:

Common stock warrants outstanding			221,370
Common stock options outstanding under the 2008 Plan			622,192
Common stock options outstanding and reserved under the 2012 Plan			13,951,395
Restricted stock units outstanding under the 2012 Plan			1,178,114
Common stock reserved under the 2016 Employee Stock Purchase Plan			1,447,443
Total			17,420,514

Commitments and Contingencies

12 Months Ended

Mar. 31, 2017

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 facilities at 6275 Nancy Ridge Drive, San Diego, CA 92121. The lease, as amended in 2013, 2015 and 2016, consists of approximately 45,580 rentable square feet containing laboratory, clean room and office space. Monthly rental payments are currently approximately $120,000 per month with 3% annual escalators. The lease term for 14,685 of the total rentable square footage expires on December 15, 2018, with the remainder of the rentable square footage expiring on September 1, 2021, with the Company having an option to terminate this lease on or after September 1, 2019.

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.

In addition to these two leases, the Company previously leased a third facility from February 1, 2016 through January 31, 2017, consisting of 12,088 rentable square feet of office space located at 6166 Nancy Ridge Drive, San Diego, California 92121 with a monthly rent of $15,000.

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 $1,295,000, $1,088,000, and $968,000 for the years ended March 31, 2017, 2016 and 2015, 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, 2017, are as follows (in thousands):

Fiscal year ended March 31, 2018		1,596
Fiscal year ended March 31, 2019		1,464
Fiscal year ended March 31, 2020		1,072
Fiscal year ended March 31, 2021		1,104
Fiscal year ended March 31, 2022		468
Thereafter		—
Total	$	5,704

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, 2017

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. The Company began paying a minimum annual royalty of $25,000 in January 2017 for the calendar year 2017, which 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, 2017			March 31, 2016
License fees	$	148		$	148
Less accumulated amortization		(53	)		(43	)
License fees, net	$	95		$	105

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 $10,300, $9,700, and $8,500 for the years ended March 31, 2017, 2016 and 2015, respectively. At March 31, 2017, the weighted average remaining amortization period for all licenses was approximately 10 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, 2017

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, 2017 and 2016 (in thousands):

	March 31, 2017			March 31, 2016
Deferred tax assets:
Net operating loss carry forwards	$	—		$	—
Research and development credits		—			—
Depreciation and amortization		(71	)		(105	)
Accrued expenses and reserves		1,373			862
Stock compensation		6,720			5,584
Other, net		7			12
Total deferred tax assets		8,029			6,353
Valuation allowance		(8,029	)		(6,353	)
	$	—		$	—

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, 2017. 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 $1,676,000 and $2,107,000 for the years ended March 31, 2017 and 2016, respectively.

The Company had federal, state, and foreign net operating loss carryforwards of approximately $119,845,000 and $69,040,000 and $326,000, respectively, as of March 31, 2017. The federal and state net operating loss carryforwards will begin expiring in 2028, unless previously utilized. The foreign net operating loss carry forwards do not expire.

In March 2016, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Updated No. 2016-09, Compensation – Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”). ASU 2016-09 simplifies how several aspects of share-based payments are accounted for and presented in the financial statements. ASU 2016-09 is effective for public companies for annual reporting periods beginning after December 15, 2016. The Company will adopt this ASU in the quarter ended June 30, 2017. The Company has excess tax benefits for which a benefit could not be previously recognized of approximately $6,332, 000. Upon adoption, the balance of the unrecognized excess tax benefits will be reversed with the impact recorded to retained earnings including any change to the valuation allowance as a result of the adoption. Due to the full valuation allowance of the U.S. deferred tax assets, the Company does not expect any impact to the financial statements as a result of this adoption.

The Company had federal and state research tax credit carryforwards of approximately $1,793,000 and $2,076,000 at March 31, 2017, 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, 2017.

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, 2017.

The Company does not have any unrecognized tax benefits that will significantly decrease or increase within 12 months of March 31, 2017.

The Company is subject to tax in the United States, in various state jurisdictions, and in the United Kingdom. As of March 31, 2017, the Company’s tax years from inception are subject to examination by the tax authorities due to the generation of net operating losses. The Company is not currently under examination by any jurisdiction.

Concentrations	12 Months Ended
Concentrations	Mar. 31, 2017
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, 2017.

Defined Contribution Plan	12 Months Ended
Defined Contribution Plan	Mar. 31, 2017
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, 2017, 2016, and 2015 were approximately $352,000, $277,000, and $57,000, respectively.

Recent Accounting Pronouncements	12 Months Ended
Recent Accounting Pronouncements	Mar. 31, 2017
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 this update 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 this updated standard on our ongoing financial reporting. We do not have plans to adopt this standard prior to the effective date. 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 March 2016, the FASB issued ASU 2016-09, Compensation-Stock Compensation (Topic 718), which requires an entity recognize excess tax benefits and deficiencies as income tax expense or benefit, the cash flows of which should be included as operating activity in the statement of cash flows. An entity is allowed to either continue accruing compensation cost based on expected forfeitures or to begin recognizing expense as forfeitures occur. In addition, an entity may withhold the maximum statutory tax, increasing the allowable cash settlement portion of awards. The cash paid by an employer when directly withholding shares for tax purposes should be included in the financing activity section of the statement of cash flows. This new guidance is effective for us on April 1, 2017, with early adoption permitted in any interim or annual period. The requirements of ASU 2016-09 are not expected to have a significant impact on our consolidated financial statements.

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-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=66092750

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=64853466&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=64853466&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
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-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=64853466&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=68064558&loc=d3e765-108305

Reference 11: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=68064558&loc=d3e725-108305

+ Details

Quarterly Financial Data (unaudited)

12 Months Ended

Mar. 31, 2017

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, 2017
	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
Revenue	$	891		$	1,376		$	1,151		$	812
Net loss		(8,767	)		(9,442	)		(9,581	)		(10,657	)
Net loss per common share - basic and diluted		(0.09	)		(0.10	)		(0.09	)		(0.10	)
Weighted average shares used in computing net loss per common share—basic and diluted		92,391,964			93,185,400			101,174,734			104,385,617


	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

Subsequent Events	12 Months Ended
Subsequent Events	Mar. 31, 2017
Subsequent Events [Abstract]
Subsequent Events	13. Subsequent Events On April 11, 2017, the Company announced that its Board of Directors had appointed Taylor J. Crouch to serve as its Chief Executive Officer and President, with a start date on April 24, 2017. Pursuant to an offer letter between the Company and Mr. Crouch, the Company agreed to issue Mr. Crouch a Stock Option for 2,088,212 shares of Common Stock and a Performance-Based Restricted Stock Unit Award representing the right to receive up to 208,822 shares of Common Stock on or after his start date. In accordance with the terms of the offer letter, the Compensation Committee of the Company’s Board of Directors approved and issued the Stock Option and the Performance-Based Restricted Stock Unit Award on April 24, 2017.

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

12 Months Ended

Mar. 31, 2017

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

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, 2017 and 2016 (in thousands):
	Balance at March 31, 2017		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	—	$	—	$	—	$	—

	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

The following table presents the activity for liabilities measured at estimated fair value using unobservable inputs for the years ended March 31, 2017 and 2016:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

	Warrant Derivative Liability (in thousands)
Balance at March 31, 2015	$	126
Issuances	$	—
Adjustments to estimated fair value	$	17
Warrant liability removal due to settlements	$	(139	)
Balance at March 31, 2016	$	4
Issuances	$	—
Adjustments to estimated fair value	$	(4	)
Warrant liability removal due to settlements	$	—
Balance at March 31, 2017	$	—

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

The Company recognizes product revenue at the time of shipment to the customer, provided all other revenue recognition criteria have been met.

Grant revenues

Cost of 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, 2017

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, 2017 and 2016 (in thousands):
	Balance at March 31, 2017		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Unobservable Inputs (Level 3)
Warrant liability	$	—	$	—	$	—	$	—

	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

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, 2017 and 2016:

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

	Warrant Derivative Liability (in thousands)
Balance at March 31, 2015	$	126
Issuances	$	—
Adjustments to estimated fair value	$	17
Warrant liability removal due to settlements	$	(139	)
Balance at March 31, 2016	$	4
Issuances	$	—
Adjustments to estimated fair value	$	(4	)
Warrant liability removal due to settlements	$	—
Balance at March 31, 2017	$	—

Fixed Assets (Tables)

12 Months Ended

Mar. 31, 2017

Property Plant And Equipment [Abstract]

Schedule of Fixed Assets

Fixed assets consisted of the following (in thousands):

	March 31, 2017			March 31, 2016
Laboratory equipment	$	3,727		$	2,799
Construction in process		—			52
Computer software and equipment		656			488
Furniture and fixtures		319			337
Leasehold improvements		2,045			1,832
Vehicles		9			9
		6,756			5,517
Less accumulated depreciation		(2,916	)		(1,806	)
	$	3,840		$	3,711

Accrued Expenses (Tables)

12 Months Ended

Mar. 31, 2017

Payables And Accruals [Abstract]

Summary of Accrued Expenses

Accrued expenses consisted of the following (in thousands):

	March 31, 2017		March 31, 2016
Accrued compensation	$	3,318	$	2,221
Accrued legal and professional fees		572		168
Other accrued expenses		211		61
	$	4,101	$	2,450

Derivative Liability (Tables)

12 Months Ended

Mar. 31, 2017

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
Closing price per share of common stock	$	2.17
Exercise price per share	$	1.00
Expected volatility		73.35	%
Risk-free interest rate		0.59	%
Dividend yield		—
Remaining expected term of underlying securities (years)		0.96

- 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=64837297&loc=d3e41641-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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-Section 50
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64837297&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=64837297&loc=SL5624171-113959

Reference 8: 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=64837297&loc=SL5579240-113959

Reference 9: 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=64837297&loc=d3e41620-113959

Reference 10: 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, 2017

Equity [Abstract]

Schedule of Stock-based Compensation Expense

Stock-based compensation expense for all stock awards consists of the following (in thousands):

	Year Ended March 31, 2017		Year Ended March 31, 2016 (1)		Year Ended March 31, 2015
Research and development	$	1,646	$	1,248	$	1,190
General and administrative	$	5,746	$	7,308	$	5,830
Total	$	7,392	$	8,556	$	7,020

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, 2017			Year Ended March 31, 2016			Year Ended March 31, 2015
Dividend yield		—			—			—
Volatility		72.17	%		73.96	%		76.90	%
Risk-free interest rate		1.16	%		1.57	%		1.60	%
Expected life of options	6.00 years			6.00 years			6.00 years
Weighted average grant date fair value	$	2.41		$	2.52		$	4.14

Fair Value of Employee Stock Purchase Plan

The fair value of ESPP shares was estimated at the purchase period commencement date using the following weighted average assumptions:

	Year Ended March 31, 2017
Dividend yield		—
Volatility	72.89 % - 74.70 %
Risk-free interest rate	0.47 % - 0.79 %
Expected term	6 months
Grant date fair value	$	1.04 - 1.22

Summary of Company's Restricted Stock Award Activity

A summary of the Company’s restricted stock award activity for the year ended March 31, 2017 is as follows:

	Number of Shares
Unvested at March 31, 2016		6,250
Granted		—
Vested		(6,250	)
Canceled / forfeited		—
Unvested at March 31, 2017		—

Summary of Company's Restricted Stock Unit Activity

A summary of the Company’s restricted stock unit activity for the year ended March 31, 2017 is as follows:

	Number of Shares			Weighted Average Price
Unvested at March 31, 2016		—			—
Granted		1,309,656		$	3.59
Vested		(106,650	)	$	3.86
Canceled / forfeited		(24,892	)	$	3.21
Unvested at March 31, 2017		1,178,114		$	3.57

Summary of Stock Option Activity

The following table summarizes stock option activity for the year ended March 31, 2017:

	Options Outstanding			Weighted- Average Exercise Price		Aggregate Intrinsic Value
Outstanding at March 31, 2016		9,614,627		$	4.79	$	1,927,137
Options granted		1,955,016		$	3.79	$	—
Options canceled		(368,171	)	$	5.64	$	—
Options exercised		(245,271	)	$	2.38	$	356,616
Outstanding at March 31, 2017		10,956,201		$	4.63	$	4,876,437
Vested and Exercisable at March 31, 2017		7,054,815		$	4.64	$	4,380,611

Summary of Warrant Activity

The following table summarizes warrant activity for the years ended March 31, 2017:

	Warrants			Weighted-Average Exercise Price
Balance at March 31, 2016		1,046,813		$	2.29
Granted		—			—
Expired / Canceled		(3,350	)	$	1.00
Exercised		(822,093	)	$	0.98
Balance at March 31, 2017		221,370		$	7.16

Common Stock Reserved for Future Issuance

Common stock reserved for future issuance consisted of the following at March 31, 2017:

Common stock warrants outstanding			221,370
Common stock options outstanding under the 2008 Plan			622,192
Common stock options outstanding and reserved under the 2012 Plan			13,951,395
Restricted stock units outstanding under the 2012 Plan			1,178,114
Common stock reserved under the 2016 Employee Stock Purchase Plan			1,447,443
Total			17,420,514

- 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, 2017

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, 2017, are as follows (in thousands):

Fiscal year ended March 31, 2018		1,596
Fiscal year ended March 31, 2019		1,464
Fiscal year ended March 31, 2020		1,072
Fiscal year ended March 31, 2021		1,104
Fiscal year ended March 31, 2022		468
Thereafter		—
Total	$	5,704

Licensing Agreements and Research Contracts (Tables)

12 Months Ended

Mar. 31, 2017

Goodwill And Intangible Assets Disclosure [Abstract]

Schedule of Capitalized License Fees

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

	March 31, 2017			March 31, 2016
License fees	$	148		$	148
Less accumulated amortization		(53	)		(43	)
License fees, net	$	95		$	105

Income Taxes (Tables)

12 Months Ended

Mar. 31, 2017

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, 2017 and 2016 (in thousands):

	March 31, 2017			March 31, 2016
Deferred tax assets:
Net operating loss carry forwards	$	—		$	—
Research and development credits		—			—
Depreciation and amortization		(71	)		(105	)
Accrued expenses and reserves		1,373			862
Stock compensation		6,720			5,584
Other, net		7			12
Total deferred tax assets		8,029			6,353
Valuation allowance		(8,029	)		(6,353	)
	$	—		$	—

Quarterly Financial Data (unaudited) (Tables)

12 Months Ended

Mar. 31, 2017

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, 2017
	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
Revenue	$	891		$	1,376		$	1,151		$	812
Net loss		(8,767	)		(9,442	)		(9,581	)		(10,657	)
Net loss per common share - basic and diluted		(0.09	)		(0.10	)		(0.09	)		(0.10	)
Weighted average shares used in computing net loss per common share—basic and diluted		92,391,964			93,185,400			101,174,734			104,385,617


	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

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, 2017	Mar. 31, 2016	Mar. 31, 2015
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit			$ (199,317,000)	$ (160,870,000)
Cash flow from operations			29,185,000	29,368,000	$ 19,601,000
Foreign currency translation adjustment			(11,000)	0	0
Restricted cash			127,000	79,000
Inventory of raw materials, net of reserves			467,000	206,000
Inventory of work-in-process, net of reserves			83,000	15,000
Inventory of finished goods, net of reserves			$ 0	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
Warrants expiration date			Mar. 31, 2017
Deferred revenue			$ 582,000	1,110,000
Revenue related to research contract			1,022,000	486,000	134,000
Cost of revenues			956,000	0	0
Revenue recognized under grants			41,000	191,000	123,000
Dilutive effect			$ 0	$ 0	$ 0
Common stock equivalents excluded from computing diluted net loss per share			12.4	10.7	8.6
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			$ 0	$ 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			41,000	43,000	49,000
Research and Development Services [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Deferred revenue			640,000	1,110,000
Research and Development Services Two [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue related to research contract					69,000
Research and Development Services Three [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue related to research contract					41,000
Research and Development Services Four [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue related to research contract			117,000	352,000
Research and Development Services Five [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue related to research contract			835,000	80,000
Research and Development Services Six [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue related to research contract			32,000	$ 50,000	$ 18,000
Research and Development Services Seven [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue related to research contract			34,000
Research and Development Services Eight [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue related to research contract			$ 3,000
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, 2017	Mar. 31, 2016	Mar. 31, 2015
Fair Value, Measurements, Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrant liability	$ 0	$ 4
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	0	4	$ 126
Significant Other Unobservable Inputs (Level 3) [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrant liability	$ 0	$ 4

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, 2017	Mar. 31, 2016
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Warrant Derivative Liability, Beginning balance	$ 4	$ 126
Issuances	0	0
Adjustments to estimated fair value	(4)	17
Warrant liability removal due to settlements	0	(139)
Warrant Derivative Liability, Ending balance	$ 0	$ 4

Fixed Assets - Schedule of Fixed Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Mar. 31, 2016
Property Plant And Equipment [Abstract]
Laboratory equipment	$ 3,727	$ 2,799
Construction in process	0	52
Computer software and equipment	656	488
Furniture and fixtures	319	337
Leasehold improvements	2,045	1,832
Vehicles	9	9
Fixed assets, gross	6,756	5,517
Less accumulated depreciation	(2,916)	(1,806)
Fixed assets, net	$ 3,840	$ 3,711

Accrued Expenses - Summary of Accrued Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Mar. 31, 2016
Payables And Accruals [Abstract]
Accrued compensation	$ 3,318	$ 2,221
Accrued legal and professional fees	572	168
Other accrued expenses	211	61
Accrued expenses	$ 4,101	$ 2,450

Derivative Liability - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	Nov. 30, 2014	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Mar. 31, 2012	Mar. 31, 2011
Derivative [Line Items]
Warrants issued						22,847,182	22,847,182
Warrants maturity term	5 years					5 years	5 years
Estimated fair value of the outstanding warrant liabilities		$ 0	$ 4,000
Change in fair value of warrant liabilities		$ (4,000)	$ 17,000	$ (196,000)	$ (196,000)
Exercised derivative liabilities		0	43,796
Warrants expired		3,350
Warrants [Member]
Derivative [Line Items]
Estimated fair value of the outstanding warrant liabilities		$ 0	$ 4,000

- 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]	12 Months Ended
	Mar. 31, 2016 $ / shares
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Closing price per share of common stock	$ 2.17
Exercise price per share	$ 1.00
Expected volatility	73.35%
Risk-free interest rate	0.59%
Dividend yield	0.00%
Remaining expected term of underlying securities (years)	11 months 16 days

Stockholders' Equity - Schedule of Stock-based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 7,392	$ 8,556	$ 7,020
Research and development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	1,646	1,248	1,190
General and administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 5,746	$ 7,308	$ 5,830

Stockholders' Equity - Stock-based Compensation Expense and Valuation Information - Additional Information (Detail)	12 Months Ended
	Mar. 31, 2017 USD ($)
Class Of Stock [Line Items]
Total unrecognized compensation cost related to unvested stock option grants	$ 10,271,000
Stock options [Member]
Class Of Stock [Line Items]
Total unrecognized compensation cost related, weighted average period	2 years 2 months 12 days
Restricted stock units (RSUs) [Member]
Class Of Stock [Line Items]
Total unrecognized compensation cost related, weighted average period	2 years 10 months 10 days
Unrecognized stock-based compensation expense	$ 3,557,000
Restricted stock [Member]
Class Of Stock [Line Items]
Unrecognized stock-based compensation expense	$ 0

Stockholders' Equity - Fair Value of Employee Stock Options (Detail) - $ / shares	1 Months Ended	12 Months Ended
	Nov. 30, 2014	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Dividend yield		0.00%	0.00%	0.00%
Volatility	73.40%	72.17%	73.96%	76.90%
Risk-free interest rate	1.21%	1.16%	1.57%	1.60%
Expected life of options		6 years	6 years	6 years
Weighted average grant date fair value		$ 2.41	$ 2.52	$ 4.14

Stockholders' Equity - Fair Value of Employee Stock Purchase Plan (Detail) - $ / shares	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividend yield	0.00%	0.00%	0.00%
Expected term	6 years	6 years	6 years
Grant date fair value	$ 2.41	$ 2.52	$ 4.14
2016 Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividend yield	0.00%
Volatility, minimum	72.89%
Volatility, maximum	74.70%
Risk-free interest rate, minimum	0.47%
Risk-free interest rate, maximum	0.79%
Expected term	6 months
2016 Employee Stock Purchase Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Grant date fair value	$ 1.04
2016 Employee Stock Purchase Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Grant date fair value	$ 1.22

Stockholders' Equity - Preferred Stock and Common Stock - Additional Information (Detail) - USD ($)			1 Months Ended	12 Months Ended			28 Months Ended
	Oct. 20, 2016	Jun. 18, 2015	Nov. 30, 2013	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2017	Apr. 24, 2017	Oct. 25, 2016	Aug. 31, 2015	Feb. 27, 2015	Aug. 31, 2013	Jul. 17, 2013	Jan. 31, 2012	May 31, 2008
Class Of Stock [Line Items]
Preferred stock, shares authorized				25,000,000			25,000,000
Preferred stock, shares outstanding				0			0
Issuance of common stock from stock options exercises, net, Shares				245,271	116,001	205,033
Issuance of common stock				104,551,466	92,391,989		104,551,466
Common stock, par value				$ 0.001	$ 0.001		$ 0.001
Issuance of common stock from warrant exercises, net, Shares				700,379	32,914	210,600
Warrants exercised				822,903	43,796	211,647
Stock option exercised				245,271	116,001	205,684
Equity Distribution Agreement [Member]
Class Of Stock [Line Items]
Value of shares sold under equity distribution agreement				$ 0	$ 0	$ 16,100,000
Issuance of common stock from stock options exercises, net, Shares				0	0	2,197,768
Equity Offering Sales Agreement [Member]
Class Of Stock [Line Items]
Value of shares sold under equity distribution agreement				$ 4,600,000	$ 0	$ 6,200,000	$ 10,800,000
Issuance of common stock from stock options exercises, net, Shares				997,181	0	1,000,000
Issuance of common stock				1,997,181			1,997,181
Additional common stocks under shelf registration				$ 21,900,000			$ 21,900,000
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]
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 \| 2015 Underwriting Agreement [Member]
Class Of Stock [Line Items]
Issuance of common stock from stock options exercises, net, Shares		10,838,750
Common stock, par value		$ 0.001
Offering price per share		$ 4.25
Gross proceeds from sale of common stock shares		$ 43,100,000
Secondary Offering \| 2016 Underwriting Agreement [Member]
Class Of Stock [Line Items]
Offering price per share	$ 2.75
Gross proceeds from sale of common stock shares	$ 25,700,000
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
Over Allotment Option [Member] \| 2016 Underwriting Agreement [Member]
Class Of Stock [Line Items]
Issuance of common stock									10,065,000
Sale of stock price per share net of fees	$ 2.585
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				3,617,386			3,617,386			17,553,986
Termination period of Equity Incentive Plan				10 years
Inducement Award Agreements [Member] \| Subsequent Event [Member]
Class Of Stock [Line Items]
Common shares authorized to be issued								2,297,034

Stockholders' Equity - Restricted Stock Awards and Restricted Stock Units - Additional Information (Detail) - shares	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2012
Class Of Stock [Line Items]
Restricted stock awards issued to member of senior management	200,000
Restricted stock units (RSUs) [Member]
Class Of Stock [Line Items]
Restricted stock awards vested during the period	106,650	250,000	255,000
Restricted stock surrendered		129,900	137,816
Restricted stock awards granted	1,309,656
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
Granted, Number of Shares	1,309,656
Restricted stock [Member]
Class Of Stock [Line Items]
Restricted stock awards vested during the period	6,250
Restricted stock awards granted	0
Common stock returned by holders		2,500
Granted, Number of Shares	0
Stock options [Member]
Class Of Stock [Line Items]
Restricted stock awards granted	1,309,656
Period for vesting schedule over start date	4 years
Granted, Number of Shares	1,309,656
Awards granted remainder vesting period ratably on a quarterly basis	36 months
Award vesting percentage on the two-year anniversary	50.00%
Award vesting percentage on the three-year anniversary	50.00%
Stock options [Member] \| 2012 Plan [Member]
Class Of Stock [Line Items]
Award vesting conditions	stock options generally vest on (i) the one year anniversary of the grant date, (ii) quarterly over a three year period, or (iii) 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
Stock options [Member] \| Yearly Vesting [Member] \| 2012 Plan [Member]
Class Of Stock [Line Items]
Award vesting conditions	0
Award vesting percentage	25.00%
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
Granted, Number of Shares				950,000
Non-Executive Employees [Member] \| Restricted stock units (RSUs) [Member]
Class Of Stock [Line Items]
Restricted stock awards granted				130,000
Granted, Number of Shares				130,000
Consultants [Member] \| Restricted stock units (RSUs) [Member]
Class Of Stock [Line Items]
Restricted stock awards granted				100,000
Percentage of vesting schedule				100.00%
Period for vesting schedule over start date				6 months
Granted, Number of Shares				100,000

Stockholders' Equity - Summary of Company's Restricted Stock Award Activity (Detail) - Restricted stock [Member]	12 Months Ended
	Mar. 31, 2017 shares
Class Of Stock [Line Items]
Beginning balance, Unvested, Number of Shares	6,250
Granted, Number of Shares	0
Vested, Number of Shares	(6,250)
Canceled / forfeited, Number of Shares	0
Ending balance, Unvested, Number of Shares	0

Stockholders' Equity - Summary of Company's Restricted Stock Unit Activity (Detail) - Restricted stock units (RSUs) [Member] - $ / shares	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Class Of Stock [Line Items]
Beginning balance, Unvested, Number of Shares	0
Granted, Number of Shares	1,309,656
Vested, Number of Shares	(106,650)	(250,000)	(255,000)
Canceled / forfeited, Number of Shares	(24,892)
Ending balance, Unvested, Number of Shares	1,178,114	0
Beginning balance, Unvested, Weighted Average Price	$ 0
Granted, Weighted Average Price	3.59
Vested, Weighted Average Price	3.86
Canceled / forfeited, Weighted Average Price	3.21
Ending balance, Unvested, Weighted Average Price	$ 3.57	$ 0

Stockholders' Equity - Stock Options and Employee Stock Purchase Plan - Additional Information (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Class Of Stock [Line Items]
Issuances of common stock from stock option exercises, Shares	245,271	116,001	205,684
Weighted-average remaining contractual term of stock options exercisable	5 years 10 months 21 days
Weighted-average remaining contractual term of stock options outstanding	5 years 10 months 21 days
Number of common stock shares approved under ESPP	17,420,514
Expected life of options	6 years	6 years	6 years
Shares issued under ESPP	52,557,000
2012 Plan [Member]
Class Of Stock [Line Items]
Issuances of common stock from stock option exercises, Shares	1,955,016	2,966,778
Remaining options vest	36 months
2016 Employee Stock Purchase Plan [Member]
Class Of Stock [Line Items]
Number of common stock shares approved under ESPP	1,500,000
Employee subscription rate	15.00%
Compensation amount per employee	$ 25,000
Number of shares per employee	10,000
Fair market value at discount	85.00%
Purchase period	6 months
Initial offering period	2016-09
Description of plan	0
Expected life of options	6 months
Shares available for issuance	1,447,443
Stock options [Member] \| 2012 Plan [Member]
Class Of Stock [Line Items]
Award vesting conditions	stock options generally vest on (i) the one year anniversary of the grant date, (ii) quarterly over a three year period, or (iii) 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
Stock options [Member] \| 2016 Employee Stock Purchase Plan [Member]
Class Of Stock [Line Items]
Number of common stock shares approved under ESPP	1,447,443,000

Stockholders' Equity - Summary of Stock Option Activity (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Options Outstanding, Beginning balance	9,614,627
Granted, Options Outstanding	1,955,016
Canceled, Options Outstanding	(368,171)
Exercised, Options Outstanding	(245,271)	(116,001)	(205,684)
Options Outstanding, Ending balance	10,956,201	9,614,627
Vested and Exercisable, Options Outstanding	7,054,815
Weighted-Average Exercise Price, Options Beginning balance	$ 4.79
Options granted, Weighted-Average Exercise Price	3.79
Options canceled, Weighted-Average Exercise Price	5.64
Options exercised, Weighted-Average Exercise Price	2.38
Weighted-Average Exercise Price, Options Ending balance	4.63	$ 4.79
Vested and Exercisable, Weighted-Average Exercise Price	$ 4.64
Aggregate Intrinsic Value, Options	$ 4,876,437	$ 1,927,137
Options Exercised, Aggregate Intrinsic Value	356,616
Vested and Exercisable, Aggregate Intrinsic Value	$ 4,380,611

Stockholders' Equity - Warrants - Additional Information (Detail) - USD ($)		1 Months Ended		12 Months Ended
	Dec. 31, 2014	Nov. 30, 2014	Sep. 30, 2014	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2015	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
Warrants to purchase common stock		145,000		1,370					650,000
Interest expense				$ 0	$ 0		$ 1,000
Warrants maturity term		5 years								5 years	5 years
Warrants issued			50,000
Warrants earned, service period		17 months
Number of warrant shares vested upon satisfaction of specific performance metrics				95,000
Volatility		73.40%		72.17%	73.96%		76.90%
Risk-free interest rate		1.21%		1.16%	1.57%		1.60%
Weighted-average remaining contractual term of options exercisable				5 years 10 months 21 days
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					$ 6,000		$ 31,000
Minimum [Member]
Class Of Stock [Line Items]
Warrants exercisable price, per share				$ 2.28
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				353,093	0		203,000
Cash proceeds from warrant exercises				$ 336,000	$ 0		$ 445,000
Number of warrant exercised through cashless				469,000	43,796		8,647
Cashless exercise in exchange for issuance of common stock				347,286	32,914		7,600
Warrants exercisable price, per share		$ 6.84
Estimated fair value of warrants		$ 74,000
Weighted-average remaining contractual term of options exercisable				1 year 10 months 10 days
Warrants [Member] \| Consultants [Member]
Class Of Stock [Line Items]
Number of warrants exercised				0	0	0
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, 2017	Mar. 31, 2016	Mar. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options Outstanding, Beginning balance	9,614,627
Granted, Options Outstanding	1,955,016
Expired / Canceled, Options Outstanding	(368,171)
Exercised, Options Outstanding	(245,271)	(116,001)	(205,684)
Options Outstanding, Ending balance	10,956,201	9,614,627
Weighted-Average Exercise Price, Options Beginning balance	$ 4.79
Granted, Weighted-Average Exercise Price	3.79
Expired / Canceled, Weighted-Average Exercise Price	5.64
Exercised, Weighted-Average Exercise Price	2.38
Weighted-Average Exercise Price, Options Ending balance	$ 4.63	$ 4.79
Warrants [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options Outstanding, Beginning balance	1,046,813
Granted, Options Outstanding	0
Expired / Canceled, Options Outstanding	(3,350)
Exercised, Options Outstanding	(822,093)
Options Outstanding, Ending balance	221,370	1,046,813
Weighted-Average Exercise Price, Options Beginning balance	$ 2.29
Granted, Weighted-Average Exercise Price	0
Expired / Canceled, Weighted-Average Exercise Price	1.00
Exercised, Weighted-Average Exercise Price	0.98
Weighted-Average Exercise Price, Options Ending balance	$ 7.16	$ 2.29

Stockholders' Equity - Common Stock Reserved for Future Issuance (Detail)	Mar. 31, 2017 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance	17,420,514
2016 Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance	1,500,000
Warrants [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance	221,370
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	13,951,395
Stock options [Member] \| 2016 Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance	1,447,443,000
Restricted stock units (RSUs) [Member] \| Equity Incentive Plan 2012 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance	1,178,114,000

Commitments and Contingencies - Additional Information (Detail)			3 Months Ended	12 Months Ended			57 Months Ended
	Dec. 28, 2015 USD ($) ft²	Jan. 09, 2015 USD ($) ft²	Mar. 31, 2017 ft² Lease	Mar. 31, 2017 USD ($) ft² Lease	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Mar. 31, 2017 USD ($) Lease
Commitments And Contingencies Disclosure [Abstract]
Number of non-cancelable leases \| Lease			3	3			3
Rent expense per month				$ 120,000
Base rent escalators		3.00%	3.00%	3.00%			3.00%
Office space under lease agreement \| ft²			14,685	45,580
Lease expiration date			Dec. 15, 2018	Sep. 01, 2021
Lease option termination description				option to terminate this lease on or after September 1, 2019
Area of leased office space \| ft²	12,088	5,803
Lease term		36 months
Lease rental period start date	Feb. 01, 2016	Feb. 01, 2015
Lease rental period end date	Jan. 31, 2017	Jan. 31, 2018
Base rent under the lease	$ 15,000	$ 12,000
Leasehold improvements					$ 374,000	$ 144,000	$ 518,000
Rent expense				$ 1,295,000	$ 1,088,000	$ 968,000

Commitments and Contingencies - Future Minimum Rental Payments Required under Operating Leases that have Initial or Remaining Non-Cancelable Lease Terms in Excess of One Year (Detail) $ in Thousands	Mar. 31, 2017 USD ($)
Commitments And Contingencies Disclosure [Abstract]
Fiscal year ended March 31, 2018	$ 1,596
Fiscal year ended March 31, 2019	1,464
Fiscal year ended March 31, 2020	1,072
Fiscal year ended March 31, 2021	1,104
Fiscal year ended March 31, 2022	468
Thereafter	0
Total	$ 5,704

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, 2018	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					$ 10,300	$ 9,700	$ 8,500
Weighted average remaining amortization period for all licenses					10 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%
Minimum annual royalty payment, start date					2017-01
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, 2017	Mar. 31, 2016
Finite-Lived Intangible Assets [Line Items]
License fees	$ 148	$ 148
Less accumulated amortization	(53)	(43)
License fees, net	$ 95	$ 105

Income Taxes - Summary of Net Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Mar. 31, 2016
Deferred tax assets:
Net operating loss carry forwards	$ 0	$ 0
Research and development credits	0	0
Depreciation and amortization	(71)	(105)
Accrued expenses and reserves	1,373	862
Stock compensation	6,720	5,584
Other, net	7	12
Total deferred tax assets	8,029	6,353
Valuation allowance	(8,029)	(6,353)
Deferred tax assets net	$ 0	$ 0

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Operating Loss Carryforwards [Line Items]
Unrecognized tax benefits	$ 0	$ 0
Increase (decrease) in valuation allowance	1,676,000	2,107,000
Federal net operating loss carryforwards	119,845,000
State net operating loss carryforwards	69,040,000
Foreign net operating loss carryforwards	$ 326,000
Federal and state net operating loss carryforwards expiring year	2028
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	1,793,000
State [Member]
Operating Loss Carryforwards [Line Items]
Research tax credit carryforwards	$ 2,076,000
Accounting Standards Update 2016-09 [Member]
Operating Loss Carryforwards [Line Items]
Unrecognized excess tax benefits		$ 6,332,000

Quarterly Financial Data (unaudited) - Schedule of Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 812	$ 1,151	$ 1,376	$ 891	$ 548	$ 328	$ 301	$ 306	$ 4,230	$ 1,483	$ 571
Net loss	$ (10,657)	$ (9,581)	$ (9,442)	$ (8,767)	$ (8,372)	$ (10,455)	$ (11,257)	$ (8,491)	$ (38,447)	$ (38,575)	$ (30,082)
Net loss per common share - basic and diluted	$ (0.10)	$ (0.09)	$ (0.10)	$ (0.09)	$ (0.09)	$ (0.11)	$ (0.12)	$ (0.10)	$ (0.39)	$ (0.43)	$ (0.38)
Weighted average shares used in computing net loss per common share—basic and diluted	104,385,617	101,174,734	93,185,400	92,391,964	92,402,668	92,396,358	92,385,150	82,993,966	97,763,032	90,057,356	79,650,087

Subsequent Events - Additional Information (Detail) - shares	Apr. 11, 2017	Mar. 31, 2017	Mar. 31, 2016
Subsequent Event [Line Items]
Common stock, shares issued		104,551,466	92,391,989
Subsequent Event [Member] \| Common Stock [Member] \| Chief Executive Officer and President [Member]
Subsequent Event [Line Items]
Stock options issued	2,088,212
Subsequent Event [Member] \| Performance Based Restricted Stock Unit Awards [Member] \| Chief Executive Officer and President [Member]
Subsequent Event [Line Items]
Common stock, shares issued	208,822

Defined Contribution Plan - Additional Information (Details) - USD ($)	12 Months Ended
	Mar. 31, 2017	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	$ 352,000	$ 277,000	$ 57,000