0001737953-24-000008 | 10-K | XBRL Viewer

Commitments and contingencies (Tables)

12 Months Ended

Mar. 31, 2024

Commitments and Contingencies Disclosure [Abstract]

The table below presents the lease-related costs which are included in the consolidated statements of operations for the years ended as of March 31, 2024 and 2023:


	Year ended March 31,
	2024		2023
Lease cost
Finance lease costs:
Amortization of right-to-use asset	$	2,428	$	2,428
Interest on lease liabilities	2,163		2,197
Operating lease costs	1,122		1,018
Total lease cost	$	5,713	$	5,643

The following table summarizes the classification of lease costs in the consolidated statement of operations for the years ended March 31, 2024 and 2023 as follows:


	Year ended March 31,
	2024		2023
Finance Lease Costs
Research and development	$	2,428	$	2,071
Selling, general and administrative	—		358
Other income, net	2,163		2,197
Operating Lease Costs
Research and development	911		421
Selling, general and administrative	211		596
Total lease cost	$	5,713	$	5,643

Summary of the maturity of company's lease liabilities

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, 2024:


	March 31, 2024
	Operating leases		Financing lease		Total
2025	$	1,161	$	2,718	$	3,879
2026	1,170		2,799		3,969
2027	1,136		2,883		4,019
2028	1,085		2,969		4,054
2029	1,004		3,058		4,062
Thereafter	923		31,995		32,918
Total lease payments	6,479		46,422		52,901
Less: interest	1,547		20,294		21,841
Total lease liabilities	$	4,932	$	26,128	$	31,060

Schedule of additional information related to leases

The following table provides lease disclosure as of and for the year ended March 31, 2024:


	March 31, 2024			March 31, 2023
Leases
Right-to-use operating lease asset	$	4,635		$	5,208
Right-to-use finance lease asset	37,237			39,665
Total lease assets	$	41,872		$	44,873
Operating lease liabilities, current	$	1,161		$	1,118
Finance lease liabilities, current	2,718			2,639
Operating lease liabilities, non-current	3,771			4,389
Finance lease liabilities, non-current	23,410			23,965
Total lease liabilities	$	31,060		$	32,111
Other information
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	1,059		$	1,014
Operating cash flows from finance leases	$	2,163		$	2,197
Financing cash flows from finance leases	$	476		$	365
Right-to-use asset obtained in exchange for new operating lease liabilities	$	—		$	290
Weighted-average remaining lease term – operating leases	5.6 years			6.6 years
Weighted-average remaining lease term – financing leases	15.3 years			16.3 years
Weighted-average discount rate – operating leases	10.3		%	10.3		%
Weighted-average discount rate – financing leases	8.3		%	8.3		%

Stockholders' equity - ATM Program (Details) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended	12 Months Ended
	Aug. 03, 2023	Jun. 23, 2022	Aug. 11, 2020	Dec. 31, 2022	Mar. 31, 2024	Mar. 31, 2023
Class of Warrant or Right [Line Items]
Gross proceeds				$ 242,600	$ 0	$ 149,854
Common stock, par value (in dollars per share)					$ 0.001	$ 0.001
Common stock
Class of Warrant or Right [Line Items]
Shares issued during period (in shares)						6,810,658
ATM sales
Class of Warrant or Right [Line Items]
Shares issued during period (in shares)					340,000
Gross proceeds					$ 6,700
Issuance costs and underwriter fees					300
Commission percentage			3.00%
ATM sales \| Common stock
Class of Warrant or Right [Line Items]
Aggregate offering amount					$ 32,000
Number of shares issued (in shares)					1,686,438
Underwriting discounts, commissions and other offering expenses					$ 1,000
Maximum received on transactions	$ 100,000	$ 100,000
Shares issued during period (in shares)						2,026,438
Common stock, par value (in dollars per share)	$ 0.001
ATM sales \| Common stock \| Maximum
Class of Warrant or Right [Line Items]
Aggregate offering amount			$ 62,500

Fair value of financial assets and liabilities (Tables)

12 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

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

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, 2024 Using:
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	—	$	41,077	$	—	$	41,077
Short-term investments:
US Government Agency bonds	—		199,821		—		199,821
US Treasury bonds	—		146,390		—		146,390
	$	—	$	387,288	$	—	$	387,288


	Fair Value Measurements as of March 31, 2023 Using:
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	—	$	121,455	$	—	$	121,455
Short-term investments:
US Government Agency bonds	—		240,355		—		240,355
US Treasury bonds	—		196,441		—		196,441
	$	—	$	558,251	$	—	$	558,251

Stockholders' equity - Common Stock and Undesignated Preferred Stock (Details) - $ / shares	Mar. 31, 2024	Mar. 31, 2023
Stockholders' Equity Note [Abstract]
Common stock, authorized (in shares)	150,000,000	150,000,000
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Undesignated preferred stock, authorized (in shares)	10,000,000	10,000,000
Preferred stock, Par Value (in dollars per share)	$ 0.001	$ 0.001
Undesignated preferred shares issued (in shares)	0	0
Undesignated preferred shares outstanding	0	0

Summary of significant accounting policies (Policies)

12 Months Ended

Mar. 31, 2024

Accounting Policies [Abstract]

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 direct and indirect wholly owned subsidiaries, Replimune UK, Replimune US, Replimune Securities Corporation and Replimune (Ireland) Limited after elimination of all intercompany accounts and transactions.

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 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.

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 stockholders’ equity as a component of accumulated other comprehensive income (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. We limit our exposure to credit risk by placing investments with high credit quality financial institutions, diversifying our investment portfolio and placing investments with maturities that maintain safety and liquidity. To date, the Company has not experienced any losses on such accounts.

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

Restricted cash

The Company holds restricted cash in segregated bank accounts in connection with a letter of credit.

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 non-credit related losses reported as a component of accumulated other comprehensive income (loss) and included in stockholders’ equity. 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.

For available-for-sale debt securities in an unrealized loss position, we first assess whether we intend to sell, or if it is more likely than not that we will be required to sell, the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through a charge to interest income. For available-for-sale debt securities that do not meet the aforementioned criteria, we evaluate whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, the Company considers such factors as, among other things, the severity of the impairment, any changes in interest rates, 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. The credit-related portion of unrealized losses, and any subsequent improvements, are recorded in interest income through an allowance account. Any impairment that has not been recorded through an allowance for credit losses is included in other comprehensive loss on the statements of comprehensive loss.

No credit-related losses or impairments have been recognized on the Company's investments in available-for-sale debt securities during the years ended March 31, 2024 or 2023.

The Company’s short-term investments as of March 31, 2024 and 2023 had maturities of less than two years. The Company has classified its investments with maturities beyond one year as short term, based on their highly liquid nature and because they represent the investment of cash that is available for current operations.

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 and software			3 years
Plant, manufacturing and laboratory equipment			5 years
Capitalized software			3 to 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.

Capitalized software as a service costs represent implementation costs incurred during the application development stage and are included in "property, plant and equipment, net" on the Company's consolidated balance sheet. Such costs are amortized on a straight-line basis over the term of the associated arrangement plus any reasonably certain renewal period. Costs incurred during the preliminary project stage and the post-implementation-operation stage are expensed as incurred.

Impairment of long-lived assets

Long-lived assets consist of property, plant and equipment, right-to-use-asset - operating leases, and right-to-use-asset - financing leases. 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 and cash equivalents 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, prepaid expenses and 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. Furthermore, the carrying value of the Company’s long-term

debt approximates its fair value at each balance sheet date due to its variable interest rate, which approximates a market interest rate.

Debt Issuance Costs

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 cancellable, and related costs are recorded as research and development expenses as incurred. The Company records accruals for estimated ongoing research costs. Accrual estimates are based on a number of factors, including management’s assessment of progress towards completion of the research and development activities, invoicing to date under the contracts, communication from the research organization or other companies of any actual costs incurred during the period that have not yet been invoiced, and the costs included in the contracts. When billing terms under these contracts do not coincide with the timing of when the work is performed, management is required to make estimates of outstanding obligations to those third parties as of the end of the reporting period. 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 selling, general and administrative expenses.

Stock-based compensation

The Company accounts for share-based payment awards granted to employees, consultants, and non-employees and directors using the fair value of the Company’s common stock on the grant date and compensation expense is recognized for those awards over the requisite service period, which is generally the vesting period of the respective award. The grant date fair value is utilized for restricted stock units, or RSUs and performance stock units, or PSUs and is based on the closing price of the Company's common stock on the date of grant. For PSUs, the cost is measured at the grant date based on the fair value of the award and is recognized over any relevant service period as expense when the achievement of the performance condition is probable. 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 10). Forfeitures are accounted for as they occur. To date, the Company has issued stock-based awards with service-based vesting conditions and records the related expense for these awards using the straight-line method. The Company has also issued PSUs with performance-based vesting conditions and records the expense for these awards using the graded vesting 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.

Comprehensive loss

Comprehensive loss includes net loss as well as other changes in stockholders’ equity that result from transactions and economic events other than those with stockholders.

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 provision. 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

Basic net income (loss) per common share is computed by dividing the net income (loss) by the weighted average number of shares of common stock outstanding for the period. Diluted net income (loss) per common share is computed by dividing the diluted net income (loss) 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.

In periods in which the Company reports a net loss, diluted net loss per share is the same as basic net loss per share, since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive.

Recently adopted accounting pronouncements and Recently issued accounting pronouncements

Recently Issued Accounting Pronouncements

In December 2023, the Financial Accounting Standards Board issued Accounting Standards Update ("ASU") No. 2023-09, “Income Taxes (Topic 740): Improvements to Income Tax Disclosures.” This ASU updates income tax disclosure requirements primarily by requiring specific categories and greater disaggregation within the rate reconciliation and disaggregation of income taxes paid by jurisdiction. This ASU is effective for annual periods beginning after December 15, 2024 and is applicable to the Company’s fiscal year beginning April 1, 2025, with early application permitted. The Company is currently evaluating the impact of adopting this ASU on its consolidated financial statements and disclosures.

In November 2023, the FASB issued ASU 2023-07, "Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures". The amendments in this update expand segment disclosure requirements, including new segment disclosure requirements for entities with a single reportable segment among other disclosure requirements. This update is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. The Company is currently evaluating the potential impact of this adoption on the consolidated financial statements and related disclosures.

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	ATM sales	Common stock	Common stock ATM sales	Additional paid-in capital	Additional paid-in capital ATM sales	Accumulated deficit	Accumulated other comprehensive income (loss)
Balance (in shares) at Mar. 31, 2022			47,338,660
Balance at Mar. 31, 2022	$ 411,229		$ 47		$ 723,359		$ (311,204)	$ (973)
Increase (decrease) in Stockholders' Equity
Issuance of common stock, net of offering and issuance costs and underwriter fees (in shares)			6,810,658	2,026,438
Issuance of common stock, net of offering and issuance costs and underwriting fees	149,854	$ 37,438	$ 7	$ 2	149,847	$ 37,436
Issuance of prefunded warrants to purchase common stock	92,778				92,778
Foreign currency translation adjustment	5,483							5,483
Unrealized gain (loss) on short-term investments	1,219							1,219
Exercise of stock options (in shares)			296,876
Exercise of stock options	3,444		$ 1		3,443
Vesting of RSUs (in shares)			203,681
Stock-based compensation expense	28,131				28,131
Net loss	(174,284)						(174,284)
Balance (in shares) at Mar. 31, 2023			56,676,313
Balance at Mar. 31, 2023	555,292		$ 57		1,034,994		(485,488)	5,729
Increase (decrease) in Stockholders' Equity
Issuance of common stock, net of offering and issuance costs and underwriter fees (in shares)		340,000
Foreign currency translation adjustment	(826)							(826)
Unrealized gain (loss) on short-term investments	(48)							(48)
Exercise of pre-funded warrants (in shares)			4,202,622
Exercise of pre-funded warrants	$ 0		$ 4		(4)
Exercise of stock options (in shares)	164,221		164,221
Exercise of stock options	$ 1,759		$ 0		1,759
Vesting of RSUs (in shares)			371,949
Stock-based compensation expense	34,125				34,125
Net loss	(215,794)						(215,794)
Balance (in shares) at Mar. 31, 2024			61,415,105
Balance at Mar. 31, 2024	$ 374,508		$ 61		$ 1,070,874		$ (701,282)	$ 4,855

Geographic information (Tables)

12 Months Ended

Mar. 31, 2024

Segments, Geographical Areas [Abstract]

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

Information about the Company’s long-lived assets held in different geographic regions is presented in the tables below:


	March 31, 2024		March 31, 2023
United States	$	8,992	$	5,836
United Kingdom	1,491		1,643
	$	10,483	$	7,479

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash flows from operating activities:
Net loss	$ (215,794)	$ (174,284)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	34,125	28,131
Depreciation and amortization	2,655	2,447
Net amortization of premiums and discounts on short-term investments	(12,326)	(5,638)
Noncash interest expense	1,161	494
Unrealized foreign currency transaction losses	(771)	5,676
Changes in operating assets and liabilities:
Research and development incentives receivable	(1,916)	(61)
Prepaid expenses and other current assets	(1,778)	(1,059)
Operating lease, right-of-use-asset	615	225
Finance lease, right-of-use-asset	2,428	2,428
Accounts payable	(2,794)	1,981
Accrued expenses and other current liabilities	9,234	11,376
Operating lease liabilities	(620)	(238)
Other non-current liabilities	314	472
Net cash used in operating activities	(185,467)	(128,050)
Cash flows from investing activities:
Purchases of property, plant and equipment	(5,662)	(2,270)
Purchase of short-term investments	(489,516)	(583,412)
Proceeds from sales and maturities of short-term investments	592,379	443,180
Net cash provided by (used in) investing activities	97,201	(142,502)
Cash flows from financing activities:
Proceeds from issuance of common stock, net of underwriting fees and discounts	0	149,854
Proceeds from issuance of prefunded warrants to purchase common stock, net of underwriting fees and discounts	0	92,778
Proceeds from issuance of common stock through ATM sales, net of offering costs	0	37,438
Proceeds from long-term debt, net of debt issuance costs	15,000	28,154
Principal payment of finance lease obligation	(476)	(365)
Proceeds from exercise of stock options	1,759	3,444
Net cash provided by financing activities	16,283	311,303
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(86)	(109)
Net (decrease) increase in cash, cash equivalents and restricted cash	(72,069)	40,642
Cash, cash equivalents and restricted cash at beginning of period	148,226	107,584
Cash, cash equivalents and restricted cash at end of period	76,157	148,226
Supplemental disclosure of cash flow information:
Cash paid during the period for interest	3,044	1,066
Cash paid for income taxes	300	0
Supplemental disclosure of non-cash investing and financing activities:
Purchases of property and equipment included in accounts payable	101	103
Lease assets obtained in exchange for new operating lease liabilities	$ 0	$ 290

Income taxes - Components of deferred tax assets and liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Deferred tax assets:
Net operating loss carryforwards	$ 141,911	$ 93,788
Property, plant and equipment	4,706	4,535
Capitalized start-up costs	1,199	1,301
Stock compensation	13,798	14,757
Accrued expenses	3,221	2,906
Lease liability	7,938	7,964
Other	39	24
Total deferred tax assets	172,812	125,275
Valuation allowance	(161,890)	(113,889)	$ (74,892)
Net deferred tax assets	10,922	11,386
Deferred tax liabilities:
Right of use asset	(10,922)	(11,386)
Total deferred tax liabilities	(10,922)	(11,386)
Net deferred tax assets (liabilities)	$ 0	$ 0

Net loss per share - Narrative (Details) - shares	1 Months Ended	12 Months Ended
Net loss per share - Narrative (Details) - shares	Dec. 31, 2022	Mar. 31, 2024	Mar. 31, 2023
Pre-funded warrants
Diluted net loss per share attributable to common stockholders
Common stock, authorized (in shares)	4,200,000	5,281,616	9,484,238

Income taxes - Valuation allowance for deferred tax assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Deferred Tax Assets, Valuation Allowance [Roll Forward]
Valuation allowance as of beginning of year	$ 113,889	$ 74,892
Increases recorded to income tax provision	45,941	41,063
Increases (decreases) recorded to equity	2,060	(2,066)
Valuation allowance as of end of year	$ 161,890	$ 113,889

Subsequent events	12 Months Ended
Subsequent events	Mar. 31, 2024
Subsequent Events [Abstract]
Subsequent events	17. Subsequent events In April 2024, the Company granted an equity award to a newly hired executive as a material inducement to enter into employment with the Company. The grant constitutes an "employment inducement grant" in accordance with Rule 5635(c)(4) of the Nasdaq Listing Rules and was issued outside of the 2018 Plan and each of the other stock incentive plans described above. The inducement grant included a nonqualified stock option to purchase up to 75,000 shares of the Company's common stock, as well as a restricted stock unit grant representing 50,000 shares of the Company's common stock. These stock option and restricted stock unit inducement grants have terms and conditions consistent with those set forth under the 2018 Plan and vest under the same respective vesting schedules as stock option and restricted stock unit awards granted under the 2018 Plan.

Long-term debt - Maturity of Debt (Details) - Line of Credit - Term Loan Facility - Secured Debt $ in Thousands	Mar. 31, 2024 USD ($)
Debt Instrument [Line Items]
2025	$ 0
2026	0
2027	20,145
Thereafter	27,769
Total	$ 47,914

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482900/835-30-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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Reference 8: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Publisher FASB
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 11: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Publisher FASB
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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Reference 20: http://www.xbrl.org/2003/role/disclosureRef
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Reference 21: http://www.xbrl.org/2003/role/disclosureRef
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Reference 22: http://www.xbrl.org/2003/role/disclosureRef
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Reference 23: http://www.xbrl.org/2003/role/disclosureRef
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Reference 24: http://www.xbrl.org/2003/role/disclosureRef
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Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

+ Details

Long-term debt - Summary of Debt (Details) - Secured Debt - Line of Credit - Term Loan Facility - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023
Debt Instrument [Line Items]
Principal loan balance	$ 45,749	$ 30,222
Facility charge and diligence fee	(266)	(315)
Unamortized issuance costs	(1,191)	(1,410)
Accumulated end of term fee	517	151
Long term debt, net	$ 44,809	$ 28,648

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

Significant agreements (Details) $ in Thousands	1 Months Ended			12 Months Ended
Significant agreements (Details) $ in Thousands	Jul. 31, 2023 patient	Dec. 31, 2022	Jan. 31, 2020 patient	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)
Significant agreements
Research and development				$ 174,963	$ 126,527
Prepaid expenses and other current assets				8,077	6,278
Bristol-Myers Squibb Company
Significant agreements
Number of patients \| patient			125
Regeneron Pharmaceuticals, Inc \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Significant agreements
Offset to research and development expenses					1,100
Proceeds from collaborators				0	3,100
Roche
Significant agreements
Collaboration arrangement, termination, period to provide written notice		60 days
Prepaid expenses and other current assets				1,800	900
Roche \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Significant agreements
Proceeds from collaborators				1,700	0
Research and development				$ 2,700	$ 900
Incyte Corporation
Significant agreements
Number of patients \| patient	40
Collaboration arrangement, termination, period after material breach	30 days
Collaboration arrangement, termination, period to agree on protocol and budget	90 days

Commitments and contingencies - Income Statement Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Lessee, Lease, Description [Line Items]
Finance Lease Costs	$ 2,428	$ 2,428
Operating Lease Costs	1,122	1,018
Total lease cost	5,713	5,643
Research and development
Lessee, Lease, Description [Line Items]
Finance Lease Costs	2,428	2,071
Operating Lease Costs	911	421
Total lease cost	5,713	5,643
Selling, general and administrative
Lessee, Lease, Description [Line Items]
Finance Lease Costs	0	358
Operating Lease Costs	211	596
Other income, net
Lessee, Lease, Description [Line Items]
Finance Lease Costs	$ 2,163	$ 2,197

Short-term investments

12 Months Ended

Mar. 31, 2024

Short-Term Investments [Abstract]

Short-term investments

As of March 31, 2024 and 2023, the Company's available-for-sale investments by type, consisted of the following:


	March 31, 2024
	Amortized cost		Gross unrealized gains		Gross unrealized losses		Credit Losses		Fair value
US Government agency bonds	$	199,905	$	33	$	(117)	$	—	$	199,821
US Treasury bonds	146,417		11		(38)		$	—	146,390
	$	346,322	$	44	$	(155)	$	—	$	346,211


	March 31, 2023
	Amortized cost		Gross unrealized gains		Gross unrealized losses		Credit Losses		Fair value
US Government agency bonds	$	240,371	$	187	$	(203)	$	—	$	240,355
US Treasury bonds	196,488		77		(124)		—		196,441
	$	436,859	$	264	$	(327)	$	—	$	436,796

As of March 31, 2024, available-for-sale securities consisted of investments that mature within one year. As of March 31, 2023, available-for-sale securities consisted of investments that mature within one year, with the exception of certain U.S. Government agency bonds and U.S. Treasury bonds which had maturities between one and two years and an aggregate fair value of $15.1 million.

Summary of significant accounting policies (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Accounting Policies [Abstract]
Cash equivalents	$ 41,100	$ 121,500
Summary of significant accounting policies
Restricted cash	1,700	1,636
Research and development incentives income	1,920	2,914
Research and development incentives receivable, current	4,922	2,939
Foreign currency transaction gains (losses)	(826)	5,483
Unrealized gains (losses) on short-term investments	$ (48)	1,219
Minimum percentage of benefit recognized is being realized upon ultimate settlement	50.00%
United Kingdom \| Maximum
Summary of significant accounting policies
Percentage of qualifying research and development expenses reimbursed by government	14.50%
Operating Lease
Summary of significant accounting policies
Restricted cash	$ 1,700	$ 1,700
Office equipment
Summary of significant accounting policies
Property, plant and equipment, useful life (in years)	5 years
Computer equipment and software
Summary of significant accounting policies
Property, plant and equipment, useful life (in years)	3 years
Plant, manufacturing and laboratory equipment
Summary of significant accounting policies
Property, plant and equipment, useful life (in years)	5 years
Capitalized software \| Minimum
Summary of significant accounting policies
Property, plant and equipment, useful life (in years)	3 years
Capitalized software \| Maximum
Summary of significant accounting policies
Property, plant and equipment, useful life (in years)	5 years
Leasehold improvements
Summary of significant accounting policies
Property, plant and equipment, useful life (in years)	10 years

Income taxes - Unrecognized tax benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Unrecognized tax benefits as of beginning of year	$ 8,757	$ 0
(Decreases) increases for tax positions taken during prior years	(90)
(Decreases) increases for tax positions taken during prior years		8,757
Unrecognized tax benefits as of end of year	$ 8,667	$ 8,757

Stock-based compensation - Additional information (Details) $ / shares in Units, $ in Millions				1 Months Ended		12 Months Ended
	Apr. 01, 2023 shares	Apr. 01, 2022 shares	Jul. 09, 2018 shares	Dec. 31, 2022 shares	Jul. 31, 2017	Mar. 31, 2024 USD ($) $ / shares shares	Mar. 31, 2023 USD ($) $ / shares shares	Apr. 01, 2021 shares
Stock-Based Compensation
Stockholders' equity, exchange ratio					1
Option to purchase (in shares)						2,394,124
Unrecognized compensation cost related to unvested common stock options \| $						$ 33.0
Expenses expected to be recognized over a weighted average remaining period						2 years 6 months
Weighted average grant-date fair value (in dollars per share) \| $ / shares						$ 11.41	$ 12.80
Intrinsic value of stock options exercised \| $						$ 1.4	$ 2.7
Unrecognized compensation cost \| $						$ 29.9
Pre-funded warrants
Stock-Based Compensation
Common stock, authorized (in shares)				4,200,000		5,281,616	9,484,238
Newly-Hired Executive
Stock-Based Compensation
Option to purchase (in shares)						125,000	82,500
2017 Plan
Stock-Based Compensation
Shares authorized (in shares)						2,659,885
Number of shares available for grant (in shares)			2,520,247
2018 Plan
Stock-Based Compensation
Shares authorized (in shares)			3,617,968
Number of shares available for grant (in shares)						2,284,141
Share based payment award percentage of outstanding shares			4.00%
Additional shares authorized (in shares)	2,646,422
ESPP
Stock-Based Compensation
Share based payment award percentage of outstanding shares			1.00%
Additional shares authorized (in shares)		661,605	697,224
Common stock reserved for issuance (in shares)			348,612					2,738,208
Stock options
Stock-Based Compensation
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
Stock options \| Minimum
Stock-Based Compensation
Expiration period for persons holding more than ten percent of voting power						10 years
Stock options \| Maximum
Stock-Based Compensation
Expiration period for persons holding ten percent of voting power						5 years
RSUs
Stock-Based Compensation
Share based payment award vesting period						4 years
Unrecognized compensation cost \| $						$ 27.0
RSUs \| Share-based Payment Arrangement, Tranche One
Stock-Based Compensation
Share based payment award vesting period						1 year
RSUs \| Newly-Hired Executive
Stock-Based Compensation
Grant (in shares)						83,330	55,000
PSUs
Stock-Based Compensation
Grant (in shares)						368,980
Unrecognized compensation cost \| $						$ 2.9

Stock-based compensation - Summary of RSU and PSU Activity (Details) - Restricted and Performance Stock Units	12 Months Ended
	Mar. 31, 2024 $ / shares shares
Number of Shares
Beginning balance (in shares) \| shares	1,351,280
Grant (in shares) \| shares	1,771,872
Vested (in shares) \| shares	(371,949)
Cancelled (in shares) \| shares	(353,313)
Ending balance (in shares) \| shares	2,397,890
Weighted Average Grant Date Fair Value
Beginning balance (in dollars per share) \| $ / shares	$ 24.38
Granted (in dollars per share) \| $ / shares	15.07
Vested (in dollars per share) \| $ / shares	25.26
Cancelled (in dollars per share) \| $ / shares	20.25
Ending balance (in dollars per share) \| $ / shares	$ 17.97

Stock-based compensation - Stock option activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Number of Shares
Outstanding at beginning of the period (in shares)	7,454,828
Option to purchase (in shares)	2,394,124
Exercised (in shares)	(164,221)
Cancelled (in shares)	(1,032,475)
Outstanding at end of the period (in shares)	8,652,256	7,454,828
Options exercisable (in shares)	5,483,718
Options vested and expected to vest (in shares)	8,652,256
Weighted Average Exercise Price
Outstanding at beginning of the period (in dollars per share)	$ 17.24
Granted (in dollars per share)	16.90
Exercised (in dollars per share)	10.71
Cancelled (in dollars per share)	20.05
Outstanding at end of the period (in dollars per share)	16.94	$ 17.24
Options exercisable (in dollars per share)	15.65
Options vested and expected to vest (in dollars per share)	$ 16.94
Weighted Average Contractual Term (Years)
Outstanding (years)	6 years 7 months 9 days	6 years 10 months 17 days
Options exercisable (years)	5 years 4 months 24 days
Options vested and expected to vest (in years)	6 years 7 months 9 days
Aggregate Intrinsic Value
Outstanding	$ 5,748	$ 31,244
Options exercisable	5,738
Options vested and expected to vest	$ 5,748

Short-term investments (Details) - USD ($) $ in Thousands	12 Months Ended
Short-term investments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023
Short-term investments
Amortized cost	$ 346,322	$ 436,859
Gross unrealized gains	44	264
Gross unrealized losses	(155)	(327)
Credit Losses	0	0
Fair value	346,211	436,796
US Government Agency bonds
Short-term investments
Amortized cost	199,905	240,371
Gross unrealized gains	33	187
Gross unrealized losses	(117)	(203)
Credit Losses	0	0
Fair value	199,821	240,355
US Treasury bonds
Short-term investments
Amortized cost	146,417	196,488
Gross unrealized gains	11	77
Gross unrealized losses	(38)	(124)
Credit Losses	0	0
Fair value	146,390	$ 196,441
Investments maturing between one and two years	$ 15,100

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480524/946-210-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480524/946-210-50-6

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480524/946-210-50-12

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
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-Name Accounting Standards Codification
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480524/946-210-50-6

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 946
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483580/946-220-50-3

+ Details

Short-term investments (Tables)

12 Months Ended

Mar. 31, 2024

Short-Term Investments [Abstract]

Schedule of short-term investments

As of March 31, 2024 and 2023, the Company's available-for-sale investments by type, consisted of the following:


	March 31, 2024
	Amortized cost		Gross unrealized gains		Gross unrealized losses		Credit Losses		Fair value
US Government agency bonds	$	199,905	$	33	$	(117)	$	—	$	199,821
US Treasury bonds	146,417		11		(38)		$	—	146,390
	$	346,322	$	44	$	(155)	$	—	$	346,211


	March 31, 2023
	Amortized cost		Gross unrealized gains		Gross unrealized losses		Credit Losses		Fair value
US Government agency bonds	$	240,371	$	187	$	(203)	$	—	$	240,355
US Treasury bonds	196,488		77		(124)		—		196,441
	$	436,859	$	264	$	(327)	$	—	$	436,796

Property, plant and equipment, net

12 Months Ended

Mar. 31, 2024

Property, Plant and Equipment [Abstract]

Property, plant and equipment, net

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


	March 31, 2024		March 31, 2023

Office equipment	$	1,464	$	1,240
Computer equipment	1,975		1,806
Plant and laboratory equipment	10,423		9,186
Leasehold improvements	1,886		1,706
Capitalized software	3,515		—
Construction in progress	1,117		783
	20,380		14,721
Less: Accumulated depreciation and amortization	(9,897)		(7,242)
	$	10,483	$	7,479

Depreciation and amortization expense was $2.7 million and $2.4 million for the years ended March 31, 2024 and 2023, respectively, and recorded within research and development and selling, general and administrative expenses in the consolidated statement of operations.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net loss	$ (215,794)	$ (174,284)
Other comprehensive loss:
Foreign currency translation (loss) gain	(826)	5,483
Net unrealized (loss) gain on short-term investments, net of tax of $0	(48)	1,219
Comprehensive loss	$ (216,668)	$ (167,582)

- Definition

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

+ References

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+ Details

Stock-based compensation - Assumptions to determine grant-date fair value of stock options (Details) - Stock options	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Stock-based Compensation
Risk-free interest rate	3.75%	2.83%
Expected term (in years)	6 years	6 years
Expected volatility	74.20%	75.20%
Expected dividend yield	0.00%	0.00%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details

Accrued expenses and other current liabilities

12 Months Ended

Mar. 31, 2024

Accrued expenses and other current liabilities

Accrued expenses and other current liabilities

Accrued expenses and other current liabilities consisted of the following:


	March 31, 2024		March 31, 2023
Accrued research and development costs	$	16,376	$	11,261
Accrued compensation and benefits costs	13,906		9,909
Accrued professional fees	369		540
Other	3,330		2,994
	$	33,981	$	24,704

Subsequent events (Details) - shares	1 Months Ended	12 Months Ended
Subsequent events (Details) - shares	Apr. 30, 2024	Mar. 31, 2024
Subsequent Event [Line Items]
Option to purchase (in shares)		2,394,124
Subsequent Event
Subsequent Event [Line Items]
Option to purchase (in shares)	75,000
Subsequent Event \| RSUs
Subsequent Event [Line Items]
Grant (in shares)	50,000

Net loss per share - Computation of diluted net loss per share attributable to common stockholders (Details) - shares	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
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 (in shares)	8,652,256	7,454,828
Unvested restricted and performance stock units
Diluted net loss per share attributable to common stockholders
Antidilutive securities excluded from computation of diluted weighted average shares outstanding (in shares)	2,397,890	1,351,280
Warrants to purchase common stock
Diluted net loss per share attributable to common stockholders
Antidilutive securities excluded from computation of diluted weighted average shares outstanding (in shares)	497,344	497,344

Long-term debt (Tables)

12 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Schedule of long-term debt

The summary of obligations under the term loan as of March 31, 2024 and 2023 consisted of the following (in thousands):


	March 31, 2024		March 31, 2023
Principal loan balance	$	45,749	$	30,222
Facility charge and diligence fee	(266)		(315)
Unamortized issuance costs	(1,191)		(1,410)
Accumulated end of term fee	517		151
Long term debt, net	$	44,809	$	28,648

Maturities of long-term debt

The annual principal payments by fiscal year due under the Loan Agreement as of March 31, 2024 were as follows:


	March 31, 2024
2025	—
2026	—
2027	20,145
Thereafter	27,769
Total	$	47,914

- 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://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69B

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69E
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69E

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482925/835-30-45-2

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482925/835-30-45-1A

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
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-URI https://asc.fasb.org//1943274/2147481112/505-10-50-3

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 835
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-Section 55
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-URI https://asc.fasb.org//1943274/2147482949/835-30-55-8

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI https://asc.fasb.org//1943274/2147481112/505-10-50-7

+ Details

Nature of the business	12 Months Ended
Nature of the business	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of the business	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 Group, Inc., whose predecessor was founded in 2015, is the parent company of its wholly owned, direct and indirect subsidiaries: Replimune Limited (“Replimune UK”); Replimune, Inc. (“Replimune US”); Replimune Securities Corporation; and Replimune (Ireland) Limited. 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. 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 $215.8 million and $174.3 million for the years ended March 31, 2024 and 2023, respectively. In addition, as of March 31, 2024, the Company had an accumulated deficit of $701.3 million. The Company expects to continue to generate operating losses for the foreseeable future. As of 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.

Income taxes (Tables)

12 Months Ended

Mar. 31, 2024

Income Tax Disclosure [Abstract]

Schedule of net loss before income taxes

Loss before income taxes for the years ended March 31, 2024 and 2023 were as follows:


	Year Ended March 31,
	2024		2023
United States	$	(19,367)	$	(18,367)
United Kingdom	(196,019)		(155,629)
Total	$	(215,386)	$	(173,996)

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

A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective tax rate for the years ended March 31, 2024 and 2023 is as follows:


	Year Ended March 31,
	2024		2023
U.S. federal statutory income tax rate	-21.0	%	-21.0	%
State taxes, net of federal benefit	-0.3	%	-0.6	%
Research and development	0.7	%	1	%
Stock compensation	3.0	%	-0.1	%
Foreign tax rate differential	-3.6	%	1.8	%
Change in tax rates	0.0	%	-6.0	%
Change in valuation allowance	21.4	%	23.6	%
Other	0.0	%	1.5	%
	0.2	%	0.2	%

Schedule of components of deferred tax assets and liabilities

Components of the Company’s deferred tax assets as of March 31, 2024 and 2023 were as follows:


	Year Ended March 31,
	2024		2023
Deferred tax assets:
Net operating loss carryforwards	$	141,911	$	93,788
Property, plant and equipment	4,706		4,535
Capitalized start-up costs	1,199		1,301
Stock compensation	13,798		14,757
Accrued expenses	3,221		2,906
Lease liability	7,938		7,964
Other	39		24
Total deferred tax assets	172,812		125,275
Valuation allowance	(161,890)		(113,889)
Net deferred tax assets	10,922		11,386

Deferred tax liabilities:
Right of use asset	(10,922)		(11,386)
Total deferred tax liabilities	(10,922)		(11,386)
Net deferred tax assets (liabilities)	$	—	$	—

Schedule of changes in the valuation allowance for deferred tax assets

Changes in the valuation allowance for deferred tax assets during the years ended March 31, 2024 and 2023 related primarily to the increase in net operating loss carryforwards were as follows:


	Year Ended March 31,
	2024		2023
Valuation allowance as of beginning of year	$	113,889	$	74,892
Increases recorded to income tax provision	45,941		41,063
Increases (decreases) recorded to equity	2,060		(2,066)
Valuation allowance as of end of year	$	161,890	$	113,889

Schedule of unrecognized tax benefits

Changes in the Company's gross unrecognized tax benefits from uncertain tax positions consisted of the following:


	Year Ended March 31,
	2024		2023
Unrecognized tax benefits as of beginning of year	$	8,757	$	—
(Decreases) increases for tax positions taken during prior years	(90)		8,757
Unrecognized tax benefits as of end of year	$	8,667	$	8,757

Property, plant and equipment, net (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Property, plant and equipment, net
Property, plant and equipment , gross	$ 20,380	$ 14,721
Less: Accumulated depreciation and amortization	(9,897)	(7,242)
Property, plant and equipment , net	10,483	7,479
Depreciation and amortization expense	2,655	2,447
Office equipment
Property, plant and equipment, net
Property, plant and equipment , gross	1,464	1,240
Computer equipment
Property, plant and equipment, net
Property, plant and equipment , gross	1,975	1,806
Plant and laboratory equipment
Property, plant and equipment, net
Property, plant and equipment , gross	10,423	9,186
Leasehold improvements
Property, plant and equipment, net
Property, plant and equipment , gross	1,886	1,706
Capitalized software
Property, plant and equipment, net
Property, plant and equipment , gross	3,515	0
Construction in progress
Property, plant and equipment, net
Property, plant and equipment , gross	$ 1,117	$ 783

Geographic information

12 Months Ended

Mar. 31, 2024

Segments, Geographical Areas [Abstract]

Geographic Information

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, 2024		March 31, 2023
United States	$	8,992	$	5,836
United Kingdom	1,491		1,643
	$	10,483	$	7,479

Commitments and contingencies

12 Months Ended

Mar. 31, 2024

Commitments and Contingencies Disclosure [Abstract]

Commitments and contingencies

Leases

The Company leases real estate assets and equipment, and determination if an arrangement is a lease occurs at inception. For leases with terms greater than 12 months, the Company records a related right-of-use (“ROU”) asset and lease liability at the present value of lease payments over the term. Many leases include fixed rental escalation clauses, renewal options and/or termination options that are factored into the determination of lease payments when appropriate. The Company’s leases do not provide an implicit rate, and thus the Company estimated the incremental borrowing rate in calculating the present value of the lease payments. The Company has elected not to record a ROU asset and lease obligation for short-term leases (with terms less than 12 months) or separate non-lease components from associated lease components for its real estate lease assets. As a result, all contract consideration is allocated to the single lease component.

The Company’s leases have remaining lease terms of five years to fifteen years. Some of the Company's leases include one or more options to renew with renewal terms that can extend the lease for additional years, or options to terminate the leases, both at the Company’s discretion. The Company’s lease terms include options to extend or terminate leases when the Company concludes it is reasonably certain that it would exercise those options. Lease expense for minimum lease payments is recognized 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.

The table below presents the lease-related costs which are included in the consolidated statements of operations for the years ended as of March 31, 2024 and 2023:


	Year ended March 31,
	2024		2023
Lease cost
Finance lease costs:
Amortization of right-to-use asset	$	2,428	$	2,428
Interest on lease liabilities	2,163		2,197
Operating lease costs	1,122		1,018
Total lease cost	$	5,713	$	5,643

The following table summarizes the classification of lease costs in the consolidated statement of operations for the years ended March 31, 2024 and 2023 as follows:


	Year ended March 31,
	2024		2023
Finance Lease Costs
Research and development	$	2,428	$	2,071
Selling, general and administrative	—		358
Other income, net	2,163		2,197
Operating Lease Costs
Research and development	911		421
Selling, general and administrative	211		596
Total lease cost	$	5,713	$	5,643


	March 31, 2024
	Operating leases		Financing lease		Total
2025	$	1,161	$	2,718	$	3,879
2026	1,170		2,799		3,969
2027	1,136		2,883		4,019
2028	1,085		2,969		4,054
2029	1,004		3,058		4,062
Thereafter	923		31,995		32,918
Total lease payments	6,479		46,422		52,901
Less: interest	1,547		20,294		21,841
Total lease liabilities	$	4,932	$	26,128	$	31,060

The following table provides lease disclosure as of and for the year ended March 31, 2024:


	March 31, 2024			March 31, 2023
Leases
Right-to-use operating lease asset	$	4,635		$	5,208
Right-to-use finance lease asset	37,237			39,665
Total lease assets	$	41,872		$	44,873
Operating lease liabilities, current	$	1,161		$	1,118
Finance lease liabilities, current	2,718			2,639
Operating lease liabilities, non-current	3,771			4,389
Finance lease liabilities, non-current	23,410			23,965
Total lease liabilities	$	31,060		$	32,111
Other information
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	1,059		$	1,014
Operating cash flows from finance leases	$	2,163		$	2,197
Financing cash flows from finance leases	$	476		$	365
Right-to-use asset obtained in exchange for new operating lease liabilities	$	—		$	290
Weighted-average remaining lease term – operating leases	5.6 years			6.6 years
Weighted-average remaining lease term – financing leases	15.3 years			16.3 years
Weighted-average discount rate – operating leases	10.3		%	10.3		%
Weighted-average discount rate – financing leases	8.3		%	8.3		%

The variable lease costs and short-term lease costs were insignificant for the years ended March 31, 2024 and 2023, respectively.

Manufacturing commitments

The Company has entered into an agreement with a contract manufacturing organization to provide clinical trial products. As of March 31, 2024 and 2023, the Company had committed to minimum payments under these arrangements totaling $0.9 million and $1.0 million.

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 executive management team and 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, 2024 or 2023.

Legal proceedings

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

Accrued expenses and other current liabilities (Tables)

12 Months Ended

Mar. 31, 2024

Accrued expenses and other current liabilities

Schedule of accrued expenses and other current liabilities

Accrued expenses and other current liabilities consisted of the following:


	March 31, 2024		March 31, 2023
Accrued research and development costs	$	16,376	$	11,261
Accrued compensation and benefits costs	13,906		9,909
Accrued professional fees	369		540
Other	3,330		2,994
	$	33,981	$	24,704

Fair value of financial assets and liabilities

12 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

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, 2024 Using:
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	—	$	41,077	$	—	$	41,077
Short-term investments:
US Government Agency bonds	—		199,821		—		199,821
US Treasury bonds	—		146,390		—		146,390
	$	—	$	387,288	$	—	$	387,288


	Fair Value Measurements as of March 31, 2023 Using:
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	—	$	121,455	$	—	$	121,455
Short-term investments:
US Government Agency bonds	—		240,355		—		240,355
US Treasury bonds	—		196,441		—		196,441
	$	—	$	558,251	$	—	$	558,251

The underlying securities held in the money market funds held by the Company are all government backed securities. During the years ended March 31, 2024 and 2023, there were no transfers between levels.

Valuation of cash equivalents and short-term investments

Money market funds, U.S. Treasury bonds and U.S. Government Agency bonds 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, 2024 and March 31, 2023.

- 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

Income taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Income taxes - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023
Operating Loss Carryforwards [Line Items]
Income tax provision	$ 408	$ 288
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	32,000
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	528,700
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 60,100

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Fair value of financial assets and liabilities (Details) - Recurring - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023
Fair value of financial assets and liabilities
Assets fair value	$ 387,288	$ 558,251
Money market funds
Fair value of financial assets and liabilities
Assets fair value	41,077	121,455
US Government Agency bonds
Fair value of financial assets and liabilities
Assets fair value	199,821	240,355
US Treasury bonds
Fair value of financial assets and liabilities
Assets fair value	146,390	196,441
Level 1
Fair value of financial assets and liabilities
Assets fair value	0	0
Level 1 \| Money market funds
Fair value of financial assets and liabilities
Assets fair value	0	0
Level 1 \| US Government Agency bonds
Fair value of financial assets and liabilities
Assets fair value	0	0
Level 1 \| US Treasury bonds
Fair value of financial assets and liabilities
Assets fair value	0	0
Level 2
Fair value of financial assets and liabilities
Assets fair value	387,288	558,251
Level 2 \| Money market funds
Fair value of financial assets and liabilities
Assets fair value	41,077	121,455
Level 2 \| US Government Agency bonds
Fair value of financial assets and liabilities
Assets fair value	199,821	240,355
Level 2 \| US Treasury bonds
Fair value of financial assets and liabilities
Assets fair value	146,390	196,441
Level 3
Fair value of financial assets and liabilities
Assets fair value	0	0
Level 3 \| Money market funds
Fair value of financial assets and liabilities
Assets fair value	0	0
Level 3 \| US Government Agency bonds
Fair value of financial assets and liabilities
Assets fair value	0	0
Level 3 \| US Treasury bonds
Fair value of financial assets and liabilities
Assets fair value	$ 0	$ 0

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 31, 2024	Mar. 31, 2023
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	150,000,000	150,000,000
Common stock, issued (in shares)	61,415,105	56,676,313
Common stock, outstanding (in shares)	61,415,105	56,676,313

Benefit plans (Details) - USD ($) $ in Millions	12 Months Ended
Benefit plans (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
401(k) Plan
Defined Contribution Plan Disclosure [Line Items]
Contributions to the plan	$ 2.1	$ 1.3
Pension Plan
Defined Contribution Plan Disclosure [Line Items]
Maximum percentage of contribution by employee of their annual base salary (as a percent)	8.00%

Net loss per share - Computation of Net Loss per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Numerator:
Net loss	$ (215,794)	$ (174,284)
Denominator:
Weighted average common shares outstanding, basic (in shares)	66,569,894	58,213,010
Weighted average common shares outstanding, diluted (in shares)	66,569,894	58,213,010
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (3.24)	$ (2.99)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (3.24)	$ (2.99)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482635/260-10-55-15

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (e)(4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (f)
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-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-11

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-11

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Subparagraph (a)
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-URI https://asc.fasb.org//1943274/2147483443/250-10-50-7

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482689/260-10-45-2

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 60B
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482689/260-10-45-60B

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
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+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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- Definition

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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+ Details

Income taxes

12 Months Ended

Mar. 31, 2024

Income Tax Disclosure [Abstract]

Income taxes

Loss before income taxes for the years ended March 31, 2024 and 2023 were as follows:


	Year Ended March 31,
	2024		2023
United States	$	(19,367)	$	(18,367)
United Kingdom	(196,019)		(155,629)
Total	$	(215,386)	$	(173,996)

During the year ended March 31, 2024 and 2023, the Company recorded an income tax provision of $0.4 million and $0.3 million, respectively, related to U.S. current taxes primarily due to the transfer pricing arrangement between the U.S. and the U.K., as well as unfavorable adjustments related to stock compensation, resulting in U.S. taxable income reduced by certain prior year available net operating losses.

Future realization of the tax benefits of existing temporary differences and net operating loss carryforwards ultimately depends on the existence of sufficient taxable income within the carryforward period. As of March 31, 2024 and 2023, the Company performed an evaluation to determine whether a valuation allowance was needed. The Company considered all available evidence, both positive and negative, which included the results of operations for the current and preceding years. It was determined that it was not possible to reasonably quantify future taxable income and determined that it is more likely than not that all of the deferred tax assets will not be realized. Accordingly, a full valuation allowance was maintained as of March 31, 2024 and 2023.

A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective tax rate for the years ended March 31, 2024 and 2023 is as follows:


	Year Ended March 31,
	2024		2023
U.S. federal statutory income tax rate	-21.0	%	-21.0	%
State taxes, net of federal benefit	-0.3	%	-0.6	%
Research and development	0.7	%	1	%
Stock compensation	3.0	%	-0.1	%
Foreign tax rate differential	-3.6	%	1.8	%
Change in tax rates	0.0	%	-6.0	%
Change in valuation allowance	21.4	%	23.6	%
Other	0.0	%	1.5	%
	0.2	%	0.2	%

Components of the Company’s deferred tax assets as of March 31, 2024 and 2023 were as follows:


	Year Ended March 31,
	2024		2023
Deferred tax assets:
Net operating loss carryforwards	$	141,911	$	93,788
Property, plant and equipment	4,706		4,535
Capitalized start-up costs	1,199		1,301
Stock compensation	13,798		14,757
Accrued expenses	3,221		2,906
Lease liability	7,938		7,964
Other	39		24
Total deferred tax assets	172,812		125,275
Valuation allowance	(161,890)		(113,889)
Net deferred tax assets	10,922		11,386

Deferred tax liabilities:
Right of use asset	(10,922)		(11,386)
Total deferred tax liabilities	(10,922)		(11,386)
Net deferred tax assets (liabilities)	$	—	$	—

As of March 31, 2024, the Company had U.S. federal operating loss carryforwards of approximately $32.0 million, which can be carried forward indefinitely subject to 80% limitation of taxable income when utilized. As of March 31, 2024, the Company had U.S. state operating loss carryforwards of $60.1 million, which will begin to expire in 2039. As of March 31, 2024, the Company had U.K. operating loss carryforwards of approximately $528.7 million, which can be carried forward indefinitely. Such U.S. federal and state, as well as U.K., net operating loss carryforwards are based on tax returns filed and does not reflect uncertain tax positions in the U.S. and offsetting positions in the U.K. related to the transfer pricing arrangement.

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.

Changes in the valuation allowance for deferred tax assets during the years ended March 31, 2024 and 2023 related primarily to the increase in net operating loss carryforwards were as follows:


	Year Ended March 31,
	2024		2023
Valuation allowance as of beginning of year	$	113,889	$	74,892
Increases recorded to income tax provision	45,941		41,063
Increases (decreases) recorded to equity	2,060		(2,066)
Valuation allowance as of end of year	$	161,890	$	113,889

Changes in the Company's gross unrecognized tax benefits from uncertain tax positions consisted of the following:


	Year Ended March 31,
	2024		2023
Unrecognized tax benefits as of beginning of year	$	8,757	$	—
(Decreases) increases for tax positions taken during prior years	(90)		8,757
Unrecognized tax benefits as of end of year	$	8,667	$	8,757

The Company's unrecognized tax benefits primarily relate to the Company's transfer pricing arrangements.

The Company's unrecognized tax benefits, if recognized, would not impact the effective tax rate and income tax provision due to the Company's valuation allowance.

As of March 31, 2024 and 2023, the Company had not accrued interest or penalties related to uncertain income tax positions.

The Company files income tax returns in the U.S., Massachusetts and the U.K. In the normal course of business, the Company is subject to examination by U.S. federal and state as well as U.K. jurisdictions, where applicable. There are currently no pending income tax examinations. The Company is open to future U.S. federal income tax examination from 2020 to the present and in the U.K. from 2022 to the present. Although, carryforward attributes may still be adjusted upon examination if they either have been or will be used in a future period.

As of March 31, 2024 and 2023, income taxes on outside basis differences, primarily related to undistributed earnings, of the Company’s subsidiary have not been provided for as the Company intends to indefinitely reinvest its outside basis differences, and the undistributed earnings were in a cumulative and overall deficit.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

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+ Details

Significant agreements	12 Months Ended
Significant agreements	Mar. 31, 2024
Significant agreements
Significant agreements	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, nivolumab, its anti-PD-1 therapy, for use in the Company’s ongoing clinical trial of RP1. 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 use nivolumab in the clinical trial and agreed to supply nivolumab, at no cost to the Company, for use in the clinical trial. Both parties will own the study data produced in the clinical trial, other than study data related solely to nivolumab, which will belong solely to BMS, or study data related solely to RP1, which will belong solely to us. In January 2020, this agreement was expanded to cover an additional cohort of 125 patients with anti-PD-1 failed 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 (x) in the event of an uncured material breach by the other party, (y) in the event the other party is insolvent or in bankruptcy proceedings or (z) for safety reasons. Upon termination, the licenses granted to the Company to use BMS’s nivolumab in the clinical trial will terminate. 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 a Master Clinical Trial Collaboration and Supply Agreement with Regeneron. Pursuant to the agreement the Company agreed to undertake one or more clinical trials with Regeneron for the administration of the Company's product candidates in combination with cemiplimab, an anti-PD-1 therapy developed by Regeneron, across multiple solid tumor types. The first of which, agreed in June 2018, is the Company's ongoing clinical trial testing RP1 in combination with cemiplimab versus cemiplimab alone in patients with CSCC. Each clinical trial will be conducted pursuant to an agreed study plan which, among other things, will identify the name of the sponsor and which party will manage the particular study, and include the protocol, the budget and a schedule of clinical obligations. Pursuant to the terms of the agreement, each party granted the other party a non-exclusive license of their respective intellectual property and agreed to contribute the necessary resources needed to fulfill their respective obligations, in each case, under the terms of agreed study plans. The Company does not expect any further reimbursements from Regeneron related to the initial study plan of June 2018 and the CERPASS trial. The agreement contains representations, warranties, undertakings and indemnities customary for a transaction of this nature. The agreement also contains certain time-based covenants that restrict the Company from entering into a third-party arrangement with respect to the use of its product candidates in combination with an anti-PD-1 therapy and that restrict Regeneron from entering into a third-party arrangement with respect to the use of cemiplimab in combination with an HSV-1 virus, in each case, for the treatment of a tumor type that is the subject of a clinical trial to which the covenants apply. Unless otherwise mutually agreed in a future study plan, these covenants are only applicable to the Company's ongoing Phase 2 clinical trial in CSCC. 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 and 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 (ii) in the event of a material breach The agreement with Regeneron is accounted for under ASC 808, Collaborative Arrangements (“ASC 808”), as both parties are active participants and each party pays its own compound costs and share equally in development costs. The Company accounts 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 recognizes any amounts received from Regeneron in connection with this agreement as an offset to research and development expense within the consolidated statement of operations. In July 2022, Regeneron informed the Company that the costs of the study have reached the initial budget for the initial study plan of June 2018 and that Regeneron's reimbursement of CERPASS study costs to the Company have completed in the period ending June 30, 2022 in relation to the initial study budget. As a result of this notice from, and the ongoing communications with, Regeneron, the Company has not recorded any cost-sharing reimbursements from Regeneron in prepaid expenses and other current assets in the consolidated balance sheet or as an offset to research and development expense within the consolidated statement of operations since Regeneron informed it that Regeneron’s reimbursement of CERPASS study costs have completed. The Company does not expect any further reimbursements from Regeneron related to the initial study plan of June 2018. The Company did not record any costs as an offset to research and development expenses during the year ended March 31, 2024 and recorded $1.1 million during the year ended March 31, 2023. During the years ended March 31, 2024 and 2023, the Company did not make any payments to Regeneron under the terms of the agreement. During the years ended March 31, 2024 and 2023, the Company received payments under the terms of the agreement from Regeneron of $0.0 million and $3.1 million, respectively. There were no outstanding receivables from Regeneron associated with this agreement at March 31, 2024 or 2023. Roche In December 2022, the Company entered into a Master Clinical Trial Collaboration and Supply Agreement with Roche in relation to the Company's RP2 and RP3 programs in colorectal cancer, or CRC, and hepatocellular carcinoma, or HCC. Under the agreement, the companies intended to collaborate in 30 patient cohort signal finding studies in third-line, or 3L, CRC and in first- and second-line, or 1L and 2L, respectively, HCC. Following the Company's re-prioritization of its product development portfolio in December 2023, the Company has agreed with Roche to terminate the CRC collaboration and pursue the 2L cohort in HCC with RP2 only. Roche has expressed its intent to continue to supply its currently approved drugs, atezolizumab and bevacizumab for the 2L cohort in HCC but is unlikely to share costs following the Company's re-prioritization. The Company is in discussions with Roche about revising these agreements following the Company's changes to its RP2 and RP3 development plans. Under the terms of the initial agreement the Company retained the responsibility of operating the clinical trials as well as retaining all the rights to the development and commercialization of its product candidates. The agreement may be terminated by either party upon sixty days prior written notice to the other party. The agreement with Roche is accounted for under ASC 808, Collaborative Arrangements (“ASC 808”), as both parties are active participants and each party pays its own compound costs and shares equally in development costs in accordance with and up to the amount in the agreed upon first study plan. The Company accounts 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 recognizes any amounts received from Roche in connection with this agreement as an offset to research and development expense within the consolidated statement of operations. During the years ended March 31, 2024 and 2023, the Company did not make any payments to Roche under the terms of the agreement. The Company recorded $2.7 million and $0.9 million as an offset to research and development expenses during the years ended March 31, 2024 and 2023, respectively. During the years ended March 31, 2024 and 2023, the Company received payments under the terms of the agreement from Roche of $1.7 million and $0.0 million, respectively. As of March 31, 2024 and 2023, the Company recorded $1.8 million and $0.9 million as receivables from Roche in connection with this agreement, respectively. Incyte In July 2023, the Company entered into a Clinical Trial Collaboration and Supply Agreement with Incyte Corporation, or Incyte. Under the agreement, the companies will collaborate in a signal finding study in which Incyte will initiate and sponsor a clinical trial of INCB99280 (oral PD-L1 inhibitor) and RP1 in approximately 40 patients with unresectable, high risk CSCC in the neoadjuvant setting. Under the terms of the agreement, the Company will supply Incyte with RP1 for the study and share costs of the study equally with Incyte. The agreement may be terminated by either party upon (i) a material breach not reasonably cured within thirty days; (ii) the discontinuation of development of its clinical drug candidate; (iii) the unethical or illegal business practices of the other party; or (iv) if the parties have not agreed on the protocol or budget within ninety days of the effective date of the agreement. In addition, the Company may terminate the agreement upon the inappropriate or unsafe use of the RP1 product candidate. As of March 31, 2024, the Company and Incyte had not yet agreed on the protocol or budget. However, the Company and Incyte continue to discuss a potential protocol and neither party has triggered termination of the agreement in accordance with the termination right described in clause (iv) above. The parties are evaluating potential collaboration efforts pending further CERPASS data readout of RP1 in combination with cemiplimab and additional data for Incyte's product candidate INCB99280. During the year ended March 31, 2024, the Company did not make any payments to, or receive any payments from, Inctye under the terms of the agreement. Additionally, no costs were recorded to research and development expenses during the year ended March 31, 2024 related to this agreement. Amgen In August 2023 the Company entered into a Settlement Agreement with Amgen and mutually agreed to terminate the Company's challenges to Amgen's patents. In connection with the Settlement Agreement, the Company entered into a License and Covenant Agreement with Amgen in which the Company agreed to pay Amgen low single-digit royalty payments on net sales of its products that, but for the license, could be found to infringe a valid Amgen patent on a country-by-country and product-by-product basis.

Nature of the business (Details) - USD ($) $ in Thousands	12 Months Ended
Nature of the business (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Net loss	$ (215,794)	$ (174,284)
Accumulated deficit	$ (701,282)	$ (485,488)

- Definition

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

+ References

+ Details

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Stock-based compensation (Tables)

12 Months Ended

Mar. 31, 2024

Share-Based Payment Arrangement [Abstract]

Schedule of stock-based compensation expense

The following table summarizes the classification of stock-based compensation expense in the consolidated statements of operations for the years ended March 31, 2024 and 2023 as follows:


	Year ended March 31,
	2024		2023
Research and development	$	14,745	$	10,074
Selling, general and administrative	19,380		18,057
	$	34,125	$	28,131

The following table summarizes stock-based compensation expense by award type for the years ended March 31, 2024 and 2023 as follows:


	Year ended March 31,
	2024		2023
Stock options	$	21,594	$	19,521
Restricted and performance stock units	12,531		8,610
	$	34,125	$	28,131

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

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,
	2024		2023
Risk-free interest rate	3.75	%	2.83	%
Expected term (in years)	6.0		6.0
Expected volatility	74.2	%	75.2	%
Expected dividend yield	0	%	0	%

Summary of stock option activity

A summary of stock option activity under the Company’s equity incentive plans for the year ended March 31, 2024 is as follows:


	Number of Shares	Weighted Average Exercise Price		Weighted Average Contractual Term (Years)	Aggregate Intrinsic Value
Outstanding as of March 31, 2023	7,454,828	$	17.24	6.88	$	31,244
Granted	2,394,124	16.90
Exercised	(164,221)	10.71
Cancelled	(1,032,475)	20.05
Outstanding as of March 31, 2024	8,652,256	16.94		6.61	$	5,748
Options exercisable as of March 31, 2024	5,483,718	$	15.65	5.40	$	5,738
Options vested and expected to vest as of March 31, 2024	8,652,256	$	16.94	6.61	$	5,748

Summary of changes in company's RSU

A summary of the changes in the Company’s RSUs and PSUs during the year ended March 31, 2024 is as follows:


	Number of Shares	Weighted Average Grant Date Fair Value
Outstanding as of March 31, 2023	1,351,280	$	24.38
Granted	1,771,872	15.07
Vested	(371,949)	25.26
Cancelled	(353,313)	20.25
Outstanding as of March 31, 2024	2,397,890	$	17.97

Summary of significant accounting policies

12 Months Ended

Mar. 31, 2024

Accounting Policies [Abstract]

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

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 as of March 31, 2024 and 2023, respectively. As of March 31, 2024 and 2023, the amount of cash equivalents included in cash and cash equivalents totaled $41.1 million and $121.5 million, respectively.

Restricted cash

The Company holds restricted cash in segregated bank accounts in connection with a letter of credit. As of March 31, 2024 and 2023, restricted cash consisted of $1.7 million, held for the benefit of the landlords in connection with our leases and for the Company's credit card program in the United Kingdom. These amounts have been classified as non-current assets on the Company’s consolidated balance sheets.

Short-term investments

No credit-related losses or impairments have been recognized on the Company's investments in available-for-sale debt securities during the years ended March 31, 2024 or 2023.

Property, plant and equipment


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

Impairment of long-lived assets

Fair value measurements

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

debt approximates its fair value at each balance sheet date due to its variable interest rate, which approximates a market interest rate.

Debt issuance costs

Segment information

Research and development costs

Research contract costs and accruals

Patent costs

Stock-based compensation

Research and development incentives and receivable

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 $1.9 million and $2.9 million during the years ended March 31, 2024 and 2023, respectively, in the consolidated statements of operations and a research and development incentives receivable of $4.9 million and $2.9 million as of March 31, 2024 and 2023, respectively, on the consolidated balance sheets.

Comprehensive loss

Comprehensive loss includes net loss as well as other changes in stockholders’ equity that result from transactions and economic events other than those with stockholders. For the year ended March 31, 2024, comprehensive loss included $0.8 million of foreign currency translation losses. For the year ended March 31, 2023, comprehensive loss included $5.5 million of foreign currency translation gains and $1.2 million of unrealized gains on short-term investments, net of tax.

Income taxes

Net income (loss) per share

Recently Issued Accounting Pronouncements

Summary of significant accounting policies (Tables)

12 Months Ended

Mar. 31, 2024

Accounting Policies [Abstract]

Schedule of property, plant and equipment, net

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 and software			3 years
Plant, manufacturing and laboratory equipment			5 years
Capitalized software			3 to 5 years
Leasehold improvements			Lesser of lease term or 10 years

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


	March 31, 2024		March 31, 2023

Office equipment	$	1,464	$	1,240
Computer equipment	1,975		1,806
Plant and laboratory equipment	10,423		9,186
Leasehold improvements	1,886		1,706
Capitalized software	3,515		—
Construction in progress	1,117		783
	20,380		14,721
Less: Accumulated depreciation and amortization	(9,897)		(7,242)
	$	10,483	$	7,479

Stock-based compensation

12 Months Ended

Mar. 31, 2024

Share-Based Payment Arrangement [Abstract]

Stock-based compensation

Stock-based compensation expense

The following table summarizes the classification of stock-based compensation expense in the consolidated statements of operations for the years ended March 31, 2024 and 2023 as follows:


	Year ended March 31,
	2024		2023
Research and development	$	14,745	$	10,074
Selling, general and administrative	19,380		18,057
	$	34,125	$	28,131

The following table summarizes stock-based compensation expense by award type for the years ended March 31, 2024 and 2023 as follows:


	Year ended March 31,
	2024		2023
Stock options	$	21,594	$	19,521
Restricted and performance stock units	12,531		8,610
	$	34,125	$	28,131

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 reorganization by Replimune Limited, pursuant to which each shareholder thereof exchanged their outstanding shares in Replimune Limited for shares in Replimune Group, Inc., on a one-for-one basis (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 have been or will be made under the 2015 Plan and any outstanding awards under the 2015 Plan have continued, and 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 were granted under the 2017 Plan only to the Company’s employees, including officers and directors who were also employees. Restricted stock awards and non-statutory stock options were granted under the 2017 Plan 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 none remained available for future grants as of March 31, 2024. 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 2018 Plan referenced below. 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. The number of shares reserved for issuance under the 2018 Plan will increase automatically on the first day of each April equal to 4.0% of the total number of shares of Company stock outstanding on the last trading day in the immediately preceding fiscal year, which includes for these purposes, the 5,281,616 shares issuable upon exercise of those pre-funded warrants described in Note 9 to these consolidated financial statements, or such lesser amount as determined by the Board. On April 1, 2023, the number of shares reserved for issuance under the 2018 Plan automatically increased by 2,646,422 shares pursuant to the terms of the 2018 Plan and based on total number of shares of Company stock

outstanding on March 31, 2023. As of March 31, 2024, 2,284,141 shares remained available for future grants under the 2018 Plan.

The 2015 Plan, the 2017 Plan and the 2018 Plan are 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. In 2021 the board of directors initiated the award of RSUs, under the 2018 Plan in addition to stock option awards available as part of the Company’s equity incentive for employees, officers, advisors and consultants of the Company. The RSUs typically vest over four approximately equal annual installments with the first such installment occurring on a designated vesting date that is approximately on the one year anniversary date of the date of grant and the subsequent installments occurring on the subsequent three annual anniversaries of the designated vesting date. In 2024 the Board of Directors approved the award of PSUs, under the 2018 Plan in addition to the aforementioned stock option awards and RSUs available as part of the Company’s equity incentive for employees, officers, advisors and consultants of the Company. The PSUs will vest in connection with the timely achievement of a specified corporate milestone, and the expense recognized for these awards is based on the grant date fair value of the Company's common stock multiplied by the number of units granted. The timing of recognition of this stock-based compensation expense is subject to our judgment as to when the performance conditions are considered probable of being achieved. The Company granted 368,980 PSUs under the 2018 Plan during the year ended March 31, 2024.

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, which includes for these purposes, the 5,281,616 shares issuable upon exercise of those pre-funded warrants described in Note 9 to these consolidated financial statements, 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 with the terms of the ESPP, on April 1, 2023, the number of shares reserved for issuance under the ESPP automatically increased by 661,605, for a total of 2,738,208 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. The Company’s ESPP is not currently active.

Out-of-Plan Inducement Grant

From time to time, the Company grants equity awards to newly hired executives as a material inducement to enter into employment with the Company. The grants constitute "employment inducement grants" in accordance with Rule 5635(c)(4) of the Nasdaq Listing Rules and was issued outside of the 2018 Plan and each of the other stock incentive plans described above. The inducement grants typically include nonqualified stock options to purchase shares of the Company's common stock, as well as restricted stock unit grants representing shares of the Company's common stock. These stock option and restricted stock unit inducement grants have terms and conditions consistent with those set forth under the 2018 Plan and vest under the same respective vesting schedules as stock option and restricted stock unit awards granted under the 2018 Plan. The inducement grants are included in the stock option and RSU award tables below. During the years ended March 31, 2024 and 2023, the Company granted 125,000 and 82,500 nonqualified stock options to purchase shares of the Company's common stock, respectively, and 83,330 and 55,000 restricted stock units, respectively, under employment inducement grants.

Stock option valuation

The fair value of stock option grants is estimated using the Black-Scholes option-pricing model. As the Company has limited company-specific historical and implied volatility information, the expected stock volatility is based on a combination of Replimune volatility and 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,
	2024		2023
Risk-free interest rate	3.75	%	2.83	%
Expected term (in years)	6.0		6.0
Expected volatility	74.2	%	75.2	%
Expected dividend yield	0	%	0	%

Stock options

A summary of stock option activity under the Company’s equity incentive plans for the year ended March 31, 2024 is as follows:


	Number of Shares	Weighted Average Exercise Price		Weighted Average Contractual Term (Years)	Aggregate Intrinsic Value
Outstanding as of March 31, 2023	7,454,828	$	17.24	6.88	$	31,244
Granted	2,394,124	16.90
Exercised	(164,221)	10.71
Cancelled	(1,032,475)	20.05
Outstanding as of March 31, 2024	8,652,256	16.94		6.61	$	5,748
Options exercisable as of March 31, 2024	5,483,718	$	15.65	5.40	$	5,738
Options vested and expected to vest as of March 31, 2024	8,652,256	$	16.94	6.61	$	5,748

As of March 31, 2024, there was $33.0 million of unrecognized compensation cost related to unvested common stock options, which is expected to be recognized over a weighted average period of 2.5 years.

The weighted average grant-date fair value of stock options granted during the years ended March 31, 2024 and 2023 was $11.41 and $12.80, respectively. The aggregate intrinsic value of stock options exercised during the years ended March 31, 2024 and 2023 was $1.4 million and $2.7 million, respectively.

Restricted and performance stock units

In January 2024, the Board approved a one-time PSU award under the 2018 Plan for all employees at the VP level and below as of January 31, 2024, subject to non-market performance and service conditions. The grants will become vested upon the achievement of the approval of the Company’s first Biologics License Application (“BLA”) for RP1 by the Food and Drug Administration (“FDA”) no later than June 30, 2026. The grant date fair value for the PSUs is determined based on the market price of the Company's common stock on the grant date and is recognized over the requisite service period if and when the achievement of such performance condition is determined to be probable by the Company. The Company reassesses the

probability of achieving the performance condition at each reporting period. As of March 31, 2024, the Company has not recognized any expense related to PSUs.

A summary of the changes in the Company’s RSUs and PSUs during the year ended March 31, 2024 is as follows:


	Number of Shares	Weighted Average Grant Date Fair Value
Outstanding as of March 31, 2023	1,351,280	$	24.38
Granted	1,771,872	15.07
Vested	(371,949)	25.26
Cancelled	(353,313)	20.25
Outstanding as of March 31, 2024	2,397,890	$	17.97

At March 31, 2024, there was $29.9 million of total unrecognized compensation cost related to unvested awards, which will be recognized over a weighted-average period of 2.5 years. Of the $29.9 million of total unrecognized compensation cost, performance based awards tied to the achievement of a company milestone account for approximately $2.9 million. The performance based awards will vest upon achievement of the performance milestone. The remaining $27.0 million in unrecognized compensation cost is related to restricted stock units which vest over time.

Audit Information	12 Months Ended
Audit Information	Mar. 31, 2024
Auditor Information [Abstract]
Auditor Firm ID	238
Auditor Name	PricewaterhouseCoopers LLP
Auditor Location	Boston, Massachusetts

Net loss per share

12 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

Net loss per share

The following table sets forth the computation of the Company’s basic and diluted net loss per share attributable to common stockholders (in thousands, except per share amounts):


	Year ended March 31,
	2024		2023
Numerator:
Net loss	$	(215,794)	$	(174,284)
Denominator:
Weighted average common shares outstanding, basic and diluted	66,569,894		58,213,010
Net loss per share, basic and diluted	$	(3.24)	$	(2.99)

The 5,281,616 shares of the Company's common stock issuable upon exercise of Pre-Funded Warrants described in Note 9 to these consolidated financial statements are included as outstanding common stock in the calculation of basic and diluted net loss per share.

The Company’s potentially dilutive securities, which include stock options, unvested restricted and performance stock units and warrants to purchase common 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 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 for the periods indicated because including them would have had an anti-dilutive effect:


	Year ended March 31,
	2024	2023
Options to purchase common stock	8,652,256	7,454,828
Unvested restricted and performance stock units	2,397,890	1,351,280
Warrants to purchase common stock	497,344	497,344

Commitments and contingencies - Future lease payments under operating and financing lease liabilities (Details) $ in Thousands	Mar. 31, 2024 USD ($)
Operating leases
2025	$ 1,161
2026	1,170
2027	1,136
2028	1,085
2029	1,004
Thereafter	923
Total lease payments	6,479
Less: interest	1,547
Total lease liabilities	4,932
Financing lease
2025	2,718
2026	2,799
2027	2,883
2028	2,969
2029	3,058
Thereafter	31,995
Total lease payments	46,422
Less: interest	20,294
Total lease liabilities	26,128
Total
2025	3,879
2026	3,969
2027	4,019
2028	4,054
2029	4,062
Thereafter	32,918
Total lease payments	52,901
Less: interest	21,841
Total lease liabilities	$ 31,060

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating expenses:
Research and development	$ 174,963	$ 126,527
Selling, general and administrative	59,810	50,553
Total operating expenses	234,773	177,080
Loss from operations	(234,773)	(177,080)
Other income (expense):
Research and development incentives	1,920	2,914
Investment income	23,356	10,006
Interest expense on finance lease liability	(2,163)	(2,197)
Interest expense on debt obligations	(4,497)	(1,963)
Other income (expense)	771	(5,676)
Total other income, net	19,387	3,084
Loss before income taxes	(215,386)	(173,996)
Income tax provision	408	288
Net loss	$ (215,794)	$ (174,284)
Earnings Per Share, Basic	$ (3.24)	$ (2.99)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (3.24)	$ (2.99)
Weighted average common shares outstanding, basic (in shares)	66,569,894	58,213,010
Weighted average common shares outstanding, diluted (in shares)	66,569,894	58,213,010

Cover Page - USD ($) $ in Millions	12 Months Ended
Cover Page - USD ($) $ in Millions	Mar. 31, 2024	May 13, 2024	Sep. 30, 2023
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Mar. 31, 2024
Current Fiscal Year End Date	--03-31
Document Transition Report	false
Entity File Number	001-38596
Entity Registrant Name	REPLIMUNE GROUP, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-2082553
Entity Address, Address Line One	500 Unicorn Park Drive
Entity Address, Address Line Two	Suite 303
Entity Address, City or Town	Woburn
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01801
City Area Code	781
Local Phone Number	222-9600
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	REPL
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 605.6
Entity Common Stock, Shares Outstanding		61,415,105
Documents Incorporated by Reference	The registrant intends to file a definitive proxy statement pursuant to Regulation 14A within 120 days of the end of the fiscal year ended March 31, 2024. Portions of such definitive proxy statement are incorporated by reference into Part III of this Annual Report on Form 10-K.
Entity Central Index Key	0001737953
Amendment Flag	false
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	FY

Stock-based compensation - Classification of expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Stock-Based Compensation
Stock-based compensation expense	$ 34,125	$ 28,131
Stock options
Stock-Based Compensation
Stock-based compensation expense	21,594	19,521
RSUs
Stock-Based Compensation
Stock-based compensation expense	12,531	8,610
Research and development
Stock-Based Compensation
Stock-based compensation expense	14,745	10,074
Selling, general and administrative
Stock-Based Compensation
Stock-based compensation expense	$ 19,380	$ 18,057

Long-term debt - Narrative (Details)			12 Months Ended
Long-term debt - Narrative (Details)	Jun. 28, 2023 USD ($)	Oct. 06, 2022 USD ($) advance	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 22, 2023 USD ($)
Debt Instrument [Line Items]
Interest expense on debt obligations			$ 4,497,000	$ 1,963,000
Secured Debt \| Line of Credit \| Term Loan Facility
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 200,000,000
Additional rate (as a percent)		1.75%
Stated interest rate (as a percent)		1.50%
Prepayment fee, first 12 months (as a percent)		3.00%
Prepayment fee, After first 12 months before 36 months (as a percent)		2.00%
Prepayment fee, after 36 months (as a percent)		1.00%
Maximum amount outstanding for covenant		$ 100,000,000
Minimum market capitalization		$ 1,200,000,000
Minimum restricted cash (as a percent)		50.00%
Minimum unrestricted cash (as a percent)		85.00%
Facility charge		$ 500,000
Payment of issuance costs		$ 1,500,000
Repayment Fee (as a percent)		4.95%
Accrued for final payment on debt			500,000	200,000
Unamortized deferred financing costs			1,200,000	1,400,000
Interest expense on debt obligations			4,500,000	$ 2,000,000
End of term charge			$ 2,200,000
Secured Debt \| Line of Credit \| Term Loan Facility \| Prime Rate
Debt Instrument [Line Items]
Variable rate (as a percent)		7.25%
Secured Debt \| Line of Credit \| Term Loan Facility \| Maximum \| Prime Rate
Debt Instrument [Line Items]
Variable rate (as a percent)		7.25%
Secured Debt \| Line of Credit \| Term Loan Facility, Tranche One
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 30,000,000
Secured Debt \| Line of Credit \| Term Loan Facility, Tranche Two
Debt Instrument [Line Items]
Maximum borrowing capacity		30,000,000			$ 15,000,000
Secured Debt \| Line of Credit \| Term Loan Facility, Tranche Three
Debt Instrument [Line Items]
Maximum borrowing capacity		115,000,000
Secured Debt \| Line of Credit \| Term Loan Facility, Tranche Four
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 25,000,000
Number of term loan advances \| advance		2
Secured Debt \| Line of Credit \| Term Loan Facility, Tranche Five
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 25,000,000
Number of term loan advances \| advance		2
Secured Debt \| Line of Credit \| Term Loan Facility, Tranche One and Two
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 60,000,000
Decrease in borrowing capacity	$ 30,000,000

Insider Trading Arrangements

3 Months Ended

12 Months Ended

Mar. 31, 2024

Trading Arrangements, by Individual

Material Terms of Trading Arrangement

During the three months ended March 31, 2024, each of the following officers adopted a “Rule 10b5-1 trading arrangement” (as defined in Item 408 of Regulation S-K) that is intended to satisfy the affirmative defense of Rule 10b5-1(c)

under the Exchange Act and our policies on insider trading:


Name & Title	Date Adopted (1)	Aggregate Number of Shares of Common Stock to be Purchased or Sold Pursuant to Trading Arrangement	Expiration Date(3)
Pamela Esposito Chief Business Officer	2/21/2024(2)	Indeterminable(4)	November 14, 2024
Konstantinos Xynos Chief Medical Officer	2/13/2024(2)	Indeterminable(4)	February 18, 2025
(1) Date of adoption of Rule 10b5-1 trading arrangements is in accordance with both the Company’s insider trading policy and applicable SEC rules and regulations. (2) The first trade pursuant to the Rule 10b5-1 trading arrangement will be, in accordance with both the Company’s insider trading policy and applicable SEC rules and regulations, on a date after the date of adoption of the Rule 10b5-1 trading arrangement. (3) The Rule 10b5-1 trading arrangement permits transactions through and including the earlier to occur of (a) the completion of all sales or (b) the date listed in the table. The arrangement also provides for automatic expiration in the event of liquidation, dissolution, bankruptcy, insolvency, or death of the adopting person. (4) The Rule 10b5-1 trading arrangement includes the sale of shares to be received upon future vesting of certain outstanding equity awards, net of any shares withheld by us to satisfy applicable taxes. The number of shares to be withheld, and thus the exact number of shares to be sold pursuant to the Rule 10b5-1 trading arrangement, can only be determined upon the occurrence of the future vesting events. For purposes of this disclosure, we have reported the gross number of shares to be received upon the future vesting of such equity awards, before subtracting any shares to be withheld by us to satisfy applicable taxes in connection with such future vesting events.

Other than those disclosed above, none of our directors or officers adopted, modified, or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” in each case as defined in Item 408 of Regulation S-K.

Non-Rule 10b5-1 Arrangement Adopted

false

Rule 10b5-1 Arrangement Terminated

false

Non-Rule 10b5-1 Arrangement Terminated

false

Pamela Esposito [Member]

Trading Arrangements, by Individual

Name

Pamela Esposito

Title

Chief Business Officer

Rule 10b5-1 Arrangement Adopted

true

Adoption Date

2/21/2024(2)

Arrangement Duration

267 days

Konstantinos Xynos [Member]

Trading Arrangements, by Individual

Name

Konstantinos Xynos

Title

Chief Medical Officer

Rule 10b5-1 Arrangement Adopted

true

Adoption Date

2/13/2024(2)

Arrangement Duration

371 days

Stockholders' equity - Schedule of Pre-funded Warrants (Details) - shares	1 Months Ended	12 Months Ended
	Dec. 31, 2022	Mar. 31, 2024	Mar. 31, 2023
Stock options, issued and outstanding
Class of Warrant or Right [Line Items]
Issuance of pre-funded warrants (in shares)		8,652,256	7,454,828
Restricted and performance stock units
Class of Warrant or Right [Line Items]
Issuance of pre-funded warrants (in shares)		2,397,890	1,351,280
Stock options and restricted stock units, future issuance
Class of Warrant or Right [Line Items]
Issuance of pre-funded warrants (in shares)		2,284,141	2,209,597
Employee stock purchase plan, available for future grants
Class of Warrant or Right [Line Items]
Issuance of pre-funded warrants (in shares)		2,738,208	2,076,603
Pre-IPO warrants to purchase common stock
Class of Warrant or Right [Line Items]
Issuance of pre-funded warrants (in shares)		497,344	497,344
Pre-funded warrants
Class of Warrant or Right [Line Items]
Issuance of pre-funded warrants (in shares)	4,200,000	5,281,616	9,484,238
Total shares of common stock reserved for future issuance
Class of Warrant or Right [Line Items]
Issuance of pre-funded warrants (in shares)		21,851,455	23,073,890

Accrued expenses and other current liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023
Accrued expenses and other current liabilities
Accrued research and development costs	$ 16,376	$ 11,261
Accrued compensation and benefits costs	13,906	9,909
Accrued professional fees	369	540
Other	3,330	2,994
Total	$ 33,981	$ 24,704

Pre-funded Warrants

12 Months Ended

Mar. 31, 2024

Equity [Abstract]

Pre-funded Warrants

Stockholders’ Equity

Common stock

As of March 31, 2024 and 2023, 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.

The Company had reserved for common stock for the exercise of outstanding stock options and the vesting of restricted share units, 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 10) and the exercise of the outstanding warrants to purchase shares of common stock as follows:


	March 31, 2024	March 31, 2023
Stock options, issued and outstanding	8,652,256	7,454,828
Restricted and performance stock units	2,397,890	1,351,280
Stock options and restricted stock units, future issuance	2,284,141	2,209,597
Employee stock purchase plan, available for future grants	2,738,208	2,076,603
Pre-IPO warrants to purchase common stock	497,344	497,344
Pre-funded warrants	5,281,616	9,484,238
Total shares of common stock reserved for future issuance	21,851,455	23,073,890

Undesignated preferred stock

As of March 31, 2024 and 2023, 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, 2024 and 2023.

ATM program

On August 11, 2020, the Company and SVB Leerink (the "Agent") entered into a sales agreement, which was subsequently amended on October 21, 2020 (as amended, the “2020 Sales Agreement”), pursuant to which the Company could sell, from time to time, at its option, up to an aggregate of $62.5 million of shares of the Company’s common stock through the Agent, as the Company’s sales agent.

During the fiscal year ended March 31, 2023, the Company settled transactions that occurred pursuant to the 2020 Sales Agreement, whereby the Company issued and sold an aggregate of 1,686,438 shares of its common stock, resulting in gross proceeds of $32.0 million, before deducting fees of $1.0 million.

On June 23, 2022, the 2020 Sales Agreement was terminated by the execution by the Company and the Agent of a new sales agreement (the “2022 Sales Agreement”). Under the 2022 Sales Agreement, the Company may sell, from time to time, at its option, up to an aggregate $100.0 million of shares of the Company's common stock through the Agent, as the Company's sales agent.

During the year ended March 31, 2023, pursuant to the 2022 Sales Agreement, the Company issued and sold an aggregate of 340,000 shares of its common stock, resulting in gross proceeds of $6.7 million, before deducting fees of $0.3 million.

On August 3, 2023, the 2022 Sales Agreement was terminated by the execution by the Company and Leerink Partners LLC (formerly known as SVB Securities LLC) (the "Current Agent") of a new sales agreement, which was subsequently amended on May 16, 2024 (as so amended, the "2023 Sales Agreement"). Under the 2023 Sales Agreement, the Company may sell, from time to time, at its option, up to an aggregate of $100.0 million of share of the Company's common stock, $0.001 par value shares (the "Shares"), through the Current Agent, as the Company's sales agent.

Any Shares to be offered and sold under the 2023 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 if authorized by the Company, in negotiated transactions or block trades, and (ii) pursuant to a registration statement on Form S-3 filed by the Company with the Securities and Exchange Commission on August 3, 2023, as amended for an offering 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 2023 Sales Agreement, the Current Agent will use 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 Current Agent a commission of up to 3.0% of the gross proceeds from the sale of the Shares. The Company has also agreed to provide the Current Agent with customary indemnification rights.

During the year ended March 31, 2024, the Company did not issue or sell any shares under the 2023 Sales Agreement. The Company cannot provide any assurances that it will issue any additional Shares pursuant to the 2023 Sales Agreement.

Equity offerings

In December 2022, the Company completed a public offering of (a) 6,810,658 shares of the Company’s common stock, inclusive of the underwriters 30-day option to purchase up to an additional 1,436,172 shares of the Company’s common stock, at a public offering price of $23.50 per share and (b) pre-funded warrants to purchase 4,200,000 shares of the Company’s common stock at a public offering price of $23.4999 per warrant. The Company received aggregate net proceeds of approximately $242.6 million after deducting underwriting discounts, commissions and other offering expenses payable by the Company of approximately $16.1 million.

Pre-funded Warrants

Between November 2019 and December 2022, the Company completed public offerings including an option to purchase pre-funded warrants to purchase shares of the Company's common stock. As of March 31, 2024, the total amount of pre-funded warrants issued was 9,484,238 of which 4,202,622 have been exercised and 5,281,616 remained outstanding.

The remaining outstanding pre-funded warrants described above are exercisable at any time after the date of issuance. Unless otherwise modified by a holder of a pre-funded warrant, no holder may exercise a pre-funded warrant if such 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 a pre-funded warrant may increase or decrease this percentage up to 19.99% by providing at least 61 days’ prior notice to the Company.

The 5,281,616 shares of the Company's common stock underlying the above described pre-funded warrants, are not included in the number of issued and outstanding shares of the Company’s common stock outstanding as reported on the consolidated balance sheet, though they are included in the Company's annual pool increase calculation as well as the weighted average outstanding common stock in the calculation of basic and diluted net loss per share, as noted below in Note 11.

During the year ended March 31, 2024, a holder of the Company's pre-funded warrants exercised 4,202,622 of its pre-funded warrants and the Company issued 4,202,622 shares of common stock in exchange thereof.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

+ Details

Benefit plans	12 Months Ended
Benefit plans	Mar. 31, 2024
Retirement Benefits [Abstract]
Benefit plans	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, 2024 and 2023, the Company made contributions totaling $2.1 million and $1.3 million, 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.

- Definition

The entire disclosure for retirement benefits.

+ References

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-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480266/715-60-50-3

+ Details

Property, plant and equipment, net (Tables)

12 Months Ended

Mar. 31, 2024

Property, Plant and Equipment [Abstract]

Schedule of property, plant and equipment, net

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 and software			3 years
Plant, manufacturing and laboratory equipment			5 years
Capitalized software			3 to 5 years
Leasehold improvements			Lesser of lease term or 10 years

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


	March 31, 2024		March 31, 2023

Office equipment	$	1,464	$	1,240
Computer equipment	1,975		1,806
Plant and laboratory equipment	10,423		9,186
Leasehold improvements	1,886		1,706
Capitalized software	3,515		—
Construction in progress	1,117		783
	20,380		14,721
Less: Accumulated depreciation and amortization	(9,897)		(7,242)
	$	10,483	$	7,479

Income taxes - Reconciliation of the U.S federal statutory income tax rate (Details)	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Reconciliation of the U.S federal statutory income tax rate
U.S. federal statutory income tax rate	(21.00%)	(21.00%)
State taxes, net of federal benefit	(0.30%)	(0.60%)
Research and development	0.70%	1.00%
Stock compensation	3.00%	(0.10%)
Foreign tax rate differential	(3.60%)	1.80%
Change in tax rates	0.00%	(6.00%)
Change in valuation allowance	21.40%	23.60%
Other	0.00%	1.50%
Effective income tax rate	0.20%	0.20%

Income taxes - Net loss before income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest [Abstract]
United States	$ (19,367)	$ (18,367)
United Kingdom	(196,019)	(155,629)
Total	$ (215,386)	$ (173,996)

- Definition

Amount after tax of income (loss) from continuing operations attributable to the parent.

+ References

+ Details

Stockholders' equity - Equity offerings (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2022	Mar. 31, 2024	Mar. 31, 2023
Class of Warrant or Right [Line Items]
Proceeds from issuance of common stock, net of underwriting fees and discounts	$ 242,600	$ 0	$ 149,854
Follow-on public offering
Class of Warrant or Right [Line Items]
Number of shares issued (in shares)	6,810,658
Shares issued during period (in shares)	1,436,172
Pre-funded warrants
Class of Warrant or Right [Line Items]
Sale of stock, purchase period	30 days
Sale of stock, price per share (in dollars per share)	$ 23.50
Issuance of pre-funded warrants (in shares)	4,200,000	5,281,616	9,484,238
Public offering price (in dollars per share)	$ 23.4999
Underwriter rights
Class of Warrant or Right [Line Items]
Underwriting discounts, commissions and other offering expenses	$ 16,100

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net loss	$ (215,794)	$ (174,284)

- Definition

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

+ References

+ Details

Pre-funded Warrants - Narrative (Details) - shares	1 Months Ended		12 Months Ended
Pre-funded Warrants - Narrative (Details) - shares	Dec. 31, 2022	Oct. 31, 2020	Mar. 31, 2024	Mar. 31, 2023
Pre-funded warrants
Class of Warrant or Right [Line Items]
Warrants exercised (in shares)			4,202,622
Common stock
Class of Warrant or Right [Line Items]
Shares issued during period (in shares)			4,202,622
Pre-funded warrants
Class of Warrant or Right [Line Items]
Total amount of pre-funded warrants issued, including exercised (in shares)			9,484,238
Issuance of pre-funded warrants (in shares)	4,200,000		5,281,616	9,484,238
Maximum percentage of holding for exercise warrants		9.99%
Maximum percentage of increase (decrease) of holding for exercise warrants (as a percent)		19.99%

Commitments and contingencies - Components of lease expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Finance lease costs:
Amortization of right-to-use asset	$ 2,428	$ 2,428
Interest on lease liabilities	2,163	2,197
Operating lease costs	1,122	1,018
Total lease cost	$ 5,713	$ 5,643

Commitments and contingencies - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Lessee, Lease, Description [Line Items]
Minimum payments committed to manufacturing organization	$ 0.9	$ 1.0
Minimum
Lessee, Lease, Description [Line Items]
Lease term (in years)	5 years
Lease term (in years)	5 years
Maximum
Lessee, Lease, Description [Line Items]
Lease term (in years)	15 years
Lease term (in years)	15 years

Stockholders' equity

12 Months Ended

Mar. 31, 2024

Stockholders' Equity Note [Abstract]

Stockholders' equity

Stockholders’ Equity

Common stock


	March 31, 2024	March 31, 2023
Stock options, issued and outstanding	8,652,256	7,454,828
Restricted and performance stock units	2,397,890	1,351,280
Stock options and restricted stock units, future issuance	2,284,141	2,209,597
Employee stock purchase plan, available for future grants	2,738,208	2,076,603
Pre-IPO warrants to purchase common stock	497,344	497,344
Pre-funded warrants	5,281,616	9,484,238
Total shares of common stock reserved for future issuance	21,851,455	23,073,890

Undesignated preferred stock

ATM program

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.

Equity offerings

Pre-funded Warrants

- Definition

The entire disclosure for equity.

+ References

+ Details

Stockholders' equity (Tables)

12 Months Ended

Mar. 31, 2024

Stockholders' Equity Note [Abstract]

Schedule of stockholders equity


	March 31, 2024	March 31, 2023
Stock options, issued and outstanding	8,652,256	7,454,828
Restricted and performance stock units	2,397,890	1,351,280
Stock options and restricted stock units, future issuance	2,284,141	2,209,597
Employee stock purchase plan, available for future grants	2,738,208	2,076,603
Pre-IPO warrants to purchase common stock	497,344	497,344
Pre-funded warrants	5,281,616	9,484,238
Total shares of common stock reserved for future issuance	21,851,455	23,073,890

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023
Current assets:
Cash and cash equivalents	$ 74,457	$ 146,590
Short-term investments	346,211	436,796
Research and development incentives receivable	4,922	2,939
Prepaid expenses and other current assets	8,077	6,278
Total current assets	433,667	592,603
Property, plant and equipment, net	10,483	7,479
Restricted cash	1,700	1,636
Right-to-use asset – operating leases	4,635	5,208
Right-to-use asset – financing leases	37,237	39,665
Total assets	487,722	646,591
Current liabilities:
Accounts payable	2,578	5,364
Accrued expenses and other current liabilities	33,981	24,704
Operating lease liabilities, current	1,161	1,118
Financing lease liabilities, current	2,718	2,639
Total current liabilities	40,438	33,825
Operating lease liabilities, non-current	3,771	4,389
Financing lease liabilities, non-current	23,410	23,965
Long term debt, net of discount	44,809	28,648
Other liabilities, non-current	786	472
Total liabilities	113,214	91,299
Commitments and contingencies (Note 13)
Stockholders’ equity:
Common stock, $0.001 par value; 150,000,000 shares authorized as of March 31, 2024 and March 31, 2023; 61,415,105 and 56,676,313 shares issued and outstanding as of March 31, 2024 and March 31, 2023, respectively	61	57
Additional paid-in capital	1,070,874	1,034,994
Accumulated deficit	(701,282)	(485,488)
Accumulated other comprehensive income (loss)	4,855	5,729
Total stockholders’ equity	374,508	555,292
Total liabilities and stockholders’ equity	$ 487,722	$ 646,591

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Parenthetical) - USD ($)	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Other comprehensive loss:
Net unrealized (loss) gain on short-term investments, net of tax	$ 0	$ 0

Long-term debt

12 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Long-term debt

Hercules Loan Agreement

On October 6, 2022, the Company entered into a Loan and Security Agreement (the “Loan Agreement”), with Hercules Capital, Inc., as administrative agent, collateral agent and as a lender (“Hercules”). Pursuant to the Loan Agreement, the Company can borrow term loans in an aggregate maximum principal amount of up to $200.0 million under multiple tranches (the “Term Loan Facility”). Under the Loan Agreement, the Company borrowed an initial amount of $30.0 million on the Closing Date, and at the Company's sole option, could have drawn, but did not draw, an additional $30.0 million on or prior to September 30, 2023. The Company can also draw as additional term loan advances in an aggregate principal amount of up to $115.0 million during the term of the Term Loan Facility subject to achievement of specified performance milestones, and two additional term loan advances up to an aggregate principal amount of $25.0 million subject to certain terms and conditions, on or prior to the end of the interest-only period. The Company intends to use the proceeds of the Term Loan Facility for working capital and general corporate purposes.

The Loan Agreement was subsequently amended (the "Amendment") on June 28, 2023 pursuant to which the Company agreed to draw an initial term loan advance in an aggregate principal amount not less than $30.0 million, provided that the aggregate amount of the term loan advances made under tranche 1 do not exceed $30.0 million, which reflects a decrease of $30.0 million from the $60.0 million in the original Loan Agreement for tranche 1. The total amount of the Loan Agreement, as well as the outstanding balance of the loan, is unchanged, but the option to borrow additional funds were redistributed from tranche 1 to tranche 2. The impact of this amendment is not a modification, as it does not relate to outstanding debt, but is rather an amendment that provides for a future potential benefit. There was no material impact to the financial statements as a result of the Amendment.

A second amendment was made to the Loan Agreement (the "Second Amendment") on December 22, 2023 pursuant to which the Company agreed to draw a term loan advance in an aggregate principal amount not less than $15.0 million, provided that the aggregate amount of the term loan advances made under tranche 2 do not exceed $15.0 million on or prior to December 31, 2023. The Second Amendment re-allocated the total future consideration of the Loan Agreement to the future tranches extending through September 2026, subject to the terms and conditions of the Loan Agreement. The Second Amendment did not change the total aggregate maximum principal amount to be drawn under the Loan Agreement, which remains as up to $200.0 million. The Company evaluated the Second Amendment as a modification under relevant accounting guidance, and based on that analysis and the immaterial change in cash flows on current outstanding debt, it was determined that there was no material accounting impact. Upon closing of the Second Amendment, the Company drew down the tranche 2 amount of $15.0 million.

The Term Loan Facility will mature on October 1, 2027 (the “Maturity Date”). The outstanding principal balance of the Term Loan Facility bears interest payable in cash at a floating rate per annum equal to the greater of (i) 7.25% and (ii) the sum of the Prime Rate (which is capped at 7.25%) and 1.75%. Accrued interest is payable monthly following the funding of each term loan advance. In addition, the principal balance of the Term Loan Facility will bear “payment-in-kind” interest at the rate of 1.50% (“PIK Interest”), which PIK Interest will be added to the outstanding principal balance of the Term Loan Facility on each interest payment date.

Borrowings under the Loan Agreement are repayable in monthly interest-only payments through September 2026. After the interest-only payment period, borrowings under the Loan Agreement are repayable in equal monthly payments of principal and accrued interest until October 2027. At the Company's option, the Company may prepay all or a portion of the outstanding borrowings, subject to a prepayment fee of 3.0% of the principal amount if prepayment occurs during the 12 months following the Closing Date, 2.0% after 12 months following the Closing Date but prior to 36 months following the Closing Date, and 1.0% thereafter.

The Loan Agreement contains customary facility fees, events of default and representations, warranties and affirmative and negative covenants, including a financial covenant requiring the Company to maintain certain levels of cash in accounts subject to a control agreement in favor of the Agent (the “Unrestricted Cash”) at all times commencing on January 1, 2024. In addition, the Loan Agreement also contains a financial covenant that beginning on the later of (i) July 1, 2024 and (ii) the date on which the aggregate outstanding principal amount of the Term Loan Facility is equal to or greater than $100.0 million, the Company is required to satisfy one of the following requirements: (1) achieve a minimum amount of trailing three-month net product revenue tested on a monthly basis, (2) maintain a market capitalization in excess of $1.2 billion and Unrestricted Cash in an amount no less than 50% of the outstanding amount under the Term Loan Facility, or (3) maintain Unrestricted Cash in an amount no less than 85% of the outstanding amount under the Term Loan Facility.

The Company paid a $0.5 million facility charge and incurred debt issuance costs of $1.5 million upon closing of the Loan Agreement. The Loan Agreement also provides for a final payment, payable upon maturity or the repayment of the obligations in full or in part (on a pro rata basis), equal to 4.95% of the aggregate principal amount of Term Loans advanced to the Borrower and repaid on such date, which is being accrued on the Company's consolidated balance sheet. As of March 31, 2024 and 2023, the amount accrued for the final payment was $0.5 million and $0.2 million, respectively.

Unamortized debt issuance costs are recorded as a reduction of the carrying amount on the term loan and amortized as interest expense using the effective-interest method. In addition, unamortized deferred financing costs of $1.2 million and $1.4 million were recorded in other assets as of March 31, 2024 and 2023, respectively, related to the Company's right to borrow additional amounts from Hercules in the future and amortized to interest expense over the relevant draw period on a straight-line basis. Interest expense for the twelve months ended March 31, 2024 and 2023 was $4.5 million and $2.0 million, respectively.

The summary of obligations under the term loan as of March 31, 2024 and 2023 consisted of the following (in thousands):


	March 31, 2024		March 31, 2023
Principal loan balance	$	45,749	$	30,222
Facility charge and diligence fee	(266)		(315)
Unamortized issuance costs	(1,191)		(1,410)
Accumulated end of term fee	517		151
Long term debt, net	$	44,809	$	28,648

The annual principal payments by fiscal year due under the Loan Agreement as of March 31, 2024 were as follows:


	March 31, 2024
2025	—
2026	—
2027	20,145
Thereafter	27,769
Total	$	47,914

The table of future payments of long-term debt excludes the end of term charge of $2.2 million, which is due upon the maturity of the loan.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//470/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

+ Details

Geographic information (Details) $ in Thousands	12 Months Ended
Geographic information (Details) $ in Thousands	Mar. 31, 2024 USD ($) region	Mar. 31, 2023 USD ($)
Segments, Geographical Areas [Abstract]
Number of operating geographic regions \| region	2
Geographic information
Long-lived assets	$ 10,483	$ 7,479
United States
Geographic information
Long-lived assets	8,992	5,836
United Kingdom
Geographic information
Long-lived assets	$ 1,491	$ 1,643

Commitments and contingencies - Additional information related to leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Leases
Right-to-use operating lease asset	$ 4,635	$ 5,208
Right-to-use finance lease asset	37,237	39,665
Total lease assets	41,872	44,873
Operating lease liabilities, current	1,161	1,118
Finance lease liabilities, current	2,718	2,639
Operating lease liabilities, non-current	3,771	4,389
Financing lease liabilities, non-current	23,410	23,965
Total lease liabilities	31,060	32,111
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	1,059	1,014
Operating cash flows from finance leases	2,163	2,197
Financing cash flows from finance leases	476	365
Right-to-use asset obtained in exchange for new operating lease liabilities	$ 0	$ 290
Weighted-average remaining lease term – operating leases	5 years 7 months 6 days	6 years 7 months 6 days
Weighted-average remaining lease term – financing leases	15 years 3 months 18 days	16 years 3 months 18 days
Weighted-average discount rate – operating leases	10.30%	10.30%
Weighted-average discount rate – financing leases	8.30%	8.30%

Net loss per share (Tables)

12 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

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

The following table sets forth the computation of the Company’s basic and diluted net loss per share attributable to common stockholders (in thousands, except per share amounts):


	Year ended March 31,
	2024		2023
Numerator:
Net loss	$	(215,794)	$	(174,284)
Denominator:
Weighted average common shares outstanding, basic and diluted	66,569,894		58,213,010
Net loss per share, basic and diluted	$	(3.24)	$	(2.99)

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

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 for the periods indicated because including them would have had an anti-dilutive effect:


	Year ended March 31,
	2024	2023
Options to purchase common stock	8,652,256	7,454,828
Unvested restricted and performance stock units	2,397,890	1,351,280
Warrants to purchase common stock	497,344	497,344