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Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Mar. 31, 2020	May 29, 2020
Document And Entity Information
Entity Registrant Name	REPLIMUNE GROUP, INC.
Entity Central Index Key	0001737953
Document Type	10-K
Document Period End Date	Mar. 31, 2020
Amendment Flag	false
Current Fiscal Year End Date	--03-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Public Float	$ 178.0
Entity Small Business	true
Entity Shell Company	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Common Stock, Shares Outstanding		36,784,130
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Current assets:
Cash and cash equivalents	$ 59,500	$ 25,704
Short-term investments	109,055	109,107
Research and development incentives receivable	2,962	2,474
Prepaid expenses and other current assets	2,734	3,696
Total current assets	174,251	140,981
Property, plant and equipment, net	6,860	12,159
Restricted cash	1,636	1,186
Right-to-use asset - operating leases	4,425
Right-to-use asset - financing leases	46,925
Total assets	234,097	154,326
Current liabilities:
Accounts payable	3,434	7,084
Accrued expenses and other current liabilities	5,156	2,801
Operating lease liabilities, current	873
Financing lease liabilities, current	2,411
Total current liabilities	11,874	9,885
Deferred rent, net of current portion		24
Financing obligation		6,561
Long term debt, net of debt discount	9,801
Operating lease liabilities, non-current	3,737
Finance lease liabilities, non-current	24,967
Total liabilities	50,379	16,470
Commitments and contingencies (Note 12)
Stockholders' Equity:
Common stock, $0.001 par value; 150,000,000 shares authorized as of March 31, 2020 and 2019: 36,668,743 and 31,656,950 shares issued and outstanding as of March 31, 2020 and 2019, respectively	37	32
Additional paid-in capital	296,961	198,645
Accumulated deficit	(112,298)	(59,766)
Accumulated other comprehensive loss	(982)	(1,055)
Total stockholders' equity	183,718	137,856
Total liabilities and stockholders' equity	$ 234,097	$ 154,326

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 31, 2020	Mar. 31, 2019
CONSOLIDATED BALANCE SHEETS
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized	150,000,000	150,000,000
Common stock, issued	36,668,743	31,656,950
Common stock, outstanding	36,668,743	31,656,950

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Operating expenses:
Research and development	$ 38,761	$ 22,173	$ 13,516
General and administrative	17,437	8,773	5,713
Total operating expenses	56,198	30,946	19,229
Loss from operations	(56,198)	(30,946)	(19,229)
Other income (expense):
Research and development incentives	3,084	2,528	2,267
Investment income	2,424	2,585	288
Interest expense on finance lease liability	(1,185)
Interest expense on debt obligations	(734)
Change in fair value of warrant liability		(5,452)	(972)
Other income (expense)	(16)	451	(2,056)
Total other income (expense), net	3,573	112	(473)
Net loss attributable to common stockholders	$ (52,625)	$ (30,834)	$ (19,702)
Net loss per share attributable to common shareholders, basic and diluted (in dollars per share)	$ (1.54)	$ (1.33)	$ (3.96)
Weighted average common shares outstanding-basic and diluted (in shares)	34,261,548	23,198,400	4,978,539

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS
Net loss	$ (52,625)	$ (30,834)	$ (19,702)
Other comprehensive loss:
Foreign currency translation gain (loss)	(236)	(897)	2,376
Net unrealized gain (loss) on short-term investments, net of tax	309	80	(65)
Comprehensive loss	$ (52,552)	$ (31,651)	$ (17,391)

- Definition

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

+ References + Details

CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Convertible preferred stock	Common A stock Common stock	Series B convertible Preferred Stock	Common stock ATM sales	Common stock Follow-on public offering	Common stock	Additional paid-in capital ATM sales	Additional paid-in capital Follow-on public offering	Additional paid-in capital Prefunded common stock warrants	Additional paid-in capital	Accumulated deficit Follow-on public offering	Accumulated deficit	Accumulated other comprehensive loss	ATM sales	Follow-on public offering	Prefunded common stock warrants	Total
Balance at Mar. 31, 2017	$ 31,609					$ 5				$ 259		$ (9,230)	$ (2,549)				$ (11,515)
Balance (in shares) at Mar. 31, 2017	1,064,553					4,973,439
Increase (decrease) in Stockholders' Equity
Issuance of series convertible preferred stock, net of issuance costs			$ 54,752
Issuance of series convertible preferred stock, net of issuance costs (in shares)			861,415
Foreign currency translation adjustment													2,376				2,376
Unrealized gain (loss) on short-term investments													(65)				(65)
Issuance of stock (in shares)		26,258
Stock options in exchange for consulting services										26							26
Stock options in exchange for consulting services (in shares)						7,788
Stock-based compensation expense										812							812
Net loss												(19,702)					(19,702)
Balance at Mar. 31, 2018	$ 86,361					$ 5				1,097		(28,932)	(238)				(28,068)
Balance (in shares) at Mar. 31, 2018	1,925,968					5,007,485
Increase (decrease) in Stockholders' Equity
Foreign currency translation adjustment													(897)				(897)
Unrealized gain (loss) on short-term investments													80				80
Exercise of stock options						$ 1				205							206
Exercise of stock options (in shares)						110,427
Conversion of convertible preferred stock into common stock upon closing of initial public offering	$ (86,361)					$ 19				86,342							86,361
Conversion of convertible preferred stock into common stock upon closing of initial public offering (in shares)	(1,925,968)					19,157,360
Conversion of convertible preferred stock warrants into common stock warrants										7,094							7,094
Repurchase of class A common stock upon closing of initial public offering (in shares)						(26,258)
Issuance of stock					$ 7			$ 101,177							$ 101,184
Issuance of stock (in shares)					7,407,936
Stock-based compensation expense										2,730							2,730
Net loss												(30,834)					(30,834)
Balance at Mar. 31, 2019						$ 32				198,645		(59,766)	(1,055)				137,856
Balance (in shares) at Mar. 31, 2019						31,656,950
Increase (decrease) in Stockholders' Equity
Foreign currency translation adjustment													(236)				(236)
Unrealized gain (loss) on short-term investments													309				309
Exercise of stock options										551							$ 551
Exercise of stock options (in shares)						207,673											207,673
Impact of adoption of ASC 842											$ 93				93
Issuance of stock					$ 5		$ 4,431	$ 57,448	$ 28,145					$ 4,431	$ 57,453	$ 28,145
Issuance of stock (in shares)				287,559	4,516,561									287,559
Stock-based compensation expense										7,741							$ 7,741
Net loss												(52,625)					(52,625)
Balance at Mar. 31, 2020						$ 37				$ 296,961		$ (112,298)	$ (982)				$ 183,718
Balance (in shares) at Mar. 31, 2020						36,668,743

CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Prefunded common stock warrants
Issuance costs and underwriter fees	$ 1,797
Common stock
Issuance costs and underwriter fees	$ 4,017	$ 9,935
Series B convertible Preferred Stock
Issuance costs and underwriter fees			$ 198

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities:
Net loss	$ (52,625)	$ (30,834)	$ (19,702)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	7,741	2,730	812
Depreciation and amortization	533	148	109
Change in fair value of warrant liability		5,452	972
Stock options in exchange for consulting services			26
Net amortization (accretion) of premium and discount on short-term investments	(945)	(1,715)	(123)
Noncash rent expense		93
Noncash interest expense	156
Changes in operating assets and liabilities:
Research and development incentives receivable	(628)	(255)	(767)
Prepaid expenses and other current assets	933	(801)	(305)
Operating lease, right-of-use-asset	588
Finance lease, right-of-use-asset	1,274
Long term prepaid rent	(15,787)
Accounts payable	(3,821)	120	1,596
Accrued expenses and other current liabilities	2,479	(292)	1,393
Operating lease liabilities	(450)
Deferred rent		(24)	(25)
Net cash used in operating activities	(60,552)	(25,378)	(16,014)
Cash flows from investing activities:
Purchases of property, plant and equipment	(6,540)	(2,600)	(136)
Purchase of short-term investments	(149,682)	(189,931)	(52,463)
Proceed from sales and maturities of short-term investments	150,989	126,587	8,553
Net cash provided by (used in) investing activities	(5,233)	(65,944)	(44,046)
Cash flows from financing activities:
Proceeds from issuance of series B convertible preferred stock, net of issuance costs			54,752
Proceeds from issuance of common stock in initial public offering, net of underwriting fees and discounts		103,341
Proceeds from issuance of common stock in follow-on public offering, net of underwriting fees and discounts	57,453
Proceeds from issuance of prefunded warrants to purchase common stock, net of underwriting fees and discounts	28,145
Proceeds from issuance of common stock through ATM sales	4,431
Proceeds from long-term debt	10,000
Exercise of stock options	551	206
Payment of issuance costs	(355)	(2,157)
Principal payment of finance lease obligation	(59)
Net cash provided by financing activities	100,166	101,390	54,752
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(135)	(839)	2,297
Net increase (decrease) in cash, cash equivalents and restricted cash	34,246	9,229	(3,011)
Cash, cash equivalents and restricted cash at beginning of year	26,890	17,661	20,672
Cash, cash equivalents and restricted cash at end of year	61,136	26,890	17,661
Supplemental disclosure of cash flow information
Cash paid for interest	578
Supplemental disclosure of non-cash investing and financing activities:
Net unrealized gain (loss) on short-term investments	309	80	$ (65)
Purchases of property and equipment included in accounts payable	209	5,047
Conversion of convertible preferred stock into common stock		7,094
Conversion of convertible preferred stock warrants into common stock warrants		86,361
Amounts capitalized under built-to-suit lease transaction		$ 4,292
Lease assets obtained in exchange for new financing lease liabilities	48,224
Lease assets obtained in exchange for new operating lease liabilities	5,152
Adjustment for non-cash lease termination	$ 117

Nature of the business	12 Months Ended
Nature of the business	Mar. 31, 2020
Nature of the business
Nature of the business	1. Nature of the business Replimune Group, Inc. (the “Company”) is a clinical‑stage biotechnology company focused on the development of oncolytic immunotherapies to treat cancer. Replimune Limited (“Replimune UK”) was incorporated in 2015 under the laws of England, and was the sole shareholder of Replimune, Inc. (“Replimune US”), a Delaware corporation. On July 5, 2017, Replimune Group, Inc., a Delaware corporation, was incorporated and on July 10, 2017 the shareholders of Replimune UK effected a share‑for‑share exchange pursuant to which they exchanged their outstanding shares in Replimune UK for shares in Replimune Group, Inc., on a one‑for‑one basis. In addition, the holders of warrants and stock options to purchase Replimune UK capital stock canceled their warrants to purchase shares of series seed preferred stock and stock options in Replimune UK and were issued replacement warrants to purchase shares of series seed preferred stock and stock options to acquire Replimune Group, Inc. capital stock on a one‑for‑one basis. These transactions are collectively referred to as the reorganization. Upon completion of the reorganization, the historical consolidated financial statements of Replimune UK became the historical consolidated financial statements of Replimune Group, Inc. because the reorganization was accounted for similar to a reorganization of entities under common control due to the high degree of common ownership of Replimune UK and Replimune Group, Inc. and lack of economic substance to the transaction. The Company concluded that the reorganization resulted in no change in the material rights and preferences of each respective class of equity interests and no change in the fair value of each respective class of equity interests before and after the reorganization. On December 8, 2017, Replimune UK transferred all outstanding shares of its wholly owned subsidiary, Replimune US to Replimune Group, Inc. Replimune Group. Inc., a Delaware corporation, is the sole shareholder of Replimune UK, Replimune US and Replimune Securities Corporation, a Massachusetts corporation that was incorporated in November 2017. The Company is subject to risks and uncertainties common to early‑stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations and the ability to secure additional capital to fund operations. Product candidates currently under development will require significant additional research and development efforts, including preclinical and clinical testing and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance and reporting capabilities. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales. Forward stock split On July 9, 2018, the Company effected a 1‑for‑9.94688 forward stock split of its issued and outstanding shares of common stock and a proportional adjustment to the existing conversion ratios for each series of the Company’s Preferred Stock (see Note 8). Accordingly, all share and per share amounts for all periods presented in the accompanying consolidated financial statements and notes thereto have been adjusted retroactively, where applicable, to reflect this forward stock split and adjustment of the preferred stock conversion ratios. Further, on July 9, 2018, the Company’s authorized shares of common stock were increased to 27,314,288. Accordingly, the authorized shares of common stock presented in the accompanying consolidated financial statements and notes thereto have been adjusted retroactively, where applicable, to reflect the newly authorized shares of common stock. Initial public offering On July 24, 2018, the Company completed an initial public offering (“IPO”) of its common stock and issued and sold 6,700,000 shares of common stock at a public offering price of $15.00 per share, resulting in net proceeds of $93,465 after deducting underwriting discounts and commissions but before deducting offering costs of $2,157. Upon closing of the IPO, the Company’s outstanding convertible preferred stock automatically converted into shares of common stock (see Note 8). Upon conversion of the convertible preferred stock, the Company reclassified the carrying value of the convertible preferred stock to common stock and additional paid-in capital. The warrant to purchase shares of the Company’s series seed convertible preferred stock was converted into a warrant to purchase shares of the Company’s common stock upon the closing of the IPO. As a result, the warrant liability was remeasured a final time on the closing date of the IPO and reclassified to stockholders’ equity (deficit). Additionally, the Company repurchased 26,258 shares of class A common stock at a price equal to its par value upon the closing of the IPO. On July 30, 2018, the Company issued and sold an additional 707,936 shares of its common stock at the IPO price of $15.00 per share pursuant to the underwriters’ partial exercise of their option to purchase additional shares of common stock, resulting in additional net proceeds of $9,876 after deducting discounts and commissions and other offering expenses. Also, in connection with the completion of its IPO on July 24, 2018, the Company filed an amended and restated certificate of incorporation with the Secretary of State of the State of Delaware to authorize the issuance of up to 150,000,000 shares of common stock, par value $0.001 per share, and 10,000,000 shares of undesignated preferred stock, par value $0.001 per share. Basis of presentation The accompanying consolidated financial statements have been prepared on the basis of continuity of operations, realization of assets and the satisfaction of liabilities and commitments in the ordinary course of business. The Company has incurred recurring losses since its inception, including net losses of $52,625, $30,834 and $19,702 for the years ended March 31, 2020, 2019 and 2018, respectively. In addition, as of March 31, 2020, the Company had an accumulated deficit of $112,298 . The Company expects to continue to generate operating losses for the foreseeable future. As of June 3, 2020, the issuance date of these consolidated financial statements, the Company expects that its cash and cash equivalents and short-term investments will be sufficient to fund its operating expenses and capital expenditure requirements through at least 12 months from the issuance of the consolidated financial statements. The future viability of the Company beyond that point is dependent on its ability to raise additional capital to finance its operations. If the Company is unable to obtain funding it could be forced to delay, reduce or eliminate some or all of its research and development programs, product portfolio expansion or commercialization efforts, which could adversely affect its business prospects, or it may be unable to continue operations. Although management continues to pursue these plans, there is no assurance that the Company will be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations, if at all. Impact of the COVID-19 coronavirus In December 2019, a novel strain of coronavirus, which causes the disease known as COVID-19, was reported to have surfaced in Wuhan, China. Since then, COVID-19 coronavirus has spread globally. In March 2020, the World Health Organization declared the COVID-19 outbreak a pandemic and the U.S. government imposed travel restrictions on travel between the United States, Europe and certain other countries. The impact of this pandemic has been, and will likely continue to be, extensive in many aspects of society, which has resulted, and will likely continue to result, in significant disruptions to the global economy as well as businesses and capital markets around the world. In response to public health directives and orders and to help minimize the risk of the virus to employees, the Company has taken precautionary measures, including implementing work-from-home policies for certain employees. The impact of the virus, including work-from-home policies, may negatively impact productivity, disrupt the Company’s business, and delay its preclinical research and clinical trial activities and its development program timelines, the magnitude of which will depend, in part, on the length and severity of the restrictions and other limitations on the Company’s ability to conduct its business in the ordinary course. Other impacts to the Company’s business may include temporary closures of its suppliers and disruptions or restrictions on its employees’ ability to travel. Any prolonged material disruption to the Company’s employees or suppliers could adversely impact the Company’s preclinical research and clinical trial activities, financial condition and results of operations, including its ability to obtain financing.

Summary of significant accounting policies

12 Months Ended

Mar. 31, 2020

Summary of significant accounting policies

Summary of significant accounting policies

2. Summary of significant accounting policies

Principles of consolidation

The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America, or GAAP, and include the accounts of the Company and its wholly owned subsidiaries, Replimune UK, Replimune US and Replimune Securities Corporation, after elimination of all intercompany accounts and transactions. The consolidated financial statements reflect the capital as if Replimune Group, Inc. had been in existence for all periods presented.

Use of estimates

The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the accrual for research and development expenses and the valuation of common stock and stock‑based awards. The Company bases its estimates on historical experience, known trends and other market‑specific or other relevant factors that it believes to be reasonable under the circumstances.

The full extent to which the COVID-19 pandemic will directly or indirectly impact our business, results of operations and financial condition, including, expenses, research and development costs and employee-related amounts, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain it or treat COVID-19. We have made estimates of the impact of COVID-19 within our financial statements and there may be changes to those estimates in future periods.

Estimates are periodically reviewed in light of reasonable changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates or assumptions.

Foreign currency and currency translation

The functional currency for the Company’s wholly owned foreign subsidiary, Replimune UK, is the British pound. Assets and liabilities of Replimune UK are translated into United States dollars at the exchange rate in effect on the balance sheet date. Revenues and expenses are translated at the average exchange rate in effect during the period. Unrealized translation gains and losses are recorded as a cumulative translation adjustment, which is included in the consolidated statements of convertible preferred stock and stockholders’ equity (deficit) as a component of accumulated other comprehensive loss. Adjustments that arise from exchange rate changes on transactions denominated in a currency other than the local currency are included in other income (expense), net in the consolidated statements of operations as incurred.

Concentrations of credit risk and of significant suppliers

Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents as well as short‑term investments. The Company deposits its cash in financial institutions in amounts that may exceed federally insured limits, and has not experienced any losses on such accounts and does not believe it is exposed to any unusual credit risk beyond the normal credit risk associated with commercial banking relationships.

The Company relies, and expects to continue to rely, on a small number of vendors to manufacture supplies and raw materials for its development programs. These programs could be adversely affected by a significant interruption in these manufacturing services or the availability of raw materials.

Cash and cash equivalents

The Company considers all highly liquid investments with original maturities of three months or less at date of purchase to be cash equivalents. Cash equivalents consisted of money market funds at March 31, 2020. Cash equivalents consisted of money market funds, U.S. Treasury bonds, and U.S. Government Agency Bonds at March 31, 2019. As of March 31, 2020 and 2019, cash equivalents totaled $36,712 and $10,664, respectively.

Restricted cash

The Company maintains certain minimum balances in segregated bank accounts in connection with a letter of credit for the benefit of the landlords in connection with an operating lease. As of March 31, 2020 and 2019, restricted cash consisted of $1,636 and $1,186, respectively, held for the benefit of the landlords in connection with a financing lease and an operating lease. These amounts have been classified as non-current assets on the Company’s consolidated balance sheets.

Short‑term investments

The Company’s short‑term debt security investments are classified as available‑for‑sale and are carried at fair value, with the unrealized gains and losses reported as a component of accumulated other comprehensive income (loss) in stockholders’ equity (deficit). Realized gains and losses and declines in value determined to be other than temporary are based on the specific identification method and are included as a component of other income (expense), net in the consolidated statements of operations.

The Company evaluates its short-term debt security investments with unrealized losses for other-than-temporary impairment. When assessing short-term debt security investments for other-than-temporary declines in value, the Company considers such factors as, among other things, how significant the decline in value is as a percentage of the original cost, how long the market value of the investment has been less than its original cost, the Company’s ability and intent to retain the short-term debt security investment for a period of time sufficient to allow for any anticipated recovery in fair value and market conditions in general. If any adjustment to fair value reflects a decline in the value of the short-term debt security investment that the Company considers to be “other than temporary,” the Company reduces the short-term debt security investment to fair value through a charge to the consolidated statements of operations. No such adjustments were necessary during the periods presented.

The Company’s short‑term debt security investments as of March 31, 2020 and 2019 had maturities of less than one year.

Deferred offering costs

The Company capitalizes certain legal, professional accounting and other third‑party fees that are directly associated with in‑process equity financings as deferred offering costs until such financings are consummated. After consummation of the equity financing, these costs are recorded in stockholders’ equity (deficit) as a reduction of proceeds generated as a result of the offering. Should an in‑process equity financing be abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the consolidated statements of operations. As of March 31, 2019, the Company recorded $2,157 of deferred offering costs in stockholders’ equity (deficit) as a reduction of proceeds generated as a result of the IPO. The Company did not record any deferred offering costs as of March 31, 2020.

Property, plant and equipment

Property, plant and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation and amortization expense is recognized using the straight‑line method over the estimated useful lives of the respective assets as follows:


		Estimated Useful life
Office equipment		5 years
Computer equipment		3 years
Plant, plant and laboratory equipment		5 years
Leasehold improvements		Lesser of lease term or 10 years

Costs for capital assets not yet placed into service are capitalized as construction‑in‑progress and depreciated in accordance with the above guidelines once placed into service. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is included in loss from operations. Expenditures for repairs and maintenance are charged to expense as incurred.

Impairment of long‑lived assets

Long‑lived assets consist of property, plant and equipment. Long‑lived assets to be held and used are tested for recoverability whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. Factors that the Company considers in deciding when to perform an impairment review include significant underperformance of the business in relation to expectations, significant negative industry or economic trends and significant changes or planned changes in the use of the assets. If an impairment review is performed to evaluate a long‑lived asset group for recoverability, the Company compares forecasts of undiscounted cash flows expected to result from the use and eventual disposition of the long‑lived asset group to its carrying value. An impairment loss would be recognized when estimated undiscounted future cash flows expected to result from the use of an asset group are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset group over its fair value, determined based on discounted cash flows. To date, the Company has not recorded any impairment losses on long‑lived assets.

Fair value measurements

Certain assets and liabilities of the Company are carried at fair value under GAAP. Fair value 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. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable:

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

Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data.

Level 3—Unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

The Company’s short‑term investments, cash equivalents and warrant liability are carried at fair value, determined according to the fair value hierarchy described above (see Note 3). The carrying values of research and development incentives receivable, other current assets, accounts payable and accrued expenses and other current liabilities approximate their fair values due to the short‑term nature of these assets and liabilities. The carrying value of the Company's outstanding loan agreement with Hercules approximates its fair value at March 31, 2020 because the debt bears interest at a variable market rate and the Company's credit risk has not materially changed since the inception of the agreement.

Warrant liability

Upon the closing of the IPO, the warrants to purchase shares of the Company’s series seed convertible preferred stock were converted into warrants to purchase shares of the Company’s common stock. As a result, the warrant liability was remeasured a final time on the closing date of the IPO and reclassified to stockholders’ equity (deficit).

Prior to the IPO, the Company classified warrants to purchase shares of series seed preferred stock (see Note 8) as a liability on its consolidated balance sheets as these warrants to purchase shares of series seed preferred stock were free-standing financial instruments that could require the Company to transfer assets upon exercise. The warrant liability was initially recorded at fair value upon the date of the warrants’ issuance and was subsequently remeasured to fair value at each reporting date. Changes in the fair value of the warrant liability were recognized as a component of total other income (expense), net in the consolidated statements of operations.

The Company utilized the Black-Scholes option-pricing model, which incorporated assumptions and estimates, to value the warrant liability. The Company assessed these assumptions and estimates on a quarterly basis as additional information impacting assumptions was obtained. Estimates and assumptions impacting the fair value measurement included the expected stock price volatility, the expected term of the warrant, the risk-free interest rate for a period that approximated the expected term of the warrant, and the Company’s expected dividend yield (see Note 3).

Debt issuance costs

Debt issuance costs consist of payments made to secure commitments under certain debt financing arrangements. These amounts are recognized as interest expense over the period of the financing arrangement using the effective interest method. If the financing arrangement is canceled or forfeited, or if the utility of the arrangement to the Company is otherwise compromised, these costs are recognized as interest expense immediately. The Company's consolidated financial statements present debt issuance costs related to a recognized debt liability as a direct reduction from the carrying amount of that debt liability.

Segment information

The Company manages its operations as a single operating segment for the purposes of assessing performance and making operating decisions. The Company’s current focus is on developing oncolytic immunotherapies for the treatment of cancer.

Research and development costs

Research and development costs are expensed as incurred. Research and development expenses consist of costs incurred in performing research and development activities, including salaries, stock‑based compensation and benefits, facilities costs and laboratory supplies, depreciation and external costs of outside vendors engaged to conduct preclinical development, clinical development activities and clinical trials as well as to manufacture clinical trial materials. Non‑refundable prepayments for goods or services that will be used or rendered for future research and development activities are deferred and capitalized. Such amounts are recognized as an expense as the goods are delivered or the related services are performed, or until it is no longer expected that the goods will be delivered or the services rendered. Upfront payments for materials and supplies acquired for particular research and development activities that have no alternative future use in other research and development projects or otherwise, and therefore have no separate economic value, are expensed as research and development costs at the time the costs are incurred.

Research contract costs and accruals

The Company has entered into various research and development‑related contracts with companies both inside and outside of the United States. These agreements are generally cancelable, and related costs are recorded as research and development expenses as incurred. The Company records accruals for estimated ongoing research costs. When evaluating the adequacy of the accrued liabilities, the Company analyzes progress of the studies or clinical trials, including the phase or completion of events, invoices received and contracted costs. Significant judgments and estimates are made in determining the accrued balances at the end of any reporting period. Actual results could differ from the Company’s estimates. The Company’s historical accrual estimates have not been materially different from the actual costs.

Patent costs

All patent‑related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred are classified as general and administrative expenses.

Stock‑based compensation

The Company measures all stock‑based awards granted to employees, consultants, and non-employees and directors based on the fair value on the date of the grant and recognizes compensation expense for those awards over the requisite service period, which is generally the vesting period of the respective award. The fair value of each stock option grant is estimated on the date of grant using the Black‑Scholes option‑pricing model, which requires inputs based on certain subjective assumptions, including the expected stock price volatility, the expected term of the option, the risk‑free interest rate for a period that approximates the expected term of the option, and the Company’s expected dividend yield (see Note 9). Forfeitures are accounted for as they occur. To date, the Company has issued stock‑based awards with only service‑based vesting conditions and records the expense for these awards using the straight‑line method.

The Company classifies stock‑based compensation expense in its consolidated statements of operations in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified.

Research and development incentives and receivable

The Company, through its subsidiary in the United Kingdom, receives reimbursements of certain research and development expenditures as part of a United Kingdom government’s research and development tax reliefs program. Under the program, a percentage of qualifying research and development expenses incurred by the Company’s subsidiary in the United Kingdom are reimbursed up to 14.5%.

Management has assessed the Company’s research and development activities and expenditures to determine which activities and expenditures are likely to be eligible under the research and development incentive program described above. At each period end, management estimates the reimbursement available to the Company based on available information at the time.

The Company recognizes income from the research and development incentives when the relevant expenditure has been incurred, the associated conditions have been satisfied and there is reasonable assurance that the reimbursement will be received. The Company records these research and development incentives as other income. The research and development incentives receivable represents an amount due in connection with the above program. The Company recorded other income from research and development incentives of $3,084, $2,528 and $2,267 during the years ended March 31, 2020, 2019 and 2018, respectively, in the consolidated statements of operations and a research and development incentives receivable of $2,962 and $2,474 as of March 31, 2020 and 2019, respectively, on the consolidated balance sheets.

Comprehensive loss

Comprehensive loss includes net loss as well as other changes in stockholders’ equity (deficit) that result from transactions and economic events other than those with stockholders. For the year ended March 31, 2020, comprehensive loss included $(236) of foreign currency translation adjustments and $309 of unrealized gains on short-term investments, net of tax. For the year ended March 31, 2019, comprehensive loss included $(897) of foreign currency translation adjustments and $80 of unrealized gains on short-term investments, net of tax. For the year ended March 31, 2018, comprehensive loss included $2,376 of foreign currency translation adjustments and $(65) of unrealized losses on short-term investments, net of tax.

Income taxes

The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in the Company’s tax returns. Deferred tax assets and liabilities are determined on the basis of the differences between the consolidated financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies.

The Company accounts for uncertainty in income taxes recognized in the consolidated financial statements by applying a two‑step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more‑likely‑than‑not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the consolidated financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, that are considered appropriate as well as the related net interest and penalties.

Net income (loss) per share

The Company follows the two‑class method when computing net income (loss) per share as the Company has issued shares that meet the definition of participating securities. The two‑class method determines net income (loss) per share for each class of common and participating securities according to dividends declared or accumulated and participation rights in undistributed earnings. The two‑class method requires income available to common stockholders for the period to be allocated between common and participating securities based upon their respective rights to receive dividends as if all income for the period had been distributed.

Basic net income (loss) per share attributable to common stockholders is computed by dividing the net income (loss) attributable to common stockholders by the weighted average number of shares of common stock outstanding for the period. Diluted net income (loss) attributable to common stockholders is computed by adjusting net income (loss) attributable to common stockholders to reallocate undistributed earnings based on the potential impact of dilutive securities. Diluted net income (loss) per share attributable to common stockholders is computed by dividing the diluted net income (loss) attributable to common stockholders by the weighted average number of shares of common stock outstanding for the period, including potential dilutive common shares assuming the dilutive effect of common stock equivalents.

The Company’s convertible preferred stock contractually entitled the holders of such shares to participate in dividends but contractually did not require the holders of such shares to participate in losses of the Company. Accordingly, in periods in which the Company reported a net loss, such losses were not allocated to such participating securities. In periods in which the Company reports a net loss attributable to common stockholders, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive.

Recently adopted accounting pronouncements

In June 2018, the FASB issued Accounting Standards Updates (“ASU”) No. 2018-07, Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting (“ASU 2018-07”). ASU 2018-17 expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. ASU 2018-17 also clarifies that Topic 718 does not apply to share-based payments used to effectively provide (1) financing to the issuer or (2) awards granted in conjunction with selling goods or services to customers as part of a contract accounted for under Revenue from Contracts with Customers (Topic 606). The guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within that fiscal year. Early adoption is permitted. The Company adopted ASU 2018-17 on April 1, 2019. The adoption of ASU 2018- 17 did not have a material impact on the Company’s consolidated financial statements.

In July 2017, the FASB issued ASU No. 2017-11, Earnings Per Share (Topic 260), Distinguishing Liabilities from Equity (Topic 480), Derivatives and Hedging (Topic 815) I. Accounting for Certain Financial Instruments with Down Round Features II. Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception (“ASU 2017-11”). Part I applies to entities that issue financial instruments such as warrants, convertible debt or convertible preferred stock that contain down-round features. Part II replaces the indefinite deferral for certain mandatorily redeemable noncontrolling interests and mandatorily redeemable financial instruments of nonpublic entities contained within Accounting Standards Codification (“ASC”) Topic 480 with a scope exception and does not impact the accounting for these mandatorily redeemable instruments. ASU 2017-11 is required to be adopted for annual periods beginning after December 15, 2018, including interim periods within those fiscal years. The Company adopted ASU 2017-11 on April 1, 2019. The adoption of ASU 2017-11 did not have a material impact on the Company’s consolidated financial statements.

In February 2016, the FASB issued ASU No. 2016-02 (“ASU 2016-02”), Leases (Topic 842), which supersedes FASB Topic 840, Leases (Topic 840) and provides principles for the recognition, measurement, presentation and disclosure of leases for both lessees and lessors. The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease, respectively. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of classification. Leases with a term of 12 months or less will be accounted for similar to existing guidance for operating leases. In January 2018, the FASB issued ASU 2018-01, Leases (Topic 842) Land Easement Practical Expedient for Transition to Topic 842, which amends ASU 2016-02 to provide entities an optional transition practical expedient to not evaluate under Topic 842 existing or expired land easements that were not previously accounted for as leases under the current leases guidance in Topic 842. An entity that elects this practical expedient should evaluate new or modified land easements under Topic 842 beginning at the date that the entity adopts Topic 842. In July 2018, the FASB also issued ASU 2018-11, Leases (Topic 842): Targeted Improvements, which provides an optional transition method that allows entities to elect to apply the standard prospectively at its effective date, versus recasting the prior periods presented.

The Company adopted ASU 2016-02, as amended, on April 1, 2019, which supersedes the current leasing guidance and upon adoption, requires lessees to recognize right-of-use assets and lease liabilities on the balance sheet for all leases with terms longer than 12 months. Leases are classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. Upon the adoption of the guidance, operating leases are capitalized on the balance sheet at the present value of lease payments. The balance sheet amount recorded for existing leases at the date of adoption of ASU 2016-02 was calculated using the applicable incremental borrowing rate at the date of adoption.

The Company elected the available package of practical expedients, which allows the Company to not reassess previous accounting conclusions around whether arrangements are or contain leases, the classification of leases, and the treatment of initial direct costs. The Company also made an accounting policy election to utilize the short-term lease exemption, whereby leases with a term of 12 months or less will not follow the recognition and measurement requirements of the new standard. Upon adoption, the Company recognized total right-of-use assets of $789, with corresponding liabilities of $837 on the consolidated balance sheets. Additionally, the Company derecognized $11,514 of construction in progress assets and $6,561 of financing obligations and recorded long term prepaid rent of $5,006 on the consolidated balance sheet (see Note 12).

The following table summarizes the financial impact on the Company’s consolidated balance sheet upon the adoption of ASU 2016-02 and the cumulative effect adjustment on April 1, 2019:


	March 31, 2019		Adjustments		April 1, 2019
Property, plant, and equipment, net	$	12,159	$	(11,514)	$	645
Right-to-use asset	$	—	$	789	$	789
Long term prepaid rent	$	—	$	5,006	$	5,006
Lease liabilities, current	$	—	$	388	$	388
Lease liabilities, non-current	$	—	$	449	$	449
Accrued expenses	$	2,801	$	(24)	$	2,777
Deferred rent, net of current portion	$	24	$	(24)	$	—
Financing obligation	$	6,561	$	(6,561)	$	—
Accumulated deficit	$	(59,766)	$	93	$	(59,673)

Recently issued accounting pronouncements

In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820), Disclosure Framework- Changes to the Disclosure Requirements for Fair Value Measurement (“ASU 2018-13”). The amendments in this ASU require certain existing disclosure requirements in Topic 820 to be modified or removed, and certain new disclosure requirements to be added to the Topic. In addition, this ASU allows entities to exercise more discretion when considering fair value measurement disclosures. ASU 2018-13 will be effective for the Company beginning April 1, 2020 with early adoption permitted. The adoption of ASU 2018-13 is not expected to have a material impact on the Company's consolidated financial statements.

In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326). The standard changes how entities will measure credit losses for most financial assets and certain other instruments that are not measured at fair value through net income. Financial assets measured at amortized cost will be presented at the net amount expected to be collected by using an allowance for credit losses. In April 2019, the FASB issued ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments, which clarifies and corrects certain unintended applications of the guidance contained in each of the amended Topics. Additionally, in May 2019, the FASB issued ASU No. 2019-05, Financial Instruments-Credit Losses (Topic 326), which provides an option to irrevocably elect to measure certain individual financial assets at fair value instead of amortized cost. The standard is effective for fiscal years and interim periods beginning after December 15, 2019. Early adoption is permitted for all periods beginning after December 15, 2018. The adoption of ASU 2018-13 is not expected to have a material impact on the Company's consolidated financial statements.

In November 2018, the FASB issued ASU No. 2018-18, Collaborative Arrangements (Topic 808): Clarifying the Interaction between Topic 808 and Topic 606 (“ASU2018-18”), which clarifies that certain transactions between collaborative arrangement participants should be accounted for as revenue under Topic 606 when the collaborative arrangement participant is a customer in the context of a unit of account. In those situations, all the guidance in Topic 606 should be applied, including recognition, measurement, presentation, and disclosure requirements. The standard adds unit-of-account guidance in Topic 808 to align with the guidance in Topic 606 (that is, a distinct good or service) when an entity is assessing whether the collaborative arrangement or a part of the arrangement is within the scope of Topic 606, and requires that in a transaction with a collaborative arrangement participant that is not directly related to sales to third parties, presenting the transaction together with revenue recognized under Topic 606 is precluded if the collaborative arrangement participant is not a customer. The standard is effective for interim and annual periods beginning after December 15, 2019, with early adoption permitted, including adoption in any interim period for public business entities for periods in which financial statements have not been issued. Amendments in the standard should be applied retrospectively to the date of initial application of Topic 606, but entities may elect to apply the amendments in this Update retrospectively either to all contracts or only to contracts that are not completed at the date of initial application of Topic 606, and should disclose the election. An entity may also elect to apply the practical expedient for contract modifications that is permitted for entities using the modified retrospective transition method in Topic 606. The adoption of ASU 2018-13 is not expected to have a material impact on the Company's consolidated financial statements.

Fair value of financial assets and liabilities

12 Months Ended

Mar. 31, 2020

Fair value of financial assets and liabilities

Fair value of financial assets and liabilities

3. Fair value of financial assets and liabilities

The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis:


	Fair Value Measurements
	as of March 31, 2020 Using:
	Level 1		Level 2		Level 3		Total
Assets
Money market funds	$	—	$	36,712	$	—	$	36,712
Commercial paper		—		21,884		—		21,884
US Treasury bonds		—		35,810		—		35,810
US Government Agency bonds		—		15,295		—		15,295
Corporate debt securities		—		36,066		—		36,066
	$	—	$	145,767	$	—	$	145,767


	Fair Value Measurements
	as of March 31, 2019 Using:
	Level 1		Level 2		Level 3		Total
Assets
Money market funds	$	—	$	2,676	$	—	$	2,676
Commercial paper		—		46,687		—		46,687
US Government Agency bonds		—		20,884		—		20,884
US Treasury bonds		—		41,057		—		41,057
Corporate debt securities		—		8,467		—		8,467
	$	—	$	119,771	$	—	$	119,771

During the years ended March 31, 2020 and 2019, there were no transfers between levels.

Valuation of cash equivalents and short‑term investments

Money market funds, commercial paper, U.S. Treasury bonds, U.S. Government Agency bonds and corporate debt securities were valued by the Company using quoted prices in active markets for similar securities, which represent a Level 2 measurement within the fair value hierarchy. Cash equivalents consisted of money market funds at March 31, 2020. Cash equivalents consisted of money market funds, U.S. Treasury bonds, and U.S. Government Agency Bonds at March 31, 2019.

Valuation of warrant liability

The warrant liability is related to the warrants to purchase shares of series seed preferred stock (see Note 8). The fair value of the warrant liability was determined based on significant inputs not observable in the market, which represents a Level 3 measurement within the fair value hierarchy. Upon the closing of the IPO in July 2018, the warrant to purchase shares of the Company’s series seed convertible preferred stock was converted into a warrant to purchase shares of the Company’s common stock. As a result, the warrant liability was remeasured a final time on the closing date of the IPO and reclassified to stockholders’ equity (deficit).

The Company used the Black‑Scholes option‑pricing model, which incorporated assumptions and estimates, to value the warrant liability. Key estimates and assumptions impacting the fair value measurement include (i) the expected term of the warrants, (ii) the risk‑free interest rate, (iii) the expected dividend yield, (iv) expected volatility of the price of the underlying series seed preferred stock and (v) the fair value of the series seed preferred stock on the valuation date. The Company estimated the fair value per share of the underlying series seed preferred stock based, in part, on the results of third‑party valuations and additional factors deemed relevant. The risk‑free interest rate was determined by reference to the U.S. Treasury yield curve for time periods approximately equal to the remaining contractual term of the warrants. The Company estimated a 0% expected dividend yield based on the fact that the Company has never paid or declared dividends and does not intend to do so in the foreseeable future. Prior to July 2018, the Company was a private company and accordingly, lacked company‑specific historical and implied volatility information of its stock, the expected stock volatility was based on the historical volatility of publicly traded peer companies for a term equal to the remaining expected term of the warrants.

Based on the terms and conditions of the warrant, upon closing of the Company’s IPO in July 2018, the warrant to purchase shares of the Company’s series seed convertible preferred stock was converted into a warrant to purchase shares of the Company’s common stock. On that date, the Company remeasured the warrant liability to fair value and reclassified the total carrying value to additional paid-in capital. The Company performed the final remeasurement of the warrant liability using the IPO price of $15.00 per share and recorded the change in fair value as a component of total other income (expense), net in the consolidated statement of operations.

The following assumptions were used to measure the fair market value of the warrant liability upon the conversion date:


		Year Ended
		March 31, 2019
Risk-free interest rate		2.81	%
Expected term (in years)		7.2
Expected volatility		64.4	%
Expected dividend yield		0	%
Fair value of series seed preferred stock	$	15.00

The following table presents a roll forward of the warrant liability:


	Warrant
	Liability
Balance at March 31, 2018	$	1,642
Change in fair value		5,452
Conversion of convertible preferred stock warrant into common stock warrant		(7,094)
Balance at March 31, 2019	$	—

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Short-term investments

12 Months Ended

Mar. 31, 2020

Short-term investments

Short-term investments

4. Short‑term investments

Short‑term investments by investment type consisted of the following:


	March 31, 2020
			Gross		Gross
	Amortized		unrealized		unrealized
	cost		gains		losses		Fair value
Commercial paper	$	21,818	$	66	$	—	$	21,884
US Government agency bonds		15,217		78		—		15,295
US Treasury bonds		35,590		220		—		35,810
Corporate debt securities		36,107		24		(65)		36,066
	$	108,732	$	388	$	(65)	$	109,055


	March 31, 2019
			Gross		Gross
	Amortized		unrealized		unrealized
	cost		gains		losses		Fair value
Commercial paper	$	46,687	$	2	$	(2)	$	46,687
US Government agency bonds		15,889		4		—		15,893
US Treasury bonds		38,047		13		—		38,060
Corporate debt securities		8,469		—		(2)		8,467
	$	109,092	$	19	$	(4)	$	109,107

Property, plant and equipment, net

12 Months Ended

Mar. 31, 2020

Property, plant and equipment, net

Property, plant and equipment, net

5. Property, plant and equipment, net

Property, plant and equipment, net consisted of the following:


	March 31,
	2020		2019
Construction in progress	$	1,217	$	124
Plant and laboratory equipment		3,669		584
Leasehold improvements		532		154
Computer equipment		1,658		138
Office equipment		721		49
Build-to-suit lease asset		—		11,514
		7,797		12,563
Less: Accumulated depreciation and amortization		(937)		(404)
	$	6,860	$	12,159

Depreciation and amortization expense was $533, $148 and $109 for the years ended March 31, 2020, 2019 and 2018, respectively, and recorded within research and development and general and administrative expenses in the consolidated statement of operations.

Build-to-suit lease asset, as of March 31, 2019, included $11,514 capitalized in connection with the Company’s build-to-suit lease accounting. Upon transition to ASC 842, the Company determined that it did not control the build-to-suit lease asset and the arrangement has been accounted for under ASC 842 guidance. Upon the adoption of ASC 842, the Company derecognized $11,514 of construction in progress and $6,561 of financing obligations and recorded long term prepaid rent of $5,006 on the consolidated balance sheet (see Note 12).

Accrued expenses and other current liabilities

12 Months Ended

Mar. 31, 2020

Accrued expenses and other current liabilities

Accrued expenses and other current liabilities

6. Accrued expenses and other current liabilities

Accrued expenses and other current liabilities consisted of the following:


	March 31,
	2020		2019
Accrued researched and development costs	$	2,009	$	530
Accrued compensation and benefits costs		2,065		1,510
Accrued professional fees		779		464
Deferred rent		—		24
Other		303		273
	$	5,156	$	2,801

Long-term debt

12 Months Ended

Mar. 31, 2020

Long-term debt

Long-term debt

7. Long-term debt

Long-term debt consisted of the following:


	March 31,
	2020

Principal amount of long-term debt	$	10,000
Unamortized debt discount		(199)
Long-term debt, net of discount	$	9,801

Hercules Loan Agreement

On August 8, 2019, (the “Closing Date”) the Company and certain of its affiliates entered into a Loan and Security Agreement (the “Hercules Loan Agreement”) with Hercules Capital, Inc. (“Hercules”) pursuant to which Hercules agreed to make available to the Company a secured term loan facility in the amount of $30,000 (the “Term Loan Facility”), subject to certain terms and conditions. The Company borrowed $10,000 under the Hercules Loan Agreement in one advance as a single tranche Term Loan on the Closing Date upon which the Company paid a $225 facility charge and incurred $130 in additional closing and legal fees. The Company may borrow the unused $20,000 available under the Term Loan Facility in two separate advances. The second advance of up to $10,000 may be borrowed between January 1, 2020 and December 15, 2020 and the third advance of up to $10,000 may be borrowed between July 1, 2020 and June 30, 2021.

Advances under the Term Loan Facility bear interest at a rate per annum equal to the greater of either (i) the prime rate as reported in The Wall Street Journal plus 2.75%, or (ii) 8.75%. The Hercules Loan Agreement includes covenants, limitations, and events of default customary for similar facilities. The term of the Hercules Loan Agreement is four years, ending August 1, 2023.

Interest is payable on a monthly basis until March 1, 2022 (the “Amortization Date”). After the Amortization Date, payments shall consist of equal monthly installments of principal and interest payable until the secured obligations are repaid in full.

At any time the Company may prepay the principal of any advance pursuant to the terms of the Term Loan Facility subject to a prepayment charge equal to: 3.0%, if such advance is prepaid within the first twelve months following the Closing Date, 2.0%, if such advance is prepaid after twelve months but prior to twenty four months following the Closing Date, and 1.0%, if such advance is prepaid anytime thereafter. The Company will also pay a charge equal to the product of 4.95% and the aggregate amount of any advance made pursuant to the terms of the Term Loan Facility.

The Term Loan Facility is secured by substantially all of the Company’s assets, but excluding its intellectual property, and subject to certain exceptions and exclusions.

The Hercules Loan Agreement contains customary covenants for transactions of this type and other covenants agreed to by the parties, including, among others, (i) the provision of delivery of annual and quarterly financial statements and insurance policies and restrictions on incurring debt, granting liens, making acquisitions, making loans, paying dividends, dissolving, and entering into leases and asset sales. The Hercules Loan Agreement also provides for customary events of default, including, among others, events of default relating to failure to make payment, bankruptcy, breach of covenants, breaches of representations and warranties, change of control, judgment and material adverse effects.

In connection with entering into the Hercules Loan Agreement the Company paid Hercules $355 of upfront fees, including closing costs and legal fees associated with entering into the agreement, which were recorded as a debt discount. The debt discount is reflected as a reduction of the carrying value of long-term debt on the Company’s consolidated balance sheet and is being amortized to interest expense over the term of the loan using the effective interest method.

The Company recognized aggregate interest expense under the Hercules Loan Agreement of $734 during the year ended March 31, 2020, which included non-cash interest expense of $60 and $96 related to the accretion of the debt discount and the final payment. As of March 31, 2020, the unamortized debt discount was $199. The Company’s annual effective interest rate of the Hercules Loan Agreement was approximately 10.1% for the period from August 8, 2019 to March 31, 2020.

There were no principal payments due or paid under the Hercules Loan Agreement during the year ended March 31, 2020.

Future payments of long-term debt, including interest, as of March 31, 2020 are as follows (fiscal years):


Future long-term debt payments:
2021	$	—
2022		527
2023		6,558
2024		2,915
Total debt payments	$	10,000

The table of future payments of long-term debt excludes the end of term charge of $495 which is due upon the maturity of the loan.

Stockholders' Equity	12 Months Ended
Stockholders' Equity	Mar. 31, 2020
Stockholders' Equity
Stockholders' Equity	8. Stockholders’ Equity Common stock As of March 31, 2020 and 2019, the Company’s certificate of incorporation, as amended and restated, authorized the Company to issue up to 150,000,000 shares of common stock, par value $0.001 per share. As of March 31, 2020 and 2019, the Company had reserved 10,449,033 and 6,873,744 shares of common stock for the exercise of outstanding stock options, the number of shares remaining available for grant under the Company’s 2018 Omnibus Incentive Compensation Plan and the Company’s Employee Stock Purchase Plan (see Note 9) and the exercise of the outstanding warrants to purchase shares of common, respectively. Undesignated preferred stock As of March 31, 2020, the Company’s certificate of incorporation, as amended and restated, authorized the Company to issue up to 10,000,000 shares of undesignated preferred stock, par value $0.001 per share. There were no undesignated preferred shares issued or outstanding as of March 31, 2020. Convertible preferred stock The Company has issued series seed convertible preferred stock (the “series seed preferred stock”), series A convertible preferred stock (the “series A preferred stock”) and series B convertible preferred stock (the “series B preferred stock”). The series seed preferred stock, series A preferred stock and series B preferred stock are collectively referred to as the “preferred stock.” In connection with the closing of the IPO, the preferred stock converted into 19,157,360 shares of common stock on a 1:9.94688 basis. There was no preferred stock outstanding as of March 31, 2020 and 2019. Preferred stock warrants In connection with the issuance of the series seed preferred stock, the Company issued to the holders of the series seed preferred stock warrants for the purchase of 50,000 shares of series seed preferred stock, which became fully vested and exercisable in the year of issuance. The warrants to purchase shares of series seed preferred stock were issued at an exercise price of $10.00 per share and expire on the earlier of September 16, 2025 or a qualified change of control event. The issuance date fair value of the warrants to purchase shares of series seed preferred stock was $391 and was recorded as a liability with a corresponding reduction in the carrying value of the series seed preferred stock. The Company did not recognize any losses for the change in fair value of warrant liability within total other income (expense), net in the consolidated statements of operations for the years ended March 31, 2020, related to the change in fair value of the warrant liability. The Company recognized a loss of $(5,452) and $(972), in change in fair value of warrant liability within total other income (expense), net in the consolidated statements of operations for the year ended March 31, 2019 and 2018, respectively, related to the change in fair value of the warrant liability. Upon the closing of the Company’s IPO in July 2018, all outstanding convertible preferred stock was converted into common stock and the series seed preferred stock warrants became exercisable for 497,344 shares of common stock instead of series seed preferred stock. As a result, the warrant liability was remeasured a final time on the closing date of the IPO and reclassified to stockholders’ equity. ATM program In August 2019, the Company entered into a Sales Agreement (the “Sales Agreement”) with SVB Leerink LLC (the “Agent”), pursuant to which the Company may sell, from time to time, at its option, up to an aggregate amount of $75,000 of shares of the Company’s common stock, $0.001 par value per share (the “Shares”), through the Agent, as the Company’s sales agent. Any Shares to be offered and sold under the Sales Agreement will be issued and sold (i) by methods deemed to be an “at the market offering” (“ATM”), as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended or in negotiated transactions, if authorized by the Company, and (ii) pursuant to, and only upon the effectiveness of, a registration statement on Form S- 3 filed by the Company with the Securities and Exchange Commission on August 8, 2019 for an offering of up to $250,000 of various securities, including shares of the Company’s common stock, preferred stock, debt securities, warrants and/or units for sale to the public in one or more public offerings. Subject to the terms of the Sales Agreement, the Agent will use commercially reasonable efforts to sell the Shares from time to time, based upon the Company’s instructions (including any price, time or size limits or other customary parameters or conditions the Company may impose). The Company will pay the Agent a commission of 3.0% of the gross proceeds from the sale of the Shares, if any. During the year ended March 31, 2020, the Company has issued and sold 287,559 shares of common stock for gross proceeds of $4,568 less offering fees of $137 for net proceeds of $4,431 under the ATM program. Equity offerings In November 2019, the Company entered into an Underwriting Agreement (the “Underwriting Agreement”) with J.P. Morgan Securities LLC and SVB Leerink LLC, as representatives of the several underwriters named therein (the “Underwriters”), relating to the issuance and sale of an aggregate of (a) 3,678,031 shares of the Company’s common stock (the “Shares”), and (b) pre-funded warrants to purchase 2,200,000 shares of the Company’s common stock (the “Pre-Funded Warrants”) to the Underwriters (the “Offering”). The Shares were sold to the purchasers at the public offering price of $13.61 per share. The Pre-Funded Warrants were sold at a public offering price of $13.6099 per Pre-Funded Warrant, which represents the per share public offering price for the Company’s common stock less a $0.0001 per share exercise price for each such Pre-Funded Warrant. Pursuant to the Underwriting Agreement, the Company also granted the Underwriters a 30-day option to purchase up to 881,704 additional shares of its common stock. In December 2019, the Underwriters partially exercised their purchase option and the Company issued and sold an additional 838,530 shares of its common stock. The Company received aggregate net proceeds of approximately $85,598 after deducting underwriting discounts, commissions and other offering expenses payable by the Company of approximately $5,814. The Pre-Funded Warrants are exercisable at any time after the date of issuance. A holder of Pre-Funded Warrants may not exercise the Pre-Funded Warrant if the holder, together with its affiliates, would beneficially own more than 9.99% of the number of shares of the Company’s common stock outstanding immediately after giving effect to such exercise. A holder of Pre-Funded Warrants may increase or decrease this percentage by providing at least 61 days’ prior notice to the Company. As of March 31, 2020, none of the warrants had been exercised.

Stock-based compensation

12 Months Ended

Mar. 31, 2020

Stock-based compensation

Stock-based compensation

9. Stock‑based compensation

2015 Enterprise Management Incentive Share Option Plan

The 2015 Enterprise Management Incentive Share Option Plan of Replimune UK (the “2015 Plan”) provided for Replimune UK to grant incentive stock options, non‑statutory stock options, stock awards, stock units, stock appreciation rights and other stock‑based awards. Incentive stock options are granted only to the Company’s employees, including officers and directors who are also employees. Non‑statutory stock options are granted to employees, members of the board of directors, outside advisors and consultants of the Company.

2017 Equity Compensation Plan

In July 2017, in conjunction with the Reorganization, the 2015 Plan was terminated, and all awards were cancelled with replacement awards issued under the 2017 Equity Compensation Plan (the “2017 Plan”). Subsequent to the Reorganization, no additional grants will be made under the 2015 Plan and any outstanding awards under the 2015 Plan will continue with their original terms. The Company concluded that the cancellation of the 2015 Plan and issuance of replacement awards under the 2017 Plan was a modification with no change in the material rights and preferences and therefore no recorded change in the fair value of each respective award.

The Company’s 2017 Plan provides for the Company to grant incentive stock options or non‑statutory stock options, stock awards, stock units, stock appreciation rights and other stock‑based awards. Incentive stock options may be granted only to the Company’s employees, including officers and directors who are also employees. Restricted stock awards and non‑statutory stock options may be granted to employees, officers, members of the board of directors, advisors and consultants of the Company. The maximum number of common shares that may be issued under the 2017 Plan was 2,659,885 of which 0 remained available for future grants as of March 31, 2020. Shares with respect to which awards have expired, terminated, surrendered or cancelled under the 2017 Plan without having been fully exercised will be available for future awards under the 2017 Plan. In addition, shares of common stock that are tendered to the Company by a participant to exercise an award are added to the number of shares of common stock available for the grant of awards.

2018 Omnibus Incentive Compensation Plan

On July 9, 2018, the Company’s board of directors adopted, and the Company’s stockholders approved the 2018 Omnibus Incentive Compensation Plan (the “2018 Plan”), which became effective immediately prior to the effectiveness of the registration statement for the Company’s initial public offering. The 2018 Plan provides for the issuance of incentive stock options, non‑qualified stock options, stock awards, stock units, stock appreciation rights and other stock‑based awards. The number of shares initially reserved for issuance under the 2018 Plan is 3,617,968 shares. If any options or stock appreciation rights, including outstanding options and stock appreciation rights granted under the 2017 Plan (up to 2,520,247 shares), terminate, expire, or are canceled, forfeited, exchanged, or surrendered without having been exercised, or if any stock awards, stock units or other stock‑based awards, including outstanding awards granted under the 2017 Plan, are forfeited, terminated, or otherwise not paid in full in shares of common stock, the shares of the Company’s common stock subject to such grants will be available for purposes of our 2018 Plan. On April 1, 2019, the number of shares reserved for issuance under the 2018 Plan automatically increased by 1,266,278 shares pursuant to the terms of the 2018 Plan. As of March 31, 2020, 2,122,012 shares remained available for future grants under the 2018 Plan.

The 2015 Plan, the 2017 Plan and the 2018 Plan was administered by the board of directors or, at the discretion of the board of directors, by a committee of the board of directors. However, the board of directors shall administer and approve all grants made to non‑employee directors. The exercise prices, vesting and other restrictions are determined at the discretion of the board of directors, except that the exercise price per share of incentive stock options may not be less than 100% of the fair market value of the common stock on the date of grant (or 110% of fair value in the case of an award granted to employees who hold more than 10% of the total combined voting power of all classes of stock at the time of grant) and the term of stock options may not be greater than five years for an incentive stock option granted to a 10% stockholder and greater than ten years for all other options granted. Stock options awarded under both plans expire ten years after the grant date, unless the board of directors sets a shorter term. Vesting periods for both plans are determined at the discretion of the board of directors. Incentive stock options granted to employees and non‑statutory options granted to employees, officers, members of the board of directors, advisors, and consultants of the Company typically vest over four years.

Employee Stock Purchase Plan

On July 9, 2018, the Company’s board of directors adopted and the Company’s stockholders approved the Employee Stock Purchase Plan (the “ESPP”), which became effective immediately prior to the effectiveness of the registration statement for the Company’s IPO. The total shares of common stock initially reserved for issuance under the ESPP is limited to 348,612 shares. In addition, as of the first trading day of each fiscal year during the term of the ESPP (excluding any extensions), an additional number of shares of the Company’s common stock equal to 1% of the total number of shares outstanding on the last trading day in the immediately preceding fiscal year or 697,224 shares, whichever is less (or such lesser amount as determined by the Company’s board of directors) will be added to the number of shares authorized under the ESPP. In accordance, on April 1, 2019, the number of shares reserved for issuance under the ESPP automatically increased by 316,569 shares, for a total of 665,181 shares reserved for the ESPP. If the total number of shares of common stock to be purchased pursuant to outstanding purchase rights on any particular date exceed the number of shares then available for issuance under the ESPP, then the plan administrator will allocate the available shares pro‑rata and refund any excess payroll deductions or other contributions to participants.

Stock option valuation

The fair value of stock option grants is estimated using the Black-Scholes option-pricing model. The Company lacks company-specific historical and implied volatility information. Therefore, it estimated its expected stock volatility based on the historical volatility of a publicly traded set of peer companies. For options with service-based vesting conditions, the expected term of the Company’s stock options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The expected term of stock options granted to non-employees is equal to the contractual term of the option award. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future.

The following table presents, on a weighted‑average basis, the assumptions that the Company used to determine the grant‑date fair value of stock options granted to employees and directors:


	Year Ended
	March 31,
	2020		2019		2018
Risk-free interest rate	2.12	%	2.81	%	2.01	%
Expected term (in years)	6.0		6.1		6.0
Expected volatility	71.4	%	62.0	%	75.0	%
Expected dividend yield	0	%	0	%	0	%

The following table presents the assumptions that the Company used to determine the grant‑date fair value of stock options granted to a non‑employee:


	Year Ended
	March 31, 2018
Risk-free interest rate	2.29	%
Expected term (in years)	10.0
Expected volatility	75.0	%
Expected dividend yield	0	%

All outstanding non-employee options granted during the year ended March 31, 2018 have vested, and there were no options granted to non-employees during the year ended March 31, 2020 or 2019.

Stock options

The following table summarizes the Company’s stock option activity:


		Weighted		Weighted Average
	Number of	Average		Contractual Term	Aggregate
	Shares	Exercise Price		(Years)	Intrinsic Value
Outstanding as of March 31, 2019	3,721,784	$	7.14	8.61	$	30,150
Granted	1,637,035		15.07	9.21
Exercised	(207,673)		2.65
Cancelled	(186,765)		11.48
Outstanding as of March 31, 2020	4,964,381	$	9.78	8.02	$	15,344
Options exercisable as of March 31, 2019	1,278,330	$	2.51	7.75	$	16,249
Options exercisable as of March 31, 2020	2,117,721	$	5.66	7.20		11,733

The aggregate intrinsic value of stock options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the Company’s common stock.

The weighted average grant-date fair value per share of stock options granted during the years ended March 31, 2020 and 2019 was $9.70 and $8.82, respectively.

The total fair value of options vested during the years ended March 31, 2020 and 2019 was $5,440 and $1,298, respectively.

As of March 31, 2020, there were no outstanding unvested service-based stock options held by non-employees.

Stock‑based compensation expense

Stock‑based compensation expense was classified in the consolidated statements of operations as follows:


	Year Ended
	March 31,
	2020		2019		2018
Research and development	$	3,689	$	1,488	$	335
General and administrative		4,052		1,242		477
	$	7,741	$	2,730	$	812

As of March 31, 2020, total unrecognized compensation cost related to the unvested stock‑based awards was $18,732, which is expected to be recognized over a weighted average period of 2.56 years.

Net loss per share

12 Months Ended

Mar. 31, 2020

Net loss per share

Net loss per share

10. Net loss per share

Basic and diluted net loss per share attributable to common stockholders was calculated as follows:


	Year Ended March 31,
	2020		2019		2018
Numerator:
Net loss attributable to common stockholders	$	(52,625)	$	(30,834)	$	(19,702)
Denominator:
Weighted average common shares outstanding, basic and diluted		34,261,548		23,198,400		4,978,539
Net loss per share attributable to common stockholders, basic and diluted	$	(1.54)	$	(1.33)	$	(3.96)

Included within weighted average common shares outstanding are common shares issuable upon the exercise of the pre-funded warrants as the warrants are exercisable at any time for nominal consideration, and as such, the shares are considered outstanding for the purpose of calculating basic and diluted net loss per share attributable to common stockholders.

The Company’s potentially dilutive securities, which include stock options, preferred stock and warrants to purchase shares of series seed preferred stock, have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted average number of common shares outstanding used to calculate both basic and diluted net loss per share attributable to common stockholders is the same. The Company excluded the following potential common shares, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti‑dilutive effect:


	Year Ended March 31,
	2020	2019	2018
Options to purchase common stock	4,964,381	3,721,784	2,520,247
Convertible preferred stock (as converted to common stock)	—	—	19,157,360
Warrants to purchase convertible preferred stock (as converted to common stock)	497,344	497,344	497,344
	5,461,725	4,219,128	22,174,951

Significant agreements	12 Months Ended
Significant agreements	Mar. 31, 2020
Significant agreements
Significant agreements	11. Significant agreements Agreement with Bristol-Myers Squibb Company In February 2018, the Company entered into an agreement with Bristol-Myers Squibb Company (“BMS”). Pursuant to the agreement, BMS will provide to the Company, at no cost, a compound for use in the Company’s ongoing clinical trial. Under the agreement, the Company will sponsor, fund and conduct the clinical trial in accordance with an agreed-upon protocol. BMS granted the Company a non-exclusive, non-transferrable, royalty-free license (with a right to sublicense) under its intellectual property to its compound in the clinical trial and agreed to supply its compound, at no cost to the Company, for use in the clinical trial. In January 2020, this agreement was expanded to cover an additional cohort of 125 patients with anti-PD-1 refractory melanoma. Unless earlier terminated, the agreement will remain in effect until (i) the completion of the clinical trial, (ii) all related clinical trial data have been delivered to both parties and (iii) the completion of any statistical analyses and bioanalyses contemplated by the clinical trial protocol or any analysis otherwise agreed upon by the parties. The agreement may be terminated by either party (i) in the event of an uncured material breach by the other party, (ii) in the event the other party is insolvent or in bankruptcy proceedings or (iii) for safety reasons. Upon termination, the licenses granted to the Company to use BMS’s compound in the clinical trial will terminate. As of March 31, 2020, the Company had not incurred any costs and does not expect to incur future costs in connection with this agreement. In April 2019, the Company entered into a separate agreement with BMS on terms similar to the terms set forth in the agreement described above, pursuant to which BMS will provide to the Company, at no cost, nivolumab for use in the Company’s Phase 1 clinical trial of RP2 in combination with nivolumab. Agreement with Regeneron Pharmaceuticals, Inc. In May 2018, the Company entered into an agreement with Regeneron Pharmaceuticals, Inc. (“Regeneron”). The Company and Regeneron are each independently developing compounds for the treatment of certain tumor types. Pursuant to the agreement, the Company and Regeneron will undertake one or more clinical trials using a combination of the compounds being developed by each entity. Under the agreement, each study will be conducted under terms set out in a separately agreed upon study plan that will identify the name of the sponsor and which party will manage the particular clinical trial, and include the protocol, the budget and a schedule of clinical obligations. In June 2018, under the terms of the agreement between the Company and Regeneron, the parties agreed to the first study plan. The Company and Regeneron have agreed to the protocol, budget, sample testing and clinical obligations schedule under the study plan. Development and supply costs associated with the study plan will be split equally between the Company and Regeneron. Pursuant to the terms of the agreement, each party granted the other party a non‑exclusive license under its respective intellectual property and agreed to contribute the necessary resources needed to fulfill its respective obligations, in each case, under the terms of the agreed-upon or to‑be agreed upon study plans. Development costs of a particular clinical trial will be split equally between the Company and Regeneron. The agreement may be terminated by either party if (i) there is no active study plan for which a final study report has not been completed, (ii) the parties have not entered into a study plan for an additional clinical trial within a period of time after the delivery of the most recent final study report or (iii) in the event of a material breach. The Company will account for costs incurred as part of the study, including costs to supply compounds for use in the study, as research and development expenses within the consolidated statement of operations. The Company will recognize any amounts received from Regeneron in connection with this agreement as an offset to research and development expense within the consolidated statement of operations. Under the terms of the agreement, on a quarterly basis the Company and Regeneron true-up costs of the study and make corresponding payments to the party that incurred the majority of the costs. During the year ended March 31, 2020, the Company did not receive or make any payments under the terms of the agreement to Regeneron. As of March 31, 2020 and 2019, the Company recorded $971 and $337 of receivables from Regeneron in connection with this agreement in prepaid expenses and other current assets in the consolidated balance sheet, respectively.

Commitments and contingencies

12 Months Ended

Mar. 31, 2020

Commitments and contingencies

Commitments and contingencies

12. Commitments and contingencies

Leases

In December 2015, the Company entered into a lease agreement for office space in Woburn, Massachusetts, which expires on March 30, 2021. The Company has the option to extend the lease agreement for successive periods of five years. Monthly lease payments, inclusive of base rent and ancillary charges, total $7. Monthly base rent is subject to increase each year in proportion to the Consumer Price Index. The lease was terminated by the Company in March 2020, prior to the expiration of the lease term.

In April 2016, the Company entered into a lease agreement for office and laboratory space in Abingdon, England, which expires on April 3, 2026. The Company has the right to terminate the lease as of April 4, 2021 upon at least nine months’ prior written notice. Monthly lease payments are inclusive of base rent, ancillary charges, non‑rent shared tenant occupancy costs and the respective value added tax to be paid. Monthly lease payments include base rent of approximately $23 through December 3, 2016 and $31 thereafter. Monthly base rent is subject to increase after April 2021 in proportion to the Retail Price Index. The lease is classified as an operating lease.

In June 2018, the Company entered into an agreement to lease approximately 63,000 square feet of office, manufacturing and laboratory space in Framingham, Massachusetts. Pursuant to the lease agreement, the lease term commenced in December 2018, subject to the landlord completing certain agreed upon landlord improvements. The rent commencement date started in August 2019. The initial lease term is ten years from the rent commencement date and includes two optional five-year extensions. Annual lease payments during the first year were $2,373 with increases of 3.0% each year thereafter until the expiration of the lease.

Prior to the adoption of ASC 842 on April 1, 2019, the Company was deemed to be the accounting owner of the leased space during the construction period, which began in December 2018, because of certain indemnification provisions within the lease agreement. As a result, the Company had capitalized $11,514 as a build-to-suit lease asset within property and equipment as of March 31, 2019. Upon transition to ASC 842 on April 1, 2019, the Company determined that it did not control the build-to-suit lease asset and the arrangement has been accounted for under the guidance set forth within ASC 842, leases. Upon the adoption of ASC 842, the Company derecognized $11,514 of the build-to-suit lease asset and $6,561 of financing obligations and recorded long term prepaid rent of $5,006 on the consolidated balance sheet as landlord owned tenant improvements were determined to be prepaid rent under the guidance set forth within ASC 842. The Company continued to record construction costs incurred during the construction period subsequent to April 1, 2019 as prepaid rent.

Construction was completed associated with approximately 10,500 square feet of the leased space in Framingham, Massachusetts and the Company occupied the building as office space beginning August 1, 2019. The Company recorded a right-of-use asset and lease liability associated with the occupied space as of August 1, 2019. The Company recorded $2,368 in related construction costs to the right-of-use asset upon the lease commencement date which were reclassified from prepaid rent. The Company occupied the remainder of the facility, approximately 53,000 square feet used as laboratory space, on October 22, 2019. The Company recorded a right-of-use asset and lease liability associated with the remaining space as of October 22, 2019. The Company recorded $18,164 in related construction costs and $261 in rent payments made prior to the lease commencement date to the right-of-use asset upon the lease commencement date which were reclassified from prepaid rent. The lease is classified as a financing lease.

In June 2019, the Company entered into an agreement to lease approximately 18,700 square feet of office space in Woburn, Massachusetts. Pursuant to the lease agreement, the lease term commenced in August 2019. The rent commenced in September 2019. The initial lease term is ten years from the rent commencement date and includes an optional five-year extension. Annual lease payments during the first year are $488 with increases of approximately 1.6% each year. The Company recorded a right-of-use asset and a lease liability of $4,363 upon the commencement date of the lease and the lease is classified as an operating lease.

The Company determines if an arrangement is a lease at inception. Operating leases are included in our balance sheet as right-to-use—operating leases, operating lease liabilities , current and operating lease liabilities , non-current. Finance leases are included in the balance sheet as right-to-use asset—finance lease finance lease liabilities, current, and finance lease liabilities, non-current. Certain of the Company’s lease agreements contain renewal options; however, the Company does not recognize right-of-use assets or lease liabilities for renewal periods unless it is determined that the Company is reasonably certain of renewing the lease at inception or when a triggering event occurs. As the Company’s leases do not provide an implicit rate, the Company estimated the incremental borrowing rate in calculating the present value of the lease payments. Since the Company elected to account for each lease component and its associated non-lease components as a single combined lease component, all contract consideration was allocated to the combined lease component. Some of the Company’s lease agreements contain rent escalation clauses (including index-based escalations). The Company recognizes the minimum rental expense on a straight-line basis based on the fixed components of a lease arrangement. The Company amortizes this expense over the term of the lease beginning with the date of initial possession, which is the date the Company can enter the leased space and begin to make improvements in preparation for its intended use. Variable lease components represent amounts that are not fixed in nature and are not tied to an index or rate, and are recognized as incurred.


	Year Ended
	March 31, 2020
Lease cost
Finance lease costs:
Amortization of right-to-use asset	$	1,274
Interest on lease liabilities		1,185
Operating lease costs		885
Total lease cost	$	3,344

Finance lease costs of $239 are recognized in general and administrative expenses for the year ended March 31, 2020 and $1,034 in research and development expenses for the year ended March 31, 2020. Operating leases costs are recognized in general and administrative expenses for the year ended March 31, 2020. The following table summarizes the maturity of the Company’s lease liabilities on an undiscounted cash flow basis and a reconciliation to the operating and financing lease liabilities recognized on our balance sheet as of March 31, 2020:


	March 31, 2020
	Operating leases		Financing lease		Total
2021	$	873	$	2,411	$	3,284
2022		586		2,483		3,069
2023		596		2,558		3,154
2024		605		2,634		3,239
2025		614		2,714		3,328
Thereafter		2,791		43,685		46,476
Total lease payments		6,065		56,485		62,550
Less: interest		1,455		29,107		30,562
Total lease liabilities	$	4,610	$	27,378	$	31,988

The following table summarizes the future minimum lease payments due under the Company's operating leases as of March 31, 2019:


2020	$	2,062
2021		2,901
2022		2,493
2023		2,568
2024		2,645
2025		2,725
Thereafter		12,770
	$	28,164

The following table provides lease disclosure as of and for the year ended March 31, 2020:


	March 31, 2020
Leases
Right-to-use operating lease asset	$	4,425
Right-to-use finance lease asset		46,925
Total lease assets	$	51,350
Operating lease liabilities, current	$	873
Finance lease liabilities, current		2,411
Operating lease liabilities, non-current		3,737
Finance lease liabilities, non-current		24,967
Total lease liabilities	$	31,988
Other information
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	747
Operating cash flows from finance leases	$	1,185
Financing cash flows from finance leases	$	59
Right-to-use asset obtained in exchange for new operating lease liabilities	$	5,152
Right-to-use asset obtained in exchange for new financing lease liabilities	$	48,224
Variable lease costs	$	—
Short term lease costs	$	—
Weighted-average remaining lease term-operating leases		8.7 years
Weighted-average remaining lease term-financing leases		19.3 years
Weighted-average discount rate-operating leases		7	%
Weighted-average discount rate-financing leases		8	%

The variable lease costs and short-term lease costs were insignificant for the year ended March 31, 2020.

Manufacturing commitments

The Company has entered into an agreement with a contract manufacturing organization to provide clinical trial products. As of March 31, 2020, the Company had committed to minimum payments under these arrangements totaling $3,569 through March 31, 2021. As of March 31, 2019, the Company had committed to minimum payments under these arrangements totaling $4,694 through March 31, 2020.

Indemnification agreements

In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company is not aware of any claims under indemnification arrangements, and therefore it has not accrued any liabilities related to such obligations in its consolidated financial statements as of March 31, 2020 or 2019.

Legal proceedings

The Company is not a party to any litigation and does not have contingency reserves established for any litigation liabilities.

Benefit plans	12 Months Ended
Benefit plans	Mar. 31, 2020
Benefit plans
Benefit plans	13. Benefit plans The Company established a defined‑contribution savings plan under Section 401(k) of the Code (the “401(k) Plan”). The 401(k) Plan covers substantially all employees who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre‑tax basis. Matching contributions to the 401(k) Plan may be made at the discretion of the Company’s board of directors. During the years ended March 31, 2020, 2019 and 2018, the Company made contributions totaling $232, $102 and $49, respectively, to the 401(k) Plan. We provide a pension contribution plan for our employees in the United Kingdom, pursuant to which we match our employees’ contributions each year in amounts up to 8% of their annual base salary.

Income taxes

12 Months Ended

Mar. 31, 2020

Income taxes

Income taxes

14. Income taxes

On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”) was enacted in the United States. The CARES Act provides numerous tax provisions and other stimulus measures, including temporary changes regarding the prior and future utilization of net operating losses and technical corrections from prior tax legislation for tax depreciation of certain qualified improvement property. We evaluated the provisions of the CARES Act and do not anticipate the associated impacts, if any, will have a material effect on our financial position.

During the years ended March 31, 2020, 2019 and 2018, the Company recorded no income tax benefits for the net operating losses incurred generated during the years then ended, due to its uncertainty of realizing a benefit from those items. The Company’s net loss before income taxes were generated in the United States and the United Kingdom.

Net loss before income taxes for the years ended March 31, 2020, 2019 and 2018 were as follows:


	Year Ended March 31,
	2020		2019		2018
United States	$	(12,963)	$	(9,483)	$	(8,992)
Foreign (United Kingdom)		(39,662)		(21,351)		(10,710)
	$	(52,625)	$	(30,834)	$	(19,702)

A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate for the years ended March 31, 2020, 2019 and 2018 is as follows:


	March 31,
	2020		2019		2018
U.S. Federal statutory income tax rate	(21.00)	%	(21.00)	%	(21.00)	%
State taxes, net of federal benefit	(1.6)		(1.5)		(2.6)
Research and development expenses	2.2		3.1		3.8
Remeasurement of deferred taxes as a result of tax reform	—		—		2.6
Foreign tax rate differential	2.8		2.4		2.2
Change in valuation allowance	16.0		15.5		14.0
Return to provision	1.9		0.4		—
Other	(0.3)		1.1		1.0
Effective income tax rate	0.00	%	0.00	%	0.00	%

Components of the Company’s deferred tax assets as of March 31, 2020 and 2019 were as follows:


	March 31,
	2020		2019
Deferred tax assets:
Foreign net operating loss carryforwards	$	9,092	$	4,079
Federal net operating loss carryforwards		2,450		2,223
State net operating loss carryforwards		1,054		684
Property, plant and equipment		5,499		—
Capitalized start-up costs		1,748		1,886
Stock compensation		2,526		573
Accrued expenses		341		1,793
Lease liability		8,705		—
Total deferred tax assets		31,415		11,238
Deferred tax liabilities:
Right-to-use asset		(13,998)		—
Property, plant and equipment		—		(1,842)
Other		(88)		—
Total deferred tax liabilities		(14,086)		(1,842)
Valuation allowance		(17,329)		(9,396)
Net deferred tax assets	$	—	$	—

As of March 31, 2020, the Company had federal and foreign net operating loss carryforwards of approximately $11,667 and $53,483, respectively, which can be carried forward indefinitely. As of March 31, 2020, the Company had state net operating loss carryforwards of $16,670, which will expire between 2039 and 2040.

Utilization of the U.S. federal and state net operating loss carryforwards may be subject to a substantial annual limitation under Section 382 of the Internal Revenue Code of 1986, as amended, and corresponding provisions of state law, due to ownership changes that have occurred previously or that could occur in the future. These ownership changes may limit the amount of net operating loss carryforwards that can be utilized annually to offset future taxable income and tax liabilities, respectively. The Company has not completed a study to assess whether a change of ownership has occurred, or whether there have been multiple ownership changes since its formation, due to the significant cost and complexity associated with such a study. Any limitation may result in expiration of a portion of the net operating loss carryforwards before utilization. Further, until a study is completed by the Company and any limitation is known, no amounts are being presented as an uncertain tax position.

Changes in the valuation allowance for deferred tax assets during the years ended March 31, 2020 and 2019 related primarily to the increase in net operating loss carryforwards were as follows:


	March 31,
	2020		2019
Valuation allowance as of beginning of year	$	9,396	$	4,724
Increases recorded to income tax provision		8,047		4,672
Decreases recorded to income tax provision for equity		(114)		—
Valuation allowance as of end of year	$	17,329	$	9,396

As of March 31, 2020 and 2019, the Company had not recorded any amounts for unrecognized tax benefits. The Company’s policy is to record interest and penalties related to income taxes as part of its income tax provision. As of March 31, 2020 and 2019, the Company had no accrued interest or penalties related to uncertain tax positions and no amounts had been recognized in the Company’s consolidated statements of operations and comprehensive loss.

The Company files income tax returns in the United States, Massachusetts and the United Kingdom as prescribed by the tax laws of the jurisdictions in which it operates. In the normal course of business, the Company is subject to examination by U.S. federal, state and foreign jurisdictions, where applicable. There are currently no pending tax examinations. The Company is open to future tax examination in the U.S. under statute from 2017 to the present and in the United Kingdom from 2016 to the present.

Geographic information

12 Months Ended

Mar. 31, 2020

Geographic information

Geographic information

15. Geographic information

The Company operates in two geographic regions: the United States (Massachusetts) and the United Kingdom (Oxfordshire). Information about the Company’s long‑lived assets held in different geographic regions is presented in the tables below:


	March 31,
	2020		2019
United States	$	6,357		11,648
United Kingdom		503		511
	$	6,860	$	12,159

Quarterly financial data (unaudited)

12 Months Ended

Mar. 31, 2020

Quarterly financial data (unaudited)

Quarterly financial data (unaudited)

16. Quarterly financial data (unaudited)

The following information has been derived from unaudited consolidated financial statements that, in the opinion of management, include all recurring adjustments necessary for a fair statement of such information.


	Three Months Ended
	March 31, 2020	December 31, 2019	September 30, 2019	June 30, 2019
Operating expenses	16,385	16,664	12,242	10,907
Net loss attributable to common stockholders	(15,789)	(16,189)	(11,139)	(9,508)
Net loss per share attributable to common
stockholders, basic and diluted	(0.41)	(0.46)	(0.35)	(0.30)


	Three Months Ended
	March 31, 2019	December 31, 2018	September 30, 2018	June 30, 2018
Operating expenses	7,826	10,137	7,104	5,879
Net loss attributable to common stockholders	(6,656)	(7,673)	(6,461)	(10,044)
Net loss per share attributable to common
stockholders, basic and diluted	(0.29)	(0.24)	(0.26)	(2.02)

Subsequent events	12 Months Ended
Subsequent events	Mar. 31, 2020
Subsequent events
Subsequent events	17. Subsequent events For its consolidated financial statements as of March 31, 2020 and for the year then ended, the Company evaluated subsequent events through the date on which those financial statements were issued. Hercules Loan Agreement On June 1, 2020, the Company amended the Hercules Loan Agreement to increase the secured term loan facility from $30,000 to $40,000 by adding a fourth advance of up to $10,000 which may be borrowed between July 1, 2021 and December 15, 2021. The amended agreement contains certain borrowing milestones as defined in the agreement. Additionally, the Amortization Date was changed from March 1, 2022 to September 1, 2022 to extend the interest only payment period by six months.

Summary of significant accounting policies (Policies)

12 Months Ended

Mar. 31, 2020

Summary of significant accounting policies

Principles of consolidation

Use of estimates

Foreign currency and currency translation

Concentrations of credit risk and of significant suppliers

Cash and cash equivalents

Restricted cash

Short-term investments

Short‑term investments

The Company’s short‑term debt security investments as of March 31, 2020 and 2019 had maturities of less than one year.

Deferred offering costs

Property, plant and equipment


		Estimated Useful life
Office equipment		5 years
Computer equipment		3 years
Plant, plant and laboratory equipment		5 years
Leasehold improvements		Lesser of lease term or 10 years

Impairment of long-lived assets

Impairment of long‑lived assets

Fair value measurements

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

Warrant liability

Debt issuance costs

Segment information

Research and development costs

Research contract costs and accruals

Patent costs

Stock-based compensation

Stock‑based compensation

Research and development incentives and receivable

Comprehensive loss

Income taxes

Net income (loss) per share

Recently adopted accounting pronouncements

The following table summarizes the financial impact on the Company’s consolidated balance sheet upon the adoption of ASU 2016-02 and the cumulative effect adjustment on April 1, 2019:


	March 31, 2019		Adjustments		April 1, 2019
Property, plant, and equipment, net	$	12,159	$	(11,514)	$	645
Right-to-use asset	$	—	$	789	$	789
Long term prepaid rent	$	—	$	5,006	$	5,006
Lease liabilities, current	$	—	$	388	$	388
Lease liabilities, non-current	$	—	$	449	$	449
Accrued expenses	$	2,801	$	(24)	$	2,777
Deferred rent, net of current portion	$	24	$	(24)	$	—
Financing obligation	$	6,561	$	(6,561)	$	—
Accumulated deficit	$	(59,766)	$	93	$	(59,673)

Recently issued accounting pronouncements

Summary of significant accounting policies (Tables)

12 Months Ended

Mar. 31, 2020

Summary of significant accounting policies

Schedule of estimated useful life of property, plant and equipment


		Estimated Useful life
Office equipment		5 years
Computer equipment		3 years
Plant, plant and laboratory equipment		5 years
Leasehold improvements		Lesser of lease term or 10 years

Summary of financial impact on consolidated balance sheet upon the adoption of ASU 2016-02 and the cumulative effect adjustment


	March 31, 2019		Adjustments		April 1, 2019
Property, plant, and equipment, net	$	12,159	$	(11,514)	$	645
Right-to-use asset	$	—	$	789	$	789
Long term prepaid rent	$	—	$	5,006	$	5,006
Lease liabilities, current	$	—	$	388	$	388
Lease liabilities, non-current	$	—	$	449	$	449
Accrued expenses	$	2,801	$	(24)	$	2,777
Deferred rent, net of current portion	$	24	$	(24)	$	—
Financing obligation	$	6,561	$	(6,561)	$	—
Accumulated deficit	$	(59,766)	$	93	$	(59,673)

Fair value of financial assets and liabilities (Tables)

12 Months Ended

Mar. 31, 2020

Fair value of financial assets and liabilities

Schedule of company's financial assets and liabilities measured at fair value on a recurring basis


	Fair Value Measurements
	as of March 31, 2020 Using:
	Level 1		Level 2		Level 3		Total
Assets
Money market funds	$	—	$	36,712	$	—	$	36,712
Commercial paper		—		21,884		—		21,884
US Treasury bonds		—		35,810		—		35,810
US Government Agency bonds		—		15,295		—		15,295
Corporate debt securities		—		36,066		—		36,066
	$	—	$	145,767	$	—	$	145,767


	Fair Value Measurements
	as of March 31, 2019 Using:
	Level 1		Level 2		Level 3		Total
Assets
Money market funds	$	—	$	2,676	$	—	$	2,676
Commercial paper		—		46,687		—		46,687
US Government Agency bonds		—		20,884		—		20,884
US Treasury bonds		—		41,057		—		41,057
Corporate debt securities		—		8,467		—		8,467
	$	—	$	119,771	$	—	$	119,771

Schedule of unobservable inputs of the warrant liability upon the conversion date


		Year Ended
		March 31, 2019
Risk-free interest rate		2.81	%
Expected term (in years)		7.2
Expected volatility		64.4	%
Expected dividend yield		0	%
Fair value of series seed preferred stock	$	15.00

Schedule of roll forward of the warrant liability


	Warrant
	Liability
Balance at March 31, 2018	$	1,642
Change in fair value		5,452
Conversion of convertible preferred stock warrant into common stock warrant		(7,094)
Balance at March 31, 2019	$	—

Short-term investments (Tables)

12 Months Ended

Mar. 31, 2020

Short-term investments

Schedule of short-term investments


	March 31, 2020
			Gross		Gross
	Amortized		unrealized		unrealized
	cost		gains		losses		Fair value
Commercial paper	$	21,818	$	66	$	—	$	21,884
US Government agency bonds		15,217		78		—		15,295
US Treasury bonds		35,590		220		—		35,810
Corporate debt securities		36,107		24		(65)		36,066
	$	108,732	$	388	$	(65)	$	109,055


	March 31, 2019
			Gross		Gross
	Amortized		unrealized		unrealized
	cost		gains		losses		Fair value
Commercial paper	$	46,687	$	2	$	(2)	$	46,687
US Government agency bonds		15,889		4		—		15,893
US Treasury bonds		38,047		13		—		38,060
Corporate debt securities		8,469		—		(2)		8,467
	$	109,092	$	19	$	(4)	$	109,107

Property, plant and equipment, net (Tables)

12 Months Ended

Mar. 31, 2020

Property, plant and equipment, net

Schedule of property, plant and equipment, net


	March 31,
	2020		2019
Construction in progress	$	1,217	$	124
Plant and laboratory equipment		3,669		584
Leasehold improvements		532		154
Computer equipment		1,658		138
Office equipment		721		49
Build-to-suit lease asset		—		11,514
		7,797		12,563
Less: Accumulated depreciation and amortization		(937)		(404)
	$	6,860	$	12,159

Accrued expenses and other current liabilities (Tables)

12 Months Ended

Mar. 31, 2020

Accrued expenses and other current liabilities

Schedule of accrued expenses and other current liabilities


	March 31,
	2020		2019
Accrued researched and development costs	$	2,009	$	530
Accrued compensation and benefits costs		2,065		1,510
Accrued professional fees		779		464
Deferred rent		—		24
Other		303		273
	$	5,156	$	2,801

Long-term debt (Tables)

12 Months Ended

Mar. 31, 2020

Long-term debt

Schedule of long-term debt


	March 31,
	2020

Principal amount of long-term debt	$	10,000
Unamortized debt discount		(199)
Long-term debt, net of discount	$	9,801

Schedule of future payments of long term debt


Future long-term debt payments:
2021	$	—
2022		527
2023		6,558
2024		2,915
Total debt payments	$	10,000

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 505
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-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 235
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-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
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Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 835
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-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

Stock-based compensation (Tables)

12 Months Ended

Mar. 31, 2020

Stock-based Compensation

Summary of stock option activity


		Weighted		Weighted Average
	Number of	Average		Contractual Term	Aggregate
	Shares	Exercise Price		(Years)	Intrinsic Value
Outstanding as of March 31, 2019	3,721,784	$	7.14	8.61	$	30,150
Granted	1,637,035		15.07	9.21
Exercised	(207,673)		2.65
Cancelled	(186,765)		11.48
Outstanding as of March 31, 2020	4,964,381	$	9.78	8.02	$	15,344
Options exercisable as of March 31, 2019	1,278,330	$	2.51	7.75	$	16,249
Options exercisable as of March 31, 2020	2,117,721	$	5.66	7.20		11,733

Schedule of stock-based compensation expense


	Year Ended
	March 31,
	2020		2019		2018
Research and development	$	3,689	$	1,488	$	335
General and administrative		4,052		1,242		477
	$	7,741	$	2,730	$	812

Employees stock options

Stock-based Compensation

Schedule of assumptions used to determine the grant-date fair value of stock options granted


	Year Ended
	March 31,
	2020		2019		2018
Risk-free interest rate	2.12	%	2.81	%	2.01	%
Expected term (in years)	6.0		6.1		6.0
Expected volatility	71.4	%	62.0	%	75.0	%
Expected dividend yield	0	%	0	%	0	%

Non Employee Stock Option Member

Stock-based Compensation

Schedule of assumptions used to determine the grant-date fair value of stock options granted


	Year Ended
	March 31, 2018
Risk-free interest rate	2.29	%
Expected term (in years)	10.0
Expected volatility	75.0	%
Expected dividend yield	0	%

Net loss per share (Tables)

12 Months Ended

Mar. 31, 2020

Net loss per share

Schedule of calculation of basic and diluted net loss per share attributable to common stockholders


	Year Ended March 31,
	2020		2019		2018
Numerator:
Net loss attributable to common stockholders	$	(52,625)	$	(30,834)	$	(19,702)
Denominator:
Weighted average common shares outstanding, basic and diluted		34,261,548		23,198,400		4,978,539
Net loss per share attributable to common stockholders, basic and diluted	$	(1.54)	$	(1.33)	$	(3.96)

Schedule of anti-dilutive securities excluded from the computation of diluted net loss per share attributable to common shareholders


	Year Ended March 31,
	2020	2019	2018
Options to purchase common stock	4,964,381	3,721,784	2,520,247
Convertible preferred stock (as converted to common stock)	—	—	19,157,360
Warrants to purchase convertible preferred stock (as converted to common stock)	497,344	497,344	497,344
	5,461,725	4,219,128	22,174,951

Commitments and contingencies (Tables)

12 Months Ended

Mar. 31, 2020

Commitments and contingencies

Schedule of variable lease components


	Year Ended
	March 31, 2020
Lease cost
Finance lease costs:
Amortization of right-to-use asset	$	1,274
Interest on lease liabilities		1,185
Operating lease costs		885
Total lease cost	$	3,344

Summary of the maturity of company's lease liabilities


	March 31, 2020
	Operating leases		Financing lease		Total
2021	$	873	$	2,411	$	3,284
2022		586		2,483		3,069
2023		596		2,558		3,154
2024		605		2,634		3,239
2025		614		2,714		3,328
Thereafter		2,791		43,685		46,476
Total lease payments		6,065		56,485		62,550
Less: interest		1,455		29,107		30,562
Total lease liabilities	$	4,610	$	27,378	$	31,988

Schedule of future annual minimum lease payment commitments


2020	$	2,062
2021		2,901
2022		2,493
2023		2,568
2024		2,645
2025		2,725
Thereafter		12,770
	$	28,164

Schedule of additional information related to leases


	March 31, 2020
Leases
Right-to-use operating lease asset	$	4,425
Right-to-use finance lease asset		46,925
Total lease assets	$	51,350
Operating lease liabilities, current	$	873
Finance lease liabilities, current		2,411
Operating lease liabilities, non-current		3,737
Finance lease liabilities, non-current		24,967
Total lease liabilities	$	31,988
Other information
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	747
Operating cash flows from finance leases	$	1,185
Financing cash flows from finance leases	$	59
Right-to-use asset obtained in exchange for new operating lease liabilities	$	5,152
Right-to-use asset obtained in exchange for new financing lease liabilities	$	48,224
Variable lease costs	$	—
Short term lease costs	$	—
Weighted-average remaining lease term-operating leases		8.7 years
Weighted-average remaining lease term-financing leases		19.3 years
Weighted-average discount rate-operating leases		7	%
Weighted-average discount rate-financing leases		8	%

Income taxes (Tables)

12 Months Ended

Mar. 31, 2020

Income taxes

Schedule of net loss before income taxes


	Year Ended March 31,
	2020		2019		2018
United States	$	(12,963)	$	(9,483)	$	(8,992)
Foreign (United Kingdom)		(39,662)		(21,351)		(10,710)
	$	(52,625)	$	(30,834)	$	(19,702)

Schedule of reconciliation of the U.S federal statutory income tax rate


	March 31,
	2020		2019		2018
U.S. Federal statutory income tax rate	(21.00)	%	(21.00)	%	(21.00)	%
State taxes, net of federal benefit	(1.6)		(1.5)		(2.6)
Research and development expenses	2.2		3.1		3.8
Remeasurement of deferred taxes as a result of tax reform	—		—		2.6
Foreign tax rate differential	2.8		2.4		2.2
Change in valuation allowance	16.0		15.5		14.0
Return to provision	1.9		0.4		—
Other	(0.3)		1.1		1.0
Effective income tax rate	0.00	%	0.00	%	0.00	%

Schedule of components of deferred tax assets and liabilities


	March 31,
	2020		2019
Deferred tax assets:
Foreign net operating loss carryforwards	$	9,092	$	4,079
Federal net operating loss carryforwards		2,450		2,223
State net operating loss carryforwards		1,054		684
Property, plant and equipment		5,499		—
Capitalized start-up costs		1,748		1,886
Stock compensation		2,526		573
Accrued expenses		341		1,793
Lease liability		8,705		—
Total deferred tax assets		31,415		11,238
Deferred tax liabilities:
Right-to-use asset		(13,998)		—
Property, plant and equipment		—		(1,842)
Other		(88)		—
Total deferred tax liabilities		(14,086)		(1,842)
Valuation allowance		(17,329)		(9,396)
Net deferred tax assets	$	—	$	—

Schedule of valuation allowance for deferred tax assets


	March 31,
	2020		2019
Valuation allowance as of beginning of year	$	9,396	$	4,724
Increases recorded to income tax provision		8,047		4,672
Decreases recorded to income tax provision for equity		(114)		—
Valuation allowance as of end of year	$	17,329	$	9,396

Geographic information (Tables)

12 Months Ended

Mar. 31, 2020

Geographic information

Summary of company's long-lived assets held in different geographic regions


	March 31,
	2020		2019
United States	$	6,357		11,648
United Kingdom		503		511
	$	6,860	$	12,159

Quarterly financial data (unaudited) (Tables)

12 Months Ended

Mar. 31, 2020

Quarterly financial data (unaudited)

Schedule of Quarterly financial information


	Three Months Ended
	March 31, 2020	December 31, 2019	September 30, 2019	June 30, 2019
Operating expenses	16,385	16,664	12,242	10,907
Net loss attributable to common stockholders	(15,789)	(16,189)	(11,139)	(9,508)
Net loss per share attributable to common
stockholders, basic and diluted	(0.41)	(0.46)	(0.35)	(0.30)


	Three Months Ended
	March 31, 2019	December 31, 2018	September 30, 2018	June 30, 2018
Operating expenses	7,826	10,137	7,104	5,879
Net loss attributable to common stockholders	(6,656)	(7,673)	(6,461)	(10,044)
Net loss per share attributable to common
stockholders, basic and diluted	(0.29)	(0.24)	(0.26)	(2.02)

Nature of the business (Details) $ / shares in Units, $ in Thousands					1 Months Ended	3 Months Ended								12 Months Ended
	Jul. 30, 2018 USD ($) $ / shares shares	Jul. 24, 2018 USD ($) $ / shares shares	Jul. 09, 2018 shares	Jul. 10, 2017	Dec. 31, 2019 USD ($)	Mar. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2020 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) $ / shares shares	Mar. 31, 2018 USD ($)	Jul. 31, 2018 $ / shares
Shares issued in exchange of shares in Replimune Group, Inc				1
Ratio of replacement warrants to capital stock				1
Forward stock split ratio for each common stock			0.100534
Common stock, authorized \| shares			27,314,288			150,000,000				150,000,000				150,000,000	150,000,000
Proceeds from issuance of common stock in initial public offering, net of underwriting fees and discounts															$ 103,341
Issuance costs and underwriter fees														$ 355	$ 2,157
Repurchase of class A common stock upon closing of initial public offering (in shares) \| shares		26,258
Common stock, par value (in dollars per share) \| $ / shares						$ 0.001				$ 0.001				$ 0.001	$ 0.001
Net loss						$ (15,789)	$ (16,189)	$ (11,139)	$ (9,508)	$ (6,656)	$ (7,673)	$ (6,461)	$ (10,044)	$ (52,625)	$ (30,834)	$ (19,702)
Accumulated deficit						$ (112,298)				$ (59,766)				$ (112,298)	$ (59,766)
Initial public offering
Common stock, authorized \| shares		150,000,000
Shares issued \| shares		6,700,000
Shares issued price (in dollars per share) \| $ / shares		$ 15.00															$ 15.00
Proceeds from issuance of common stock in initial public offering, net of underwriting fees and discounts		$ 93,465
Issuance costs and underwriter fees		$ 2,157
Common stock, par value (in dollars per share) \| $ / shares		$ 0.001
Undesignated preferred stock, authorized \| shares		10,000,000
Preferred stock, Par Value (in dollars per share) \| $ / shares		$ 0.001
Underwriter rights
Shares issued \| shares	707,936
Shares issued price (in dollars per share) \| $ / shares	$ 15.00
Proceeds from issuance of common stock in initial public offering, net of underwriting fees and discounts	$ 9,876
Issuance costs and underwriter fees					$ 5,814

Summary of significant accounting policies (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Summary of significant accounting policies
Cash equivalents	$ 36,712	$ 10,664
Restricted cash	1,636	1,186
Deferred offering costs		2,157
Research and Development Incentives Income	3,084	2,528	$ 2,267
Research and Development Incentives Receivable, Current	2,962	2,474
Foreign currency translation gain (loss)	(236)	(897)	2,376
Net unrealized gain (loss) on short-term investments, net of tax	$ 309	80	$ (65)
Minimum percentage of benefit recognized is being realized upon ultimate settlement	50.00%
Office equipment
Summary of significant accounting policies
Property, Plant and Equipment, Useful Life	5 years
Computer equipment
Summary of significant accounting policies
Property, Plant and Equipment, Useful Life	3 years
Plant, plant and laboratory equipment
Summary of significant accounting policies
Property, Plant and Equipment, Useful Life	5 years
Leasehold improvements
Summary of significant accounting policies
Property, Plant and Equipment, Useful Life	10 years
United Kingdom \| Maximum
Summary of significant accounting policies
Percentage of qualifying research and development expenses reimbursed by government	14.50%
Operating Lease [Member]
Summary of significant accounting policies
Restricted cash	$ 1,636	$ 1,186

Summary of significant accounting policies - ASU 2016-02 (Details) - USD ($) $ in Thousands	Apr. 01, 2019	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019
Recently Adopted Accounting Pronouncements
Lease, Practical Expedients, Package	true
Right-to-use liability		$ 4,610	$ 4,363
Property, plant and equipment, net		6,860		$ 12,159
Right-to-use asset		4,425
Lease liabilities, current		873
Lease liabilities, non-current		3,737
Accrued expenses		5,156		2,801
Deferred rent, net of current portion				24
Financing obligation				(6,561)
Accumulated deficit		$ (112,298)		$ (59,766)
ASU 2016-02
Recently Adopted Accounting Pronouncements
Right-to-use liability	$ 837
Property, plant and equipment, net	645
Right-to-use asset	789
Long term prepaid rent	5,006
Lease liabilities, current	388
Lease liabilities, non-current	449
Accrued expenses	2,777
Accumulated deficit	(59,673)
ASU 2016-02 \| Adjustments
Recently Adopted Accounting Pronouncements
Property, plant and equipment, net	(11,514)
Right-to-use asset	789
Long term prepaid rent	5,006
Lease liabilities, current	388
Lease liabilities, non-current	449
Accrued expenses	(24)
Deferred rent, net of current portion	(24)
Financing obligation	6,561
Accumulated deficit	$ 93

Fair value of financial assets and liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Fair value of financial assets and liabilities
Transfer from Leve 1 to Level 2, assets	$ 0	$ 0
Transfer from Leve 2 to Level 1, assets	0	0
Transfers into Level 3, assets	0	0
Transfer out of Level 3, assets	0	0
Transfer from Leve 1 to Level 2, liabilities	0	0
Transfer from Leve 2 to Level 1, liabilities	0	0
Transfers into Level 3, liabilities	0	0
Transfer out of Level 3, liabilities	0	0
Recurring
Fair value of financial assets and liabilities
Assets fair value	145,767	119,771
Level 2 \| Recurring
Fair value of financial assets and liabilities
Assets fair value	145,767	119,771
Money market funds \| Recurring
Fair value of financial assets and liabilities
Assets fair value	36,712	2,676
Money market funds \| Level 2 \| Recurring
Fair value of financial assets and liabilities
Assets fair value	36,712	2,676
Commercial paper \| Recurring
Fair value of financial assets and liabilities
Assets fair value	21,884	46,687
Commercial paper \| Level 2 \| Recurring
Fair value of financial assets and liabilities
Assets fair value	21,884	46,687
US Government Agency bonds \| Recurring
Fair value of financial assets and liabilities
Assets fair value	15,295	20,884
US Government Agency bonds \| Level 2 \| Recurring
Fair value of financial assets and liabilities
Assets fair value	15,295	20,884
US Treasury bonds \| Recurring
Fair value of financial assets and liabilities
Assets fair value	35,810	41,057
US Treasury bonds \| Level 2 \| Recurring
Fair value of financial assets and liabilities
Assets fair value	35,810	41,057
Corporate debt securities \| Recurring
Fair value of financial assets and liabilities
Assets fair value	36,066	8,467
Corporate debt securities \| Level 2 \| Recurring
Fair value of financial assets and liabilities
Assets fair value	$ 36,066	$ 8,467

Fair value of financial assets and liabilities - Unobservable inputs of the warrant liability (Details)	Mar. 31, 2019 $ / shares	Jul. 31, 2018 $ / shares	Jul. 24, 2018 $ / shares
Initial public offering
Unobservable inputs of the warrant liability
Fair value of series seed preferred stock (in price per share)		$ 15.00	$ 15.00
Risk-free interest rate
Unobservable inputs of the warrant liability
Warrant liability inputs	2.81
Expected term
Unobservable inputs of the warrant liability
Warrant liability expected term (in years)	7 years 2 months 12 days
Expected volatility
Unobservable inputs of the warrant liability
Warrant liability inputs	64.4
Expected dividend yield
Unobservable inputs of the warrant liability
Warrant liability inputs	0
Fair value of series seed preferred stock
Unobservable inputs of the warrant liability
Warrant liability inputs	15.00

Fair value of financial assets and liabilities - Roll forward of the warrant liability (Details) - Warrants to purchase convertible preferred stock $ in Thousands	12 Months Ended
	Mar. 31, 2019 USD ($)
Roll forward of the warrant liability
Balance at beginning of the period	$ 1,642
Change in fair value	5,452
Conversion of convertible preferred stock warrant into common stock warrant	$ (7,094)

Short-term investments (Details) - Short-term investments - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Short-term investments
Amortized cost	$ 108,732	$ 109,092
Gross unrealized gains	388	19
Gross unrealized losses	(65)	(4)
Fair value	109,055	109,107
Commercial paper
Short-term investments
Amortized cost	21,818	46,687
Gross unrealized gains	66	2
Gross unrealized losses		(2)
Fair value	21,884	46,687
US Government Agency bonds
Short-term investments
Amortized cost	15,217	15,889
Gross unrealized gains	78	4
Fair value	15,295	15,893
US Treasury bonds
Short-term investments
Amortized cost	35,590	38,047
Gross unrealized gains	220	13
Fair value	35,810	38,060
Corporate debt securities
Short-term investments
Amortized cost	36,107	8,469
Gross unrealized gains	24
Gross unrealized losses	(65)	(2)
Fair value	$ 36,066	$ 8,467

Property, plant and equipment, net (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2019	Apr. 01, 2019
Property, plant and equipment, net
Property, plant and equipment , gross	$ 7,797	$ 12,563
Less: Accumulated depreciation and amortization	(937)	(404)
Property, plant and equipment , net	6,860	12,159
Depreciation and amortization expense	533	148	$ 109
Financing obligation		(6,561)
ASU 2016-02
Property, plant and equipment, net
Property, plant and equipment , net					$ 645
Long term prepaid rent					5,006
ASU 2016-02 \| Adjustments
Property, plant and equipment, net
Property, plant and equipment , net					(11,514)
Financing obligation					6,561
Long term prepaid rent					5,006
Construction in progress
Property, plant and equipment, net
Property, plant and equipment , gross	1,217	124
Plant and laboratory equipment
Property, plant and equipment, net
Property, plant and equipment , gross	3,669	584
Leasehold improvements
Property, plant and equipment, net
Property, plant and equipment , gross	532	154
Computer equipment
Property, plant and equipment, net
Property, plant and equipment , gross	1,658	138
Office equipment
Property, plant and equipment, net
Property, plant and equipment , gross	$ 721	49
Build-to-suit lease asset
Property, plant and equipment, net
Property, plant and equipment , gross		$ 11,514		$ 11,514
Build-to-suit lease asset \| ASU 2016-02
Property, plant and equipment, net
Property, plant and equipment , net					$ 11,514

Accrued expenses and other current liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Accrued expenses and other current liabilities
Accrued research and development costs	$ 2,009	$ 530
Accrued compensation and benefits costs	2,065	1,510
Accrued professional fees	779	464
Deferred rent		24
Other	303	273
Total	$ 5,156	$ 2,801

Long-term debt (Details) $ in Thousands	Mar. 31, 2020 USD ($)
Long-term debt
Principal amount of long-term debt	$ 10,000
Unamortized debt discount	(199)
Long-term debt, net of discount	$ 9,801

Long-term debt - Hercules Loan Agreement (Details) $ in Thousands		1 Months Ended	3 Months Ended	8 Months Ended	12 Months Ended
	Aug. 08, 2019 USD ($) item	Aug. 31, 2019 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)
Debt Securities
Interest expense					$ 734
Unamortized debt discount			$ 199	$ 199	199
Long Term Debt Due Charges			495
Hercules Loan Agreement
Debt Securities
Maximum borrowing capacity	$ 30,000
Borrowed amount	10,000
Facility charge	225
Additional closing and legal fees	130
Unused borrowing capacity available under the facility	$ 20,000
Number of separate advances available to be borrowed under the unused facility \| item	2
Interest rate		8.75%
Term (in years)		4 years
Percentage of prepayment charge payable within the first twelve months		3.00%
Percentage of prepayment charge payable after twelve months but prior to twenty four months		2.00%
Percentage of prepayment charge payable anytime thereafter		1.00%
Percentage of charge Payable on aggregate debt amount		4.95%
Upfront fees, including closing costs and legal fees		$ 355
Interest expense					734
Non-cash interest expense related to accretion of the debt discount					60	$ 96
Unamortized debt discount			199	$ 199	199
Interest Rate				10.10%
Principal payments due or paid			$ 0	$ 0	$ 0
Hercules loan agreement, second advance
Debt Securities
Maximum borrowing capacity	$ 10,000
Hercules loan agreement, third advance
Debt Securities
Maximum borrowing capacity	$ 10,000
Prime Rate \| Hercules Loan Agreement
Debt Securities
Variable interest rate		2.75%

Long-term debt - Future payments of long-term debt (Details) $ in Thousands	Mar. 31, 2020 USD ($)
Long-term debt
2022	$ 527
2023	6,558
2024	2,915
Total debt payments	$ 10,000

Stockholders' Equity (Details) - $ / shares	Mar. 31, 2020	Mar. 31, 2019	Jul. 24, 2018	Jul. 09, 2018
Stockholders' Equity
Shares authorized (in shares)	150,000,000	150,000,000		27,314,288
Par value (in dollars per share)	$ 0.001	$ 0.001
Initial public offering
Stockholders' Equity
Shares authorized (in shares)			150,000,000
Par value (in dollars per share)			$ 0.001
Undesignated preferred stock, authorized			10,000,000
Preferred stock, Par Value (in dollars per share)			$ 0.001
Common stock
Stockholders' Equity
Common stock reserved for the conversion of outstanding shares of preferred stock	10,449,033	6,873,744
Undesignated preferred stock \| Initial public offering
Stockholders' Equity
Undesignated preferred stock, authorized	10,000,000
Preferred stock, Par Value (in dollars per share)	$ 0.001
Undesignated preferred shares issued	0
Undesignated preferred shares outstanding	0

Stockholders' Equity - Convertible preferred stock (Details) $ in Thousands			12 Months Ended
	Jul. 25, 2018 shares	Jul. 09, 2018	Mar. 31, 2019 USD ($) shares	Mar. 31, 2020 USD ($)
Convertible preferred stock
Forward stock split ratio for each common stock		0.100534
Convertible preferred stock
Convertible preferred stock
Conversion of shares (in shares) \| shares	19,157,360		(1,925,968)
Forward stock split ratio for each common stock		0.100534
Preferred stock outstanding \| $			$ 0	$ 0

Stockholders' Equity - Preferred stock warrants (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jul. 24, 2019	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2020
Preferred stock warrants
Loss from change in fair value of the warrant liability		$ (5,452)	$ (972)
Series seed preferred stock
Preferred stock warrants
Number of preferred stock warrants issued				50,000
Exercise price (in dollars per share)				$ 10.00
Fair value of the warrants to purchase shares of series seed preferred stock				$ 391
Preferred stock warrants, exercisable	497,344
Other income (expense), net
Preferred stock warrants
Loss from change in fair value of the warrant liability		$ (5,452)	$ (972)

Stockholders' Equity - ATM program (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended		12 Months Ended
	Aug. 08, 2019	Dec. 31, 2019	Aug. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Class of Warrant or Right [Line Items]
Common stock, par value (in dollars per share)				$ 0.001	$ 0.001
Net proceeds		$ 85,598
ATM sales
Class of Warrant or Right [Line Items]
Issuance of stock (value)				$ 4,431
Common stock, par value (in dollars per share)			$ 0.001
Percentage Of Commission			3.00%
Common stock sold				287,559
Gross proceeds				$ 4,568
Legal fees				137
Net proceeds				$ 4,431
ATM sales \| Maximum
Class of Warrant or Right [Line Items]
Issuance of stock (value)			$ 75,000
Securities offered to the public during the period	$ 250,000

Stockholders' Equity - Equity offerings (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		12 Months Ended
	Dec. 31, 2019	Nov. 30, 2019	Mar. 31, 2020	Mar. 31, 2019
Class of Warrant or Right [Line Items]
Public offering price		$ 13.61
Variation between public offering prices of common stock and pre-funded warrants		$ 0.0001
Net proceeds from sale of stock	$ 85,598
Issuance costs and underwriter fees			$ 355	$ 2,157
Pre-Funded Warrants
Class of Warrant or Right [Line Items]
Issuance of pre-funded warrants		2,200,000
Pre-funded warrants exercise price		$ 13.6099
Maximum percentage of holding for exercise warrants		9.99%
Prior notice period to change percentage of holding		61 days
Underwriter rights
Class of Warrant or Right [Line Items]
Common stock sold	838,530	3,678,031
Number of days for purchase shares		30 days
Maximum additional shares to purchase		881,704
Issuance costs and underwriter fees	$ 5,814

Stock-based compensation (Details) - shares			12 Months Ended
Stock-based compensation (Details) - shares	Apr. 01, 2019	Jul. 09, 2018	Mar. 31, 2020	Jul. 31, 2017
2017 Plan
Share based payments
Shares authorized (in shares)				2,659,885
Number of shares available for grant			0
2017 Plan \| Maximum
Share based payments
Number of shares available for grant		2,520,247
2018 Plan
Share based payments
Shares authorized (in shares)		3,617,968
Number of shares available for grant			2,122,012
Additional shares authorized (in shares)	1,266,278
ESPP
Share based payments
Additional shares authorized (in shares)	316,569	697,224
Common stock reserved for issuance	665,181	348,612
Share based payment award percentage of outstanding shares		1.00%
Employees stock options
Share based payments
Exercise price for persons holding ten percent of voting power (as a percent)			100.00%
Exercise price for persons holding more than ten percent of voting power (as a percent)			110.00%
Share based payment award expiration period			10 years
Share based payment award vesting period			4 years
Employees stock options \| Minimum
Share based payments
Expiration period for persons holding more than ten percent of voting power			10 years
Employees stock options \| Maximum
Share based payments
Expiration period for persons holding ten percent of voting power			5 years

Stock-based compensation - Assumptions to determine grant-date fair value of stock options (Details) - shares	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Stock-based Compensation
Granted (in shares)			1,637,035
Employees stock options
Stock-based Compensation
Risk-free interest rate			2.12%	2.81%	2.01%
Expected term (in years)			6 years	6 years 1 month 6 days	6 years
Expected volatility			71.40%	62.00%	75.00%
Expected dividend yield			0.00%	0.00%	0.00%
Non Employee Stock Option Member
Stock-based Compensation
Risk-free interest rate					2.29%
Expected term (in years)					10 years
Expected volatility					75.00%
Expected dividend yield					0.00%
Granted (in shares)	0	0

Stock-based compensation - Stock option activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Number of Shares
Outstanding at beginning of the period (in shares)	3,721,784
Granted (in shares)	1,637,035
Exercised (in shares)	(207,673)
Cancelled (in shares)	(186,765)
Outstanding at end of the period (in shares)	4,964,381	3,721,784
Options exercisable (in shares)	2,117,721	1,278,330
Weighted Average Exercise Price
Outstanding at beginning of the period (in dollars per share)	$ 7.14
Granted (in dollars per share)	15.07
Exercised (in dollars per share)	2.65
Cancelled (in dollars per share)	11.48
Outstanding at end of the period (in dollars per share)	9.78	$ 7.14
Options exercisable (in dollars per share)	$ 5.66	$ 2.51
Weighted Average Contractual Term (Years)
Outstanding (years)	8 years 7 days	8 years 7 months 10 days
Granted (years)	9 years 2 months 16 days
Options exercisable (years)	7 years 2 months 12 days	7 years 9 months
Aggregate Intrinsic Value
Outstanding at beginning of the period	$ 30,150
Outstanding at end of the period	15,344	$ 30,150
Options exercisable	$ 11,733	$ 16,249
Weighted average grant-date fair value per share of stock options granted	$ 9.70	$ 8.82
Total fair value of options vested	$ 5,440	$ 1,298
Outstanding unvested service-based stock options	0

Stock-based compensation - Classification of expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Share-Based Compensation
Total share based compensation expense	$ 7,741	$ 2,730	$ 812
Total unrecognized compensation cost	$ 18,732
Expenses expected to be recognized over a weighted average remaining period	2 years 6 months 22 days
Research and development expenses
Share-Based Compensation
Total share based compensation expense	$ 3,689	1,488	335
General and administrative expenses
Share-Based Compensation
Total share based compensation expense	$ 4,052	$ 1,242	$ 477

Net loss per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Numerator:
Net loss attributable to common stockholders									$ (52,625)	$ (30,834)	$ (19,702)
Denominator:
Weighted average common shares outstanding, basic and diluted (in shares)									34,261,548	23,198,400	4,978,539
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.41)	$ (0.46)	$ (0.35)	$ (0.30)	$ (0.29)	$ (0.24)	$ (0.26)	$ (2.02)	$ (1.54)	$ (1.33)	$ (3.96)

Net loss per share - Computation of diluted net loss per share attributable to common stockholders (Details) - shares	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Diluted net loss per share attributable to common stockholders
Antidilutive securities excluded from computation of diluted weighted average shares outstanding	5,461,725	4,219,128	22,174,951
Options to purchase common stock
Diluted net loss per share attributable to common stockholders
Antidilutive securities excluded from computation of diluted weighted average shares outstanding	4,964,381	3,721,784	2,520,247
Convertible preferred stock
Diluted net loss per share attributable to common stockholders
Antidilutive securities excluded from computation of diluted weighted average shares outstanding			19,157,360
Warrants to purchase convertible preferred stock
Diluted net loss per share attributable to common stockholders
Antidilutive securities excluded from computation of diluted weighted average shares outstanding	497,344	497,344	497,344

Significant agreements (Details) $ in Thousands	1 Months Ended
Significant agreements (Details) $ in Thousands	Jan. 31, 2020 item	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)
Significant agreements
Prepaid expenses and other current assets		$ 2,734	$ 3,696
Regeneron Pharmaceuticals, Inc
Significant agreements
Prepaid expenses and other current assets		$ 971	$ 337
Bristol-Myers Squibb Company
Significant agreements
Number Of Patients \| item	125

Commitments and contingencies - Lease agreements (Details) $ in Thousands			1 Months Ended				8 Months Ended	12 Months Ended	28 Months Ended
	Oct. 22, 2019 USD ($) ft²	Aug. 01, 2019 USD ($) ft²	Jun. 30, 2019 USD ($) ft²	Jun. 30, 2018 USD ($) ft² Option	Apr. 30, 2016	Dec. 31, 2015 USD ($)	Dec. 03, 2016 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Apr. 01, 2019 USD ($)
Lease agreements
Number of options to extend lease agreement (in years)						5 years
Monthly lease payments, inclusive of base rent and ancillary charges						$ 7
Prior notice period upon termination of lease					9 months
Base rent of monthly lease payments							$ 23		$ 31
Reclassified from prepaid rent	$ 18,164	$ 2,368
Leased office space \| ft²	53,000	10,500	18,700	63,000
Prepaid Rent	$ 261
Lease term			10 years	10 years
Number of options to renewal the lease \| Option				2
Renewal period of lease			5 years	5 years
Annual rental payment			$ 488	$ 2,373
Percentage of annual increase in lease rental expenses			1.60%	3.00%
Property, plant and equipment, net								$ 6,860	12,159
Financing obligation									$ (6,561)
Right-to-use asset								4,425
Right-to-use liability			$ 4,363					4,610
ASU 2016-02
Lease agreements
Property, plant and equipment, net										$ 645
Long term prepaid rent										5,006
Right-to-use asset										789
Right-to-use liability										837
ASU 2016-02 \| Adjustments
Lease agreements
Property, plant and equipment, net										(11,514)
Financing obligation										6,561
Long term prepaid rent										5,006
Right-to-use asset										789
General and administrative expenses
Lease agreements
Finance Lease Cost								239
Research and development expenses
Lease agreements
Finance Lease Cost								$ 1,034
Build-to-suit lease asset \| ASU 2016-02
Lease agreements
Property, plant and equipment, net										$ 11,514

Commitments and contingencies - Components of lease expense (Details) $ in Thousands	12 Months Ended
	Mar. 31, 2020 USD ($)
Finance lease costs:
Amortization of right-of-use asset	$ 1,274
Interest on lease liabilities	1,185
Operating lease costs	885
Total lease cost	$ 3,344

Commitments and contingencies - Future lease payments under operating and financing lease liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Jun. 30, 2019
Operating leases
2021	$ 873
2022	586
2023	596
2024	605
2025	614
Thereafter	2,791
Total lease payments	6,065
Less: interest	1,455
Total lease liabilities	4,610	$ 4,363
Financing lease
2021	2,411
2022	2,483
2023	2,558
2024	2,634
2025	2,714
Thereafter	43,685
Total lease payments	56,485
Less: interest	29,107
Total lease liabilities	27,378
Total
2021	3,284
2022	3,069
2023	3,154
2024	3,239
2025	3,328
Thereafter	46,476
Total lease payments	62,550
Less: interest	30,562
Total lease liabilities	$ 31,988

Commitments and contingencies - Future annual minimum lease payment commitments (Details) $ in Thousands	Mar. 31, 2020 USD ($)
Future annual minimum lease payment commitments:
2020	$ 2,062
2021	2,901
2022	2,493
2023	2,568
2024	2,645
2025	2,725
Thereafter	12,770
Total	$ 28,164

Commitments and contingencies - Additional information related to leases (Details) $ in Thousands	12 Months Ended
	Mar. 31, 2020 USD ($)
Leases
Right-to-use operating lease asset	$ 4,425
Right-to-use financing lease asset	46,925
Total lease assets	51,350
Operating lease liabilities, current	873
Finance lease liabilities, current	2,411
Operating lease liabilities, non-current	3,737
Finance lease liabilities, non-current	24,967
Total lease liabilities	31,988
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	747
Operating cash flows from finance leases	1,185
Financing cash flows from finance leases	59
Right-to-use asset obtained in exchange for new operating lease liabilities	5,152
Right-to-use asset obtained in exchange for new financing lease liabilities	$ 48,224
Weighted-average remaining lease term - operating leases	8 years 8 months 12 days
Weighted-average remaining lease term - financing leases	19 years 3 months 18 days
Weighted-average discount rate - operating leases	7.00%
Weighted-average discount rate - financing leases	8.00%

Commitments and contingencies - Manufacturing commitments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Commitments and contingencies
Minimum payments committed to manufacturing organization	$ 3,569	$ 4,694

Benefit plans (Details) - USD ($) $ in Thousands	12 Months Ended
Benefit plans (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
401(k) Plan
Benefit Plans
Contributions to the plan	$ 232	$ 102	$ 49
Pension Plan
Benefit Plans
Maximum percentage of contribution by employee of their annual base salary	8.00%

Income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Income taxes (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Income Taxes
Income tax benefit	$ 0	$ 0	$ 0
Net loss before income taxes
United States	(12,963)	(9,483)	(8,992)
Foreign (United Kingdom)	(39,662)	(21,351)	(10,710)
Net loss before income taxes	$ (52,625)	$ (30,834)	$ (19,702)

Income taxes - Reconciliation of the U.S federal statutory income tax rate (Details)	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Reconciliation of the U.S federal statutory income tax rate
U.S. Federal statutory income tax rate	(21.00%)	(21.00%)	(21.00%)
State taxes, net of federal benefit	(1.60%)	(1.50%)	(2.60%)
Research and development expenses	2.20%	3.10%	3.80%
Remeasurement of deferred taxes as a result of tax reform			2.60%
Foreign tax rate differential	2.80%	2.40%	2.20%
Change in valuation allowance	16.00%	15.50%	14.00%
Return to provision	1.90%	0.40%
Other	(0.30%)	1.10%	1.00%
Effective income tax rate	0.00%	0.00%	0.00%

Income taxes - Components of deferred tax assets and liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Deferred tax assets:
Foreign net operating loss carryforwards	$ 9,092	$ 4,079
Federal net operating loss carryforwards	2,450	2,223
State net operating loss carryforwards	1,054	684
Property, plant and equipment	5,499
Capitalized start-up costs	1,748	1,886
Stock compensation	2,526	573
Accrued expenses	341	1,793
Lease liability	8,705
Total deferred tax assets	31,415	11,238
Deferred tax liabilities:
Right-to-use asset	(13,998)
Property, plant and equipment		(1,842)
Other	(88)
Total deferred tax liabilities	(14,086)	(1,842)
Valuation allowance	(17,329)	$ (9,396)	$ (4,724)
Deferred tax assets operating loss carryforwards
Federal net operating loss carryforwards having indefinite expiration period	11,667
Foreign net operating loss carryforwards having indefinite expiration period	53,483
State net operating loss carryforwards, expires between 2039 and 2040	$ 16,670

Income taxes - Valuation allowance for deferred tax assets (Details)	12 Months Ended
	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)
Deferred tax assets, Valuation allowance
Valuation allowance as of beginning of year	$ 9,396,000	$ 4,724,000
Increases recorded to income tax provision	8,047,000	4,672,000
Decrease recorded to income tax provision for equity	(114,000)
Valuation allowance as of end of year	17,329,000	9,396,000	$ 4,724,000
Accrued interest or penalties related to uncertain tax positions	0	0
Income tax benefit	$ 0	$ 0	$ 0
Number of pending tax examination	0

Geographic information (Details) $ in Thousands	12 Months Ended
Geographic information (Details) $ in Thousands	Mar. 31, 2020 USD ($) item	Mar. 31, 2019 USD ($)
Geographic information
Number of operating geographic regions \| item	2
Long-lived assets	$ 6,860	$ 12,159
United States
Geographic information
Long-lived assets	6,357	11,648
United Kingdom
Geographic information
Long-lived assets	$ 503	$ 511

Quarterly financial data (unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Quarterly financial data (unaudited)
Operating expenses	$ 16,385	$ 16,664	$ 12,242	$ 10,907	$ 7,826	$ 10,137	$ 7,104	$ 5,879	$ 56,198	$ 30,946	$ 19,229
Net loss attributable to common stockholders	$ (15,789)	$ (16,189)	$ (11,139)	$ (9,508)	$ (6,656)	$ (7,673)	$ (6,461)	$ (10,044)	$ (52,625)	$ (30,834)	$ (19,702)
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.41)	$ (0.46)	$ (0.35)	$ (0.30)	$ (0.29)	$ (0.24)	$ (0.26)	$ (2.02)	$ (1.54)	$ (1.33)	$ (3.96)

- Definition

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

+ References + Details

Subsequent events (Details) - USD ($) $ in Thousands	Jun. 01, 2020	May 31, 2020	Aug. 08, 2019
Hercules Loan Agreement
Subsequent Event [Line Items]
Maximum borrowing capacity			$ 30,000
Hercules Loan Agreement \| Subsequent events
Subsequent Event [Line Items]
Maximum borrowing capacity	$ 40,000	$ 30,000
Hercules Loan Agreement, fourth advance \| Subsequent events
Subsequent Event [Line Items]
Maximum borrowing capacity	$ 10,000