Immunovant (IMVT) 10-Q 9 Nov 23 2024 Q2 Quarterly report Financial data

Cover

Cover - shares	6 Months Ended
	Sep. 30, 2023	Nov. 03, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Entity File Number	001-38906
Entity Registrant Name	IMMUNOVANT, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	83-2771572
Entity Address, Address Line One	320 West 37th Street
Entity Address, City or Town	New York,
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10018
City Area Code	917
Local Phone Number	580-3099
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	IMVT
Security Exchange Name	NASDAQ
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
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		144,661,930
Entity Central Index Key	0001764013
Amendment Flag	false
Current Fiscal Year End Date	--03-31
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2024

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2023	Mar. 31, 2023
Current assets:
Cash and cash equivalents	$ 269,928	$ 376,532
Accounts receivable	1,421	700
Prepaid expenses and other current assets	19,828	27,101
Total current assets	291,177	404,333
Operating lease right-of-use assets	589	1,172
Property and equipment, net	304	333
Total assets	292,070	405,838
Current liabilities:
Accounts payable	7,511	1,353
Accrued expenses	32,134	40,771
Current portion of operating lease liabilities	614	1,173
Total current liabilities	40,259	43,297
Operating lease liabilities, net of current portion	0	47
Total liabilities	40,259	43,344
Commitments and contingencies (Note 9)
Stockholders’ equity:
Common stock, par value $0.0001 per share, 500,000,000 shares authorized, 131,442,024 shares issued and outstanding at September 30, 2023 and 500,000,000 shares authorized, 130,329,863 shares issued and outstanding at March 31, 2023	13	13
Additional paid-in capital	950,231	927,976
Accumulated other comprehensive income	513	852
Accumulated deficit	(698,946)	(566,347)
Total stockholders’ equity	251,811	362,494
Total liabilities and stockholders’ equity	292,070	405,838
Series A  preferred stock
Stockholders’ equity:
Preferred stock	0	0
Preferred Stock
Stockholders’ equity:
Preferred stock	$ 0	$ 0

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2023	Mar. 31, 2023
Preferred stock, par value (in dollars per share)	$ 0.0001
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, authorized (in shares)	500,000,000	500,000,000
Common stock, outstanding (in shares)	131,442,024	130,329,863
Common stock, issued (in shares)	131,442,024	130,329,863
Series A  preferred stock
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, authorized (in shares)	10,000	10,000
Preferred stock, issued (in shares)	10,000	10,000
Preferred stock, outstanding (in shares)	10,000	10,000
Preferred Stock
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, authorized (in shares)	10,000,000	10,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Operating expenses:
Research and development	$ 47,959	$ 37,739	$ 98,534	$ 66,168
Acquired in-process research and development	0	0	12,500	0
General and administrative	13,841	11,875	29,243	23,821
Total operating expenses	61,800	49,614	140,277	89,989
Interest income	(3,572)	(1,154)	(7,637)	(1,154)
Other income, net	(20)	(793)	(484)	(1,147)
Loss before provision for income taxes	(58,208)	(47,667)	(132,156)	(87,688)
Provision for income taxes	454	261	443	613
Net loss	$ (58,662)	$ (47,928)	$ (132,599)	$ (88,301)
Net loss per common share - basic (in dollars per share)	$ (0.45)	$ (0.41)	$ (1.01)	$ (0.76)
Net loss per common share - diluted (in dollars per share)	$ (0.45)	$ (0.41)	$ (1.01)	$ (0.76)
Weighted-average common shares outstanding – basic (in shares)	131,155,642	116,572,820	130,872,717	116,630,076
Weighted-average common shares outstanding – diluted (in shares)	131,155,642	116,572,820	130,872,717	116,630,076

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Statement of Comprehensive Income [Abstract]
Net loss	$ (58,662)	$ (47,928)	$ (132,599)	$ (88,301)
Other comprehensive (loss) income:
Foreign currency translation adjustments	69	(974)	339	(1,641)
Total other comprehensive (loss) income	69	(974)	339	(1,641)
Comprehensive loss	$ (58,593)	$ (48,902)	$ (132,260)	$ (89,942)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Series A  preferred stock	Common stock	Additional paid-in capital	Accumulated other comprehensive income (loss)	Accumulated deficit
Beginning balance (in shares) at Mar. 31, 2022		10,000	116,482,899
Beginning balance at Mar. 31, 2022	$ 469,825	$ 0	$ 12	$ 824,796	$ 404	$ (355,387)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised and restricted stock units vested and settled (in shares)			41,259
Stock options exercised and restricted stock units vested and settled	21			21
Capital contribution – stock-based compensation	132			132
Stock-based compensation	7,555			7,555
Foreign currency translation adjustments	(667)				(667)
Net loss	(40,373)					(40,373)
Ending balance (in shares) at Jun. 30, 2022		10,000	116,524,158
Ending balance at Jun. 30, 2022	436,493	$ 0	$ 12	832,504	(263)	(395,760)
Beginning balance (in shares) at Mar. 31, 2022		10,000	116,482,899
Beginning balance at Mar. 31, 2022	469,825	$ 0	$ 12	824,796	404	(355,387)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(88,301)
Ending balance (in shares) at Sep. 30, 2022		10,000	116,614,088
Ending balance at Sep. 30, 2022	395,748	$ 0	$ 12	840,661	(1,237)	(443,688)
Beginning balance (in shares) at Jun. 30, 2022		10,000	116,524,158
Beginning balance at Jun. 30, 2022	436,493	$ 0	$ 12	832,504	(263)	(395,760)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Capital contribution – stock-based compensation	106			106
Stock-based compensation	8,051			8,051
Foreign currency translation adjustments	(974)				(974)
Restricted stock units vested and settled (in shares)			89,930
Net loss	(47,928)					(47,928)
Ending balance (in shares) at Sep. 30, 2022		10,000	116,614,088
Ending balance at Sep. 30, 2022	395,748	$ 0	$ 12	840,661	(1,237)	(443,688)
Beginning balance (in shares) at Mar. 31, 2023		10,000	130,329,863
Beginning balance at Mar. 31, 2023	362,494	$ 0	$ 13	927,976	852	(566,347)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised and restricted stock units vested and settled (in shares)			235,566
Stock options exercised and restricted stock units vested and settled	890			890
Capital contribution – stock-based compensation	35			35
Stock-based compensation	10,653			10,653
Foreign currency translation adjustments	(270)				(270)
Net loss	(73,937)					(73,937)
Ending balance (in shares) at Jun. 30, 2023		10,000	130,565,429
Ending balance at Jun. 30, 2023	299,865	$ 0	$ 13	939,554	582	(640,284)
Beginning balance (in shares) at Mar. 31, 2023		10,000	130,329,863
Beginning balance at Mar. 31, 2023	362,494	$ 0	$ 13	927,976	852	(566,347)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(132,599)
Ending balance (in shares) at Sep. 30, 2023		10,000	131,442,024
Ending balance at Sep. 30, 2023	251,811	$ 0	$ 13	950,231	513	(698,946)
Beginning balance (in shares) at Jun. 30, 2023		10,000	130,565,429
Beginning balance at Jun. 30, 2023	299,865	$ 0	$ 13	939,554	582	(640,284)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised and restricted stock units vested and settled (in shares)			876,595
Stock options exercised and restricted stock units vested and settled	148			148
Capital contribution – stock-based compensation	28			28
Stock-based compensation	10,501			10,501
Foreign currency translation adjustments	(69)				(69)
Net loss	(58,662)					(58,662)
Ending balance (in shares) at Sep. 30, 2023		10,000	131,442,024
Ending balance at Sep. 30, 2023	$ 251,811	$ 0	$ 13	$ 950,231	$ 513	$ (698,946)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities
Net loss	$ (132,599)	$ (88,301)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	21,217	15,844
Depreciation on property and equipment	109	90
Non-cash lease expense	583	560
Changes in operating assets and liabilities:
Accounts receivable	(703)	8,817
Prepaid expenses and other current assets	7,240	(10,126)
Accounts payable	6,096	(10,967)
Accrued expenses	(8,767)	(1,357)
Operating lease liabilities	(606)	(565)
Net cash used in operating activities	(107,430)	(86,005)
Cash flows from investing activities
Purchase of property and equipment	(79)	(73)
Net cash used in investing activities	(79)	(73)
Cash flows from financing activities
Proceeds from stock options exercised	1,038	21
Net cash provided by financing activities	1,038	21
Effect of exchange rate changes on cash and cash equivalents	(133)	(1,987)
Net change in cash and cash equivalents	(106,604)	(88,044)
Cash and cash equivalents – beginning of period	376,532	493,817
Cash and cash equivalents – end of period	$ 269,928	$ 405,773

Description of Business and Liq

Description of Business and Liquidity	6 Months Ended
	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Liquidity	Description of Business and Liquidity [A] Description of Business Immunovant, Inc. (together with its wholly owned subsidiaries, the “Company” or “Immunovant”) is a clinical-stage biopharmaceutical company dedicated to enabling normal lives for people with autoimmune diseases. The Company’s innovative product pipeline includes batoclimab, formerly referred to as IMVT-1401, and IMVT-1402, both of which are novel, fully human, monoclonal antibodies that target the neonatal fragment crystallizable receptor (“FcRn”). Designed to be optimized as a simple, subcutaneous injection with dosing that the Company believes can be tailored based on disease severity and stage, batoclimab has been observed to reduce immunoglobulin G (“IgG”) antibodies that cause inflammation and disease. Likewise, IMVT-1402 has also been observed to reduce IgG antibody levels. The Company has determined that it has one operating and reporting segment. [B] Liquidity The Company has incurred significant losses and negative cash flows from operations since its inception. As of September 30, 2023, the Company’s cash and cash equivalents totaled $269.9 million and its accumulated deficit was $698.9 million . The Company has not generated any revenues to date and does not anticipate generating any revenues unless and until it successfully completes development and obtains regulatory approval for batoclimab, IMVT-1402 or any future product candidate. Management expects to incur additional losses in the future to fund its operations and conduct product research and development and recognizes the need to raise additional capital to fully implement its business plan. The Company intends to raise such additional capital through the issuance of equity securities, debt financings or other sources in order to further implement its business plan. However, if such financing is not available at adequate levels, the Company will need to reevaluate its operating plan and may be required to delay the development of its product candidates. The Company currently expects that its existing cash and cash equivalents as of September 30, 2023 will be sufficient to fund its operating expenses and capital expenditure requirements for at least the next 12 months from the date these unaudited condensed consolidated financial statements are issued.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies [A] Basis of Presentation The Company’s fiscal year ends on March 31 and its first three fiscal quarters end on June 30, September 30, and December 31, respectively. The accompanying condensed consolidated financial statements are unaudited. The unaudited condensed consolidated financial statements of the Company have been prepared in accordance with generally accepted accounting principles in the United States (“U.S. GAAP”) and follow the requirements of the Securities and Exchange Commission (“SEC”) for interim financial reporting. Accordingly, they do not include all of the information and disclosures required by U.S. GAAP for complete financial statements as certain footnotes or other financial information that are normally required by U.S. GAAP can be condensed or omitted. The unaudited condensed consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements. The unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. The Company has no unconsolidated subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. Certain amounts in the consolidated financial statements of the prior year have been reclassified to conform to current year presentation. Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”). In the opinion of management, the unaudited condensed consolidated financial statements include all normal and recurring adjustments that are considered necessary for the fair statement of results for the interim periods. The results for the three and six months ended September 30, 2023 are not necessarily indicative of those expected for the year ending March 31, 2024 or for any future period. The condensed consolidated balance sheet as of March 31, 2023 included herein was derived from the audited consolidated financial statements as of that date. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements included in the Company’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission (“SEC”) on May 22, 2023. [B] Use of Estimates The preparation of unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the unaudited condensed consolidated financial statements and accompanying notes. The Company regularly evaluates estimates and assumptions related to assets, liabilities, stock-based compensation, litigation accruals, clinical trial accruals, operating leases, research and development costs and income taxes. The Company bases its estimates and assumptions on historical experience and on various other factors that it believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ from those estimates. Additionally, the Company assessed the impact of the post-COVID-19 environment, geopolitical tensions and global slowdown of economic activity, changes in inflation, rising interest rates and a potential recession in the U.S. on its operations and financial results as of September 30, 2023 and through the issuance of these unaudited condensed consolidated financial statements. The Company’s analysis was informed by the facts and circumstances as they were known to the Company. This assessment considered the impact that these uncertainties may have on financial estimates and assumptions that affect the reported amounts of assets and liabilities and expenses. [C] Risks and Uncertainties The Company is subject to risks common to early-stage companies in the biopharmaceutical industry including, but not limited to, uncertainties related to clinical effectiveness of products, commercialization of products, regulatory approvals, dependence on key products, key personnel and third-party service providers such as contract research organizations (“CROs”), protection of intellectual property rights and the ability to make milestone, royalty or other payments due under any license, collaboration or supply agreements. [D] Concentration of Credit Risk Financial instruments that potentially subject the Company to concentration of credit risk include cash and cash equivalents. As of September 30, 2023, the cash and cash equivalents balance is kept in banking institutions that the Company believes are of high credit quality and are in excess of federally insured levels. The Company maintains its cash and cash equivalents with accredited financial institutions and accordingly, such funds are subject to minimal credit risk. The Company has not experienced any losses on its cash and cash equivalents. [E] Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less from the date of purchase to be cash equivalents. As of September 30, 2023 and March 31, 2023, cash and cash equivalents included $254.1 million and $346.2 million, respectively, of money market funds invested in high-quality, short-term securities that are issued and guaranteed by the U.S. government and its agencies that are classified within Level 1 of the fair value hierarchy because they are valued using quoted market prices. [F] Research and Development Expenses Research and development costs with no alternative future use are expensed as incurred. Research and development expenses primarily consist of employee-related costs and expenses from third parties who conduct research and development activities (including manufacturing) on behalf of the Company. The Company accrues costs for clinical trial activities based upon estimates of the services received and related expenses incurred that have yet to be invoiced by CROs. In making these estimates, the Company considers various factors, including status and timing of services performed, the number of patients enrolled and the rate of patient enrollment. The Company accrues costs for non-clinical studies and contract manufacturing activities over the service periods specified in the contracts and are adjusted as necessary based upon an ongoing review of the level of effort and costs actually incurred. The estimate of the work completed is developed through discussions with internal personnel and external services providers as to the progress toward completion of the services and the agreed-upon fee to be paid for such services. As actual costs become known, the accrued estimates are adjusted. Such estimates are not expected to be materially different from amounts actually incurred. The Company participates in cost-sharing arrangements with third parties whereas the third parties have agreed to share a portion of the costs incurred by the Company, related to batoclimab drug manufacturing and clinical trials. The Company records the third parties’ share of the costs as a reduction of research and development expenses and an increase to accounts receivable in the accompanying unaudited condensed consolidated financial statements based on actual amounts incurred by the Company and billable to the third parties. These cost-sharing arrangements do not contemplate any future revenue-generating activity or global commercialization efforts of batoclimab benefiting any of the parties. [G] Acquired In-Process Research and Development Expenses Acquired in-process research and development (“IPR&D”) expenses include payments made or due in connection with license agreements upon the achievement of development and regulatory milestones. The Company evaluates in-licensed agreements for IPR&D projects to determine if it meets the definition of a business and thus should be accounted for as a business combination. If the in-licensed agreement for IPR&D does not meet the definition of a business and the assets have not reached technological feasibility and therefore have no alternative future use, the Company expenses payments made under such license agreements as acquired in-process research and development expenses in its unaudited condensed consolidated statements of operations. Payments for milestones achieved and payments for a product license prior to regulatory approval of the product are expensed in the period incurred. Payments made in connection with regulatory and sales-based milestones will be capitalized and amortized to cost of product sales over the remaining useful life of the asset. [H] Stock-based Compensation Stock-based awards to employees and directors are valued at fair value on the date of the grant and that fair value is recognized as stock-based compensation expense over the requisite service period. The grant date fair value of the stock-based awards with graded vesting is recognized on a straight-line basis over the requisite service period, which is generally the vesting period of the respective awards. The Company values its stock options that only have service vesting requirements using the Black-Scholes option pricing model. Stock-based compensation related to restricted stock awards is based on the fair value of the Company’s common stock on the grant date. When determining the grant-date fair value of stock-based awards, management further considers whether an adjustment is required to the observable market price or volatility of the Company’s common stock that is used in the valuation as a result of material non-public information, if that information is expected to result in a material increase in share price. Certain assumptions need to be made with respect to utilizing the Black-Scholes option pricing model, including the expected life of the award, volatility of the underlying shares, the risk-free interest rate, expected dividend yield and the fair value of the Company’s common stock. Since the Company has limited option exercise history, it has generally elected to estimate the expected life of an award based upon the “simplified method” with the continued use of this method extended until such time the Company has sufficient exercise history. The expected share price volatility for the Company’s common stock is estimated by taking the average historical price volatility for the Company’s peers. The risk-free interest rate is based on the rates paid on securities issued by the U.S. Treasury with a term approximating the expected life of the equity award. As the Company has never paid and does not anticipate paying cash dividends on its common stock, the expected dividend yield is assumed to be zero. The Company accounts for pre-vesting award forfeitures when they occur. [I] Net Loss per Common Share Basic net loss per common share is computed by dividing net loss applicable to common stockholders by the weighted-average number of common stock outstanding during the period. Diluted net loss per common share is computed by dividing the net loss applicable to common stockholders by the diluted weighted-average number of common stock outstanding during the period. In periods in which the Company reports a net loss, all common stock equivalents are deemed anti-dilutive such that basic net loss per common share and diluted net loss per common share are equivalent. Potentially dilutive common stock has been excluded from the diluted net loss per common share computations in all periods presented because such securities have an anti-dilutive effect on net loss per common share due to the Company’s net loss. There are no reconciling items used to calculate the weighted-average number of total common stock outstanding for basic and diluted net loss per common share data. The following potentially dilutive securities have been excluded from the calculation of diluted net loss per share due to their anti-dilutive effect: Six Months Ended September 30, 2023 2022 Preferred stock as converted 10,000 10,000 Stock Options 13,372,356 11,185,963 Restricted stock units 4,036,663 4,587,727 Total 17,419,019 15,783,690 [J] Recent Accounting Pronouncements Recent authoritative guidance issued by the FASB (including technical corrections to the ASC), the American Institute of Certified Public Accountants, and the SEC did not, or are not expected to, have a material impact on the Company’s unaudited condensed consolidated financial statements and related disclosures.

Material Agreements

Material Agreements	6 Months Ended
	Sep. 30, 2023
Material Agreements [Abstract]
Material Agreements	Material Agreements License Agreement On December 19, 2017, Roivant Sciences GmbH (“RSG”), a wholly owned subsidiary of Roivant Sciences Ltd. (“RSL”), entered into a license agreement (the “HanAll Agreement”) with HanAll Biopharma Co., Ltd. (“HanAll”). Under the HanAll Agreement, RSG received (1) the non-exclusive right to manufacture and (2) the exclusive, royalty-bearing right to develop, import, use and commercialize the antibody referred to as batoclimab and certain back-up and next-generation antibodies (including IMVT-1402), and products containing such antibodies, in the United States of America (the “U.S.”), Canada, Mexico, the European Union, the United Kingdom, Switzerland, the Middle East, North Africa and Latin America (the “Licensed Territory”). In exchange for this license, RSG provided or agreed to provide the following consideration: • Upfront, non-refundable payment of $30.0 million; • Up to $20.0 million in shared (50%) research, development, and out-of-pocket costs incurred by HanAll; • Up to an aggregate of $420.0 million (after an aggregate amount of $32.5 million of milestone achievements as of September 30, 2023) upon the achievement of certain development, regulatory and sales milestones; and • Tiered royalties ranging from the mid-single digits to mid-teens percentage of net sales of licensed products, subject to standard offsets and reductions, on a product-by-product and country-by-country basis, until the later of (1) expiration of patent and regulatory exclusivity or (2) the 11th anniversary of the first commercial sale of such product in such country. On August 18, 2018, RSG entered into a sublicense agreement (the “Sublicense Agreement”) with Immunovant Sciences GmbH (“ISG”), a wholly-owned subsidiary of the Company, to sublicense this technology, as well as RSG’s know-how and patents necessary for the development, manufacture or commercialization of any compound or product that pertains to immunology. On December 7, 2018, RSG issued a notice to terminate the Sublicense Agreement with ISG and entered into an assignment and assumption agreement to assign to ISG all the rights, title, interest, and future obligations under the HanAll Agreement from RSG, including all rights to batoclimab and IMVT-1402 in the Licensed Territory, for an aggregate purchase price of $37.8 million. Under the HanAll Agreement, the parties may choose to collaborate on a research program directed to the research and development of next generation FcRn inhibitors in accordance with an agreed plan and budget. Each party has agreed that neither it nor certain of its affiliates will clinically develop or commercialize certain competitive products in the Licensed Territory. During the quarter ended June 30, 2023, the Company achieved its third and fourth development and regulatory milestones under the HanAll Agreement of $12.5 million, combined, which were recorded as acquired in-process research and development expenses in the accompanying unaudited condensed consolidated statement of operations for the six months ended September 30, 2023. As of September 30, 2023 and March 31, 2023, the Company did not have any additional amounts payable to HanAll for research and development costs incurred and reported to the Company pursuant to the HanAll Agreement. Product Service Agreement and Master Services Agreement On November 17, 2021, ISG entered into a Product Service Agreement (“PSA”) with Samsung Biologics Co., Ltd. (“Samsung”), pursuant to which Samsung will manufacture and supply the Company with batoclimab drug substance for commercial sale, if approved, and perform other manufacturing-related services with respect to batoclimab. The Company previously entered in a Master Services Agreement (“MSA”) with Samsung, dated April 30, 2021, which governs certain terms of the Company’s relationship with Samsung. Upon execution of the PSA, the Company committed to purchase process performance qualification batches of batoclimab and pre-approval inspection batches of batoclimab which may be used for regulatory submissions and, pending regulatory approval, commercial sale. In addition to these, the Company is obligated to purchase additional batches of batoclimab in the four-year period of 2026 through 2029. The PSA will continue until the later of December 31, 2029 or the completion of the services thereunder, unless the PSA is terminated earlier. If the Company makes a final decision to stop all development of batoclimab and all attempts to obtain regulatory approval for batoclimab, then the Company will have the right to terminate the PSA with 30 days’ written notice to Samsung as long as such notice is provided no later than January 2024. Upon such termination of the PSA, the Company will pay Samsung for non-cancellable service fees and costs that Samsung incurs and for all batches of batoclimab scheduled to be manufactured during the two-year period following such termination. In addition, either party may terminate the PSA on account of (i) the other party’s material breach of the PSA that is not cured within a specified period after the termination notice, (ii) the other party’s insolvency or bankruptcy, or (iii) certain force majeure events.

Accrued Expenses

Accrued Expenses	6 Months Ended
	Sep. 30, 2023
Payables and Accruals [Abstract]
Accrued Expenses	Accrued Expenses Accrued expenses consist of the following (in thousands): September 30, 2023 March 31, 2023 Research and development expenses $ 24,819 $ 31,321 Accrued bonuses 4,850 7,530 Legal and other professional fees 819 572 Other expenses 1,646 1,348 Total accrued expenses $ 32,134 $ 40,771

Related Party Transactions

Related Party Transactions	6 Months Ended
	Sep. 30, 2023
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Roivant Sciences, Inc. (“RSI”) and RSG Services Agreements In August 2018, the Company entered into amended and restated services agreements (the “Services Agreements”) with RSI and RSG, under which RSI and RSG agreed to provide services related to development, administrative and financial activities to the Company. Under each Services Agreement, the Company will pay or reimburse RSI or RSG, as applicable, for any expenses it, or third parties acting on its behalf, incurs for the Company. For any general and administrative and research and development activities performed by RSI or RSG employees, RSI or RSG, as applicable, will charge back the employee compensation expense plus a pre-determined mark-up. Employee compensation expense, inclusive of base salary and fringe benefits, is determined based upon the relative percentage of time utilized on Company matters. All other costs will be billed back at cost. The term of the Services Agreements will continue until terminated by the Company, RSI or RSG, as applicable, upon 90 days’ written notice. RSL Information Sharing and Cooperation Agreement In December 2018, the Company entered into an amended and restated information sharing and cooperation agreement (the “Cooperation Agreement”) with RSL. The Cooperation Agreement, among other things: (1) obligates the Company to deliver to RSL periodic financial statements and other information upon reasonable request and to comply with other specified financial reporting requirements; (2) requires the Company to supply certain material information to RSL to assist it in preparing any future SEC filings; and (3) requires the Company to implement and observe certain policies and procedures related to applicable laws and regulations. The Company has agreed to indemnify RSL and its affiliates and their respective officers, employees and directors against all losses arising out of, due to or in connection with RSL’s status as a stockholder under the Cooperation Agreement and the operations of or services provided by RSL or its affiliates or their respective officers, employees or directors to the Company or any of its subsidiaries, subject to certain limitations set forth in the Cooperation Agreement. No amounts have been paid or received under this agreement. Subject to specified exceptions, the Cooperation Agreement will terminate upon the earlier of (1) the mutual written consent of the parties or (2) the later of when RSL no longer (a) is required by U.S. GAAP to consolidate the Company’s results of operations and financial position, account for its investment in the Company under the equity method of accounting or, by any rule of the SEC, include the Company’s separate financial statements in any filings it may make with the SEC and (b) has the right to elect directors constituting a majority of the Company’s board of directors. RSI Subleases In June 2020, the Company entered into two sublease agreements with RSI for two floors of the building the Company currently occupies as its headquarters in New York. The subleases will expire on February 27, 2024 and April 29, 2024, respectively, and have scheduled rent increases each year. During the three months ended September 30, 2023 and 2022, the Company incurred $0.3 million in each period in rent expense under these operating leases. During the six months ended September 30, 2023 and 2022, the Company incurred $0.6 million in each period in rent expense under these operating leases. RSL Share Purchases In October 2023, RSL purchased 1,526,316 shares of the Company’s common stock pursuant to an underwritten public offering on the same terms as other investors in the offering, and 4,473,684 shares of the Company’s common stock in a private placement at the same price per share as investors in the public offering. See Note 10 – Subsequent Events.

Income Taxes

Income Taxes	6 Months Ended
	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company’s effective tax rates were (0.78)% and (0.55)% for the three months ended September 30, 2023 and 2022, respectively, and (0.34)% and (0.70)% for the six months ended September 30, 2023 and 2022. The Company’s effective rate is primarily driven by its jurisdictional earnings by location and a valuation allowance that eliminates the Company’s global net deferred tax assets. The Company assesses the realizability of its deferred tax assets at each balance sheet date based on available positive and negative evidence in order to determine the amount which is more likely than not to be realized and records a valuation allowance as necessary.

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Sep. 30, 2023
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity Series A Preferred Stock As of September 30, 2023, 10,000 shares of Series A preferred stock, par value $0.0001 per share, were outstanding and held by RSL. Each share of Series A preferred stock will automatically convert into one share of common stock at such time as the holder(s) of Series A preferred stock hold less than 25% of the total voting power of the Company’s outstanding shares. In the event of the Company’s liquidation, dissolution, or winding up, the holder(s) of the Series A preferred stock will receive first an amount per share equal to $0.01 and then will be entitled to share ratably in the assets legally available for distribution to all stockholders. Preferred Stock As of September 30, 2023, the Company has authorized 10,010,000 shares of preferred stock, par value $0.0001 per share. Other than the 10,000 shares of preferred stock designated as Series A preferred stock, there were no issued and outstanding shares of preferred stock as of September 30, 2023. Common Stock As of September 30, 2023, the Company has authorized 500,000,000 shares of common stock, par value $0.0001 per share and has 131,442,024 shares of common stock issued and outstanding. See Note 10 - Subsequent Events regarding the Company’s completion of an underwritten public offering and private placement in October 2023. The Company has reserved the following shares of common stock for issuance: September 30, 2023 March 31, 2023 Conversion of Series A preferred stock 10,000 10,000 Stock options outstanding 13,572,050 11,682,481 Restricted stock units outstanding 4,613,965 4,057,778 Equity awards available for future grants 2,245,595 590,317 Total 20,441,610 16,340,576 The reserved shares underlying stock options above include 199,694 stock options that were exercised but were not settled as of September 30, 2023. The reserved shares underlying restricted stock units above include 577,302 restricted stock units that vested but were not settled as of September 30, 2023. In addition, the Company has reserved 5,000,000 shares of its common stock that may be issued under its 2023 Inducement Plan as of September 30, 2023. See Note 8 – Stock-Based Compensation for further details.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation 2019 Equity Incentive Plan In December 2019, the Company’s stockholders approved the 2019 Equity Incentive Plan (the “2019 Plan”) and reserved 5,500,000 shares of common stock for issuance thereunder. The maximum number of shares of common stock that may be issued pursuant to the exercise of incentive options under the 2019 Plan is 16,500,000. The number of shares of common stock reserved for issuance under the 2019 Plan will automatically increase on April 1 of each year, continuing through April 1, 2029, by 4.0% of the total number of shares of common stock outstanding on the last day of the preceding month. On April 1, 2023, 5,213,194 shares of common stock were added to the 2019 Plan pool in accordance with the evergreen provision of the 2019 Plan. As of September 30, 2023, options to purchase 10,747,935 shares of common stock and 4,036,663 restricted stock units (“RSUs”) were outstanding under the 2019 Plan and 2,245,595 s hares of common stock remained available for future grant under the 2019 Plan. 2018 Equity Incentive Plan As of the effective date of the 2019 Plan, no further stock awards have been or will be made under the 2018 Equity Incentive Plan (the “2018 Plan”). As of September 30, 2023, options to purchase 2,624,421 shares of common stock were outstanding under the 2018 Plan. 2023 Inducement Plan On February 1, 2023, the Company's Board of Directors approved the adoption of the 2023 Inducement Plan (the “Inducement Plan”), which is to be used exclusively for grants of awards to individuals who were not previously employees or directors of the Company (or following a bona fide period of non-employment) as a material inducement to such individuals’ entry into employment with the Company, pursuant to Nasdaq Listing Rule 5635(c)(4). The Company has reserved 5,000,000 shares of its common stock that may be issued under the Inducement Plan. The terms and conditions of the Inducement Plan are substantially similar to those of the 2019 Plan. As of September 30, 2023, no awards were granted or outstanding under the Inducement Plan. Stock Option Activity A summary of the stock option activity under the Company’s equity incentive plans is as follows: Number of Stock Weighted- Remaining Aggregate Balance - March 31, 2023 11,682,481 $ 8.05 8.16 $ 88,919 Granted 2,080,263 15.13 Exercised (340,329) 7.98 Forfeited (46,432) 9.85 Expired (3,627) 8.62 Balance - September 30, 2023 13,372,356 $ 9.14 7.99 $ 391,077 Exercisable - September 30, 2023 6,648,722 $ 8.14 7.09 $ 201,142 The Company estimated the fair value of each option on the date of grant using the Black-Scholes option pricing model applying the weighted-average assumptions in the following table: Three Months Ended September 30, Six Months Ended September 30, 2023 2022 2023 2022 Risk-free interest rate 4.10% - 4.62% 2.89% - 4.11% 3.45% - 4.62% 2.74% - 4.11% Expected term, in years 6.11 6.11 6.11 6.11 Expected volatility 97.68% - 97.81% 88.53% - 88.78% 93.66% - 98.15% 87.12% - 88.78% Expected dividend yield —% —% —% —% Restricted Stock Unit Awards A summary of RSUs activity under the Company’s equity incentive plans is as follows: Number of RSUs Weighted- Average Grant Date Fair Value Nonvested as of March 31, 2023 3,692,979 $ 7.63 Issued 1,559,349 15.08 Vested (1,184,029) 6.55 Forfeited (31,636) 9.96 Nonvested as of September 30, 2023 4,036,663 $ 10.80 Stock-based Compensation Expense For the three and six months ended September 30, 2023 and 2022, stock-based compensation expense under the Company’s equity incentive plans was as follows (in thousands): Three Months Ended Six Months Ended 2023 2022 2023 2022 Research and development expenses $ 5,182 $ 3,813 $ 10,060 $ 7,419 General and administrative expenses 5,319 4,238 11,094 8,187 Total stock-based compensation $ 10,501 $ 8,051 $ 21,154 $ 15,606 As of September 30, 2023, total unrecognized compensation expense related to nonvested stock options and RSUs was $50.7 million and $38.3 million, respectively, which is expected to be recognized over the remaining weighted-average service period of 2.75 years and 2.85 years, respectively. Stock-based Compensation Allocated to the Company by RSL In relation to the RSL common share awards and options issued by RSL to employees of Roivant and the Company, the Company did not have any stock-based compensation expense for the three and six months ended September 30, 2023 and recorded $0.1 million and $0.2 million of stock-based compensation expense for the three and six months ended September 30, 2022, respectively, in the accompanying unaudited condensed consolidated statements of operations. RSL RSUs The Company’s Chief Executive Officer was granted 73,155 RSUs of RSL in January 2021, which are vesting over a period of four years. For the three months ended September 30, 2023, stock-based compensation expense recorded by the Company related to these RSUs was de minimis. For the three months ended September 30, 2022, the Company recorded $0.1 million of stock-based compensation expense related to these RSUs. For the six months ended September 30, 2023 and 2022, the Company recorded $0.1 million and $0.2 million, respectively, of stock-based compensation expense related to these RSUs. As of September 30, 2023, there was $0.1

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Litigation The Company is involved in various lawsuits, claims and other legal matters from time to time that arise in the ordinary course of conducting business. The Company records a liability when a particular contingency is probable and estimable. In February 2021, a putative securities class action complaint was filed against the Company and certain of its current and former officers in the U.S. District Court for the Eastern District of New York on behalf of a class consisting of those who acquired the Company’s securities between October 2, 2019 and February 1, 2021. The complaint alleges that the Company and certain of its officers violated Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, as amended, by making false and misleading statements regarding the safety of batoclimab and seeks unspecified monetary damages on behalf of the putative class and an award of costs and expenses, including reasonable attorneys’ fees. On December 29, 2021, the U.S. District Court appointed a lead plaintiff. On February 1, 2022, the lead plaintiff filed an amended complaint adding RSL and the Company’s directors and underwriters as defendants and asserting additional claims under Section 11, 12(a)(2), and 15 of the Securities Act of 1933 on behalf of a putative class consisting of those who purchased or otherwise acquired the Company’s securities pursuant and/or traceable to the Company’s follow-on public offering on or about September 2, 2020. On March 15, 2022, the lead plaintiff filed a further amended complaint. On February 14, 2023, the court granted the lead plaintiffs leave to amend. On March 17, 2023, the lead plaintiff filed a second amended complaint. The Company and other defendants served motions to dismiss the second amended complaint on April 28, 2023. The fully briefed motions to dismiss, including defendants’ opening briefs, lead plaintiff’s opposition, and defendants’ replies were filed with the court on June 30, 2023. No hearing date has been set. The Company intends to continue to vigorously defend the case and has not recorded a liability related to this lawsuit because, at this time, the Company is unable to reasonably estimate possible losses or determine whether an unfavorable outcome is either probable or remote. Commitments During the year ended March 31, 2022, ISG entered into the PSA with Samsung to manufacture a certain quantity of batoclimab drug substance for, among other things, commercial sale, if approved. As of September 30, 2023, in connection with this agreement, the Company has a remaining minimum obligation to Samsung of approximately $18.7 million, of which $3.5 million, $2.5 million and $12.7 million is expected to be paid during the remainder of the fiscal year ending March 31, 2024, and for the fiscal years ending March 31, 2025 and 2026, respectively. During the three and six months ended September 30, 2023, the Company recorded $0.6 million and $1.3 million, respectively, of research and development expenses related to the PSA and during the three and six months ended September 30, 2022, the Company recorded $1.7 million of research and development expenses related to the PSA. The Company made cash payments of $14.6 million related to the PSA during the six months ended September 30, 2023. Of the amount expected to be paid during the remainder of the fiscal year ending March 31, 2024, $3.2 million was included in accrued expenses in the accompanying unaudited condensed consolidated balance sheet as of September 30, 2023. See Note 3 - Material Agreements for additional details. As of September 30, 2023, the Company did not have any other ongoing material contractual obligations for which cash flows were fixed and determinable. In the normal course of business, the Company enters into agreements with CROs for clinical trials and with vendors for nonclinical studies, manufacturing and other services and products for operating purposes, which agreements are generally cancellable by the Company at any time, subject to payment of remaining obligations under binding purchase orders and, in certain cases, nominal early-termination fees. These commitments are not deemed significant. There are certain contracts wherein the Company has a minimum purchase commitment, however, most of it is due and payable within one year. Contingencies The extent of the impact of the post-COVID-19 environment, geopolitical tensions and global slowdown of economic activity, changes in inflation, rising interest rates and a potential recession in the U.S. on the Company’s future operational and financial performance will depend on certain developments, including the potential impact on our clinical trial plans and timelines, such as the enrollment, activation and initiation of additional clinical trial sites, and the results of our clinical trials, all of which are uncertain and cannot be predicted. At this point, the extent to which these events may impact the Company’s future financial condition or results of operations is uncertain.

Subsequent Event

Subsequent Event	6 Months Ended
	Sep. 30, 2023
Subsequent Events [Abstract]
Subsequent Event	Note 10 — Subsequent EventsIn October 2023, the Company completed an underwritten public offering of 8,475,500 shares of its common stock (including 1,526,316 shares of common stock purchased by RSL on the same terms as other investors in the offering and the full exercise of the underwriters’ option to purchase 1,105,500 additional shares of common stock) at a price to the public of $38.00 per share. Concurrent with the public offering, RSL purchased 4,473,684 shares of the Company’s common stock in a private placement exempt from the registration requirements of the Securities Act of 1933, as amended, at the same price per share as investors in the public offering of $38.00 per share. The net proceeds to the Company were approximately $466.6 million after deducting underwriting discounts and commissions, placement agent fees and offering expenses.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation	[A] Basis of Presentation The Company’s fiscal year ends on March 31 and its first three fiscal quarters end on June 30, September 30, and December 31, respectively. The accompanying condensed consolidated financial statements are unaudited. The unaudited condensed consolidated financial statements of the Company have been prepared in accordance with generally accepted accounting principles in the United States (“U.S. GAAP”) and follow the requirements of the Securities and Exchange Commission (“SEC”) for interim financial reporting. Accordingly, they do not include all of the information and disclosures required by U.S. GAAP for complete financial statements as certain footnotes or other financial information that are normally required by U.S. GAAP can be condensed or omitted. The unaudited condensed consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements. The unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. The Company has no unconsolidated subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. Certain amounts in the consolidated financial statements of the prior year have been reclassified to conform to current year presentation. Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”). In the opinion of management, the unaudited condensed consolidated financial statements include all normal and recurring adjustments that are considered necessary for the fair statement of results for the interim periods. The results for the three and six months ended September 30, 2023 are not necessarily indicative of those expected for the year ending March 31, 2024 or for any future period. The condensed consolidated balance sheet as of March 31, 2023 included herein was derived from the audited consolidated financial statements as of that date. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements included in the Company’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission (“SEC”) on May 22, 2023.
Use of Estimates	[B] Use of Estimates The preparation of unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the unaudited condensed consolidated financial statements and accompanying notes. The Company regularly evaluates estimates and assumptions related to assets, liabilities, stock-based compensation, litigation accruals, clinical trial accruals, operating leases, research and development costs and income taxes. The Company bases its estimates and assumptions on historical experience and on various other factors that it believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ from those estimates. Additionally, the Company assessed the impact of the post-COVID-19 environment, geopolitical tensions and global slowdown of economic activity, changes in inflation, rising interest rates and a potential recession in the U.S. on its operations and financial results as of September 30, 2023 and through the issuance of these unaudited condensed consolidated financial statements. The Company’s analysis was informed by the facts and circumstances as they were known to the Company. This assessment considered the impact that these uncertainties may have on financial estimates and assumptions that affect the reported amounts of assets and liabilities and expenses.
Risks and Uncertainties	[C] Risks and Uncertainties The Company is subject to risks common to early-stage companies in the biopharmaceutical industry including, but not limited to, uncertainties related to clinical effectiveness of products, commercialization of products, regulatory approvals, dependence on key products, key personnel and third-party service providers such as contract research organizations (“CROs”), protection of intellectual property rights and the ability to make milestone, royalty or other payments due under any license, collaboration or supply agreements.
Concentration of Credit Risk	[D] Concentration of Credit Risk Financial instruments that potentially subject the Company to concentration of credit risk include cash and cash equivalents. As of September 30, 2023, the cash and cash equivalents balance is kept in banking institutions that the Company believes are of high credit quality and are in excess of federally insured levels. The Company maintains its cash and cash equivalents with accredited financial institutions and accordingly, such funds are subject to minimal credit risk. The Company has not experienced any losses on its cash and cash equivalents.
Cash and Cash Equivalents	[E] Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less from the date of purchase to be cash equivalents. As of September 30, 2023 and March 31, 2023, cash and cash equivalents included $254.1
Research and Development Expenses	[F] Research and Development Expenses Research and development costs with no alternative future use are expensed as incurred. Research and development expenses primarily consist of employee-related costs and expenses from third parties who conduct research and development activities (including manufacturing) on behalf of the Company. The Company accrues costs for clinical trial activities based upon estimates of the services received and related expenses incurred that have yet to be invoiced by CROs. In making these estimates, the Company considers various factors, including status and timing of services performed, the number of patients enrolled and the rate of patient enrollment. The Company accrues costs for non-clinical studies and contract manufacturing activities over the service periods specified in the contracts and are adjusted as necessary based upon an ongoing review of the level of effort and costs actually incurred. The estimate of the work completed is developed through discussions with internal personnel and external services providers as to the progress toward completion of the services and the agreed-upon fee to be paid for such services. As actual costs become known, the accrued estimates are adjusted. Such estimates are not expected to be materially different from amounts actually incurred.
Acquired In-Process Research and Development Expenses	[G] Acquired In-Process Research and Development Expenses Acquired in-process research and development (“IPR&D”) expenses include payments made or due in connection with license agreements upon the achievement of development and regulatory milestones. The Company evaluates in-licensed agreements for IPR&D projects to determine if it meets the definition of a business and thus should be accounted for as a business combination. If the in-licensed agreement for IPR&D does not meet the definition of a business and the assets have not reached technological feasibility and therefore have no alternative future use, the Company expenses payments made under such license agreements as acquired in-process research and development expenses in its unaudited condensed consolidated statements of operations. Payments for milestones achieved and payments for a product license prior to regulatory approval of the product are expensed in the period incurred. Payments made in connection with regulatory and sales-based milestones will be capitalized and amortized to cost of product sales over the remaining useful life of the asset.
Stock-based Compensation	[H] Stock-based Compensation Stock-based awards to employees and directors are valued at fair value on the date of the grant and that fair value is recognized as stock-based compensation expense over the requisite service period. The grant date fair value of the stock-based awards with graded vesting is recognized on a straight-line basis over the requisite service period, which is generally the vesting period of the respective awards. The Company values its stock options that only have service vesting requirements using the Black-Scholes option pricing model. Stock-based compensation related to restricted stock awards is based on the fair value of the Company’s common stock on the grant date. When determining the grant-date fair value of stock-based awards, management further considers whether an adjustment is required to the observable market price or volatility of the Company’s common stock that is used in the valuation as a result of material non-public information, if that information is expected to result in a material increase in share price. Certain assumptions need to be made with respect to utilizing the Black-Scholes option pricing model, including the expected life of the award, volatility of the underlying shares, the risk-free interest rate, expected dividend yield and the fair value of the Company’s common stock. Since the Company has limited option exercise history, it has generally elected to estimate the expected life of an award based upon the “simplified method” with the continued use of this method extended until such time the Company has sufficient exercise history. The expected share price volatility for the Company’s common stock is estimated by taking the average historical price volatility for the Company’s peers. The risk-free interest rate is based on the rates paid on securities issued by the U.S. Treasury with a term approximating the expected life of the equity award. As the Company has never paid and does not anticipate paying cash dividends on its common stock, the expected dividend yield is assumed to be zero. The Company accounts for pre-vesting award forfeitures when they occur.
Net Loss per Common Share	[I] Net Loss per Common Share Basic net loss per common share is computed by dividing net loss applicable to common stockholders by the weighted-average number of common stock outstanding during the period. Diluted net loss per common share is computed by dividing the net loss applicable to common stockholders by the diluted weighted-average number of common stock outstanding during the period. In periods in which the Company reports a net loss, all common stock equivalents are deemed anti-dilutive such that basic net loss per common share and diluted net loss per common share are equivalent. Potentially dilutive common stock has been excluded from the diluted net loss per common share computations in all periods presented because such securities have an anti-dilutive effect on net loss per common share due to the Company’s net loss. There are no reconciling items used to calculate the weighted-average number of total common stock outstanding for basic and diluted net loss per common share data.
Recent Accounting Pronouncements	[J] Recent Accounting Pronouncements Recent authoritative guidance issued by the FASB (including technical corrections to the ASC), the American Institute of Certified Public Accountants, and the SEC did not, or are not expected to, have a material impact on the Company’s unaudited condensed consolidated financial statements and related disclosures.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Summary of Potentially Dilutive Securities that Have Been Excluded from the Calculation of Diluted Net Loss Per Share Due to their Anti-Dilutive Effect	The following potentially dilutive securities have been excluded from the calculation of diluted net loss per share due to their anti-dilutive effect: Six Months Ended September 30, 2023 2022 Preferred stock as converted 10,000 10,000 Stock Options 13,372,356 11,185,963 Restricted stock units 4,036,663 4,587,727 Total 17,419,019 15,783,690

Accrued Expenses (Tables)

Accrued Expenses (Tables)	6 Months Ended
	Sep. 30, 2023
Payables and Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses consist of the following (in thousands): September 30, 2023 March 31, 2023 Research and development expenses $ 24,819 $ 31,321 Accrued bonuses 4,850 7,530 Legal and other professional fees 819 572 Other expenses 1,646 1,348 Total accrued expenses $ 32,134 $ 40,771

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	6 Months Ended
	Sep. 30, 2023
Equity [Abstract]
Schedule of Common Stock Reserved for Future Issuance	The Company has reserved the following shares of common stock for issuance: September 30, 2023 March 31, 2023 Conversion of Series A preferred stock 10,000 10,000 Stock options outstanding 13,572,050 11,682,481 Restricted stock units outstanding 4,613,965 4,057,778 Equity awards available for future grants 2,245,595 590,317 Total 20,441,610 16,340,576

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Summary of Stock Option Activity	A summary of the stock option activity under the Company’s equity incentive plans is as follows: Number of Stock Weighted- Remaining Aggregate Balance - March 31, 2023 11,682,481 $ 8.05 8.16 $ 88,919 Granted 2,080,263 15.13 Exercised (340,329) 7.98 Forfeited (46,432) 9.85 Expired (3,627) 8.62 Balance - September 30, 2023 13,372,356 $ 9.14 7.99 $ 391,077 Exercisable - September 30, 2023 6,648,722 $ 8.14 7.09 $ 201,142
Schedule of Fair Value Assumptions	The Company estimated the fair value of each option on the date of grant using the Black-Scholes option pricing model applying the weighted-average assumptions in the following table: Three Months Ended September 30, Six Months Ended September 30, 2023 2022 2023 2022 Risk-free interest rate 4.10% - 4.62% 2.89% - 4.11% 3.45% - 4.62% 2.74% - 4.11% Expected term, in years 6.11 6.11 6.11 6.11 Expected volatility 97.68% - 97.81% 88.53% - 88.78% 93.66% - 98.15% 87.12% - 88.78% Expected dividend yield —% —% —% —%
Schedule of Restricted Stock Unit Awards Activity	A summary of RSUs activity under the Company’s equity incentive plans is as follows: Number of RSUs Weighted- Average Grant Date Fair Value Nonvested as of March 31, 2023 3,692,979 $ 7.63 Issued 1,559,349 15.08 Vested (1,184,029) 6.55 Forfeited (31,636) 9.96 Nonvested as of September 30, 2023 4,036,663 $ 10.80
Summary of Stock-based Compensation Expense	For the three and six months ended September 30, 2023 and 2022, stock-based compensation expense under the Company’s equity incentive plans was as follows (in thousands): Three Months Ended Six Months Ended 2023 2022 2023 2022 Research and development expenses $ 5,182 $ 3,813 $ 10,060 $ 7,419 General and administrative expenses 5,319 4,238 11,094 8,187 Total stock-based compensation $ 10,501 $ 8,051 $ 21,154 $ 15,606

Description of Business and L_2

Description of Business and Liquidity - Additional Information (Detail) $ in Thousands	6 Months Ended
	Sep. 30, 2023 USD ($) segment	Mar. 31, 2023 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of reportable segments | segment	1
Number of operating segments | segment	1
Cash and cash equivalents | $	$ 269,928	$ 376,532
Accumulated deficit | $	$ 698,946	$ 566,347

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Mar. 31, 2023
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 269,928		$ 269,928		$ 376,532
Expected dividend yield	0%	0%	0%	0%
Money Market Funds | Fair Value, Inputs, Level 1
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 254,100		$ 254,100		$ 346,200

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of potentially dilutive securities have been excluded from the calculation of diluted net loss per share due to their anti-dilutive effect (Detail) - shares	6 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	17,419,019	15,783,690
Preferred stock as converted
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	10,000	10,000
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	13,372,356	11,185,963
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	4,036,663	4,587,727

Material Agreements - Additiona

Material Agreements - Additional Information (Detail) - USD ($)				6 Months Ended
	Nov. 17, 2021	Dec. 07, 2018	Dec. 19, 2017	Sep. 30, 2023	Mar. 31, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront, non-refundable payment			$ 30,000,000
Research and development and out-of-pocket (in percent)			50%
Cumulative milestone payments				$ 32,500,000
Purchase price		$ 37,800,000
Acquired in-process research and development				12,500,000
HanAll Biopharma Co., Ltd
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development payable				0	$ 0
Samsung Biologics Co., Ltd
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Purchase obligation, additional purchases, period (in years)	4 years
Purchase obligation, termination notice period (in days)	30 days
Purchase obligation, fees covered, termination period (in years)	2 years
Purchase obligation				$ 18,700,000
Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Consideration paid			$ 20,000,000
Maximum | Upon Achievement Of Development Regulatory And Sales Milestones
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contingent milestone payments			$ 420,000,000

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2023	Mar. 31, 2023
Payables and Accruals [Abstract]
Research and development expenses	$ 24,819	$ 31,321
Accrued bonuses	4,850	7,530
Legal and other professional fees	819	572
Other expenses	1,646	1,348
Total accrued expenses	$ 32,134	$ 40,771

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) $ in Millions	1 Months Ended		3 Months Ended		6 Months Ended
	Oct. 31, 2023 shares	Aug. 31, 2018	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Jun. 30, 2020 subleaseAgreement
Related Party Transaction [Line Items]
Number of sublease agreements | subleaseAgreement							2
Operating lease rent expense | $			$ 0.3	$ 0.3	$ 0.6	$ 0.6
Public Stock Offering | Subsequent Event
Related Party Transaction [Line Items]
Number of shares issued in transaction (in shares)	8,475,500
Private Placement | Subsequent Event
Related Party Transaction [Line Items]
Number of shares issued in transaction (in shares)	4,473,684
Related Party
Related Party Transaction [Line Items]
Purchase obligation, termination notice period (in days)		90 days
Related Party | Public Stock Offering | Subsequent Event
Related Party Transaction [Line Items]
Number of shares issued in transaction (in shares)	1,526,316

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Effective income tax rate (in percent)	(0.78%)	(0.55%)	(0.34%)	(0.70%)

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - $ / shares	6 Months Ended
	Sep. 30, 2023	Mar. 31, 2023
Subsidiary or Equity Method Investee [Line Items]
Preferred stock, par value (in dollars per share)	$ 0.0001
Common stock, authorized (in shares)	500,000,000	500,000,000
Common stock, issued (in shares)	131,442,024	130,329,863
Common stock, outstanding (in shares)	131,442,024	130,329,863
Equity Inducement Plan 2023
Subsidiary or Equity Method Investee [Line Items]
Number of shares issued in transaction (in shares)	5,000,000
Stock Options Not Settled
Subsidiary or Equity Method Investee [Line Items]
Units outstanding (in shares)	199,694
Restricted Stock Units Vested And Not Settled (Not Unvested)
Subsidiary or Equity Method Investee [Line Items]
Units outstanding (in shares)	577,302
Series A  preferred stock
Subsidiary or Equity Method Investee [Line Items]
Preferred stock, issued (in shares)	10,000	10,000
Preferred stock, outstanding (in shares)	10,000	10,000
Share of common stock (in shares)	1
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Liquidation amount per share (in dollars per share)	$ 0.01
Preferred stock, authorized (in shares)	10,000	10,000
Series A  preferred stock | Maximum
Subsidiary or Equity Method Investee [Line Items]
Percentage of voting power of outstanding shares	25%
Roivant Sciences Ltd. | Series A  preferred stock
Subsidiary or Equity Method Investee [Line Items]
Preferred stock, issued (in shares)	10,000
Preferred stock, outstanding (in shares)	10,000
Preferred stock, par value (in dollars per share)	$ 0.0001
Preferred Stock
Subsidiary or Equity Method Investee [Line Items]
Preferred stock, issued (in shares)	0
Preferred stock, outstanding (in shares)	0
Preferred stock, authorized (in shares)	10,010,000
Common stock
Subsidiary or Equity Method Investee [Line Items]
Common stock, authorized (in shares)	500,000,000
Common stock, par value (in dollars per share)	$ 0.0001
Common stock, issued (in shares)	131,442,024
Common stock, outstanding (in shares)	131,442,024

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of common stock reserved for future issuance (Detail) - shares	Sep. 30, 2023	Apr. 01, 2023	Mar. 31, 2023
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Conversion of Series A preferred stock (in shares)	10,000		10,000
Stock options outstanding (in shares)	13,372,356		11,682,481
Equity awards available for future grants (in shares)	2,245,595		590,317
Total (in shares)	20,441,610	5,213,194	16,340,576
Restricted stock units outstanding
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Units outstanding (in shares)	4,613,965		4,057,778
Stock Options And Stock Options Not Vested
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Stock options outstanding (in shares)	13,572,050		11,682,481

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	Jan. 31, 2021	Dec. 31, 2019	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Apr. 01, 2023	Mar. 31, 2023	Feb. 01, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares available for future issuance (in shares)			20,441,610		20,441,610		5,213,194	16,340,576
Common shares outstanding (in shares)			2,245,595		2,245,595			590,317
Number of options, granted (in shares)					2,080,263
Share based compensation expense			$ 10,501	$ 8,051	$ 21,154	$ 15,606
Related Party
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation expense			$ 0	100	$ 0	200
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units outstanding (in shares)			4,036,663		4,036,663			3,692,979
Unrecognized equity-based compensation related to unvested stock options and RSUs			$ 38,300		$ 38,300
Remaining weighted average service period for recognition					2 years 10 months 6 days
Restricted stock units, grants in period (in shares)					1,559,349
Restricted stock units | Related Party
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized equity-based compensation related to unvested stock options and RSUs			100		$ 100
Share based compensation expense				$ 100	100	$ 200
Restricted stock units, grants in period (in shares)	73,155
Award vesting period	4 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized equity-based compensation related to unvested stock options and RSUs			$ 50,700		$ 50,700
Remaining weighted average service period for recognition					2 years 9 months
2019 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares available for future issuance (in shares)		5,500,000	2,245,595		2,245,595
Maximum number of shares issued (in shares)		16,500,000
Percentage of common stock outstanding		4%
Common shares outstanding (in shares)			10,747,935		10,747,935
2019 Equity Incentive Plan | Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units outstanding (in shares)			4,036,663		4,036,663
2018 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares outstanding (in shares)			2,624,421		2,624,421
Inducement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares available for future issuance (in shares)									5,000,000
Number of options, granted (in shares)					0

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of stock option activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Sep. 30, 2023	Mar. 31, 2023
Number of Stock Options
Number of options, beginning balance (in shares)	11,682,481
Number of options, granted (in shares)	2,080,263
Number of options, exercised (in shares)	(340,329)
Number of options, forfeited (in shares)	(46,432)
Number of options, expired (in shares)	(3,627)
Number of options, ending balance (in shares)	13,372,356	11,682,481
Weighted- Average Exercise Price
Weighted-average exercise price, beginning balance (in dollars per share)	$ 8.05
Weighted-average exercise price, granted (in dollars per share)	15.13
Weighted average exercise price, exercised (in dollars per share)	7.98
Weighted-average exercise price, forfeited (in dollars per share)	9.85
Weighted-average exercise price, expired (in dollars per share)	8.62
Weighted-average exercise price, ending balance (in dollars per share)	$ 9.14	$ 8.05
Additional Disclosures
Remaining contractual term	7 years 11 months 26 days	8 years 1 month 28 days
Aggregate intrinsic value	$ 391,077	$ 88,919
Number of options, exercisable (in shares)	6,648,722
Weighted-average exercise price, exercisable (in dollars per share)	$ 8.14
Remaining contractual term, exercisable	7 years 1 month 2 days
Aggregate intrinsic value, exercisable	$ 201,142

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of fair value assumptions (Detail)	3 Months Ended		6 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term, in years	6 years 1 month 9 days	6 years 1 month 9 days	6 years 1 month 9 days	6 years 1 month 9 days
Expected dividend yield	0%	0%	0%	0%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	4.10%	2.89%	3.45%	2.74%
Expected volatility	97.68%	88.53%	93.66%	87.12%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	4.62%	4.11%	4.62%	4.11%
Expected volatility	97.81%	88.78%	98.15%	88.78%

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Restricted Stock Unit Awards (Details) - Restricted stock units	6 Months Ended
	Sep. 30, 2023 $ / shares shares
Number of RSUs
Outstanding, beginning balance (in shares) | shares	3,692,979
Restricted stock units, issued (in shares) | shares	1,559,349
Restricted stock units, vested (in shares) | shares	(1,184,029)
Restricted stock units, forfeited (in shares) | shares	(31,636)
Outstanding, ending balance (in shares) | shares	4,036,663
Weighted- Average Grant Date Fair Value
Outstanding, weighted-average grant date fair value, beginning balance (in dollars per share) | $ / shares	$ 7.63
Issued, weighted-average grant date fair value (in dollars per share) | $ / shares	15.08
Vested, weighted-average grant date fair value (in dollars per share) | $ / shares	6.55
Forfeited, weighted-average grant date fair value (in dollars per share) | $ / shares	9.96
Outstanding, weighted-average grant date fair value, ending balance (in dollars per share) | $ / shares	$ 10.80

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of share based compensation expense (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 10,501	$ 8,051	$ 21,154	$ 15,606
Research and development expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	5,182	3,813	10,060	7,419
General and administrative expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 5,319	$ 4,238	$ 11,094	$ 8,187

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) - Samsung Biologics Co., Ltd - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Long-term Purchase Commitment [Line Items]
Purchase obligation	$ 18.7		$ 18.7
Purchase obligation, to be paid in 2023	3.5		3.5
Purchase Obligation, to be paid in 2024	2.5		2.5
Purchase obligation, to be paid in 2026	12.7		12.7
Research and development	0.6	$ 1.7	1.3	$ 1.7
Payments for purchase commitments			14.6
Accrued Expenses
Long-term Purchase Commitment [Line Items]
Purchase obligation, to be paid in 2023	$ 3.2		$ 3.2

Subsequent Event (Details)

Subsequent Event (Details) - Subsequent Event $ / shares in Units, $ in Millions	1 Months Ended
	Oct. 31, 2023 USD ($) $ / shares shares
Subsequent Event [Line Items]
Public share price (in dollars per share) | $ / shares	$ 38
Public Stock Offering
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares)	8,475,500
Consideration received from sale of stock | $	$ 466.6
Over-Allotment Option
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares)	1,105,500
Private Placement
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares)	4,473,684
Related Party | Public Stock Offering
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares)	1,526,316