Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Mar. 31, 2019	May 21, 2019	Sep. 30, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	Myovant Sciences Ltd.
Entity Central Index Key	0001679082
Document Type	10-K
Document Period End Date	Mar. 31, 2019
Amendment Flag	false
Current Fiscal Year End Date	--03-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		72,198,383
Entity Small Business	false
Entity Emerging Growth Company	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Entity Public Float			$ 755.2
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Shell Company	false

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2019	Mar. 31, 2018
Current assets:
Cash and cash equivalents	$ 156,074	$ 108,624
Prepaid expenses and other current assets	10,194	5,139
Income tax receivable	524	1,000
Total current assets	166,792	114,763
Property and equipment, net	2,071	1,273
Other assets	4,114	3,065
Total assets	172,977	119,101
Current liabilities:
Accounts payable	11,019	4,578
Interest payable	1,077	282
Accrued expenses	53,614	30,265
Due to RSL, RSI and RSG	121	1,960
Current maturities of long-term debt	6,142	0
Total current liabilities	71,973	37,085
Deferred rent	1,157	408
Deferred interest payable	2,273	255
Long-term debt, less current maturities	93,240	43,624
Total liabilities	168,643	81,372
Commitments and contingencies (Note 11)
Shareholders’ equity:
Common shares, par value $0.000017727 per share, 564,111,242 shares authorized,72,057,490 and 60,997,856 issued and outstanding at March 31, 2019 and 2018, respectively	1	1
Additional paid-in capital	505,851	266,178
Accumulated other comprehensive income	507	24
Accumulated deficit	(502,025)	(228,474)
Total shareholders’ equity	4,334	37,729
Total liabilities and shareholders’ equity	$ 172,977	$ 119,101

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2019	Mar. 31, 2018
Statement of Financial Position [Abstract]
Common shares par value (in USD per share)	$ 0.000017727	$ 0.000017727
Common shares authorized (in shares)	564,111,242	564,111,242
Common shares issued (in shares)	72,057,490	60,997,856
Common shares outstanding (in shares)	72,057,490	60,997,856

Consolidated Statements of Operations - USD ($)
$ in Thousands

12 Months Ended

Mar. 31, 2019

Mar. 31, 2018

Mar. 31, 2017

Operating expenses:

Research and development

^[1]

$ 222,607

$ 116,832

$ 43,500

General and administrative

^[2]

42,219

24,231

12,357

Total operating expenses

264,826

141,063

55,857

Changes in the fair value of the Takeda warrant liability

27,518

Interest expense

8,821

2,046

Interest income

(881)

Other expense (income), net

309

(67)

139

Loss before income taxes

(273,075)

(143,042)

(83,514)

Income tax expense (benefit)

476

213

(74)

Net loss

$ (273,551)

$ (143,255)

$ (83,440)

Net loss per common share — basic and diluted (in USD per share)

$ (4.09)

$ (2.41)

$ (1.70)

Weighted average common shares outstanding — basic and diluted (in shares)

66,910,060

59,520,747

49,184,668

[1]	Includes $2,575, $4,537 and $9,669 of costs allocated from RSL, RSI, and RSG during the years ended March 31, 2019, 2018 and 2017, respectively. Also includes share-based compensation expense (see Note 9).
[2]	Includes $2,873, $4,182 and $4,409 of costs allocated from RSL, RSI, and RSG during the years ended March 31, 2019, 2018 and 2017, respectively. Also includes share-based compensation expense (see Note 9).

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (273,551)	$ (143,255)	$ (83,440)
Other comprehensive income (loss):
Foreign currency translation adjustment	483	(116)	140
Total other comprehensive income (loss)	483	(116)	140
Comprehensive loss	$ (273,068)	$ (143,371)	$ (83,300)

- Definition

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

+ References + Details

Consolidated Statements of Shareholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Shares	Common Shares Subscribed	Additional Paid in Capital	Accumulated Other Comprehensive Income	Accumulated Deficit	Initial Public Offering	Initial Public Offering Common Shares	Initial Public Offering Additional Paid in Capital	Private Placement Cowen and Company, LLC	Private Placement Cowen and Company, LLC Common Shares	Private Placement Cowen and Company, LLC Additional Paid in Capital	Private Placement Roivant Sciences, Ltd.	Private Placement Roivant Sciences, Ltd. Common Shares	Private Placement Roivant Sciences, Ltd. Additional Paid in Capital	Private Placement NovaQuest	Private Placement NovaQuest Common Shares	Private Placement NovaQuest Additional Paid in Capital	Public Equity Offering	Public Equity Offering Common Shares	Public Equity Offering Additional Paid in Capital
Beginning balance (in shares) at Mar. 31, 2016		37,231,342
Beginning balance at Mar. 31, 2016	$ (223)	$ 1	$ (1)	$ 1,434	$ 0	$ (1,657)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)								14,500,000
Shares issued							$ 199,964	$ 0	$ 199,964
Shares issued to Takeda under the Takeda license agreement (in shares)		5,077,001
Shares issued to Takeda under the Takeda license agreement	$ 7,740	$ 0		7,740
Shares issued to settle the Takeda warrant liability (in shares)	2,339,192	2,339,192					1,977,269
Shares issued to settle the Takeda warrant liability	$ 32,843	$ 0		32,843
Share-based compensation expense (in shares)		1,128,222
Share-based compensation expense	3,775	$ 0		3,775
Capital contribution — share-based compensation	4,942			4,942
Capital contribution	1,035			1,035
Foreign currency translation adjustment	140				140
Net loss	(83,440)					(83,440)
Ending balance (in shares) at Mar. 31, 2017		60,275,757
Ending balance at Mar. 31, 2017	166,776	$ 1	(1)	251,733	140	(85,097)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)		138,361
Shares issued	$ 1,857	$ 0		1,857
Shares issued to settle the Takeda warrant liability (in shares)	4,432	4,432
Shares issued to settle the Takeda warrant liability	$ 58	$ 0		58
Share-based compensation expense (in shares)		564,111
Share-based compensation expense	10,587	$ 0		10,587
Capital contribution — share-based compensation	996			996
Foreign currency translation adjustment	$ (116)				(116)
Stock option exercises (in shares)	15,195	15,195
Stock option exercises	$ 36	$ 0		36
Warrants issued with debt financing	789			789
Settlement of RSL common shares subscribed	1		1
Net loss	$ (143,255)					(143,255)
Ending balance (in shares) at Mar. 31, 2018	60,997,856	60,997,856
Ending balance at Mar. 31, 2018	$ 37,729	$ 1	0	266,178	24	(228,474)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)											3,970,129			1,110,015			2,286,284			3,533,399
Shares issued										$ 84,052	$ 0	$ 84,052	$ 22,500	$ 0	$ 22,500	$ 37,982	$ 0	$ 37,982	$ 74,391	$ 0	$ 74,391
Share-based compensation expense (in shares)		0
Share-based compensation expense	18,067	$ 0		18,067
Capital contribution — share-based compensation	629			629
Capital contribution	752			752
Foreign currency translation adjustment	$ 483				483
Stock option exercises (in shares)	154,494
Issuance of shares upon exercise of stock options and vesting of RSUs (in shares)		159,807
Issuance of shares upon exercise of stock options and vesting of RSUs	$ 1,300			1,300
Net loss	$ (273,551)					(273,551)
Ending balance (in shares) at Mar. 31, 2019	72,057,490	72,057,490
Ending balance at Mar. 31, 2019	$ 4,334	$ 1	$ 0	$ 505,851	$ 507	$ (502,025)

Consolidated Statements of Shareholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Initial Public Offering
Issuance costs			$ 17,536
Public Equity Offering
Issuance costs	$ 5,110
NovaQuest \| Private Placement
Issuance costs		$ 624
Cowen and Company, LLC \| Private Placement
Issuance costs	$ 2,919

Consolidated Statement of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net loss	$ (273,551)	$ (143,255)	$ (83,440)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation	18,696	11,583	8,717
Depreciation	438	243	61
Amortization of debt discount and issuance costs	2,084	662	0
Acquisition of in-process research and development	0	0	13,117
Changes in the fair value of the Takeda warrant liability	0	0	27,518
Others	1,235	(116)	140
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(5,055)	(1,918)	(3,221)
Deferred tax assets	0	208	(208)
Income tax receivable	476	(895)	(105)
Other assets	76	(3,065)	0
Accounts payable	6,441	1,249	3,329
Interest payable	795	282	0
Accrued expenses	23,349	18,287	11,755
Due to RSL, RSI and RSG	(1,839)	(1,070)	4,009
Deferred rent	749	295	113
Deferred interest payable	2,018	255	0
Net cash used in operating activities	(224,088)	(117,255)	(18,215)
Cash flows from investing activities:
Purchase of property and equipment	(1,236)	(604)	(967)
Net cash used in investing activities	(1,236)	(604)	(967)
Cash flows from financing activities:
Cash proceeds from issuance of common shares in initial public offering, net of underwriting discount	0	0	202,275
Initial public offering costs paid	0	0	(2,311)
Cash proceeds from issuance of common shares, net of issuance costs paid	37,982	1,857	0
Cash proceeds from debt financings, net of financing costs paid	53,974	43,751	0
Cash capital contribution from RSL	0	0	1,035
Settlement of RSL common shares subscribed	0	1	0
Cash proceeds from stock option exercises	1,300	36	0
Cash paid to NovaQuest for annual debt administration fee	(300)	0	0
Due to RSL and RSI for amounts paid on behalf of the Company	0	0	(979)
Net cash provided by financing activities	273,899	45,645	200,020
Net change in cash, cash equivalents and restricted cash	48,575	(72,214)	180,838
Cash, cash equivalents and restricted cash, beginning of period	108,624	180,838	0
Cash, cash equivalents and restricted cash, end of period	157,199	108,624	180,838
Non-cash investing and financing activities:
Acquisition of in-process research and development	0	0	13,117
Warrants issued to Hercules	0	789	0
Supplemental disclosure of cash paid:
Income taxes	0	900	240
Interest	3,923	845	0
Public Equity Offering
Cash flows from financing activities:
Cash proceeds from issuance of common shares, net of issuance costs paid	74,391	0	0
Cowen and Company, LLC \| Private Placement
Cash flows from financing activities:
Cash proceeds from issuance of common shares, net of issuance costs paid	84,052	0	0
Roivant Sciences, Ltd. \| Private Placement
Cash flows from financing activities:
Cash proceeds from issuance of common shares, net of issuance costs paid	$ 22,500	$ 0	$ 0

Description of Business	12 Months Ended
Description of Business	Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business Myovant Sciences Ltd. (or together with its wholly owned subsidiaries, the Company) is a clinical-stage healthcare company focused on developing and commercializing innovative therapies for women’s health and prostate cancer. The Company is developing relugolix 40 mg in combination with low-dose estradiol and a progestin for the treatment of heavy menstrual bleeding associated with uterine fibroids and for pain associated with endometriosis, relugolix 120 mg as a monotherapy for advanced prostate cancer, and an additional product candidate, MVT-602, an oligopeptide kisspeptin-1 receptor agonist, for the treatment of female infertility as part of assisted reproduction. Both relugolix and MVT-602 were licensed to the Company by Takeda Pharmaceuticals International AG, or Takeda, on April 29, 2016. The Company is an exempted company limited by shares incorporated under the laws of Bermuda in February 2016 under the name Roivant Endocrinology Ltd. The Company changed its name to Myovant Sciences Ltd. in May 2016. Since its inception, the Company has devoted substantially all of its efforts to identifying and in-licensing its product candidates, organizing and staffing the Company, raising capital, preparing for and advancing the clinical development of its product candidates, and preparing for potential future regulatory approvals and commercialization of relugolix. The Company has incurred, and expects to continue to incur, significant operating losses and negative cash flows as it continues to develop its product candidates and prepares for potential future regulatory approvals and commercialization of relugolix. To date, the Company has not generated any revenue, and it does not expect to generate revenue unless and until it successfully completes development and obtains regulatory approval for at least one of its product candidates. See Note 2(C), “Summary of Significant Accounting Policies—Going Concern and Management’s Plans.” On May 14, 2019, the Company announced that LIBERTY 1, the first of two Phase 3 studies of once daily relugolix combination therapy in women with uterine fibroids and heavy menstrual bleeding, met its primary efficacy endpoint and six key secondary endpoints. The Company further expects to announce top-line results from four additional Phase 3 clinical trials over the next three quarters.

Summary of Significant Accounting Policies

12 Months Ended

Mar. 31, 2019

Accounting Policies [Abstract]

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. The Company has determined that it has one operating and reporting segment as it allocates resources and assesses financial performance on a consolidated basis.

The accompanying consolidated financial statements have been prepared in accordance with United States, or U.S., generally accepted accounting principles, or U.S. GAAP.

Any reference in these notes to applicable accounting guidance is meant to refer to the authoritative U.S. GAAP included in the Accounting Standards Codification, or ASC, and Accounting Standards Update, or ASU, issued by the Financial Accounting Standards Board, or FASB. The 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.

(B) Use of Estimates:

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions in certain circumstances that affect the amounts reported in the consolidated financial statements and accompanying notes. The Company regularly evaluates estimates and assumptions related to assets, liabilities, costs, and expenses, including the evaluation of the Company’s ability to continue as a going concern, compensation and other expenses allocated to the Company under its services agreements with Roivant Sciences, Inc., or RSI, and Roivant Sciences GmbH, or RSG, each a wholly owned subsidiary of the Company’s controlling shareholder, Roivant Sciences Ltd., or RSL, as well as share-based compensation expenses, research and development, or R&D, expenses and accruals, 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 at the date of the consolidated financial statements and the reported amounts of expenses incurred during the reporting period, that are not readily apparent from other sources. Actual results could differ from those estimates.

The Company has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date the consolidated financial statements are issued. During the year ended March 31, 2019, the Company incurred net losses of $273.6 million and used $224.1 million of cash and cash equivalents in operations. The Company expects to continue to incur significant and increasing operating losses and negative cash flows as it continues to develop its product candidates and prepares for potential future regulatory approvals and commercialization of relugolix. The Company has not generated any revenue to date and does not expect to generate product revenue unless and until it successfully completes development and obtains regulatory approval for at least one of its product candidates. Based on its current operating plan, the Company expects that its existing cash and cash equivalents will be sufficient to fund its operating expenses and capital expenditure requirements through at least the first quarter of its fiscal year ending March 31, 2020. This estimate is based on the Company’s current assumptions, including assumptions relating to its ability to manage its spend, that might prove to be wrong, and it could use its available capital resources sooner than it currently expects. These funds will not be sufficient to enable the Company to complete all necessary development activities and commercially launch relugolix. The Company anticipates that it will continue to incur net losses for the foreseeable future.

To continue as a going concern, the Company will need, among other things, additional capital resources. The Company continually assesses multiple options to obtain additional funding to support its operations, including through financing activities in public or private capital markets, financing arrangements with Roivant Sciences, structured transactions such as royalty financings, collaborations, license or development agreements, or other collaborations and cost containment measures. Management can provide no assurances that any sources of a sufficient amount of financing will be available to the Company on favorable terms, if at all. Although the Company believes that it will continue to raise capital to fund its operations as it has in the past, ASC 240-40, Going Concern, does not allow the Company to consider future financing activities that are not probable of being implemented in its assessment of the Company’s future cash burn for the purpose of its liquidity assessment.

Due to these uncertainties, there is substantial doubt about the Company’s ability to continue as a going concern. The consolidated financial statements and footnotes have been prepared on the basis that the Company will continue as a going concern, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classification of liabilities that may result from the possible inability of the Company to continue as a going concern.

(D) Risks and Uncertainties:

The Company is subject to risks common to companies in the biotechnology industry, including, but not limited to, risks of failure or unsatisfactory results of nonclinical studies and clinical trials, the need to obtain additional financing to fund the future development of its product candidates, the need to obtain marketing approval for its product candidates, the need to successfully commercialize and gain market acceptance of its product candidates, dependence on key personnel, protection of proprietary technology, compliance with government regulations, development by competitors of technological innovations, ability to transition from pilot-scale manufacturing to large-scale production of products, and dependence on third-party service providers such as contract research organizations, or CROs, and contract manufacturing organizations, or CMOs.

(E) Concentrations of Credit Risk:

Financial instruments that potentially subject the Company to concentrations of credit risk include cash and cash equivalents consisting of money market funds and commercial paper. As of March 31, 2019, cash and cash equivalent balances are diversified between three financial institutions. The Company is exposed to credit risk in the event of default by the financial institutions holding its cash and the issuers of its money market funds and commercial paper. The Company maintains its cash deposits and cash equivalents in highly-rated, federally-insured financial institutions in excess of federally insured limits. The Company has established guidelines relative to diversification and maturities of investments to maintain safety and liquidity. The Company has not experienced any credit losses related to these financial instruments and does not believe that it is exposed to any significant credit risk related to these instruments.

(F) Cash, Cash Equivalents, and Restricted Cash:

Cash and cash equivalents include cash deposits in banks and all highly liquid investments that are readily convertible to cash. The Company considers all highly liquid investments with a maturity of three months or less at the time of purchase to be cash equivalents. Interest income consists of interest earned on money market funds and the accretion of discounts to maturity for commercial paper.

Restricted cash consists of non-interest bearing legally restricted deposits held as compensating balances against the Company’s corporate credit card program and an irrevocable standby letter of credit provided as security for the Company’s office lease. Cash as reported in the consolidated statements of cash flows includes the aggregate amounts of cash, cash equivalents, and restricted cash, and consists of the following (in thousands):



	March 31,
	2019		2018		2017
Cash and cash equivalents	$	156,074	$	108,624	$	180,838
Restricted cash⁽¹⁾	1,125		—		—
Total cash, cash equivalents and restricted cash	$	157,199	$	108,624	$	180,838

⁽¹⁾ Included in other assets on the consolidated balance sheets.

(G) Property and Equipment, net:

Property and equipment, net consisting of computers, equipment, furniture and fixtures, leasehold improvements, and software, is recorded at cost, less accumulated depreciation. Maintenance and repairs that do not improve or extend the lives of the respective assets are expensed to operations as incurred. Upon disposal, retirement or sale, the related cost and accumulated depreciation are removed from the accounts and any resulting gain or loss is included in the results of operations. Depreciation is recorded for property and equipment using the straight-line method over the estimated useful lives of the assets, which range from three to seven years once the asset is installed and placed into service. Leasehold improvements are amortized using the straight-line method over their estimated useful life or the remaining lease term, whichever is shorter.

The Company reviews the recoverability of its long-lived assets, including the related useful lives, whenever events or changes in circumstances indicate that the carrying amount of a long-lived asset might not be recoverable, based on undiscounted cash flows. If such assets are considered to be impaired, an impairment loss is recognized and is measured as the amount by which the carrying amount of the assets exceed their estimated fair value, which is measured based on the projected discounted future net cash flows arising from the assets.

(H) Operating Leases:

At the inception of a lease, the Company evaluates the lease agreement to determine whether the lease is an operating or capital lease. For operating leases, the Company recognizes rent expense on a straight-line basis over the lease term and records the difference between cash rent payments and the recognition of rent expense as a deferred rent liability. Where lease agreements contain rent escalation clauses, rent abatements and/or concessions, such as rent holidays and tenant improvement allowances, the Company applies them in the determination of straight-line rent expense over the lease term.

Certain lease agreements also require the Company to make additional payments for taxes, insurance, and other operating expenses incurred during the lease period, which are expensed as incurred.

(I) Debt Issuance Costs and Debt Discount:

Debt issuance costs include the costs of debt financings undertaken by the Company, including legal fees, accounting fees, and other direct costs of the financing. Debt issuance costs related to a recognized debt liability are presented on the consolidated balance sheet as a direct deduction from the carrying amount of the debt liability, consistent with debt discounts, and are amortized to interest expense over the term of the related debt using the effective interest method. Further, debt discounts created as a result of the allocation of proceeds received from a debt issuance to warrants issued in conjunction with the debt issuance are amortized to interest expense under the effective interest method over the life of the recognized debt liability.

(J) Contingencies:

The Company may be, from time to time, a party to various disputes and claims arising from normal business activities. The Company continually assesses litigation to determine if an unfavorable outcome would lead to a probable loss or reasonably possible loss which could be estimated. In accordance with the guidance of the FASB on accounting for contingencies, the Company accrues for all contingencies at the earliest date at which the Company deems it probable that a liability has been incurred and the amount of such liability can be reasonably estimated. If the estimate of a probable loss is a range and no amount within the range is more likely than another, the Company accrues the minimum amount in the range. In the cases where the Company believes that a material reasonably possible loss exists, the Company discloses the facts and circumstances of the contingency, including an estimable range, if possible.

(K) Research and Development Expenses:

R&D costs are expensed as incurred. Clinical study costs are accrued over the service periods specified in the contracts and adjusted as necessary based on an ongoing review of the level of effort and costs actually incurred. Milestone payments made in connection with regulatory approvals are capitalized and amortized to cost of revenue over the remaining useful life of the asset. R&D expenses primarily consist of employee-related expenses, such as salaries, share-based compensation, benefits and travel expenses for employees engaged in R&D activities, payments made under third party license agreements, certain costs allocated to the Company for activities performed by RSI and RSG under services agreements with the Company, as well as allocated share-based compensation expense from RSL, and expenses from third parties who conduct R&D activities on behalf of the Company. The Company expenses in-process R&D projects acquired as asset acquisitions which have not reached technological feasibility and which have no alternative future use.

(L) Share-Based Compensation:

Share-based awards to employees and directors are valued at fair value on the date of grant and that fair value is recognized on a straight-line basis over the requisite service period, which is generally the vesting period of the respective award. The Company recognizes forfeitures in the period in which such forfeiture occurs and records share-based compensation expense as though all awards are expected to vest. The Company estimates the grant date fair value, and the resulting share-based compensation expense, using the Black-Scholes option-pricing model, which requires the use of highly subjective assumptions. These assumptions include:


•	Expected Term. The expected term represents the period that the Company’s share-based awards are expected to be outstanding and is determined using the simplified method in accordance with the Securities and Exchange Commission, or SEC, Staff Accounting Bulletin, or SAB, No. 107 and No. 110 (based on the mid-point between the vesting date and the end of the contractual term).

•

Expected Volatility. Because the Company did not have an extended trading history for its common shares, the expected volatility was estimated using weighted average measures of implied volatility and the historical volatility of a peer group of companies for a period equal to the expected life of the stock options. The Company’s peer group of publicly traded biopharmaceutical companies was chosen based on their similar size, stage in the life cycle or area of specialty.


•	Risk-Free Interest Rate. The risk-free interest rate is based on the interest rates paid on securities issued by the U.S. Treasury with a term approximating the expected life of the stock options.


•	Expected Dividend. The Company has never paid, and does not anticipate paying, cash dividends on its common shares. Therefore, the expected dividend yield was assumed to be zero.

Share-based compensation expense associated with time-vesting restricted share awards and restricted stock units is based on the fair value of the Company’s common shares on the grant date, which equals the closing market price of the Company’s common shares on the grant date. The Company recognizes the share-based compensation expense related to these awards on a straight-line basis over the requisite service period, which is generally the vesting period of the respective awards.

Share-based compensation expense associated with restricted share awards subject to market conditions is estimated on the grant date using a Monte Carlo valuation model. The resulting fair value is recognized as share-based compensation expense ratably over the derived service period regardless of whether the market conditions are satisfied.

RSL restricted stock units granted to the Company’s Principal Executive Officer vest upon the achievement of both a performance and market condition, if both are achieved by the contractual expiration date and the Principal Executive Officer has remained in continuous service with RSL or any of its subsidiaries. The Company will recognize share-based compensation expense related to this award upon the achievement of the performance and market conditions throughout the requisite service period.

Share-based payment awards granted by RSL to RSL, RSI, RSG and the Company’s employees are valued by RSL at fair value on the date of grant and that fair value is recognized as share-based compensation expense over the requisite service period. Significant judgment and estimates were used by RSL to estimate the fair value of these awards, as they are not publicly traded. RSL share-based payment awards are subject to specified vesting schedules and requirements (a mix of time-based and performance-based events). The fair value is based on various corporate event-based considerations, including targets for RSL’s post-IPO market capitalization and future financing events. The fair value of each RSL option is estimated on the date of grant using the Black-Scholes closed-form option-pricing model. Share-based compensation expense has been and will continue to be allocated to the Company over the requisite service period over which these RSL share-based payment awards are expected to vest and based on the relative percentage of time utilized by RSL, RSI and RSG employees on the Company’s matters.

No tax benefits for share-based compensation has been recognized in the consolidated statements of shareholders’ equity (deficit) or consolidated statements of cash flows. The Company has not recognized, and does not expect to recognize in the near future, any tax benefits related to share-based compensation as a result of its full valuation allowance on net deferred tax assets and net operating loss carryforwards.

(M) Takeda Warrant Liability:

The Company recorded the Takeda warrant liability at its estimated fair value in the consolidated balance sheets. The Company remeasured the estimated fair value of the Takeda warrant liability each reporting period in which it was outstanding and recorded the change in the fair value in the consolidated statements of operations and comprehensive loss. The Takeda warrant liability expired on April 30, 2017.

(N) Income Taxes:

Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and the respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance is recorded when, after consideration of all positive and negative evidence, it is not more likely than not that the Company’s deferred tax assets will be realizable.

When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position as well as consideration of the available facts and circumstances. Interest and/or penalties related to income tax matters are recognized as a component of income tax expense as incurred.

(O) Net Loss per Common Share:

Basic net loss per common share is computed by dividing net loss applicable to common shareholders by the weighted-average number of common shares outstanding during the period, reduced, where applicable, for outstanding yet unvested shares of restricted common stock. The computation of diluted net loss per common share is based on the weighted-average number of common shares outstanding during the period plus, when their effect is dilutive, incremental shares consisting of shares subject to stock options, restricted stock units, restricted share awards, and warrants. In periods in which the Company reports a net loss, all common share equivalents are deemed anti-dilutive such that basic net loss per common share and diluted net loss per common share are equal. Potentially dilutive common shares have 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 shares outstanding for basic and diluted net loss per common share.

As of March 31, 2019, 2018 and 2017, potentially dilutive securities were as follows:



	March 31,
	2019	2018	2017
Stock options	5,396,465	3,549,405	1,525,857
Restricted share awards (unvested)	916,679	1,198,735	1,128,222
Restricted stock units (unvested)	39,387	15,000	—
Warrants	73,710	73,710	—
Total	6,426,241	4,836,850	2,654,079

(P) Fair Value Measurements:

The Company utilizes fair value measurement guidance prescribed by accounting standards to value its financial instruments. The guidance establishes a fair value hierarchy for financial instruments measured at fair value that distinguishes between assumptions based on market data (observable inputs) and the Company’s own assumptions (unobservable inputs). Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability, and are developed based on the best information available in the circumstances.

Fair value is defined as the exchange price, or exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the reporting date. As a basis for considering market participant assumptions in fair value measurements, the guidance establishes a three-tier fair value hierarchy that distinguishes among the following:


•	Level 1-Valuations are based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access.


•	Level 2-Valuations are based on quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active and models for which all significant inputs are observable, either directly or indirectly.


•	Level 3-Valuations are based on inputs that are unobservable (supported by little or no market activity) and significant to the overall fair value measurement.

To the extent the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement.

The Company’s financial instruments include cash, cash equivalents consisting of commercial paper and money market funds, accounts payable and debt. Cash, cash equivalents, and accounts payable are stated at their respective historical carrying amounts, which approximate fair value due to their short-term nature. The carrying value of the Company’s debt approximates fair value based on current interest rates for similar types of borrowings and is included in Level 2 of the fair value hierarchy.

(Q) Foreign Currency:

The results of the Company’s non-U.S. dollar based functional currency operations are translated to U.S. dollars at the average exchange rates during the period. The Company’s assets and liabilities are translated using the current exchange rate as of the balance sheet date and shareholders’ equity (deficit) is translated using historical rates. Adjustments resulting from the translation of the financial statements of the Company’s foreign functional currency subsidiaries into U.S. dollars are excluded from the determination of net loss and are accumulated in a separate component of shareholders’ equity (deficit). Foreign currency exchange transaction gains and losses are included in other expense (income), net in the Company’s consolidated statements of operations.

(R) Recently Adopted Accounting Standards:

In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (a consensus of the FASB Emerging Issues Task Force, or ASU 2016-18. The amendments in this update require that amounts generally described as restricted cash and restricted cash equivalents be included within cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 is effective for annual reporting periods beginning after December 15, 2017 and is required to be adopted using a retrospective approach, if applicable, with early adoption permitted. The Company adopted ASU 2016-18 on April 1, 2018. The adoption of ASU 2016-18 did not have a material impact on the Company’s consolidated financial statements and related disclosures.

In March 2018, the FASB issued ASU 2018-05, Income Taxes (Topic 740): Amendments to SEC Paragraphs Pursuant to SEC Staff Accounting Bulletin No. 118 (SAB No. 118), or ASU 2018-05. ASU 2018-05 adds various SEC paragraphs pursuant to the issuance of the December 2017 SEC Staff Accounting Bulletin (SAB) No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act, which was effective immediately. The SEC issued SAB No. 118 to address concerns about reporting entities’ ability to comply timely with the accounting requirements to recognize the effects of the Tax Cuts and Jobs Act in the period of enactment. SAB No. 118 allows disclosure that timely determination of some or all of the income tax effects from the Tax Cuts and Jobs Act are incomplete by the due date of the financial statements and if possible to provide a reasonable estimate. As permitted by SAB No. 118, the Company recorded provisional amounts in the year ended March 31, 2018 and finalized its accounting for these provisional estimates based on guidance, interpretations and all available data in the year ended March 31, 2019. No material adjustments were made to the provisional amounts.

In October 2016, the FASB issued ASU 2016-16, Intra-Entity Transfers of Assets Other Than Inventory, or ASU 2016-16. ASU 2016-16 requires the income tax consequences of intra-entity transfers of assets, other than inventory, to be recognized when the transfer occurs. The new standard was effective for the Company on April 1, 2018 and was adopted using a modified retrospective approach. The adoption of this standard resulted in the recognition of a deferred tax asset of $38.7 million with a corresponding valuation allowance of $38.7 million.

(S) Recently Issued Accounting Standards Not Yet Adopted:

(1) Leases:

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), which is a comprehensive new lease standard that amends various aspects of existing accounting guidance for leases. Topic 842 was subsequently amended by ASU 2018-01, Land Easement Practical Expedient for Transition to Topic 842; ASU 2018-10, Codification Improvements to Topic 842, Leases; and ASU 2018-11, Targeted Improvements. The core principle of Topic 842 will require lessees to recognize on the consolidated balance sheets a liability to make lease payments and a right-of-use, or ROU, asset representing its right to use the underlying asset for the lease term for both finance and operating leases with lease terms greater than twelve months. The lease liability will be measured at the present value of the unpaid lease payments and the ROU asset will be derived from the calculation of the lease liability. Lease payments will include fixed and in-substance fixed payments, variable payments based on an index or rate, exercise price of purchase options that are reasonably certain to be exercised, termination penalties, and probable amounts the lessee will owe under a residual value guarantee. Topic 842 also requires lessees to disclose key information about leasing arrangements. Topic 842 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2018, with early adoption permitted.

A modified retrospective transition approach is required, applying the new standard to all leases existing at the date of initial application (“Transition Date”). An entity may choose to use either (i) its effective date or (ii) the beginning of the earliest comparative period presented in the financial statements as its date of initial application. The Company plans to adopt the new standard on April 1, 2019 and use the effective date as its date of initial application.

The new standard provides a number of optional practical expedients in transition. The Company expects to elect the “package of practical expedients,” which permits it to not reassess under the new standard its prior conclusions about lease identification, lease classification, and initial direct costs. As a result, the Company will in effect, continue to account for existing leases - i.e. leases for which the commencement date is before April 1, 2019 - in accordance with Topic 840 throughout the entire lease term, including periods after the effective date, with the exception that the Company will apply the new balance sheet recognition guidance for operating leases and apply Topic 842 for remeasurements and modifications after the Transition Date.

While the Company continues to assess all the effects of adoption, the Company believes the most significant effects relate to the recognition of a ROU asset and corresponding liability on its consolidated balance sheet, primarily related to its existing facility operating lease, and providing new disclosures with regards to the Company’s leasing activities. The Company currently expects that the adoption of the new standard will result in the recording of a ROU asset of approximately $9.0 million to $10.0 million and a lease liability of approximately $10.0 million to $11.0 million.

(2) Others:

In February 2018, the FASB issued ASU 2018-02, Income Statement- Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, or ASU 2018-02. ASU 2018-02 allows companies to reclassify stranded tax effects resulting from the newly enacted federal corporate income tax rate under the Tax Cuts and Jobs Act, from accumulated other comprehensive (loss) income to retained earnings. ASU 2018-02 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018 and early adoption is permitted. The Company plans to adopt this new standard on April 1, 2019. The Company does not expect that the adoption of ASU 2018-02 will have a material impact on its consolidated financial statements and related disclosures.

In June 2018, the FASB issued ASU 2018-07, Compensation- Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting, or ASU 2018-07. ASU 2018-07 simplifies the accounting for share-based payments to nonemployees by aligning it with the accounting for share-based payments to employees, with certain exceptions. ASU 2018-07 is effective for interim and annual reporting periods beginning after December 15, 2018 and early adoption is permitted. The Company plans to adopt the new standard on April 1, 2019. The Company does not expect that the adoption of ASU 2018-07 will have a material impact on its consolidated financial statements and related disclosures.

In August 2018, the FASB issued ASU 2018-15, Intangibles- Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract, or ASU 2018-15, which amends ASC 350-40, Internal-Use Software, to include in its scope implementation costs of a cloud computing arrangement that is a service contract. Consequently, the accounting for costs incurred to implement a cloud computing arrangement that is a service arrangement is aligned with the guidance on capitalizing costs associated with developing or obtaining internal-use software. ASU 2018-15 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2019. Early adoption is permitted, including adoption in any interim period. The Company is currently assessing the impact the adoption of this standard will have on its consolidated financial statements and related disclosures.

License Agreement

12 Months Ended

Mar. 31, 2019

Other Liabilities Disclosure [Abstract]

License Agreement

On April 29, 2016, the Company entered into a license agreement pursuant to which Takeda granted to the Company an exclusive, royalty-bearing license under certain patents and other intellectual property controlled by Takeda to develop and commercialize relugolix and MVT-602, in exchange for the following:


•	The Company issued and delivered 5,077,001 of its common shares upon entry into the license agreement.

•

The Company will pay Takeda a fixed, high single-digit royalty on net sales of relugolix and MVT-602 products in the Company’s territory, subject to certain agreed reductions. Takeda will pay the Company a royalty at the same rate as the Company’s on net sales of relugolix products for prostate cancer in Japan and certain other Asian countries, subject to certain agreed reductions. Royalties are required to be paid, on a product-by-product and country-by-country basis, until the latest of the expiration of the last to expire valid claim of a licensed patent covering such product in such country, the expiration of regulatory exclusivity for such product in such country, or 10 years after the first commercial sale of such product in such country. Under this license agreement, there are no payments upon the achievement of clinical development or marketing approval milestones.

•

The Company issued a warrant to Takeda to purchase an indeterminate number of capital shares. The warrant entitled Takeda, together with its affiliates, to maintain a 12% ownership interest in the Company, as determined after such exercise, through the later of (i) April 30, 2017 or (ii) the final closing of the Company’s IPO, unless earlier terminated upon a change in control. The Company issued and delivered a total of 2,343,624 of its common shares to Takeda under this warrant prior to its expiration on April 30, 2017.

For the consideration above, the Company also received a small quantity of relugolix and MVT-602, and certain historical R&D records. The Company did not hire, or receive, any Takeda workforce or employees working on relugolix and MVT-602, or any research, clinical or manufacturing equipment. The Company did not assume any contracts, licenses or agreements between Takeda and any third party with respect to relugolix and MVT-602. If the license agreement is terminated in its entirety or with respect to relugolix for prostate cancer, other than for safety reasons or by the Company for Takeda’s uncured material breach, prior to receipt of the first regulatory approval of relugolix for prostate cancer in Japan, then the Company must either reimburse Takeda for its out of pocket costs and expenses directly incurred in connection with Takeda’s completion of the relugolix development for prostate cancer, up to an agreed upon cap, or complete by itself the conduct of any clinical trials of relugolix for prostate cancer that are ongoing as of the effective date of such termination, at its cost and expense.

As the intellectual property and inventory acquired had no alternative future use, the Company recorded $13.1 million as R&D expense at the closing date of the acquisition of the rights, April 29, 2016, which consisted of $7.7 million for the estimated fair value of the 5,077,001 common shares issued and $5.4 million for the estimated fair value of the warrant liability.

The estimation of the fair value of the common shares considered factors including the following: the estimated present value of the Company’s future cash flows; industry information such as market size and growth; market capitalization of comparable companies and the estimated value of transactions such companies have engaged in; and macroeconomic conditions.

The estimation of the fair value of the warrant liability was determined based on a Monte Carlo simulation model which requires various highly subjective unobservable inputs.

Financing Arrangements

12 Months Ended

Mar. 31, 2019

Debt Disclosure [Abstract]

Financing Arrangements

(A) NovaQuest:

In October 2017, the Company, its subsidiaries, as guarantors, and NovaQuest Capital Management, or NovaQuest, entered into (i) a Securities Purchase Agreement, or the NovaQuest Securities Purchase Agreement, and (ii) an Equity Purchase Agreement, or the NovaQuest Equity Purchase Agreement. Pursuant to the NovaQuest Securities Purchase Agreement, the Company had the option, at its discretion, to issue up to $60.0 million aggregate principal amount of notes to NovaQuest and concurrent with each purchase of notes, NovaQuest was obligated to purchase up to $20.0 million of the Company’s common shares on a pro rata basis, subject to certain terms and conditions, through December 31, 2018. The equity purchase price for each such purchase was equal to 105% of the average of the volume-weighted average price for the five consecutive trading days immediately prior to the relevant purchase date. The Company committed that it would issue at least $30.0 million aggregate principal amount of notes through December 31, 2018, subject to certain terms and conditions. The Company issued $6.0 million aggregate principal amount in October 2017 and $54.0 million aggregate principal amount in December 2018. With the issuance of $6.0 million aggregate principal amount of notes in October 2017, NovaQuest purchased 138,361 common shares for $2.0 million, and with the issuance of $54.0 million aggregate principal amount of notes in December 2018, NovaQuest purchased 1,082,977 common shares for $18.0 million.

The notes bear interest at a rate of 15% per annum, of which 5% is payable quarterly, and 10% is payable on a deferred basis on the earlier of the Amortization Date (as defined below) and the repayment in full of the notes. The notes mature on October 16, 2023. The Company will be required to amortize the principal amount of the notes in equal quarterly installments commencing on November 1, 2020, subject to extension at the Company’s option to November 1, 2021, or the Amortization Date, provided certain terms and conditions are met. Early redemption of the notes is subject to a redemption charge. The Company’s obligations under the NovaQuest Securities Purchase Agreement are secured by a second-lien security interest in substantially all of the Company’s and its subsidiaries’ respective assets (other than intellectual property). The NovaQuest Securities Purchase Agreement includes customary affirmative and restrictive covenants and representations and warranties, including a minimum cash covenant that applies commencing on the Amortization Date, and also includes customary events of default. Upon the occurrence of an event of default, a default interest rate of an additional 5% may be applied to the outstanding note balance and NovaQuest may declare all outstanding obligations immediately due and payable and take such other actions as set forth in the NovaQuest Securities Purchase Agreement.

Pursuant to the NovaQuest Equity Purchase Agreement, NovaQuest committed to purchase up to an additional $20.0 million of the Company’s common shares from time to time at the Company’s discretion through December 31, 2018, with an option to extend the commitment through December 31, 2019, subject to certain terms and conditions. The Company committed that it would exercise its option to sell and issue a minimum of $10.0 million of its common shares under the NovaQuest Equity Purchase Agreement through December 31, 2018, subject to certain terms and conditions. In December 2018, the Company exercised this option and issued and sold 1,203,307 common shares for $20.0 million. The purchase price for the common shares issued was equal to 105% of the average of the volume-weighted average price for the five consecutive trading days immediately prior to the relevant purchase date.

The Company incurred financing costs related to the NovaQuest Securities Purchase Agreement of $1.0 million. During the years ended March 31, 2019 and 2018, interest expense included $0.4 million and $0.2 million, respectively, of amortized deferred financing costs related to the NovaQuest notes. During the year ended March 31, 2019, the Company paid NovaQuest an annual debt administration fee of $0.3 million, which has been deferred and is being amortized over twelve months.

Outstanding debt obligations to NovaQuest are as follows (in thousands):



	March 31,
	2019			2018

Principal amount	$	60,000		$	6,000
Less: unamortized debt issuance costs	(756		)	(854		)
Loan payables less unamortized debt issuance costs	59,244			5,146
Less: current maturities	—			—
Long-term debt, net of current maturities and unamortized debt issuance costs	$	59,244		$	5,146

(B) Hercules:

In October 2017, the Company, its subsidiaries, as guarantors, and Hercules Capital, Inc., or Hercules, entered into a Loan Agreement, or the Hercules Loan Agreement, which provided up to $40.0 million principal amount of term loans, or the Term Loans. A first tranche of $25.0 million principal amount was funded upon execution of the Hercules Loan Agreement in October 2017 and the remaining $15.0 million principal amount was funded in March 2018. The Term Loans bear interest at a variable per annum rate at the greater of (i) the prime rate plus 4.00% and (ii) 8.25%. The interest rate on the Term Loans was 9.50% as of March 31, 2019. Pursuant to the terms of the Hercules Loan Agreement, the Term Loan Maturity Date has been extended from May 1, 2021 to November 1, 2021 as a result of the achievement of a financing milestone during July 2018. The Company is obligated to make monthly interest payments during the Interest-only Period, subject to certain terms and conditions, followed by monthly installments of principal and interest through the maturity date. The Interest-only Period has been extended from June 1, 2019 to December 1, 2019 as a result of the achievement of a financing milestone during July 2018 and may be further extended until June 1, 2020 if a certain clinical development milestone is met, as specified in the Hercules Loan Agreement. Prepayment of the Term Loan is subject to a prepayment charge. The Company is also obligated to pay an end of term charge of 6.55% of the principal amount of the Term Loans funded under the Hercules Loan Agreement, on the earlier of the maturity date or the date that the Term Loans otherwise become due and payable. The Company’s obligations under the Hercules Loan Agreement are secured by a first-lien security interest in substantially all of the Company’s and its subsidiaries’ respective assets (other than intellectual property). The Hercules Loan Agreement includes customary affirmative and restrictive covenants and representations and warranties, including a minimum cash covenant that ceases to apply if the Company achieves both the clinical development and financing milestones as set forth in the Hercules Loan Agreement. The Hercules Loan Agreement also includes customary events of default. Upon the occurrence of an event of default, a default interest rate of an additional 5.00% may be applied to the outstanding principal balance, and Hercules may declare all outstanding obligations immediately due and payable and take such other actions as set forth in the Hercules Loan Agreement.

Concurrent with each funding of the Term Loans, the Company was required to issue to Hercules a warrant, or the Warrants, to purchase a number of its common shares equal to 3.00% of the principal amount of the relevant Term Loan funded divided by the exercise price, which is based on the lowest three-day volume-weighted average price for the three consecutive trading days prior to the funding date for such Term Loan. The Warrants may be exercised on a cashless basis, and are immediately exercisable through the seventh anniversary of the applicable funding date. In connection with the first tranche funded under the Hercules Loan Agreement, the Company issued a Warrant to Hercules exercisable for an aggregate of 49,800 of its common shares at an exercise price of $15.06 per common share. Concurrent with the funding of the second tranche, the Company issued a Warrant to Hercules exercisable for an aggregate of 23,910 of its common shares at an exercise price of $18.82 per common share. The Company accounted for the Warrants as equity instruments since they were indexed to the Company’s common shares and met the criteria for classification in shareholders’ equity (deficit). The relative fair value of the Warrants related to the first and second tranche funding were approximately $0.5 million and $0.3 million, respectively, and were treated as a discount to the Term Loans. This amount is being amortized to interest expense using the effective interest method over the life of the Term Loans. The Company estimated the fair value of the Warrants using the Black-Scholes model based on the following key assumptions:



	Tranche 1	Tranche 2

Exercise price	$15.06	$18.82
Common share price on date of issuance	$14.39	$18.96
Volatility	73.2%	72.3%
Risk-free interest rate	2.15%	2.78%
Expected dividend yield	—%	—%
Contractual term (in years)	7.00	7.00

The Company issued the first tranche of the Term Loans at a discount of $2.1 million, including the relative fair value of the related Warrant, and incurred financing costs of $1.3 million. The second tranche of the Term Loans was issued at a discount of $1.3 million, including the relative fair value of the related Warrant. During the years ended March 31, 2019 and 2018, interest expense included $1.7 million and $0.5 million, respectively, of amortized debt discount and issuance costs related to the Term Loans.

Outstanding debt obligations to Hercules are as follows (in thousands):



	March 31,
	2019			2018

Principal amount	$	40,000		$	40,000
End of term charge	2,620			2,620
Less: unamortized debt discount and issuance costs	(2,482		)	(4,142		)
Loan payables less unamortized debt discount and issuance costs	40,138			38,478
Less: current maturities	(6,142		)	—
Long-term debt, net of current maturities and unamortized debt discount and issuance costs	$	33,996		$	38,478

Annual maturities of debt outstanding as of March 31, 2019 are as follows (in thousands):



Years Ended March 31,

2020	$	6,142
2021	28,854
2022	32,696
2023	18,462
2024	13,846
Thereafter	—
Total	$	100,000

Related Party Transactions	12 Months Ended
Related Party Transactions	Mar. 31, 2019
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions (A) Services Agreements: In July 2016, the Company entered into a services agreement with RSI, effective April 29, 2016, under which RSI agreed to provide certain administrative and R&D services to the Company. Under this services agreement, the Company pays or reimburses RSI for expenses it, or third parties acting on its behalf, incurs for the Company. For any general and administrative, or G&A, and R&D activities performed by RSI employees, RSI charges the Company based on the relative percentage of time utilized on Company matters by the respective employee. All other third-party pass thru costs are billed to the Company at cost. The consolidated financial statements include third-party expenses incurred on behalf of the Company that have been paid by RSI and RSL. In February 2017, the Company and MSI amended and restated the services agreement, effective as of November 11, 2016, to include Myovant Sciences GmbH, or MSG, as a services recipient. In addition, in February 2017, MSG entered into a separate services agreement with RSG, effective as of November 11, 2016, for the provisioning of services by RSG to MSG in relation to services related to clinical development, administrative and finance and accounting activities. The Company refers to the amended and restated services agreement with RSI and the services agreement with RSG, collectively, as the Services Agreements. Under the Services Agreements, for the years ended March 31, 2019, 2018 and 2017, the Company incurred expenses (inclusive of third party pass thru costs billed to the Company) of $4.8 million, $7.7 million and $9.2 million, respectively, inclusive of the mark-up. These amounts are included in R&D expenses and G&A expenses based upon the nature of the service performed under the Services Agreements. The Company has replaced many of the services previously provided by RSI and RSG with its own internally developed capabilities or external professional service providers. The level of support the Company receives from RSI and RSG is expected to continue to decrease as the Company further decentralizes its activities from RSL. (B) Share-Based Compensation Expense Allocated to the Company by RSL: Share-based compensation expense has been and will continue to be allocated to the Company by RSL over the requisite service period over which RSL common share awards and RSL options are expected to vest and based upon the relative percentage of time utilized by RSL, RSI and RSG employees on Company matters. In relation to the RSL common share awards and options issued by RSL to RSL, RSI, RSG and the Company’s employees, the Company recorded share-based compensation expense of $0.6 million, $1.0 million and $4.9 million, respectively, for the years ended March 31, 2019, 2018 and 2017. Refer to Note 9 for further details. (C) Private Placement with RSL: See Note 7(D) for information regarding the Private Placement with RSL. (D) Option Agreement with RSL: In June 2016, the Company entered into an option agreement with RSL pursuant to which RSL granted to the Company an option to acquire the rights to products to which RSL or any nonpublic affiliate of RSL acquires the rights (other than a relugolix product or a competing product) for uterine fibroids or endometriosis, or for which the primary target indication is advanced prostate cancer. The Company’s option is exercisable at any time during the period commencing upon the completion of its IPO and ending two years following the date of first commercial sale of a relugolix product in a major market country. If the Company elects to exercise its option for a product, it will be required to reimburse RSL for 110% of any payments made by RSL or its affiliate for such product, and will receive an assignment of the agreement through which RSL or its affiliate acquired the rights to such product. (E) Information Sharing and Cooperation Agreement with RSL: In July 2016, the Company entered into an information sharing and cooperation agreement, or the Cooperation Agreement, with RSL. The Cooperation Agreement, among other things: (1) obligates the Company to deliver periodic financial statements and other financial information to RSL and to comply with other specified financial reporting requirements; and (2) requires the Company to supply certain material information to RSL to assist it in preparing any future SEC filings. Subject to specified exceptions, the Cooperation Agreement will terminate upon the earlier of the mutual written consent of the parties or when RSL is no longer required by U.S. GAAP to consolidate the Company’s financial statements, 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. On May 24, 2019, the Company entered into Amendment No. 1 to the Cooperation Agreement, pursuant to which RSL has agreed, in connection with each of the Company’s next three public offerings of its common shares, that RSL will (1) provide to the Company and the underwriter(s) engaged by the Company in connection with such public offering an indication of interest for RSL to participate as a purchaser in such public offerings, and (2) enter into a customary lock-up agreement with the underwriters in connection with such public offerings. (F) Manufacture and Supply Agreement: In June 2016, the Company and one of Takeda’s affiliates, Takeda Pharmaceutical Company Limited, or Takeda Limited, entered into an agreement for the manufacture and supply of relugolix. Under this agreement, Takeda Limited is supplying the Company, and the Company has obtained from Takeda Limited, all of its requirements for relugolix drug substance and drug product to be used under its development plans for all indications. Takeda Limited is also assisting the Company with a technical transfer of the manufacturing process for relugolix to it and its designee and the Company is paying the expenses related to such transfer. (G) Commercial Manufacturing and Supply Agreement: In May 2018, the Company entered into a Commercial Manufacturing and Supply Agreement with Takeda, or the Takeda Commercial Supply Agreement. Pursuant to the Takeda Commercial Supply Agreement, Takeda has agreed to supply the Company and the Company has agreed to obtain from Takeda certain quantities of relugolix drug substance according to agreed-upon quality specifications and in order to commercialize relugolix in accordance with the Takeda Agreement. Under the Takeda Commercial Supply Agreement, the Company will pay Takeda a fixed price per kilogram of relugolix drug substance through December 31, 2019. The Company has made and Takeda has accepted an initial firm order to supply relugolix drug substance to the Company through December 31, 2019. For relugolix drug substance manufactured or delivered on or after such date, the Company will pay Takeda a price per kilogram of relugolix drug substance to be agreed upon between the parties at the beginning of each fiscal year. In addition, under the Takeda Commercial Supply Agreement, Takeda has agreed to assist with the transfer of technology and Takeda manufacturing know-how to a second contract manufacturing organization of the Company’s subsidiary, Myovant Sciences GmbH. The Company has agreed to reimburse Takeda for all internal costs, and external costs, charges, and expenses, in each case, reasonably incurred by Takeda in connection with any technology transfer services. The initial term of the Takeda Commercial Supply Agreement began on May 30, 2018 and will continue for five years. At the end of the initial term, the Takeda Commercial Supply Agreement automatically renews for successive one-year terms, unless either party gives notice of termination to the other at least 12 months prior to the end of the then-current term. The Takeda Commercial Supply Agreement may be terminated by either party upon 90 days’ notice of an uncured material breach of its terms by the other party, or immediately upon notice to the other party of a party’s bankruptcy. Each party will also have the right to terminate the Takeda Commercial Supply Agreement, in whole or in part, for any reason upon 180 days’ prior written notice to the other party, provided that any then-open purchase orders, including the initial firm order for relugolix drug substance through December 31, 2019, will remain in effect and be binding on both parties. The Takeda Commercial Supply Agreement, including any then-open purchase order thereunder, will terminate immediately upon the termination of the Takeda Agreement in accordance with its terms. The Takeda Commercial Supply Agreement also includes customary provisions relating to, among others, delivery, inspection procedures, warranties, quality management, storage, handling and transport, intellectual property, confidentiality and indemnification.

Shareholders' Equity (Deficit)	12 Months Ended
Shareholders' Equity (Deficit)	Mar. 31, 2019
Equity [Abstract]
Shareholders' Equity (Deficit)	Shareholders’ Equity (Deficit) (A) Overview: The Company’s Memorandum of Association, filed on February 2, 2016 in Bermuda, authorized the creation of one class of shares. As of March 31, 2019, the Company had 564,111,242 shares authorized with a par value of $0.000017727 per share. (B) Initial Public Offering and Reverse Stock Split: On October 18, 2016, the Company’s board of directors approved a 1-for-1.7727 reverse stock split of the Company’s outstanding common shares. The reverse stock split became effective on October 18, 2016. These consolidated financial statements give retroactive effect to the reverse stock split for all periods presented. On November 1, 2016, the Company completed its IPO of common shares. The Company sold 14,500,000 common shares at a price of $15.00 per common share, for gross proceeds of $217.5 million. The Company received net proceeds of $200.0 million, after deducting $15.2 million in underwriting discounts and commissions and $2.3 million in offering costs paid by the Company. (C) Underwritten Public Equity Offering of Common Shares: In July and August 2018, the Company completed an underwritten public equity offering of 3,533,399 of its common shares (including 200,065 common shares issued and sold upon the partial exercise of the underwriters’ option to purchase additional shares) at a public offering price of $22.50 per common share. After deducting the underwriting discounts and commissions and offering costs paid by the Company, the net proceeds to the Company in connection with the underwritten public equity offering, including from the partial option exercise, were approximately $74.4 million. (D) Private Placement with RSL: In April 2018, the Company entered into a share purchase agreement, or the Purchase Agreement, with RSL, its controlling shareholder, pursuant to which the Company sold to RSL 1,110,015 of its common shares at a purchase price of $20.27 per common share, for gross proceeds of $22.5 million, in a private placement, or the Private Placement. (E) At-the-Market Equity Offering Program: In April 2018, the Company entered into a sales agreement, or the Sales Agreement, with Cowen and Company, LLC, or Cowen, to sell its common shares having an aggregate offering price of up to $100.0 million from time to time through an “at-the-market” equity offering program under which Cowen acts as the Company’s agent. During the year ended March 31, 2019, the Company issued and sold 3,970,129 of its common shares under the Sales Agreement. The common shares were sold at a weighted-average price of $21.91 per common share for aggregate net proceeds to the Company of approximately $84.1 million, after deducting underwriting commissions and offering costs paid by the Company. As of March 31, 2019, the Company had approximately $13.0 million of capacity available to it under its “at-the-market” equity offering program. In April 2019, the Company issued and sold an additional 106,494 common shares for aggregate net proceeds of $2.5 million pursuant to this program. (F) Issuance of Equity Instruments to NovaQuest and Hercules: In October 2017, the Company issued and sold 138,361 common shares to NovaQuest for $2.0 million in accordance with the terms of the NovaQuest Securities Purchase Agreement. In December 2018, the Company issued and sold 1,082,977 common shares to NovaQuest for $18.0 million in accordance with the NovaQuest Securities Purchase Agreement and issued and sold 1,203,307 common shares to NovaQuest for $20.0 million in accordance with the NovaQuest Equity Purchase Agreement. In October 2017, the Company issued a Warrant to Hercules exercisable for 49,800 of its common shares at an exercise price of $15.06 per common share and in March 2018, the Company issued a Warrant to Hercules exercisable for an aggregate of 23,910 of its common shares at an exercise price of $18.82 per common share. Additional information is included in Note 5, “Financing Arrangements.” (G) Takeda Warrant Liability: During the year ended March 31, 2017, the Company issued 2,339,192 common shares to Takeda upon the automatic exercise of the Takeda warrant, which was due to the issuance of 153,846 common shares initiated by the grant of a restricted share award for 1,128,222 common shares, issuance of 208,077 common shares initiated by the grant of options to purchase 1,525,857 common shares and the issuance of an additional 1,977,269 common shares to Takeda upon the closing of the Company’s IPO, based upon the sale and issuance of 14,500,000 common shares to investors in the IPO. During the year ended March 31, 2018, the Company issued 4,432 common shares to Takeda upon the automatic exercise of the Takeda warrant, which was initiated by the grant of options to purchase 32,500 common shares in April 2017. The warrant expired on April 30, 2017.

Income Taxes

12 Months Ended

Mar. 31, 2019

Income Tax Disclosure [Abstract]

Income Taxes

The loss before income taxes and the related tax expense (benefit) are as follows (in thousands):



	Years Ended March 31,
	2019			2018			2017
Loss before income taxes:
United States	$	(11,246	)	$	(7,229	)	$	(2,924	)
Switzerland	(247,445		)	(129,261		)	(29,745		)
Bermuda	(14,357		)	(6,513		)	(50,845		)
Other⁽¹⁾	(27		)	(39		)	—
Total loss before income taxes	$	(273,075	)	$	(143,042	)	$	(83,514	)

Current taxes:
United States	$	473		$	13		$	125
Switzerland	—			—			—
Bermuda	—			—			—
Other⁽¹⁾	3			(8		)	9
Total current tax expense	476			5			134
Deferred taxes:
United States	—			208			(208		)
Switzerland	—			—			—
Bermuda	—			—			—
Other⁽¹⁾	—			—			—
Total deferred tax expense (benefit)	—			208			(208		)
Total income tax expense (benefit)	$	476		$	213		$	(74	)


(1)	Primarily United States state and local, Ireland and United Kingdom activity.

A reconciliation of income tax expense (benefit) computed at the Bermuda statutory rate to income tax expense (benefit) reflected in the consolidated financial statements is as follows (dollars in thousands):



	Years Ended March 31,
	2019					2018					2017
Income tax benefit at Bermuda statutory rate	$	—		—	%	$	—		—	%	$	—		—	%
Foreign rate differential⁽²⁾	(31,252		)	11.44		(14,802		)	10.35		(7,592		)	9.09
Valuation allowance	32,335			(11.83	)	13,966			(9.77	)	7,378			(8.83	)
Tax reform	—			—		1,049			(0.73	)	—			—
Other	(607		)	0.22		—			—		140			(0.17	)
Total income tax expense (benefit)	$	476		(0.17	)%	$	213		(0.15	)%	$	(74	)	0.09	%


(2)	Primarily related to current tax on United States operations including permanent and temporary differences (e.g. research and development credits, etc.) as well as operations in Switzerland and the United Kingdom at rates different than the Bermuda rate.

The Company’s effective tax rate for the years ended March 31, 2019, 2018 and 2017 was (0.17)%, (0.15)% and 0.09%, respectively, and is driven by the Company’s jurisdictional earnings by location and a valuation allowance that eliminates the Company’s global net deferred tax assets.

Deferred taxes reflect the tax effects of the differences between the amounts recorded as assets and liabilities for financial reporting purposes and the comparable amounts recorded for income tax purposes. Significant components of the deferred tax assets and liabilities as of March 31, 2019 and 2018 are as follows (in thousands):



	March 31,
	2019			2018
Deferred tax assets:
Research tax credits	$	7,224		$	2,948
Net operating losses⁽³⁾	38,194			16,045
Share-based compensation	6,106			2,380
Intangibles⁽⁴⁾	38,673			—
Other	2,539			169
Subtotal	92,736			21,542
Valuation allowance	(92,330		)	(21,367		)

Deferred tax liabilities:
Depreciation	(406		)	(175		)
Total deferred tax assets	$	—		$	—

(3)

The Company operates under a tax holiday in Switzerland which is effective through March 31, 2027. The tax holiday is conditional upon the Company meeting certain employment thresholds. The impact of this tax holiday did not impact the Company’s income tax expense for the period but has been accounted for in considering the tax effected net operating losses for this jurisdiction disclosed above.

(4) In October 2016, the FASB issued ASU 2016-16, Intra-Entity Transfers of Assets Other Than Inventory, or ASU 2016-16. ASU 2016-16 requires the income tax consequences of intra-entity transfers of assets, other than inventory, to be recognized when the transfer occurs. The new standard was effective for the Company on April 1, 2018 and was adopted using a modified retrospective approach. The adoption of this standard resulted in the recognition of a deferred tax asset of $38.7 million with a corresponding valuation allowance of $38.7 million.

As of March 31, 2019, the Company’s net operating losses in Switzerland, Ireland, and the United Kingdom were $376.2 million, $32 thousand, and $14.4 million, respectively. The Switzerland net operating losses will begin to expire on March 31, 2025. The net operating losses in Ireland and the United Kingdom can be carried forward indefinitely with annual usage limitations where applicable. As of March 31, 2019, the Company has research and development credit carryforwards in the United States in the amount of $7.2 million which will begin to expire on March 31, 2037.

The Company assesses the realizability of the 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. Due to the Company’s cumulative loss position which provides significant negative evidence difficult to overcome, the Company has recorded a valuation allowance of $92.3 million as of March 31, 2019 representing the portion of the deferred tax asset that is not more likely than not to be realized. The amount of the deferred tax asset considered realizable, could be adjusted for future factors that would impact the assessment of the objective and subjective evidence of the Company. The Company will continue to assess the realizability of deferred tax assets at each balance sheet date in order to determine the proper amount, if any, required for a valuation allowance.

There are outside basis differences related to the Company’s investment in subsidiaries for which no deferred taxes have been recorded as these would not be subject to tax on repatriation as Bermuda has no tax regime for Bermuda exempted limited companies, and the United Kingdom tax regime relating to company distributions generally provides for exemption from tax for most overseas profits, subject to certain exceptions.

The Company is subject to tax and will file income tax returns in the United Kingdom, Switzerland, Ireland, and the United States federal and certain state and local jurisdictions. The Company is subject to tax examinations for tax years ended March 31, 2017 and forward in all applicable income tax jurisdictions. Tax audits and examinations can involve complex issues, interpretations and judgments. The resolution of matters may span multiple years particularly if subject to litigation or negotiation. The Company believes it has appropriately recorded its tax position using reasonable estimates and assumptions, however the potential tax benefits may impact the results of operations or cash flows in the period of resolution, settlement or when the statutes of limitations expire. There are no uncertain tax benefits recorded as of March 31, 2019.

Share-Based Compensation

12 Months Ended

Mar. 31, 2019

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Share-Based Compensation

(A) Myovant 2016 Equity Incentive Plan:

In June 2016, the Company adopted its 2016 Equity Incentive Plan, or as amended, the 2016 Plan, under which 4.5 million common shares were originally reserved for issuance. Pursuant to the “evergreen” provision contained in the 2016 Plan, the number of shares reserved for issuance under the 2016 Plan automatically increases on April 1 of each year, commencing on (and including) April 1, 2017 and ending on (and including) April 1, 2026, in an amount equal to 4% of the total number of shares of capital stock outstanding on March 31 of the preceding fiscal year, or a lesser number of shares as determined by the Company’s board of directors. On April 1, 2018, the number of common shares authorized for issuance increased automatically by 2.4 million shares in accordance with the evergreen provision of the 2016 Plan. As of March 31, 2019, a total of 2.1 million common shares were available for future issuance under the 2016 Plan.

The Company’s employees, directors, officers and consultants are eligible to receive non-qualified and incentive stock options, stock appreciation rights, restricted share awards, restricted stock unit awards, and other share awards under the 2016 Plan.

(B) Stock Options:

Each option will have an exercise price equal to the fair market value of the Company’s common shares on the date of grant. For grants of incentive stock options, if the grantee owns, or is deemed to own, 10% or more of the total voting power of the Company, then the exercise price shall be 110% of the fair market value of the Company’s common shares on the date of grant and the option will have a five-year contractual term. Options that are forfeited or expire are available for future grants.

Stock options granted under the 2016 Plan may provide option holders, if approved by the Company’s board of directors, the right to exercise their options prior to vesting. In the event that an option holder exercises the unvested portion of any option, such unvested portion will be subject to a repurchase option held by the Company at the lower of (1) the fair market value of its common shares on the date of repurchase and (2) the exercise price of the options. Any common shares underlying such unvested portion will continue to vest in accordance with the original vesting schedule of the option.

A summary of stock option activity and data under the Company’s 2016 Plan for the periods presented is as follows:



	Number of Options		Weighted Average Exercise Price		Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in thousands)
Options outstanding at March 31, 2016	—		$	—	$	—	—	$	—
Granted	1,525,857		$	5.06	$	11.90
Options outstanding at March 31, 2017	1,525,857		$	5.06	$	11.90	9.52	$	10,255
Granted	2,338,116		$	12.50	$	8.35
Exercised	(15,195	)	$	2.38	$	12.75
Forfeited	(299,373	)	$	6.64	$	11.35
Options outstanding at March 31, 2018	3,549,405		$	9.84	$	9.60	9.02	$	40,557
Granted	2,246,410		$	21.36	$	14.10
Exercised	(154,494	)	$	8.41	$	10.29
Forfeited	(244,856	)	$	14.59	$	11.05
Options outstanding at March 31, 2019	5,396,465		$	14.46	$	11.39	8.51	$	50,878
Options vested and expected to vest at March 31, 2019	5,396,465		$	14.46	$	11.39	8.51	$	50,878
Options exercisable at March 31, 2019	1,581,810		$	9.11	$	9.99	7.87	$	23,342

As of March 31, 2019, 2018 and 2017, there were 1,581,810, 502,361 and 28,406 vested options, respectively. Additional information regarding options is set forth below (in thousands, except per share data).



	Years Ended March 31,
	2019		2018		2017
Intrinsic value of options exercised	$	2,167	$	181	$	—
Grant date fair value of options vested	$	11,409	$	5,831	$	350
Weighted-average grant date fair value per share of options granted	$	14.10	$	8.35	$	11.90

A summary of restricted share award and restricted stock unit activity under the Company’s 2016 Plan for the periods presented is as follows:



	Number of shares		Weighted Average Grant Date Fair Value
Unvested balance at March 31, 2016	—		$	—
Granted	1,128,222		$	5.10
Unvested balance at March 31, 2017	1,128,222		$	5.10
Granted	579,111		$	14.10
Vested	(493,598	)	$	5.10
Unvested balance at March 31, 2018	1,213,735		$	9.39
Granted	29,700		$	17.28
Vested	(287,369	)	$	5.21
Unvested balance at March 31, 2019	956,066		$	10.90

The total fair value of restricted share awards vested during the years ended March 31, 2019 and 2018 was $1.4 million and $2.5 million, respectively. No restricted share awards vested during the year ended March 31, 2017. The total fair value of restricted stock units, or RSUs, vested during the year ended March 31, 2019 was $0.1 million. No RSUs vested during the years ended March 31, 2018 or 2017.

(D) Share-Based Compensation Expense:

Share-based compensation expense was as follows (in thousands):



	Years Ended March 31,
	2019		2018		2017
Share-based compensation expense recognized as:
R&D expenses	$	7,161	$	3,674	$	3,893
G&A expenses	11,535		7,909		4,824
Total	$	18,696	$	11,583	$	8,717

Share-based compensation expense is included in R&D and G&A expenses in the accompanying consolidated statements of operations consistent with the grantee’s salary. Share-based compensation expense presented in the table above includes share-based compensation expense allocated to the Company by RSL as described below in Note 9(E). Of the total share-based compensation expense, amounts recognized for options granted to non-employees were immaterial for all periods presented.

Total unrecognized share-based compensation expense was approximately $45.2 million as of March 31, 2019 and is expected to be recognized over a weighted-average period of approximately 2.83 years.

The Company estimated the fair value of each option on the date of grant using the Black-Scholes closed-form option-pricing model applying the weighted average assumptions in the following table:



	Years Ended March 31,
	2019		2018		2017
Expected common share price volatility	71.6	%	74.4	%	75.5	%
Expected risk free interest rate	2.78	%	2.04	%	1.57	%
Expected term, in years	6.23		6.22		6.35
Expected dividend yield	—	%	—	%	—	%

(E) Share-Based Compensation Expense for Related Parties:

(1) Share-Based Compensation Expense Allocated to the Company by RSL:

In relation to the RSL common share awards and RSL options issued by RSL to RSL, RSI, RSG and the Company’s employees, the Company recorded share-based compensation expense of $0.6 million, $1.0 million and $4.9 million, respectively, for the years ended March 31, 2019, 2018 and 2017.

The RSL common share awards and RSL options granted by RSL to RSL, RSI, RSG and the Company’s employees are valued by RSL at fair value on the date of grant and that fair value is recognized as share-based compensation expense over the requisite service period. Significant judgment and estimates were used by RSL to estimate the fair value of these awards and options, as they are not publicly traded. RSL common share awards and RSL options are subject to specified vesting schedules and requirements (a mix of time-based and performance- based events). The fair value is based on various corporate event-based considerations, including targets for RSL’s post-IPO market capitalization and future financing events). The fair value of each RSL option is estimated on the date of grant using the Black-Scholes closed-form option-pricing model.

Share-based compensation expense has been and will continue to be allocated to the Company over the requisite service period over which these RSL common share awards and RSL options are expected to vest and based upon the relative percentage of time utilized by RSL, RSI and RSG employees on Company matters.

(2) RSL RSUs:

The Company’s Principal Executive Officer was granted 66,845 RSL RSUs during the year ended March 31, 2017. These RSUs will vest to the extent certain RSL performance criteria and certain RSL liquidity conditions are satisfied within specified years of the grant date, provided that the Company’s Principal Executive Officer has provided continued service to RSL or its subsidiaries through such date. As of March 31, 2019, the performance conditions had not been met and were deemed not probable of being met. For the years ended March 31, 2019, 2018 and 2017, the Company recorded no share-based compensation expense related to these RSL RSUs. As of March 31, 2019, there was $0.9 million of unrecognized compensation expense related to unvested RSL RSUs. The Company will recognize this share-based compensation expense upon achievement of the performance and market conditions through the requisite service period.

Fair Value Measurements

12 Months Ended

Mar. 31, 2019

Fair Value Disclosures [Abstract]

Fair Value Measurements

As of March 31, 2019, assets measured at fair value on a recurring basis consisted of money market funds and commercial paper, which are included in cash and cash equivalents in the consolidated balance sheet. There were no assets measured at fair value as of March 31, 2018. The following table summarizes these assets (in thousands):



	As of March 31, 2019
	Level 1		Level 2		Level 3		Total Fair Value
Assets:
Money market funds	$	83	$	—	$	—	$	83
Commercial paper	—		126,050		—		126,050
Total assets	$	83	$	126,050	$	—	$	126,133

Money market funds are included in Level 1 of the fair value hierarchy and are valued at the closing price reported by an actively traded exchange. Commercial paper is included in Level 2 of the fair value hierarchy and is valued using third-party pricing services. The pricing services utilize industry standard valuation models, including both income and market-based approaches, for which all significant inputs are observable, either directly or indirectly.

There were no liabilities measured at fair value on a recurring basis as of March 31, 2019 or 2018. There were no transfers of assets or liabilities between the fair value hierarchy levels that occurred during the years ended March 31, 2019, 2018 or 2017.

Before expiration on April 30, 2017, the Company measured the warrant liability associated with the license agreement with Takeda at fair value based on significant inputs not observable in the market, which caused it to be classified as a Level 3 measurement within the fair value hierarchy. The valuation of the warrant liability used assumptions and estimates the Company believed would be made by a market participant in making the same valuation. The Company assessed these assumptions and estimates on an ongoing basis through the expiration of the Takeda warrant as additional data impacting the assumptions and estimates was obtained. Changes in the fair value of the warrant liability related to updated assumptions and estimates were recognized as other (expense) income in the consolidated statements of operations.

The fair value of the Takeda warrant liability as of March 31, 2017 was calculated using the following significant unobservable inputs:



Input	Range or Point Estimate Used
Projected time frame to an equity financing	April 2017
Probability of a successful equity financing	2.0	%
Annualized equity volatility	73.4	%
Risk-free interest rate	0.74	%

The changes in fair value of the Takeda warrant liability during the years ended March 31, 2018 and 2017 were as follows (in thousands):



Balance at March 31, 2016	$	—
Fair value of the Takeda warrant liability issued	5,377
Changes in the fair value of the Takeda warrant liability, included in net loss	27,518
Settlements	(32,843		)
Balance at March 31, 2017	52
Fair value of the warrant liability issued	—
Changes in the fair value of the warrant liability, included in net loss	—
Settlements	(52		)
Balance at March 31, 2018	$	—

For the year ended March 31, 2018, changes in the carrying value of the Takeda warrant liability resulted from settlements related to the fair value of the Takeda warrant automatically exercised.

For the year ended March 31, 2017, changes in the carrying value of the Takeda warrant liability resulted from settlements related to the fair value of the Takeda warrant exercised, partially offset by changes in the fair value of the Takeda warrant liability primarily due to the changes in the estimated probabilities of future financing events, change in the enterprise value of the Company, automatic exercise of the Takeda warrant and the passage of time.

- 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

Commitments and Contingencies

12 Months Ended

Mar. 31, 2019

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

(A) Operating Leases:

The Company leases 40,232 square feet of office space located in Brisbane, California, pursuant to a lease agreement, as amended, that expires in May of 2026. The Company has the option to extend the lease term for an additional seven years. The lease agreement, as amended, required the Company to deliver an irrevocable standby letter of credit in the amount of $0.5 million to the landlord, the amount of which is subject to reduction to approximately $0.2 million if certain conditions are met, for the duration of the lease.

Future operating lease obligations (excluding the optional lease renewal term) as of March 31, 2019 are as follows (in thousands):



Years Ended March 31,	Operating Leases

2020	$	2,006
2021	2,065
2022	2,128
2023	2,200
2024	2,339
Thereafter	5,307
Total minimum operating lease payments	$	16,045

Rent expense for the years ended March 31, 2019, 2018 and 2017 was $2.1 million, $0.9 million and $0.3 million, respectively.

(B) Indemnification Agreements:

The Company has agreed to indemnify its officers and directors for certain events or occurrences, subject to certain limits, while the officer or director was serving at the Company’s request in such capacity. The maximum amount of potential future indemnification liability is unlimited; however, the Company holds directors’ and officers’ liability insurance which limits the Company’s exposure and may enable it to recover a portion of any future amounts paid. In the normal course of business, the Company also enters into contracts and agreements with service providers and other parties with which it conducts business that contain indemnification provisions pursuant to which the Company has agreed to indemnify the party against certain types of third-party claims. The Company has not experienced any material losses related to these indemnification obligations, and no material claims with respect thereto were outstanding. The Company does not expect significant claims related to these indemnification obligations and, consequently, concluded that the fair value of these obligations is negligible, and no related reserves were established.

In the normal course of business, the Company enters into agreements with contract service providers to assist in the performance of its R&D activities. Expenditures to contract research organizations and contract manufacturing organizations represent significant costs in the Company’s clinical development of its product candidates. Subject to required notice periods and the Company’s obligations under binding purchase orders, the Company can elect to discontinue the work under these agreements at any time. The Company expects to enter into additional collaborative research, contract research, manufacturing, and supplier agreements in the future, which may require upfront payments and long-term commitments of capital resources.

(D) Legal Contingencies:

The Company may be, from time to time, a party to various disputes and claims arising from normal business activities. The Company accrues for loss contingencies when available information indicates that it is probable that a liability has been incurred and the amount of such liability can be reasonably estimated. In the cases where the Company believes that a reasonably possible loss exists, the Company discloses the facts and circumstances of the loss contingency, including an estimable range, if possible. The Company is currently not involved in any material legal proceedings.

(E) Others:

The Company has entered into commitments under its license agreement with Takeda (See Note 3) and financing arrangements with NovaQuest and Hercules (See Note 5).

Selected Quarterly Data (Unaudited)

12 Months Ended

Mar. 31, 2019

Quarterly Financial Information Disclosure [Abstract]

Selected Quarterly Data (Unaudited)

Selected Quarterly Financial Data (Unaudited)

The following table presents selected unaudited quarterly financial data of the Company for the years ended March 31, 2019 and 2018. The unaudited quarterly financial data is prepared on the same basis as the audited consolidated financial statements, and in the opinion of management, includes all recurring adjustments necessary for a fair statement of such information. The Company’s operating results for any quarter are not necessarily indicative of the operating results for any future quarters or a full year. The net loss per common share amounts for the quarterly periods have been computed separately. Therefore, the sum of quarterly net loss per common share amounts may not equal annual net loss per common share amounts.



	First Quarter Ended			Second Quarter Ended			Third Quarter Ended			Fourth Quarter Ended			First Quarter Ended			Second Quarter Ended			Third Quarter Ended			Fourth Quarter Ended
	June 30,			September 30,			December 31,			March 31,			June 30,			September 30,			December 31,			March 31,
	2018			2018			2018			2019			2017			2017			2017			2018
Total operating expenses	$	60,083		$	64,123		$	69,120		$	71,500		$	21,890		$	30,311		$	41,515		$	47,347
Net loss	$	(62,134	)	$	(65,770	)	$	(70,633	)	$	(75,014	)	$	(23,317	)	$	(29,908	)	$	(41,777	)	$	(48,253	)
Net loss per share attributable to common shareholders - basic and diluted	$	(0.98	)	$	(0.99	)	$	(1.04	)	$	(1.07	)	$	(0.39	)	$	(0.50	)	$	(0.70	)	$	(0.81	)

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Mar. 31, 2019

Accounting Policies [Abstract]

Basis of Accounting

The accompanying consolidated financial statements have been prepared in accordance with United States, or U.S., generally accepted accounting principles, or U.S. GAAP.

Use of Estimates

Concentrations of Credit Risk

Cash, Cash Equivalents and Restricted Cash

Property and Equipment

Operating Leases

Certain lease agreements also require the Company to make additional payments for taxes, insurance, and other operating expenses incurred during the lease period, which are expensed as incurred.

Debt Issuance Costs and Debt Discount

Contingencies

Research and Development Expenses

Share-based Compensation

he Company estimates the grant date fair value, and the resulting share-based compensation expense, using the Black-Scholes option-pricing model, which requires the use of highly subjective assumptions. These assumptions include:


•	Expected Term. The expected term represents the period that the Company’s share-based awards are expected to be outstanding and is determined using the simplified method in accordance with the Securities and Exchange Commission, or SEC, Staff Accounting Bulletin, or SAB, No. 107 and No. 110 (based on the mid-point between the vesting date and the end of the contractual term).

•


•	Risk-Free Interest Rate. The risk-free interest rate is based on the interest rates paid on securities issued by the U.S. Treasury with a term approximating the expected life of the stock options.


•	Expected Dividend. The Company has never paid, and does not anticipate paying, cash dividends on its common shares. Therefore, the expected dividend yield was assumed to be zero.

Takeda Warrant Liability

Income Taxes

Net Loss Per Common Share

Fair Value Measurements


•	Level 1-Valuations are based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access.


•	Level 2-Valuations are based on quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active and models for which all significant inputs are observable, either directly or indirectly.


•	Level 3-Valuations are based on inputs that are unobservable (supported by little or no market activity) and significant to the overall fair value measurement.

Foreign Currency

Recently Issued Accounting Pronouncements

(1) Leases:

(2) Others:

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Mar. 31, 2019

Accounting Policies [Abstract]

Schedule of Cash, Cash Equivalents, and Restricted Cash

Cash as reported in the consolidated statements of cash flows includes the aggregate amounts of cash, cash equivalents, and restricted cash, and consists of the following (in thousands):



	March 31,
	2019		2018		2017
Cash and cash equivalents	$	156,074	$	108,624	$	180,838
Restricted cash⁽¹⁾	1,125		—		—
Total cash, cash equivalents and restricted cash	$	157,199	$	108,624	$	180,838

⁽¹⁾ Included in other assets on the consolidated balance sheets.

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share

As of March 31, 2019, 2018 and 2017, potentially dilutive securities were as follows:



	March 31,
	2019	2018	2017
Stock options	5,396,465	3,549,405	1,525,857
Restricted share awards (unvested)	916,679	1,198,735	1,128,222
Restricted stock units (unvested)	39,387	15,000	—
Warrants	73,710	73,710	—
Total	6,426,241	4,836,850	2,654,079

Financing Arrangements (Tables)

12 Months Ended

Mar. 31, 2019

Debt Disclosure [Abstract]

Schedule of Outstanding Debt Obligations

Outstanding debt obligations to NovaQuest are as follows (in thousands):



	March 31,
	2019			2018

Principal amount	$	60,000		$	6,000
Less: unamortized debt issuance costs	(756		)	(854		)
Loan payables less unamortized debt issuance costs	59,244			5,146
Less: current maturities	—			—
Long-term debt, net of current maturities and unamortized debt issuance costs	$	59,244		$	5,146

Outstanding debt obligations to Hercules are as follows (in thousands):



	March 31,
	2019			2018

Principal amount	$	40,000		$	40,000
End of term charge	2,620			2,620
Less: unamortized debt discount and issuance costs	(2,482		)	(4,142		)
Loan payables less unamortized debt discount and issuance costs	40,138			38,478
Less: current maturities	(6,142		)	—
Long-term debt, net of current maturities and unamortized debt discount and issuance costs	$	33,996		$	38,478

Key Assumptions used to Measure Value of Warrant

The Company estimated the fair value of the Warrants using the Black-Scholes model based on the following key assumptions:



	Tranche 1	Tranche 2

Exercise price	$15.06	$18.82
Common share price on date of issuance	$14.39	$18.96
Volatility	73.2%	72.3%
Risk-free interest rate	2.15%	2.78%
Expected dividend yield	—%	—%
Contractual term (in years)	7.00	7.00

The fair value of the Takeda warrant liability as of March 31, 2017 was calculated using the following significant unobservable inputs:



Input	Range or Point Estimate Used
Projected time frame to an equity financing	April 2017
Probability of a successful equity financing	2.0	%
Annualized equity volatility	73.4	%
Risk-free interest rate	0.74	%

Schedule of Maturities of Long-term Debt

Annual maturities of debt outstanding as of March 31, 2019 are as follows (in thousands):



Years Ended March 31,

2020	$	6,142
2021	28,854
2022	32,696
2023	18,462
2024	13,846
Thereafter	—
Total	$	100,000

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28541-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21521-112644

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21538-112644

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

Income Taxes (Tables)

12 Months Ended

Mar. 31, 2019

Income Tax Disclosure [Abstract]

Schedule of Loss Before Income Taxes and Related Tax Benefit

The loss before income taxes and the related tax expense (benefit) are as follows (in thousands):



	Years Ended March 31,
	2019			2018			2017
Loss before income taxes:
United States	$	(11,246	)	$	(7,229	)	$	(2,924	)
Switzerland	(247,445		)	(129,261		)	(29,745		)
Bermuda	(14,357		)	(6,513		)	(50,845		)
Other⁽¹⁾	(27		)	(39		)	—
Total loss before income taxes	$	(273,075	)	$	(143,042	)	$	(83,514	)

Current taxes:
United States	$	473		$	13		$	125
Switzerland	—			—			—
Bermuda	—			—			—
Other⁽¹⁾	3			(8		)	9
Total current tax expense	476			5			134
Deferred taxes:
United States	—			208			(208		)
Switzerland	—			—			—
Bermuda	—			—			—
Other⁽¹⁾	—			—			—
Total deferred tax expense (benefit)	—			208			(208		)
Total income tax expense (benefit)	$	476		$	213		$	(74	)


(1)	Primarily United States state and local, Ireland and United Kingdom activity.

Schedule of Effective Income Tax Reconciliation



	Years Ended March 31,
	2019					2018					2017
Income tax benefit at Bermuda statutory rate	$	—		—	%	$	—		—	%	$	—		—	%
Foreign rate differential⁽²⁾	(31,252		)	11.44		(14,802		)	10.35		(7,592		)	9.09
Valuation allowance	32,335			(11.83	)	13,966			(9.77	)	7,378			(8.83	)
Tax reform	—			—		1,049			(0.73	)	—			—
Other	(607		)	0.22		—			—		140			(0.17	)
Total income tax expense (benefit)	$	476		(0.17	)%	$	213		(0.15	)%	$	(74	)	0.09	%


(2)	Primarily related to current tax on United States operations including permanent and temporary differences (e.g. research and development credits, etc.) as well as operations in Switzerland and the United Kingdom at rates different than the Bermuda rate.

Schedule of Deferred Taxes

Significant components of the deferred tax assets and liabilities as of March 31, 2019 and 2018 are as follows (in thousands):



	March 31,
	2019			2018
Deferred tax assets:
Research tax credits	$	7,224		$	2,948
Net operating losses⁽³⁾	38,194			16,045
Share-based compensation	6,106			2,380
Intangibles⁽⁴⁾	38,673			—
Other	2,539			169
Subtotal	92,736			21,542
Valuation allowance	(92,330		)	(21,367		)

Deferred tax liabilities:
Depreciation	(406		)	(175		)
Total deferred tax assets	$	—		$	—

(3)

Share-Based Compensation (Tables)

12 Months Ended

Mar. 31, 2019

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of Stock Option Activity

A summary of stock option activity and data under the Company’s 2016 Plan for the periods presented is as follows:



	Number of Options		Weighted Average Exercise Price		Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in thousands)
Options outstanding at March 31, 2016	—		$	—	$	—	—	$	—
Granted	1,525,857		$	5.06	$	11.90
Options outstanding at March 31, 2017	1,525,857		$	5.06	$	11.90	9.52	$	10,255
Granted	2,338,116		$	12.50	$	8.35
Exercised	(15,195	)	$	2.38	$	12.75
Forfeited	(299,373	)	$	6.64	$	11.35
Options outstanding at March 31, 2018	3,549,405		$	9.84	$	9.60	9.02	$	40,557
Granted	2,246,410		$	21.36	$	14.10
Exercised	(154,494	)	$	8.41	$	10.29
Forfeited	(244,856	)	$	14.59	$	11.05
Options outstanding at March 31, 2019	5,396,465		$	14.46	$	11.39	8.51	$	50,878
Options vested and expected to vest at March 31, 2019	5,396,465		$	14.46	$	11.39	8.51	$	50,878
Options exercisable at March 31, 2019	1,581,810		$	9.11	$	9.99	7.87	$	23,342

Additional information regarding options is set forth below (in thousands, except per share data).



	Years Ended March 31,
	2019		2018		2017
Intrinsic value of options exercised	$	2,167	$	181	$	—
Grant date fair value of options vested	$	11,409	$	5,831	$	350
Weighted-average grant date fair value per share of options granted	$	14.10	$	8.35	$	11.90

Summary of Restricted Share Awards and Restricted Stock Units Activity

A summary of restricted share award and restricted stock unit activity under the Company’s 2016 Plan for the periods presented is as follows:



	Number of shares		Weighted Average Grant Date Fair Value
Unvested balance at March 31, 2016	—		$	—
Granted	1,128,222		$	5.10
Unvested balance at March 31, 2017	1,128,222		$	5.10
Granted	579,111		$	14.10
Vested	(493,598	)	$	5.10
Unvested balance at March 31, 2018	1,213,735		$	9.39
Granted	29,700		$	17.28
Vested	(287,369	)	$	5.21
Unvested balance at March 31, 2019	956,066		$	10.90

Schedule of Share-based Compensation Expense

Share-based compensation expense was as follows (in thousands):



	Years Ended March 31,
	2019		2018		2017
Share-based compensation expense recognized as:
R&D expenses	$	7,161	$	3,674	$	3,893
G&A expenses	11,535		7,909		4,824
Total	$	18,696	$	11,583	$	8,717

Schedule of Weighted Average Fair Value Assumptions

The Company estimated the fair value of each option on the date of grant using the Black-Scholes closed-form option-pricing model applying the weighted average assumptions in the following table:



	Years Ended March 31,
	2019		2018		2017
Expected common share price volatility	71.6	%	74.4	%	75.5	%
Expected risk free interest rate	2.78	%	2.04	%	1.57	%
Expected term, in years	6.23		6.22		6.35
Expected dividend yield	—	%	—	%	—	%

Fair Value Measurements (Tables)

12 Months Ended

Mar. 31, 2019

Fair Value Disclosures [Abstract]

Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis

There were no assets measured at fair value as of March 31, 2018. The following table summarizes these assets (in thousands):



	As of March 31, 2019
	Level 1		Level 2		Level 3		Total Fair Value
Assets:
Money market funds	$	83	$	—	$	—	$	83
Commercial paper	—		126,050		—		126,050
Total assets	$	83	$	126,050	$	—	$	126,133

Schedule of Significant Unobservable Inputs

The Company estimated the fair value of the Warrants using the Black-Scholes model based on the following key assumptions:



	Tranche 1	Tranche 2

Exercise price	$15.06	$18.82
Common share price on date of issuance	$14.39	$18.96
Volatility	73.2%	72.3%
Risk-free interest rate	2.15%	2.78%
Expected dividend yield	—%	—%
Contractual term (in years)	7.00	7.00

The fair value of the Takeda warrant liability as of March 31, 2017 was calculated using the following significant unobservable inputs:



Input	Range or Point Estimate Used
Projected time frame to an equity financing	April 2017
Probability of a successful equity financing	2.0	%
Annualized equity volatility	73.4	%
Risk-free interest rate	0.74	%

Schedule of Changes in Fair Value of Level 3 Warrant Liability

The changes in fair value of the Takeda warrant liability during the years ended March 31, 2018 and 2017 were as follows (in thousands):



Balance at March 31, 2016	$	—
Fair value of the Takeda warrant liability issued	5,377
Changes in the fair value of the Takeda warrant liability, included in net loss	27,518
Settlements	(32,843		)
Balance at March 31, 2017	52
Fair value of the warrant liability issued	—
Changes in the fair value of the warrant liability, included in net loss	—
Settlements	(52		)
Balance at March 31, 2018	$	—

Selected Quarterly Data (Unaudited) (Tables)

12 Months Ended

Mar. 31, 2019

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Data



	First Quarter Ended			Second Quarter Ended			Third Quarter Ended			Fourth Quarter Ended			First Quarter Ended			Second Quarter Ended			Third Quarter Ended			Fourth Quarter Ended
	June 30,			September 30,			December 31,			March 31,			June 30,			September 30,			December 31,			March 31,
	2018			2018			2018			2019			2017			2017			2017			2018
Total operating expenses	$	60,083		$	64,123		$	69,120		$	71,500		$	21,890		$	30,311		$	41,515		$	47,347
Net loss	$	(62,134	)	$	(65,770	)	$	(70,633	)	$	(75,014	)	$	(23,317	)	$	(29,908	)	$	(41,777	)	$	(48,253	)
Net loss per share attributable to common shareholders - basic and diluted	$	(0.98	)	$	(0.99	)	$	(1.04	)	$	(1.07	)	$	(0.39	)	$	(0.50	)	$	(0.70	)	$	(0.81	)

Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2019 USD ($) bank	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2019 USD ($) bank segment	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Apr. 01, 2019 USD ($)	Apr. 01, 2018 USD ($)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of operating segments \| segment									1
Number of reporting segments \| segment									1
Net loss	$ (75,014)	$ (70,633)	$ (65,770)	$ (62,134)	$ (48,253)	$ (41,777)	$ (29,908)	$ (23,317)	$ (273,551)	$ (143,255)	$ (83,440)
Net cash used in operating activities									$ (224,088)	$ (117,255)	$ (18,215)
Number of banking institutions \| bank	3								3
Expected dividend yield									0.00%	0.00%	0.00%
Intangible deferred tax assets	$ 38,673				0				$ 38,673	$ 0
Deferred tax assets valuation allowance	$ 92,330				$ 21,367				$ 92,330	$ 21,367
Minimum
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Estimated useful lives of property and equipment									3 years
Maximum
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Estimated useful lives of property and equipment									7 years
Accounting Standards Update 2016-02 \| Scenario, Forecast \| Minimum
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
ROU asset												$ 9,000
Lease liability												10,000
Accounting Standards Update 2016-02 \| Scenario, Forecast \| Maximum
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
ROU asset												10,000
Lease liability												$ 11,000
Accounting Standards Update 2016-16
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Intangible deferred tax assets													$ 38,700
Deferred tax assets valuation allowance													$ 38,700

Summary of Significant Accounting Policies - Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Accounting Policies [Abstract]
Cash and cash equivalents	$ 156,074	$ 108,624	$ 180,838
Restricted cash	1,125	0	0
Total cash, cash equivalents and restricted cash	$ 157,199	$ 108,624	$ 180,838	$ 0

Summary of Significant Accounting Policies - Schedule of Antidilutive Securities (Details) - shares	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	6,426,241	4,836,850	2,654,079
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	5,396,465	3,549,405	1,525,857
Restricted share awards (unvested)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	916,679	1,198,735	1,128,222
Restricted stock units (unvested)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	39,387	15,000	0
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	73,710	73,710	0

License Agreement - Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
	Apr. 29, 2016	Mar. 31, 2019	Mar. 31, 2018	Apr. 30, 2017	Mar. 31, 2017
Other Liabilities Disclosure [Abstract]
Shares issued to Takeda under the Takeda license agreement (in shares)	5,077,001
Period for which royalties are required to be paid after first commercial sale	10 years
Ownership percentage to which holders are entitled too	12.00%
Shares issued to settle the warrant liability (in shares)			4,432	2,343,624	2,339,192
Acquisition of in-process research and development	$ 13,100	$ 0	$ 0		$ 13,117
Research and development expense, fair value of shares issued	7,700				$ 7,740
Takeda warrant liability	$ 5,400

Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Mar. 31, 2018
Payables and Accruals [Abstract]
Accrued R&D expenses	$ 46,947	$ 25,988
Accrued compensation-related expenses	5,024	2,792
Accrued professional service fees	370	566
Accrued other expenses	1,273	919
Total accrued expenses	$ 53,614	$ 30,265

(Narrative) (Details) - USD ($)	1 Months Ended		12 Months Ended
(Narrative) (Details) - USD ($)	Dec. 31, 2018	Oct. 31, 2017	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Debt Instrument [Line Items]
Equity commitment, purchase price as a percentage of share price		105.00%
Equity commitment, number consecutive trading days used for measuring share price		5 days
Equity commitment related to note issuance		$ 20,000,000
Equity commitment related to note issuance in current year		$ 10,000,000
Payments of debt administrative fee			$ 300,000	$ 0	$ 0
Common Shares
Debt Instrument [Line Items]
Warrants exercisable as a percentage of principal amount of loan		3.00%
Private Placement
Debt Instrument [Line Items]
Shares purchased (in shares)		138,361
Shares purchased		$ 2,000,000
Line of Credit \| NovaQuest Securities Purchase Agreement
Debt Instrument [Line Items]
Maximum borrowing commitment		60,000,000
Equity commitment		20,000,000
Minimum borrowing commitment		30,000,000
Debt issued	$ 54,000,000	$ 6,000,000
Interest rate		15.00%
Quarterly interest rate		5.00%
Deferred interest rate		10.00%
Default interest rate		5.00%
Financing expenses		$ 1,000,000
Amortized deferred financing costs			400,000	200,000
Term Loan \| Hercules Loan Agreement
Debt Instrument [Line Items]
Maximum borrowing commitment		$ 40,000,000
Interest rate		8.25%
Default interest rate		5.00%
Amortized deferred financing costs			$ 1,700,000	500,000
Principal amount funded		$ 25,000,000		$ 15,000,000
Current interest rate			9.50%
End of term charge		6.55%
Term Loan \| Hercules Loan Agreement \| Prime Rate
Debt Instrument [Line Items]
Variable interest rate		4.00%
Tranche 1 \| Common Shares
Debt Instrument [Line Items]
Number of securities exercisable by warrant (in shares)		49,800
Exercise price of warrants (in USD per share)		$ 15.06
Fair value of warrant on date of issuance		$ 500,000
Tranche 1 \| Term Loan \| Hercules Loan Agreement
Debt Instrument [Line Items]
Financing expenses		1,300,000
Discount		$ 2,100,000
Tranche 2 \| Common Shares
Debt Instrument [Line Items]
Number of securities exercisable by warrant (in shares)				23,910
Exercise price of warrants (in USD per share)				$ 18.82
Fair value of warrant on date of issuance				$ 300,000
Tranche 2 \| Term Loan \| Hercules Loan Agreement
Debt Instrument [Line Items]
Discount				$ 1,300,000
NovaQuest \| Private Placement
Debt Instrument [Line Items]
Shares purchased (in shares)	1,082,977
Shares purchased	$ 18,000,000
NovaQuest \| Private Placement
Debt Instrument [Line Items]
Shares purchased (in shares)	1,203,307
Shares purchased	$ 20,000,000

(Outstanding Debt Obligations) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Mar. 31, 2018
Debt Instrument [Line Items]
Principal amount	$ 100,000
Less: current maturities	(6,142)	$ 0
Long-term debt, net of current maturities and unamortized debt issuance costs	93,240	43,624
Line of Credit \| NovaQuest Securities Purchase Agreement
Debt Instrument [Line Items]
Principal amount	60,000	6,000
Less: unamortized debt issuance costs	(756)	(854)
Loan payables less unamortized debt issuance costs	59,244	5,146
Less: current maturities	0	0
Long-term debt, net of current maturities and unamortized debt issuance costs	59,244	5,146
Term Loan \| Hercules Loan Agreement
Debt Instrument [Line Items]
Principal amount	40,000	40,000
End of term charge	2,620	2,620
Less: unamortized debt issuance costs	(2,482)	(4,142)
Loan payables less unamortized debt issuance costs	40,138	38,478
Less: current maturities	(6,142)	0
Long-term debt, net of current maturities and unamortized debt issuance costs	$ 33,996	$ 38,478

(Key Assumptions Used to Value Warrants) (Details) - Common Shares	Mar. 31, 2018 year $ / shares	Oct. 31, 2017 year $ / shares
Tranche 1
Class of Warrant or Right [Line Items]
Exercise price (in USD per share)		$ 15.06
Common share price on date of issuance (in USD per share)		$ 14.39
Tranche 2
Class of Warrant or Right [Line Items]
Exercise price (in USD per share)	$ 18.82
Common share price on date of issuance (in USD per share)	$ 18.96
Volatility \| Tranche 1
Class of Warrant or Right [Line Items]
Measurement input		0.732
Volatility \| Tranche 2
Class of Warrant or Right [Line Items]
Measurement input	0.723
Risk-free interest rate \| Tranche 1
Class of Warrant or Right [Line Items]
Measurement input		0.0215
Risk-free interest rate \| Tranche 2
Class of Warrant or Right [Line Items]
Measurement input	0.0278
Expected dividend yield \| Tranche 1
Class of Warrant or Right [Line Items]
Measurement input		0.00
Expected dividend yield \| Tranche 2
Class of Warrant or Right [Line Items]
Measurement input	0.00
Contractual term (in years) \| Tranche 1
Class of Warrant or Right [Line Items]
Measurement input \| year		7.00
Contractual term (in years) \| Tranche 2
Class of Warrant or Right [Line Items]
Measurement input \| year	7.00

Financing Arrangements (Maturities of Long-term Debt) (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Debt Disclosure [Abstract]
2020	$ 6,142
2021	28,854
2022	32,696
2023	18,462
2024	13,846
Thereafter	0
Total	$ 100,000

Related Party Transactions - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Jun. 30, 2016	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
RSL and RSI \| Services Agreement \| RSL and RSI
Related Party Transaction [Line Items]
Allocated costs		$ 4.8	$ 7.7	$ 9.2
RSL \| Share-based Compensation Expense Allocated to Company \| RSL
Related Party Transaction [Line Items]
Allocated costs		$ 0.6	$ 1.0	$ 4.9
RSL \| Option Agreement \| RSL
Related Party Transaction [Line Items]
Option agreement, term	2 years
Option agreement, purchase price as a percentage of payments made by RSL	110.00%

Shareholders' Equity (Deficit) - Narrative (Details) $ / shares in Units, $ in Millions			1 Months Ended					2 Months Ended	12 Months Ended
	Nov. 01, 2016 USD ($) $ / shares shares	Oct. 18, 2016	Apr. 30, 2019 USD ($) shares	Dec. 31, 2018 USD ($) shares	Apr. 30, 2018 USD ($) $ / shares shares	Oct. 31, 2017 USD ($) $ / shares shares	Apr. 30, 2017 shares	Aug. 31, 2018 USD ($) shares	Mar. 31, 2019 USD ($) $ / shares shares	Mar. 31, 2018 $ / shares shares	Apr. 30, 2017 shares	Mar. 31, 2017 shares	Jul. 31, 2018 $ / shares	Feb. 02, 2016 class
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of classes of stock \| class														1
Common shares authorized (in shares)									564,111,242	564,111,242
Common shares par value (in USD per share) \| $ / shares									$ 0.000017727	$ 0.000017727
Reverse stock split ratio		0.5641
Shares issued to settle the warrant liability (in shares)										4,432	2,343,624	2,339,192
Options granted (in shares)									2,246,410	2,338,116		1,525,857
Initial Public Offering
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares sold (in shares)	14,500,000
Price of shares sold (in shares) \| $ / shares	$ 15.00
Gross proceeds from sale of shares \| $	$ 217.5
Net proceeds from sale of shares \| $	200.0
Underwriting discounts and commissions \| $	15.2
Offering costs \| $	$ 2.3
Shares issued to settle the warrant liability (in shares)												1,977,269
Public Equity Offering
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares sold (in shares)								3,533,399
Price of shares sold (in shares) \| $ / shares													$ 22.50
Net proceeds from sale of shares \| $								$ 74.4
Underwriter's Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares sold (in shares)								200,065
Private Placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares sold (in shares)						138,361
Net proceeds from sale of shares \| $						$ 2.0
Restricted Share Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued to settle the warrant liability (in shares)												153,846
Awards granted (in shares)												1,128,222
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued to settle the warrant liability (in shares)							32,500					208,077
Roivant Sciences, Ltd. \| Private Placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares sold (in shares)					1,110,015
Price of shares sold (in shares) \| $ / shares					$ 20.27
Gross proceeds from sale of shares \| $					$ 22.5
Cowen and Company, LLC \| Private Placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares sold (in shares)									3,970,129
Price of shares sold (in shares) \| $ / shares									$ 21.91
Net proceeds from sale of shares \| $									$ 84.1
Aggregate offering price \| $					$ 100.0
Remaining capacity in offering program \| $									$ 13.0
NovaQuest \| Private Placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares sold (in shares)				1,082,977
Net proceeds from sale of shares \| $				$ 18.0
NovaQuest \| Private Placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares sold (in shares)				1,203,307
Net proceeds from sale of shares \| $				$ 20.0
Tranche 1 \| Common Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities exercisable by warrant (in shares)						49,800
Exercise price of warrants (in USD per share) \| $ / shares						$ 15.06
Tranche 2 \| Common Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities exercisable by warrant (in shares)										23,910
Exercise price of warrants (in USD per share) \| $ / shares										$ 18.82
Subsequent Event \| Cowen and Company, LLC \| Private Placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares sold (in shares)			106,494
Net proceeds from sale of shares \| $			$ 2.5

Income Taxes - Loss Before Income Taxes and Related Tax Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Loss before income taxes:
Bermuda	$ (14,357)	$ (6,513)	$ (50,845)
Total loss before income taxes	(273,075)	(143,042)	(83,514)
Current taxes:
Bermuda	0	0	0
Total current tax expense	476	5	134
Deferred taxes:
Bermuda	0	0	0
Total deferred tax expense (benefit)	0	208	(208)
Total income tax expense (benefit)	476	213	(74)
United States
Loss before income taxes:
Foreign	(11,246)	(7,229)	(2,924)
Current taxes:
Foreign	473	13	125
Deferred taxes:
Foreign	0	208	(208)
Switzerland
Loss before income taxes:
Foreign	(247,445)	(129,261)	(29,745)
Current taxes:
Foreign	0	0	0
Deferred taxes:
Foreign	0	0	0
Other
Loss before income taxes:
Foreign	(27)	(39)	0
Current taxes:
Foreign	3	(8)	9
Deferred taxes:
Foreign	$ 0	$ 0	$ 0

Income Taxes - Effective Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Effective Income Tax Rate Reconciliation, Amount
Income tax benefit at Bermuda statutory rate	$ 0	$ 0	$ 0
Foreign rate differential	(31,252)	(14,802)	(7,592)
Valuation allowance	32,335	13,966	7,378
Tax reform	0	1,049	0
Other	(607)	0	140
Total income tax expense (benefit)	$ 476	$ 213	$ (74)
Effective Income Tax Rate Reconciliation, Percent
Income tax benefit at Bermuda statutory rate	0.00%	0.00%	0.00%
Foreign rate differential	11.44%	10.35%	9.09%
Valuation allowance	(11.83%)	(9.77%)	(8.83%)
Tax reform	0.00%	(0.73%)	0.00%
Other	0.22%	0.00%	(0.17%)
Total income tax expense (benefit)	(0.17%)	(0.15%)	0.09%

Income Taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Income Taxes - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Effective income tax rate	(0.17%)	(0.15%)	0.09%
Operating Loss Carryforwards [Line Items]
Deferred tax assets valuation allowance	$ 92,330	$ 21,367
Switzerland
Operating Loss Carryforwards [Line Items]
Net operating losses	376,200
Ireland
Operating Loss Carryforwards [Line Items]
Net operating losses	32
United Kingdom
Operating Loss Carryforwards [Line Items]
Net operating losses	14,400
United States \| Research and Development Credit Carryforward
Operating Loss Carryforwards [Line Items]
Credit carryforwards	$ 7,200

Income Taxes - Deferred Taxes (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Apr. 01, 2018	Mar. 31, 2018
Deferred tax assets:
Research tax credits	$ 7,224		$ 2,948
Net operating loss	38,194		16,045
Share-based compensation	6,106		2,380
Intangibles	38,673		0
Other	2,539		169
Subtotal	92,736		21,542
Valuation allowance	(92,330)		(21,367)
Deferred tax liabilities:
Depreciation	(406)		(175)
Total deferred tax assets	$ 0		$ 0
Accounting Standards Update 2016-16
Deferred tax assets:
Intangibles		$ 38,700
Valuation allowance		$ (38,700)

Share-Based Compensation - Narrative (Details) - USD ($)		3 Months Ended	12 Months Ended
	Apr. 01, 2018	Mar. 31, 2019	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested options (in shares)		1,581,810	1,581,810	502,361	28,406
Unrecognized share-based compensation		$ 45,200,000	$ 45,200,000
Unrecognized share-based compensation, period for recognition			2 years 304 days
RSL Employees \| Share-based Compensation Expense Allocated to Company
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated costs			$ 600,000	$ 1,000,000	$ 4,900,000
Stock options \| Principal Owner
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Threshold percentage of total voting power of the company		10.00%	10.00%
Exercise price as a percentage of fair value		110.00%	110.00%
Contractual term			5 years
Restricted Share Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vested during period (in shares)			$ 1,400,000	2,500,000	$ 0
Awards granted (in shares)					1,128,222
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vested during period (in shares)			100,000	0	$ 0
Restricted Stock Units \| Principal Executive Officer \| RSL \| RSL RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated costs		$ 0		$ 0	$ 0
Awards granted (in shares)					66,845
Unrecognized compensation cost related to restricted stock units		$ 900,000	$ 900,000
2016 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for grant (in shares)		2,100,000	2,100,000			4,500,000
Common shares reserved for grant, annual percentage increase						4.00%
Increase in common shares reserved for grant (in shares)	2,400,000

Share-Based Compensation - Summary of Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Number of Options
Beginning balance (in shares)	3,549,405	1,525,857	0
Granted (in shares)	2,246,410	2,338,116	1,525,857
Exercised (in shares)	(154,494)	(15,195)
Forfeited (in shares)	(244,856)	(299,373)
Ending balance (in shares)	5,396,465	3,549,405	1,525,857	0
Weighted Average Exercise Price
Beginning balance (in USD per share)	$ 9.84	$ 5.06	$ 0.00
Granted (in USD per share)	21.36	12.50	5.06
Exercised (in USD per share)	8.41	2.38
Forfeited (in USD per share)	14.59	6.64
Ending balance (in USD per share)	14.46	9.84	5.06	$ 0.00
Weighted Average Grant Date Fair Value
Beginning balance (in USD per share)	9.60	11.90	0.00
Granted (in USD per share)	14.10	8.35	11.90
Exercised (in USD per share)	10.29	12.75
Forfeited (in USD per share)	11.05	11.35
Ending balance (in USD per share)	$ 11.39	$ 9.60	$ 11.90	$ 0.00
Options Vested and Expected to Vest
Number of Options (in shares)	5,396,465
Weighted Average Exercise Price (in USD per share)	$ 14.46
Weighted Average Grant Date Fair Value (in USD per share)	$ 11.39
Weighted Average Remaining Contractual Life (in years)	8 years 187 days
Aggregate Intrinsic Value (in thousands)	$ 50,878
Additional Information
Options outstanding, Weighted Average Remaining Contractual Life	8 years 187 days	9 years 7 days	9 years 190 days	0 years
Options outstanding, Aggregate Intrinsic Value	$ 50,878	$ 40,557	$ 10,255	$ 0
Options exercisable, Number of Options (in shares)	1,581,810	502,361	28,406
Options exercisable, Weighted Average Exercise Price (in USD per share)	$ 9.11
Options exercisable, Weighted Average Grant Date Fair Value (in USD per share)	$ 9.99
Options exercisable, Weighted Average Remaining Contractual Life	7 years 318 days
Options exercisable, Aggregate Intrinsic Value	$ 23,342

Share-Based Compensation - Additional Information for Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Intrinsic value of options exercised	$ 2,167	$ 181	$ 0
Grant date fair value of options vested	$ 11,409	$ 5,831	$ 350
Weighted-average grant date fair value per share of options granted (in USD per share)	$ 14.10	$ 8.35	$ 11.90

Share-Based Compensation - Restricted Share Awards and Restricted Stock Units Activity (Details) - Restricted Stock and Restricted Stock Units - $ / shares	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Number of shares
Beginning balance (in shares)	1,213,735	1,128,222	0
Granted (in shares)	29,700	579,111	1,128,222
Vested (in shares)	(287,369)	(493,598)
Ending balance (in shares)	956,066	1,213,735	1,128,222
Weighted Average Grant Date Fair Value
Beginning balance (in USD per share)	$ 9.39	$ 5.10	$ 0.00
Granted (in USD per share)	5.21	5.10
Vested (in USD per share)	17.28	14.10	5.10
Ending balance (in USD per share)	$ 10.90	$ 9.39	$ 5.10

Share-Based Compensation - Share-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	$ 18,696	$ 11,583	$ 8,717
R&D expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	7,161	3,674	3,893
G&A expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	$ 11,535	$ 7,909	$ 4,824

Share-Based Compensation - Schedule of Fair Value Assumptions for Stock Options (Details)	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected common share price volatility	71.60%	74.40%	75.50%
Expected risk free interest rate	2.78%	2.04%	1.57%
Expected term, in years	6 years 84 days	6 years 80 days	6 years 128 days
Expected dividend yield	0.00%	0.00%	0.00%

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	$ 126,133
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	83
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	126,050
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	83
Money market funds \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	83
Money market funds \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0
Money market funds \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	126,050
Commercial paper \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0
Commercial paper \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	126,050
Commercial paper \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 0

Fair Value Measurements - Schedule of Significant Unobservable Inputs (Details) - Fair Value, Measurements, Recurring - Warrant Liability - Level 3	Mar. 31, 2019
Probability of a successful equity financing
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.020
Annualized equity volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.734
Risk-free interest rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.0074

Fair Value Measurements - Schedule of Changes in Fair Value of Liabilities (Details) - Warrant Liability - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 52	$ 0
Fair value of the warrant liability issued	0	5,377
Changes in the fair value of the warrant liability, included in net loss	0	27,518
Settlements	(52)	(32,843)
Ending balance	$ 0	$ 52

Commitments and Contingencies - Contractual Obligations (Details) $ in Thousands	12 Months Ended
	Mar. 31, 2019 USD ($) ft²	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)
Property Subject to or Available for Operating Lease [Line Items]
2020	$ 2,006
2021	2,065
2022	2,128
2023	2,200
2024	2,339
Thereafter	5,307
Total minimum operating lease payments	16,045
Rent expense	$ 2,100	$ 900	$ 300
Brisbane, California Office Space
Property Subject to or Available for Operating Lease [Line Items]
Area leased (in sq ft) \| ft²	40,232
Extension term	7 years
Letter of credit	$ 500
Reduced letter of credit if conditions met	$ 200

Selected Quarterly Data (Unaudited) - Schedule of Quarterly Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Total operating expenses	$ 71,500	$ 69,120	$ 64,123	$ 60,083	$ 47,347	$ 41,515	$ 30,311	$ 21,890	$ 264,826	$ 141,063	$ 55,857
Net loss	$ (75,014)	$ (70,633)	$ (65,770)	$ (62,134)	$ (48,253)	$ (41,777)	$ (29,908)	$ (23,317)	$ (273,551)	$ (143,255)	$ (83,440)
Net loss per share attributable to common shareholders - basic and diluted (in USD per share)	$ (1.07)	$ (1.04)	$ (0.99)	$ (0.98)	$ (0.81)	$ (0.70)	$ (0.50)	$ (0.39)	$ (4.09)	$ (2.41)	$ (1.70)

- Definition

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

+ References + Details

Label	Element	Value
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 0
Additional Paid-in Capital [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	122,000
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ (122,000)