Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Mar. 31, 2018	Jun. 04, 2018	Sep. 30, 2017
Document and Entity Information
Entity Registrant Name	Myovant Sciences Ltd.
Entity Central Index Key	0001679082
Document Type	10-K
Document Period End Date	Mar. 31, 2018
Amendment Flag	false
Current Fiscal Year End Date	--03-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		64,875,000
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Entity Public Float			$ 339,112,069
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Current assets:
Cash	$ 108,624	$ 180,838
Prepaid expenses and other current assets	5,139	3,221
Income tax receivable	1,000	105
Total current assets	114,763	184,164
Deferred tax assets	0	208
Furniture and equipment, net	1,273	906
Other assets	3,065	0
Total assets	119,101	185,278
Current liabilities:
Accounts payable	4,578	3,329
Interest payable	282	0
Accrued expenses	30,265	11,978
Due to Roivant Sciences Ltd., Roivant Sciences, Inc. and Roivant Sciences GmbH	1,960	3,030
Total current liabilities	37,085	18,337
Takeda warrant liability	0	52
Deferred rent	408	113
Deferred interest payable	255	0
Long-term debt	43,624	0
Total liabilities	81,372	18,502
Commitments and contingencies (Note 11)
Shareholders’ equity:
Common shares, par value $0.000017727 per share, 564,111,242 shares authorized, 60,997,856 and 60,275,757 issued and outstanding at March 31, 2018 and 2017, respectively	1	1
Common shares subscribed	0	(1)
Additional paid-in capital	266,178	251,733
Accumulated other comprehensive income	24	140
Accumulated deficit	(228,474)	(85,097)
Total shareholders’ equity	37,729	166,776
Total liabilities and shareholders’ equity	$ 119,101	$ 185,278

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2018	Mar. 31, 2017
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)	60,997,856	60,275,757
Common shares outstanding (in shares)	60,997,856	60,275,757

Consolidated Statements of Operations - USD ($) $ in Thousands	2 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
Operating expenses:
Research and development (includes $3,674, $3,893 and $0 of share-based compensation expense for the years ended March 31, 2018 and 2017 and the period from February 2, 2016 (Date of Inception) to March 31, 2016, respectively)	$ 0	$ 116,832	$ 43,500
General and administrative (includes $7,909, $4,824 and $987 of share-based compensation expense for the years ended March 31, 2018 and 2017 and the period from February 2, 2016 (Date of Inception) to March 31, 2016, respectively)	1,657	24,231	12,357
Total operating expenses	1,657	141,063	55,857
Changes in the fair value of the Takeda warrant liability	0	0	27,518
Interest expense	0	2,046	0
Other (income) expense	0	(67)	139
Loss before income taxes	(1,657)	(143,042)	(83,514)
Income tax expense (benefit)	0	213	(74)
Net loss	$ (1,657)	$ (143,255)	$ (83,440)
Net loss per common share — basic and diluted (in USD per share)	$ (0.04)	$ (2.41)	$ (1.70)
Weighted average common shares outstanding — basic and diluted (in shares)	37,231,342	59,520,747	49,184,668

Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands	2 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
Share-based compensation	$ 987	$ 11,583	$ 8,717
Research and development
Share-based compensation	0	3,674	3,893
General and administrative
Share-based compensation	$ 987	$ 7,909	$ 4,824

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	2 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (1,657)	$ (143,255)	$ (83,440)
Other comprehensive (loss) income:
Foreign currency translation adjustment	0	(116)	140
Total other comprehensive (loss) income	0	(116)	140
Comprehensive loss	$ (1,657)	$ (143,371)	$ (83,300)

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
Beginning balance (in shares) at Feb. 02, 2016		37,231,342
Beginning balance at Feb. 02, 2016	$ 0	$ 1	$ (1)	$ 0	$ 0	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Capital contribution	1,434			1,434
Foreign currency translation adjustment	0
Net loss	(1,657)					(1,657)
Ending balance (in shares) at Mar. 31, 2016		37,231,342
Ending 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
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	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]
Adjustment to adopt ASU 2016-09	0			122		(122)
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
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 to Hercules with long-term debt	789			789
Settlement of Roivant Sciences Ltd. 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)

Consolidated Statement of Cash Flows - USD ($) $ in Thousands	2 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net loss	$ (1,657)	$ (143,255)	$ (83,440)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation	1,434	11,583	8,717
Depreciation	0	243	61
Amortization of debt discount and issuance costs	0	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
Foreign currency translation adjustment	0	(116)	140
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	0	(1,918)	(3,221)
Deferred tax assets	0	208	(208)
Income tax receivable	0	(895)	(105)
Other assets	0	(3,065)	0
Accounts payable	0	1,249	3,329
Interest payable	0	282	0
Accrued expenses	223	18,287	11,755
Due to Roivant Sciences Ltd., Roivant Sciences, Inc. and Roivant Sciences GmbH	0	(1,070)	4,009
Deferred rent	0	295	113
Deferred interest payable	0	255	0
Net cash used in operating activities	0	(117,255)	(18,215)
Cash flows from investing activities:
Purchase of furniture and equipment		(604)	(967)
Net cash used in investing activities		(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 debt financings, net of financing costs	0	43,751	0
Cash proceeds from issuance of common shares to NovaQuest, net of issuance costs	0	1,857	0
Cash capital contribution from Roivant Sciences Ltd.	0	0	1,035
Settlement of Roivant Sciences Ltd. common shares subscribed	0	1	0
Stock option exercises	0	36	0
Due to Roivant Sciences Ltd. and Roivant Sciences, Inc. for amounts paid on behalf of the Company	0	0	(979)
Net cash provided by financing activities	0	45,645	200,020
Net change in cash	0	(72,214)	180,838
Cash—beginning of period	0	180,838	0
Cash—end of period	0	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	$ 0	$ 845	$ 0

Description of Business	12 Months Ended
Description of Business	Mar. 31, 2018
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 biopharmaceutical company focused on developing and commercializing innovative therapies for the treatment of women’s health and endocrine diseases. The Company is developing its lead product candidate, relugolix, for the treatment of heavy menstrual bleeding associated with uterine fibroids, endometriosis-associated pain and advanced prostate cancer, and its second product candidate, MVT-602, for the treatment of female infertility as part of the hormonal preparation used in assisted reproduction, both of which were licensed from Takeda Pharmaceuticals International AG, or Takeda, on April 29, 2016. The Company is an exempted limited company 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. The Company has four wholly owned subsidiaries. Roivant Endocrinology Inc. was incorporated in Delaware in April 2016 and subsequently changed its name to Myovant Sciences, Inc., or MSI. Myovant Holdings Limited, or MHL, a private limited company incorporated under the laws of England and Wales, and Myovant Sciences GmbH, or MSG, a company with limited liability formed under the laws of Switzerland, were each organized in August 2016. Myovant Sciences Ireland Limited, or MSIL, a company with limited liability formed under the laws of Ireland, was organized in April 2017. MSG holds the Company’s intellectual property rights and is the Company’s principal operating subsidiary. Since its inception, the Company has devoted substantially all of its efforts to organizing and staffing the Company, raising capital, identifying and in-licensing its product candidates, including acquiring worldwide rights (excluding Japan and certain other Asian countries) to relugolix and worldwide rights to MVT-602, preparing for and advancing the clinical development of its product candidates, and preparing for the potential commercialization of relugolix. 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 Company has incurred and expects to continue to incur significant and increasing operating losses and negative cash flows for at least the next several years. The Company does not expect to generate revenue unless and until it successfully completes development and obtains regulatory approval for one of its product candidates. The Company believes its existing cash, together with the remaining financing commitments of $92.0 million available to it from NovaQuest will be sufficient to fund its operations for at least the next 12 months. This estimate is based on the Company’s current assumptions, including assumptions relating to its ability to manage its spend, that may prove to be wrong, and it could use its available capital resources sooner than it currently expects. The Company may need to obtain further funding through other public or private offerings of its capital shares, debt financing, collaboration and licensing arrangements or other sources. Adequate additional funding may not be available to the Company on acceptable terms, or at all.

Summary of Significant Accounting Policies

12 Months Ended

Mar. 31, 2018

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

(A) Basis of Presentation:

The Company’s fiscal year ends on March 31, and its fiscal quarters end on June 30, September 30 and December 31.

The accompanying consolidated financial statements have been prepared in accordance with United States 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 as found 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 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 parent company, Roivant Sciences Ltd., or RSL, as well as share-based compensation expenses, research and development, or R&D, expenses, 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 is subject to risks common to companies in the pharmaceutical industry including, but not limited to, uncertainties related to commercialization of products, regulatory approvals, dependence on key products, third-party service providers such as contract research organizations, or CROs, and contract manufacturing organizations, or CMOs, and protection of intellectual property rights.

(D) Concentrations of Credit Risk:

Financial instruments that potentially subject the Company to concentration of credit risk include cash. At March 31, 2018, substantially all of the Company’s cash balances are deposited in three banking institutions and are all in excess of insured levels. The Company is exposed to credit risk in the event of default by the financial institutions holding its cash.

(E) Property and Equipment:

Property and equipment, 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.

(F) 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 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.

(G) 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 in 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.

(H) 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 reasonably possible loss exists, the Company discloses the facts and circumstances of the contingency, including an estimable range, if possible.

(I) Deferred Offering Costs:

Deferred offering costs consist of qualified legal, accounting, and other direct costs related to the Company’s efforts to raise capital through a public or private sale of the Company’s capital stock. These costs are deferred until the completion of the applicable offering, at which time such costs are reclassified to additional paid-in-capital as a reduction of the proceeds.

(J) 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. Payments for a product license prior to regulatory approval of the product and payments for milestones achieved prior to regulatory approval of the product are expensed in the period incurred as R&D. 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 R&D personnel, the intellectual property and R&D materials acquired from Takeda, certain costs billed by RSI and RSG under their 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.

(K) 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 as other expense (income). The Takeda warrant liability expired on April 30, 2017.

(L) 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.

(M) Share-Based Compensation:

The Company recognizes share-based compensation expense related to stock options granted to employees and members of its board of directors based on the estimated fair value of the awards on the date of grant. The Company estimates the grant date fair value, and the resulting share-based compensation expense, using the Black-Scholes option-pricing model. The grant date fair value of the share-based awards is generally recognized on a straight-line basis over the requisite service period, which is generally the vesting period of the respective awards.

The Company recognizes share-based compensation expense related to stock options granted to non-employees issued in exchange for services based on the estimated fair value of the awards on the date of grant. The Company estimates the grant date fair value, and the resulting share-based compensation expense, using the Black-Scholes option-pricing model; however, the fair value of the stock options granted to non-employees is remeasured each reporting period until the service is complete, and the resulting increase or decrease in fair value, if any, is recognized as expense or income, respectively, during the period the related services are rendered.

The Black-Scholes option-pricing model requires the use of highly subjective assumptions, which are used to determine the fair value of share-based awards. 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 noted under the provisions of Staff Accounting Bulletin, or SAB No. 107, with the continued use of this method extended under the provisions of SAB 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.

RSL common share awards and RSL options granted by RSL to RSL, RSI and RSG 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. As RSL is a non-public entity, the RSL common share awards and RSL options are classified as Level 3 by RSL due to their unobservable nature. 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 on the relative percentage of time utilized by RSL, RSI and RSG employees on the Company’s matters.

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 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.

Prior to the Company’s IPO, it was required to periodically estimate the fair value of its common shares when issuing share awards and options and in computing its estimated share-based compensation expense. In order to determine the fair value of the equity awards, the Company’s board of directors considered, among other things, timely valuations of the common shares prepared by an unrelated third-party valuation firm in accordance with guidance provided by the American Institute of Certified Public Accountants Practice Guide, Valuation of Privately-Held Company Equity Securities Issued as Compensation. In connection with the Company’s IPO and after discussions with the underwriters, it reassessed the fair value of these awards. Subsequent to the Company’s IPO, the estimated fair value of share-based payment awards has been determine as indicated in the preceding paragraphs.

Prior to April 1, 2017, the Company estimated pre-vesting award forfeitures based on the Company’s expectations of future employee turnover and adjusted its estimate of forfeitures over the requisite service period based on the extent to which actual forfeitures differed, or were expected to differ, from such estimates. Any changes in estimated forfeitures were recognized through a cumulative catch-up adjustment in the period of change which also impacted the amount of compensation expense to be recognized in future periods. On April 1, 2017, The Company adopted ASU No. 2016-09, “Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting,” or ASU No. 2016-09, in which it elected to change its accounting policy from estimating forfeitures to recognizing such forfeitures when they occur (see Note 2 (Q), “Recently Issued Accounting Pronouncements,” for further details.)

(N) 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 share 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.

The following potentially dilutive securities have been excluded from the diluted net loss per common share calculations for the years ended March 31, 2018 and 2017, and for the period from February 2, 2016 (Date of Inception) to March 31, 2016:



	Years Ended March 31,		Period from February 2, 2016 (Date of Inception) to March 31,
	2018	2017	2016
Options	3,549,405	1,525,857	—
Restricted share awards	1,198,735	1,128,222	—
Restricted stock units	15,000	—	—
Warrants	73,710	—	—
Total	4,836,850	2,654,079	—

(O) 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, accounts payable and long-term debt. Cash 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 long-term 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.

(P) 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 income (expense) in the Company’s consolidated statements of operations.

(Q) Recently Issued Accounting Pronouncements:

In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842),” or ASU No. 2016-02, which is a comprehensive new lease standard that amends various aspects of existing accounting guidance for leases. The core principle of ASU No. 2016-02 will require lessees to present the assets and liabilities that arise from leases on their balance sheets. ASU No. 2016-02 is effective for annual periods beginning after December 15, 2018, and interim periods within fiscal years beginning after December 15, 2018. Early adoption is permitted. The Company is currently evaluating the new standard and its impact on the Company’s consolidated financial statements and related disclosures.

In March 2016, the FASB issued ASU No. 2016-09, “Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting,” or ASU No. 2016-09. ASU No. 2016-09 makes several modifications to Topic 718 related to the accounting for forfeitures, employer tax withholding on share-based compensation, and the financial statement presentation of excess tax benefits or deficiencies. ASU No. 2016-09 also clarifies the statement of cash flows presentation for certain components of share-based awards. The Company adopted this guidance as of April 1, 2017 using a modified retrospective transition method. As a result of the adoption of this standard, the Company elected to change its accounting policy from estimating forfeitures to recognizing forfeitures when they occur and, as a result, recorded an adjustment of $0.1 million to increase accumulated deficit with a corresponding offset to additional paid-in-capital as of April 1, 2017. The other requirements of ASU No. 2016-09 did not have a material impact on the Company’s consolidated financial statements and related disclosures.

In October 2016, the FASB issued ASU No. 2016-16, “Intra-Entity Transfers of Assets Other Than Inventory,” or ASU No. 2016-16. ASU No. 2016-16 requires the income tax consequences of intra-entity transfers of assets other than inventory to be recognized as current period income tax expense or benefit and removes the requirement to defer and amortize the consolidated tax consequences of intra-entity transfers. The new standard will be effective for the Company on April 1, 2018 and will be adopted using a modified retrospective approach which requires a cumulative effect adjustment to retained earnings as of the beginning of the period of adoption. The Company is currently evaluating the new standard and its impact on the Company’s consolidated financial statements and related disclosures.

In February 2018, the FASB issued ASU No. 2018-02, “Income Statement-Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income,” or ASU No. 2018-02. ASU No. 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 No. 2018-02 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2018. Early adoption is permitted. The Company is currently evaluating the new standard and its impact on the Company’s consolidated financial statements and related disclosures.

In March 2018, the FASB issued ASU No. 2018-05, “Income Taxes (Topic 740): Amendments to SEC Paragraphs Pursuant to SEC Staff Accounting Bulletin No. 118,” or ASU No. 2018-05. ASU No. 2018-05 amends certain SEC material in Topic 740 for the income tax accounting implications of the recently issued Tax Cuts and Jobs Act. ASU No. 2018-05 is effective immediately. The Company evaluated the impact of the Act as well as the guidance of Staff Accounting Bulletin No. 118 and incorporated the changes into the determination of a reasonable estimate of its deferred taxes and appropriate disclosures in the notes to the Company’s consolidated financial statements. The Company considers its accounting for the impact of the new law to be provisional and will continue to evaluate the impact this recent tax reform legislation may have on its results of operations, financial position, cash flows and related disclosures.

License Agreement

12 Months Ended

Mar. 31, 2018

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 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 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. The Company will need to independently develop all clinical processes and procedures for its clinical trials through the use of internal and external resources once appropriate and acceptable resources have been identified and obtained. 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.

Long-term Debt

12 Months Ended

Mar. 31, 2018

Debt Disclosure [Abstract]

Long-term Debt

(A) NovaQuest Long-term Debt

In October 2017, the Company, its subsidiaries, MSI, MHL, MSG and MSIL, 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 has 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 is 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 will be 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 has committed that it will issue at least $30.0 million aggregate principal amount of notes through December 31, 2018, subject to certain terms and conditions, of which $6.0 million aggregate principal amount was issued in October 2017. With this issuance of $6.0 million aggregate principal amount of notes in October 2017, NovaQuest also purchased 138,361 common shares for $2.0 million in accordance with the terms of the NovaQuest Securities Purchase Agreement.

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 option of the Company to November 1, 2021, or the Amortization Date, provided certain terms and conditions are met as set forth in the NovaQuest Securities Purchase Agreement. 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 has 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 as set forth in the NovaQuest Equity Purchase Agreement. The Company has committed that it will 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. The purchase price for the common shares issued pursuant to the NovaQuest Equity Purchase Agreement will be 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 which are recorded as an offset to long-term debt on the Company’s consolidated balance sheets. These deferred financing costs are being amortized over the term of the debt using the effective interest method, and are included in interest expense in the Company’s consolidated statements of operations. During the year ended March 31, 2018, interest expense included $0.2 million of amortized deferred financing costs related to the NovaQuest notes.

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



	March 31, 2018

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

(B) Hercules Long-term Debt

In October 2017, the Company, its subsidiaries, MSI, MHL, MSG and MSIL as guarantors, and Hercules Capital, Inc., or Hercules, entered into a Loan Agreement, or the Hercules Loan Agreement, which provides 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 8.75% at March 31, 2018. The Term Loans mature on May 1, 2021, subject to extension to November 1, 2021 if certain milestones are met. The Company is obligated to make monthly payments of accrued interest until June 1, 2019, or the Interest-only Period, followed by monthly installments of principal and interest through the maturity date. The Interest-only Period may be extended until June 1, 2020 if certain milestones are met as defined 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 at maturity. The Company’s obligations under the Hercules Loan Agreement are secured by a second 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 certain 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 is 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 exercise 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 years	7.00 years

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 relating to the Hercules Loan Agreement which are recorded as an offset to long-term debt on the Company’s consolidated balance sheets. 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. The debt discount and deferred financing costs are being amortized over the term of the debt using the effective interest method, and are included in interest expense in the Company’s consolidated statements of operations. During the year ended March 31, 2018, interest expense included $0.5 million of amortized debt discount and issuance costs related to the Term Loans.

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



	March 31, 2018

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

Annual maturities of long-term debt outstanding as of March 31, 2018 are as follows (in thousands):



Years Ended March 31,

2019	$	—
2020	15,779
2021	21,464
2022	5,526
2023	1,846
Thereafter	1,385
Total	$	46,000

Related Party Transactions	12 Months Ended
Related Party Transactions	Mar. 31, 2018
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions (A) Services Agreements: In July 2016, the Company entered into a formal 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 the employee compensation expense plus a pre-determined mark-up. RSI also provided such services to the Company prior to the formalization of the service agreement, and such costs have been recognized by the Company in the period in which the services were rendered. Employee compensation expense, inclusive of base salary and fringe benefits, is determined based upon the relative percentage of time utilized on Company matters by the respective employee, which the Company believes is reasonable. All other third-party pass thru costs are billed to the Company at cost. The accompanying 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 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, 2018 and 2017 and the period from February 2, 2016 (Date of Inception) to March 31, 2016, the Company incurred expenses (inclusive of third party pass thru costs billed to the Company) of $7.7 million, $9.2 million, and $0.4 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. (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 and RSG employees, the Company recorded share-based compensation expense of $1.0 million, $4.9 million and $1.0 million, respectively, for the years ended March 31, 2018 and 2017 and for the period from February 2, 2016 (Date of Inception) to March 31, 2016. Refer to Note 9(E)(2) for further details. (C) Option Agreement: 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. (D) Information Sharing and Cooperation Agreement: 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 United States Securities and Exchange Commission, or 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. (E) 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 will supply the Company, and the Company will obtain from Takeda Limited, all of its requirements for relugolix drug substance and drug product to be used under its development plans for all indications. If the Company requests, Takeda Limited will assist it with a technical transfer of the manufacturing process for relugolix to it or its designee and the Company will pay the expenses related to such transfer.

Shareholders' Equity (Deficit)	12 Months Ended
Shareholders' Equity (Deficit)	Mar. 31, 2018
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, 2018, 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 payable by the Company. (C) 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, 2018

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,						Period from February 2, 2016 (Date of Inception) to March 31,
	2018			2017			2016
Loss before income taxes:
United States	$	(7,229	)	$	(2,924	)	$	—
Switzerland	(129,261		)	(29,745		)	—
Bermuda	(6,513		)	(50,845		)	(1,657		)
Other⁽¹⁾	(39		)	—			—
Total loss before income taxes	$	(143,042	)	$	(83,514	)	$	(1,657	)

Current taxes:
United States	$	13		$	125		$	—
Switzerland	—			—			—
Bermuda	—			—			—
Other⁽¹⁾	(8		)	9			—
Total current tax expense	5			134			—
Deferred taxes:
United States	208			(208		)	—
Switzerland	—			—			—
Bermuda	—			—			—
Other⁽¹⁾	—			—			—
Total deferred tax benefit	208			(208		)	—
Total income tax expense (benefit)	$	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										Period from February 2, 2016 (Date of Inception) to March 31,
	2018					2017					2016
Income tax benefit at Bermuda statutory rate	$	—		—	%	$	—		—	%	$	—	—	%
Foreign rate differential⁽²⁾	(14,802		)	10.35		(7,592		)	9.09		—		—
Valuation allowance	13,966			(9.77	)	7,378			(8.83	)	—		—
Tax reform	1,049			(0.73	)	—			—		—		—
Other	—			—		140			(0.17	)	—		—
Total income tax expense (benefit)	$	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, 2018 and 2017 and for the period from February 2, 2016 (Date of Inception) to March 31, 2016 was (0.15)%, 0.09% and 0.00%, 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.

On December 22, 2017, the Tax Cuts and Jobs Act, or the Act, was enacted, which introduced a comprehensive set of tax reform in the United States. The Act revises the U.S. corporate income tax by, among other things, lowering the corporate income tax rate from 35% to 21%, adopting a quasi-territorial income tax system and imposing a one-time transition tax on foreign unremitted earnings, and setting limitations on deductibility of certain costs (e.g., interest expense).

The effects of changes in tax laws are required to be recognized in the period in which the legislation is enacted in accordance with ASC 740, Accounting for Income Taxes. However, due to the complexity and significance of the Act’s provisions, the SEC staff issued Staff Accounting Bulletin No. 118, which allows companies to record the tax effects of the Act on a provisional basis based on a reasonable estimate, and then, if necessary, subsequently adjust such amounts during a limited measurement period as more information becomes available. The measurement period ends when a company has obtained, prepared, and analyzed the information necessary to finalize its accounting, but cannot extend beyond one year from enactment.

The Act did not have a material impact on the Company’s consolidated financial statements since its global net deferred tax assets are fully offset by a valuation allowance and the Company does not have any off-shore earnings from which to record the mandatory transition tax. However, given the significant complexity of the Act, anticipated guidance from the U.S. Treasury about implementing the Act, and the potential for additional guidance from the SEC or the FASB related to the Act, these estimates may be adjusted during the measurement period. The provisional amounts were based on the Company’s present interpretations of the Act and currently available information, including assumptions and expectations about future events, such as its projected financial performance, and are subject to further refinement as additional information becomes available (such as potential new or interpretative guidance issued by the FASB or the Internal Revenue Service and other tax agencies) and further analyses are completed. The Company continues to analyze the changes in certain income tax deductions and gather additional data to compute the full impact on the Company’s current and deferred tax assets and liabilities (deferred tax assets and liabilities will be subject to a valuation allowance if adjusted).

As of March 31, 2018, the Company had an aggregate income tax receivable of $1.0 million from various federal, state, and local jurisdictions.

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 at March 31, 2018 and 2017 are as follows (in thousands):



	March 31, 2018			March 31, 2017
Deferred tax assets:
Research tax credits	$	2,948		$	163
Net operating loss⁽³⁾	16,045			6,019
Share-based compensation	2,380			1,382
Other	169			300
Subtotal	21,542			7,864
Valuation allowance	(21,367		)	(7,401		)

Deferred tax liabilities:
Depreciation	(175		)	(255		)

Total deferred tax assets	$	—		$	208

(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.

As of March 31, 2018, the Company’s net operating losses in Switzerland, Ireland, and the United Kingdom were $155.5 million, $23 thousand, and $6.7 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, 2018, the Company has research and development credit carryforwards in the United States in the amount of $2.9 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 $21.4 million as of March 31, 2018 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, 2018.

Share-Based Compensation

12 Months Ended

Mar. 31, 2018

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. At March 31, 2018, a total of 1.7 million common shares were available for future issuance under the 2016 Plan. On April 1, 2017, 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.

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 option activity and data under the Company’s 2016 Plan for the year ended March 31, 2018 is as follows:



	Number of Options		Weighted Average Exercise Price		Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Life	Aggregate Intrinsic Value (in thousands)
Options outstanding at March 31, 2017	1,525,857		$	5.06	$	11.90
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
Options vested and expected to vest at March 31, 2018	3,549,405		$	9.84	$	9.60	9.02	$	40,557
Options exercisable at March 31, 2018	502,361		$	4.88	$	11.95	8.49	$	8,235

At March 31, 2018 and 2017, there were 502,361 and 28,406 vested options, respectively. No options vested during the period from February 2, 2016 (Date of Inception) to March 31, 2016. Additional information regarding options is set forth below (in thousands, except per share data).



	Years Ended March 31,				Period from February 2, 2016 (Date of Inception) to March 31,
	2018		2017		2016
Intrinsic value of options exercised	$	181	$	—	$	—
Grant date fair value of options vested	$	5,831	$	350	$	—
Weighted-average grant date fair value per share of options granted	$	8.35	$	11.90	$	—

A summary of restricted share award and restricted stock unit activity under the Company’s 2016 Plan for the year ended March 31, 2018 is as follows:



	Number of shares		Weighted Average Grant Date Fair Value
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

The total fair value of restricted share awards vested during the year ended March 31, 2018 was $2.5 million. No restricted share awards vested during the year ended March 31, 2017 or period from February 2, 2016 (Date of Inception) to March 31, 2016. No restricted stock units have vested as of March 31, 2018.

(D) Share-Based Compensation Expense

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



	Years Ended March 31,				Period from February 2, 2016 (Date of Inception) to March 31,
	2018		2017		2016
Share-based compensation expense recognized as:
R&D expenses	$	3,674	$	3,893	$	—
G&A expenses	7,909		4,824		987
Total	$	11,583	$	8,717	$	987

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).

Total unrecognized share-based compensation expense was approximately $33.7 million at March 31, 2018 and is expected to be recognized over a weighted-average period of approximately 3.16 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,				Period from February 2, 2016 (Date of Inception) to March 31,
	2018		2017		2016
Expected common share price volatility	74.4	%	75.5	%	—	%
Expected risk free interest rate	2.04	%	1.57	%	—	%
Expected term, in years	6.22		6.35		—
Expected dividend yield	—	%	—	%	—	%

In connection with the Company’s IPO and after discussions with the underwriters, the Company reassessed the fair value of: (1) 1.1 million restricted common share awards issued to its Principal Executive Officer in June 2016 with an initial fair value of $1.52 per common share; (2) 0.6 million common shares underlying stock options granted in August 2016 (including options to purchase 0.1 million common shares granted to certain consultants as described below in Note 9(E)(1) with an exercise price of $2.38 per common share; and (3) 0.6 million common shares underlying stock options granted in September 2016 to the Company’s employees, officers and directors with a weighted-average exercise price of $4.00 per common share. As a result, the Company determined that the reassessed fair value of the restricted common share awards was $5.10 per common share and the reassessed fair value of the common shares underlying the stock options granted in August and September 2016 was $15.00 per common share, which was the IPO price of the Company’s common shares. The use of this higher fair value per common share increased the weighted-average fair value of the stock options granted in August and September 2016 to $13.44 per common share and $12.78 per common share, respectively. Prior to the IPO, the fair value of the common shares underlying the Company’s stock options was estimated on each grant date by the board of directors. In order to determine the fair value of the Company’s common shares underlying granted stock options, the board of directors considered, among other things, timely valuations of the common shares prepared by an unrelated third-party valuation firm in accordance with the guidance provided by the American Institute of Certified Public Accountants Practice Guide, Valuation of Privately-Held-Company Equity Securities Issued as Compensation. The use of this higher share price increased both recognized and unrecognized share-based compensation expense.

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

(1) Stock Options Granted to Non-Employees:

During the year ended March 31, 2017, the Company granted options to purchase 0.1 million common shares to certain consultants, who are also employees of RSI, with a weighted average exercise price of $2.41. As discussed above in Note 9(D), the use of the higher fair value per common share of $15.00, which was reassessed in conjunction with the IPO and after discussions with the underwriters, increased both recognized and unrecognized share-based compensation expense. No options were granted to consultants during the year ended March 31, 2018 or period from February 2, 2016 (Date of Inception) to March 31, 2016. For the years ended March 31, 2018 and 2017, share-based compensation expense related to stock options granted to consultants was $0.3 million and $0.4 million, respectively. There was no share-based compensation expense for the period from February 2, 2016 (Date of Inception) to March 31, 2016. At March 31, 2018, total unrecognized compensation expense related to stock options granted to consultants was approximately $0.1 million, which is expected to be recognized over approximately 2.38 years.

(2) 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 and RSG employees, the Company recorded share-based compensation expense of $1.0 million, $4.9 million and $1.0 million, respectively, for the years ended March 31, 2018 and 2017 and for the period from February 2, 2016 (Date of Inception) to March 31, 2016.

The RSL common share awards and RSL options granted by RSL to RSL, RSI and RSG 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. As RSL is a non-public entity, the RSL common share awards and RSL options are classified as Level 3 by RSL due to their unobservable nature. 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.

(3) RSL RSUs:

The Company’s Principal Executive Officer was granted 66,845 RSUs of RSL during the year ended March 31, 2017. These RSUs have a requisite service period of eight years and have no dividend rights. These RSUs will vest upon the achievement of both a performance and market condition, if both are achieved within the requisite service period. As of March 31, 2018, the performance conditions had not been met and were deemed not probable of being met. For the years ended March 31, 2018 and 2017, the Company recorded no share-based compensation expense related to these RSUs. At March 31, 2018, 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, 2018

Fair Value Disclosures [Abstract]

Fair Value Measurements

The following table sets forth the Company’s liabilities that are measured at fair value on a recurring basis as of March 31, 2018 and 2017, by level, within the fair value hierarchy (in thousands):



	As of March 31, 2018								As of March 31, 2017

	Level 1		Level 2		Level 3		Balance as of March 31, 2018		Level 1		Level 2		Level 3		Balance as of March 31, 2017
Liabilities:
Takeda warrant liability	$	—	$	—	$	—	$	—	$	—	$	—	$	52	$	52
Total liabilities at fair value	$	—	$	—	$	—	$	—	$	—	$	—	$	52	$	52

There were no transfers of assets between Level 1 and Level 2 of the fair value hierarchy that occurred during the year ended March 31, 2018.

Level 3 Disclosures

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 accompanying 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, 2018

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

The Company has entered into commitments under its license agreement with Takeda (See Note 3), services agreements with RSI and RSG (See Note 6(A)), and financing agreements with NovaQuest and Hercules (See Note 5). In addition, the Company has entered into services agreements with third parties for pharmaceutical R&D and manufacturing activities and has a lease agreement for office space located in Brisbane, California. Expenditures to contract research organizations, or CROs, and contract manufacturing organizations, or CMOs, 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 commitments as its business further develops.

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 leases 40,232 square feet of office space located in Brisbane, California, pursuant to an operating lease agreement that expires in May of 2026. The Company has the option to extend the lease term for an additional seven years.

Future operating lease obligations (excluding the optional lease renewal term) as of March 31, 2018 are as follows (in thousands):



Years Ended March 31,	Operating Leases

2019	$	1,347
2020	2,009
2021	2,063
2022	2,127
2023	2,200
Thereafter	7,650
Total minimum operating lease payments	$	17,396

Rent expense for the years ended March 31, 2018 and 2017 was $0.9 million and $0.3 million, respectively. The Company had no rent expense for the period from February 2, 2016 (Date of Inception) to March 31, 2016.

Selected Quarterly Data (Unaudited)

12 Months Ended

Mar. 31, 2018

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, 2018 and 2017. The unaudited quarterly financial data is prepared on the same basis as the audited consolidated financial statements. 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 2018 and 2017 quarters have been computed separately.



	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,
	2017			2017			2017			2018			2016 ⁽¹⁾			2016			2016			2017
Total operating expenses	$	21,890		$	30,311		$	41,515		$	47,347		$	17,135		$	6,720		$	9,056		$	22,946
Net loss	$	(23,317	)	$	(29,908	)	$	(41,777	)	$	(48,253	)	$	(18,970	)	$	(34,712	)	$	(8,083	)	$	(21,675	)
Net loss per share attributable to common shareholders - basic and diluted	$	(0.39	)	$	(0.50	)	$	(0.70	)	$	(0.81	)	$	(0.47	)	$	(0.82	)	$	(0.15	)	$	(0.37	)

(1)

On April 29, 2016, the Company entered into a license agreement with Takeda. As a result of this transaction, the Company recorded $13.1 million as R&D expense at the closing date of the acquisition of the rights, 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 Takeda warrant liability. Refer to Note 3 for additional information.

Subsequent Events	12 Months Ended
Subsequent Events	Mar. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events (A) Private Placement with RSL On April 2, 2018, the Company entered into a share purchase agreement, or the Purchase Agreement, with RSL pursuant to which the Company agreed to issue and sell to RSL 1,110,015 of its common shares at a purchase price of $20.27 per common share in a private placement, or the Private Placement. In April 2018, the Company received gross proceeds of $22.5 million from RSL at the closing of the Private Placement. (B) At-the-Market Equity Offering Program On April 2, 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. In the first quarter of fiscal year 2018, the Company issued and sold 2,767,129 of its common shares under the Sales Agreement. The common shares were sold at a weighted-average-price of $21.47 per common share for aggregate net proceeds to the Company of approximately $57.6 million, after deducting commissions. (C) Commercial Manufacturing and Supply Agreement with Takeda 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.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Mar. 31, 2018

Accounting Policies [Abstract]

Basis of Accounting

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

Use of Estimates

Concentrations of Credit Risk

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

Deferred Offering Costs

Research and Development Expenses

Takeda Warrant Liability

Income Taxes

Share-based Compensation

The Black-Scholes option-pricing model requires the use of highly subjective assumptions, which are used to determine the fair value of share-based awards. These assumptions include:

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.

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

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Mar. 31, 2018

Accounting Policies [Abstract]

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share



	Years Ended March 31,		Period from February 2, 2016 (Date of Inception) to March 31,
	2018	2017	2016
Options	3,549,405	1,525,857	—
Restricted share awards	1,198,735	1,128,222	—
Restricted stock units	15,000	—	—
Warrants	73,710	—	—
Total	4,836,850	2,654,079	—

Long-term Debt (Tables)

12 Months Ended

Mar. 31, 2018

Debt Disclosure [Abstract]

Schedule of Outstanding Debt Obligations

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



	March 31, 2018

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

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



	March 31, 2018

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

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 years	7.00 years

Schedule of Maturities of Long-term Debt

Annual maturities of long-term debt outstanding as of March 31, 2018 are as follows (in thousands):



Years Ended March 31,

2019	$	—
2020	15,779
2021	21,464
2022	5,526
2023	1,846
Thereafter	1,385
Total	$	46,000

- 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://www.xbrl.org/2003/role/presentationRef
-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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21475-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-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 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21538-112644

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21506-112644

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21521-112644

+ Details

Income Taxes (Tables)

12 Months Ended

Mar. 31, 2018

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,						Period from February 2, 2016 (Date of Inception) to March 31,
	2018			2017			2016
Loss before income taxes:
United States	$	(7,229	)	$	(2,924	)	$	—
Switzerland	(129,261		)	(29,745		)	—
Bermuda	(6,513		)	(50,845		)	(1,657		)
Other⁽¹⁾	(39		)	—			—
Total loss before income taxes	$	(143,042	)	$	(83,514	)	$	(1,657	)

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


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

Schedule of Effective Income Tax Reconciliation



	Years Ended March, 31										Period from February 2, 2016 (Date of Inception) to March 31,
	2018					2017					2016
Income tax benefit at Bermuda statutory rate	$	—		—	%	$	—		—	%	$	—	—	%
Foreign rate differential⁽²⁾	(14,802		)	10.35		(7,592		)	9.09		—		—
Valuation allowance	13,966			(9.77	)	7,378			(8.83	)	—		—
Tax reform	1,049			(0.73	)	—			—		—		—
Other	—			—		140			(0.17	)	—		—
Total income tax expense (benefit)	$	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 at March 31, 2018 and 2017 are as follows (in thousands):



	March 31, 2018			March 31, 2017
Deferred tax assets:
Research tax credits	$	2,948		$	163
Net operating loss⁽³⁾	16,045			6,019
Share-based compensation	2,380			1,382
Other	169			300
Subtotal	21,542			7,864
Valuation allowance	(21,367		)	(7,401		)

Deferred tax liabilities:
Depreciation	(175		)	(255		)

Total deferred tax assets	$	—		$	208

(3)

Share-Based Compensation (Tables)

12 Months Ended

Mar. 31, 2018

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

Summary of Stock Option Activity

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



	Years Ended March 31,				Period from February 2, 2016 (Date of Inception) to March 31,
	2018		2017		2016
Intrinsic value of options exercised	$	181	$	—	$	—
Grant date fair value of options vested	$	5,831	$	350	$	—
Weighted-average grant date fair value per share of options granted	$	8.35	$	11.90	$	—

A summary of option activity and data under the Company’s 2016 Plan for the year ended March 31, 2018 is as follows:



	Number of Options		Weighted Average Exercise Price		Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Life	Aggregate Intrinsic Value (in thousands)
Options outstanding at March 31, 2017	1,525,857		$	5.06	$	11.90
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
Options vested and expected to vest at March 31, 2018	3,549,405		$	9.84	$	9.60	9.02	$	40,557
Options exercisable at March 31, 2018	502,361		$	4.88	$	11.95	8.49	$	8,235

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 year ended March 31, 2018 is as follows:



	Number of shares		Weighted Average Grant Date Fair Value
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

Schedule of Share-based Compensation

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



	Years Ended March 31,				Period from February 2, 2016 (Date of Inception) to March 31,
	2018		2017		2016
Share-based compensation expense recognized as:
R&D expenses	$	3,674	$	3,893	$	—
G&A expenses	7,909		4,824		987
Total	$	11,583	$	8,717	$	987

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,				Period from February 2, 2016 (Date of Inception) to March 31,
	2018		2017		2016
Expected common share price volatility	74.4	%	75.5	%	—	%
Expected risk free interest rate	2.04	%	1.57	%	—	%
Expected term, in years	6.22		6.35		—
Expected dividend yield	—	%	—	%	—	%

Fair Value Measurements (Tables)

12 Months Ended

Mar. 31, 2018

Fair Value Disclosures [Abstract]

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



	As of March 31, 2018								As of March 31, 2017

	Level 1		Level 2		Level 3		Balance as of March 31, 2018		Level 1		Level 2		Level 3		Balance as of March 31, 2017
Liabilities:
Takeda warrant liability	$	—	$	—	$	—	$	—	$	—	$	—	$	52	$	52
Total liabilities at fair value	$	—	$	—	$	—	$	—	$	—	$	—	$	52	$	52

Schedule of Significant Unobservable Inputs

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, 2018

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,
	2017			2017			2017			2018			2016 ⁽¹⁾			2016			2016			2017
Total operating expenses	$	21,890		$	30,311		$	41,515		$	47,347		$	17,135		$	6,720		$	9,056		$	22,946
Net loss	$	(23,317	)	$	(29,908	)	$	(41,777	)	$	(48,253	)	$	(18,970	)	$	(34,712	)	$	(8,083	)	$	(21,675	)
Net loss per share attributable to common shareholders - basic and diluted	$	(0.39	)	$	(0.50	)	$	(0.70	)	$	(0.81	)	$	(0.47	)	$	(0.82	)	$	(0.15	)	$	(0.37	)

(1)

Description of Business - Narrative (Details) $ in Millions	12 Months Ended
Description of Business - Narrative (Details) $ in Millions	Mar. 31, 2018 USD ($) segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating segments	1
Number of reporting segments	1
NovaQuest
Other Commitments [Line Items]
Remaining financing commitments \| $	$ 92.0

Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	2 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2018 bank	Mar. 31, 2017 USD ($)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Expected dividend yield	0.00%	0.00%	0.00%
Adjustment to adopt ASU 2016-09			$ 0
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
Credit Concentration Risk
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of banking institutions \| bank		3
Accumulated Deficit
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Adjustment to adopt ASU 2016-09			(122)
Additional Paid in Capital
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Adjustment to adopt ASU 2016-09			122
Accounting Standards Update 2016-09 \| Accumulated Deficit
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Adjustment to adopt ASU 2016-09			(100)
Accounting Standards Update 2016-09 \| Additional Paid in Capital
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Adjustment to adopt ASU 2016-09			$ 100

Summary of Significant Accounting Policies - Schedule of Antidilutive Securities (Details) - shares	2 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	4,836,850	2,654,079
Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	3,549,405	1,525,857
Restricted share awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	1,198,735	1,128,222
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	15,000	0
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	73,710	0

License Agreement - Narrative (Details) - USD ($) $ in Thousands		2 Months Ended	12 Months Ended
	Apr. 29, 2016	Mar. 31, 2016	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 the first commercial sale of relugolix or MVT-602 products	10 years
Ownership percentage to which the warrants entitle Takeda	12.00%
Shares issued to settle the warrant liability to Takeda (in shares)				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, 2018	Mar. 31, 2017
Payables and Accruals [Abstract]
Accrued R&D expenses	$ 25,988	$ 9,737
Accrued compensation-related expenses	2,792	797
Accrued legal expenses	439	481
Accrued other expenses	1,046	963
Total accrued expenses	$ 30,265	$ 11,978

Long-term Debt (Narrative) (Details) - USD ($)	1 Months Ended	12 Months Ended
Long-term Debt (Narrative) (Details) - USD ($)	Oct. 31, 2017	Mar. 31, 2018
Debt Instrument [Line Items]
Equity options, purchase price as a percentage of share price	105.00%
Equity commitment, number of consecutive trading days used for measuring share price	5 days
Equity option	$ 20,000,000
Equity option to be exercised in the current year	$ 10,000,000
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 by NovaQuest (in shares)	138,361
Shares purchased by NovaQuest	$ 2,000,000
Line of Credit \| NovaQuest Securities Purchase Agreement
Debt Instrument [Line Items]
Maximum borrowing commitment	60,000,000
Equity commitment related to note issuance	20,000,000
Minimum borrowing commitment	30,000,000
Debt issued	$ 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		$ 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		500,000
Principal amount funded	$ 25,000,000	$ 15,000,000
Current interest rate		8.75%
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

Long-term Debt (Outstanding Debt Obligations) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Debt Instrument [Line Items]
Principal amount	$ 46,000
Loan payables less unamortized debt issuance costs	43,624	$ 0
Line of Credit \| NovaQuest Securities Purchase Agreement
Debt Instrument [Line Items]
Principal amount	6,000
Less: unamortized debt issuance costs	(854)
Loan payables less unamortized debt issuance costs	5,146
Less: current maturities	0
Long-term loan payable, net of current maturities and unamortized debt issuance costs	5,146
Term Loan \| Hercules Loan Agreement
Debt Instrument [Line Items]
Principal amount	40,000
End of term charge	2,620
Less: unamortized debt issuance costs	(4,142)
Loan payables less unamortized debt issuance costs	38,478
Less: current maturities	0
Long-term loan payable, net of current maturities and unamortized debt issuance costs	$ 38,478

Long-term Debt (Key Assumptions Used to Value Warrants) (Details) - $ / shares	1 Months Ended
	Oct. 31, 2017	Mar. 31, 2018	Sep. 30, 2017
Class of Warrant or Right [Line Items]
Common share price on date of issuance (in USD per share)		$ 15.00	$ 15.00
Tranche 1 \| Common Shares
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
Volatility	73.20%
Risk-free interest rate	2.15%
Expected dividend yield	0.00%
Contractual term (in years)	7 years
Tranche 2 \| Common Shares
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	72.30%
Risk-free interest rate	2.78%
Expected dividend yield	0.00%
Contractual term (in years)	7 years

Long-term Debt Long-term Debt (Maturities of Long-term Debt) (Details) $ in Thousands	Mar. 31, 2018 USD ($)
Debt Disclosure [Abstract]
2019	$ 0
2020	15,779
2021	21,464
2022	5,526
2023	1,846
Thereafter	1,385
Loan payables less unamortized debt issuance costs	$ 46,000

Related Party Transactions - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	2 Months Ended	12 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
RSL and RSI \| RSL and RSI \| Services Agreement
Related Party Transaction [Line Items]
Base salary, fringe benefits, and share-based compensation		$ 0.4	$ 7.7	$ 9.2
RSL \| RSL \| Share-Based Compensation Allocated to the Company by RSL
Related Party Transaction [Line Items]
Base salary, fringe benefits, and share-based compensation		$ 1.0	$ 1.0	$ 4.9
RSL \| RSL \| Option Agreement
Related Party Transaction [Line Items]
Option agreement, term	2 years
Option agreement, purchase price as a percent of payments made by RSL	110.00%

Shareholders' Equity (Deficit) - Narrative (Details) $ / shares in Units, $ in Thousands			1 Months Ended			2 Months Ended	12 Months Ended
	Nov. 01, 2016 USD ($) $ / shares shares	Oct. 18, 2016	Apr. 30, 2017 shares	Aug. 31, 2016 shares	Jun. 30, 2016 shares	Mar. 31, 2016 USD ($)	Mar. 31, 2018 USD ($) $ / shares shares	Apr. 30, 2017 shares	Mar. 31, 2017 USD ($) $ / shares shares	Feb. 02, 2016 class
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of classes of shares \| 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 sold, price (in USD per share) \| $ / shares									$ 15.00
Gross proceeds on sale of shares \| $							$ 1,857		$ 199,964
Net proceeds on sale of shares \| $						$ 0	$ 0		$ 202,275
Options granted (in shares)			32,500				2,338,116		1,525,857
Shares issued to settle the warrant liability to Takeda (in shares)								2,343,624	2,339,192
Initial Public Offering
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares sold (in shares)	14,500,000
Shares sold, price (in USD per share) \| $ / shares	$ 15.00
Gross proceeds on sale of shares \| $	$ 217,500
Net proceeds on sale of shares \| $	200,000
Underwriting discounts and commissions \| $	15,200
Offering costs \| $	$ 2,300
Shares issued to settle the warrant liability to Takeda (in shares)									1,977,269
Restricted Share Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)					1,100,000				1,128,222
Shares issued to settle the warrant liability to Takeda (in shares)									153,846
Employee and Non-employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)				600,000
Shares issued to settle the warrant liability to Takeda (in shares)							4,432		208,077

Income Taxes - Loss Before Income Taxes and Related Tax Benefit (Details) - USD ($) $ in Thousands	2 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
Loss before income taxes:
Bermuda	$ (1,657)	$ (6,513)	$ (50,845)
Total loss before income taxes	(1,657)	(143,042)	(83,514)
Current taxes:
Bermuda	0	0	0
Total current tax expense	0	5	134
Deferred taxes:
Bermuda	0	0	0
Total deferred tax benefit	0	208	(208)
Total income tax expense (benefit)	0	213	(74)
United States
Loss before income taxes:
Foreign	0	(7,229)	(2,924)
Current taxes:
Foreign	0	13	125
Deferred taxes:
Foreign	0	208	(208)
Switzerland
Loss before income taxes:
Foreign	0	(129,261)	(29,745)
Current taxes:
Foreign	0	0	0
Deferred taxes:
Foreign	0	0	0
Other
Loss before income taxes:
Foreign	0	(39)	0
Current taxes:
Foreign	0	(8)	9
Deferred taxes:
Foreign	$ 0	$ 0	$ 0

Income Taxes - Effective Income Tax Reconciliation (Details) - USD ($) $ in Thousands	2 Months Ended	12 Months Ended
	Mar. 31, 2016	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	0	(14,802)	(7,592)
Valuation allowance	0	13,966	7,378
Tax reform	0	1,049	0
Other	0	0	140
Total income tax expense (benefit)	$ 0	$ 213	$ (74)
Effective Income Tax Rate Reconciliation, Percent
Income tax benefit at Bermuda statutory rate	0.00%	0.00%	0.00%
Foreign rate differential	0.00%	10.35%	9.09%
Valuation allowance	0.00%	(9.77%)	(8.83%)
Tax reform	0.00%	(0.73%)	0.00%
Other	0.00%	0.00%	(0.17%)
Total income tax expense (benefit)	0.00%	(0.15%)	0.09%

Income Taxes - Narrative (Details) - USD ($) $ in Thousands	2 Months Ended	12 Months Ended
Income Taxes - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Effective income tax rate	0.00%	(0.15%)	0.09%
Income tax receivable		$ 1,000	$ 105
Operating Loss Carryforwards [Line Items]
Deferred tax assets valuation allowance		21,367	$ 7,401
Switzerland
Operating Loss Carryforwards [Line Items]
Net operating losses		155,500
Ireland
Operating Loss Carryforwards [Line Items]
Net operating losses		23
United Kingdom
Operating Loss Carryforwards [Line Items]
Net operating losses		6,700
United States \| Research and Development Credit Carryforward
Operating Loss Carryforwards [Line Items]
Credit carryforwards		$ 2,900

Income Taxes - Deferred Taxes (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Deferred tax assets:
Research tax credits	$ 2,948	$ 163
Net operating loss	16,045	6,019
Share-based compensation	2,380	1,382
Other	169	300
Subtotal	21,542	7,864
Valuation allowance	(21,367)	(7,401)
Deferred tax liabilities:
Depreciation	(175)	(255)
Total deferred tax assets	$ 0	$ 208

Share-Based Compensation - Narrative (Details) - USD ($)		1 Months Ended				2 Months Ended	12 Months Ended
	Apr. 01, 2017	Apr. 30, 2017	Sep. 30, 2016	Aug. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested options (in shares)							502,361	28,406
Options vested during period (in shares)						0
Unrecognized share-based compensation							$ 33,700,000
Unrecognized share-based compensation, period for recognition							3 years 1 month 28 days
Options granted (in shares)		32,500					2,338,116	1,525,857
Exercise price of options granted in period (in USD per share)							$ 12.50
Fair value of underlying common shares (in USD per share)							15.00		$ 15.00
Weighted-average grant date fair value per share of options granted (in USD per share)						$ 0.00	$ 8.35	$ 11.90
RSL \| RSL \| Share-Based Compensation Allocated to the Company by RSL
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation						$ 1,000,000	$ 1,000,000	$ 4,900,000
Employee and Non-employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)				600,000
Weighted-average grant date fair value per share of options granted (in USD per share)				$ 13.44
Employee and Non-employee Stock Option \| Principal Owner
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Threshold percentage of total voting power of company							10.00%
Exercise price as a percentage of fair value							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)						0	$ 2,500,000	$ 0
Awards granted (in shares)					1,100,000			1,128,222
Fair value of awards granted (in USD per share)					$ 5.10
Restricted Share Awards \| Originally reported
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of awards granted (in USD per share)					$ 1.52
Non-employee Stock Option \| RSI Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)				100,000
Non-employee Stock Option \| RSI Employees \| Stock Options Granted to Non-Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)								100,000
Exercise price of options granted in period (in USD per share)								$ 2.41
Share-based compensation						$ 0	300,000	$ 400,000
Unrecognized compensation expense, period for recognition, related to options for non-employees							$ 100,000
Unrecognized compensation expense, period for recognition, related to options for non-employees, period for recognition							2 years 4 months 17 days
Non-employee Stock Option \| RSI Employees \| Originally reported
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of options granted in period (in USD per share)				$ 2.38
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)			600,000
Weighted-average grant date fair value per share of options granted (in USD per share)			$ 12.78
Options \| Originally reported
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of options granted in period (in USD per share)			$ 4.00
Restricted Stock Units \| Principal Executive Officer \| RSL RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation							$ 0	$ 0
Unrecognized compensation cost related to restricted stock units							$ 900,000
Restricted Stock Units \| Principal Executive Officer \| RSL \| RSL RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)								66,845
Requisite service period							8 years
2016 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for grant (in shares)					4,500,000		1,700,000
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	1 Months Ended	2 Months Ended	12 Months Ended
	Apr. 30, 2017	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
Number of Options
Beginning balance (in shares)	1,525,857		1,525,857
Granted (in shares)	32,500		2,338,116	1,525,857
Exercised (in shares)			(15,195)
Forfeited (in shares)			(299,373)
Ending balance (in shares)			3,549,405	1,525,857
Weighted Average Exercise Price
Beginning balance (in USD per share)	$ 5.06		$ 5.06
Granted (in USD per share)			12.50
Exercised (in USD per share)			2.38
Forfeited (in USD per share)			6.64
Ending balance (in USD per share)			9.84	$ 5.06
Weighted Average Grant Date Fair Value
Beginning balance (in USD per share)	$ 11.90		11.90
Granted (in USD per share)		$ 0.00	8.35	11.90
Exercised (in USD per share)			12.75
Forfeited (in USD per share)			11.35
Ending balance (in USD per share)			$ 9.60	$ 11.90
Options Vested and Expected to Vest
Number of Options (in shares)			3,549,405
Weighted Average Exercise Price (in USD per share)			$ 9.84
Weighted Average Grant Date Fair Value (in USD per share)			$ 9.60
Weighted Average Remaining Contractual Life			9 years 7 days
Aggregate Intrinsic Value (in thousands)			$ 40,557
Additional Information
Options outstanding, Weighted Average Remaining Contractual Life			9 years 7 days
Options outstanding, Aggregate Intrinsic Value			$ 40,557
Options exercisable, Number of Options (in shares)			502,361	28,406
Options exercisable, Weighted Average Exercise Price (in USD per share)			$ 4.88
Options exercisable, Weighted Average Grant Date Fair Value (in USD per share)			$ 11.95
Options exercisable, Weighted Average Remaining Contractual Life			8 years 5 months 26 days
Options exercisable, Aggregate Intrinsic Value			$ 8,235

Share-Based Compensation - Additional Information for Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	2 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Intrinsic value of options exercised	$ 0	$ 181	$ 0
Grant date fair value of options vested	$ 0	$ 5,831	$ 350
Weighted-average grant date fair value per share of options granted (in USD per share)	$ 0.00	$ 8.35	$ 11.90

Share-Based Compensation - Restricted Share Awards and Restricted Stock Units Activity (Details) - Restricted Share Awards and Restricted Stock Units	12 Months Ended
	Mar. 31, 2018 $ / shares shares
Number of shares
Beginning balance (in shares) \| shares	1,128,222
Granted (in shares) \| shares	579,111
Vested (in shares) \| shares	(493,598)
Ending balance (in shares) \| shares	1,213,735
Weighted Average Grant Date Fair Value
Beginning balance (in USD per share) \| $ / shares	$ 5.10
Granted (in USD per share) \| $ / shares	5.10
Vested (in USD per share) \| $ / shares	14.10
Ending balance (in USD per share) \| $ / shares	$ 9.39

Share-Based Compensation - Share-based Compensation Expense (Details) - USD ($) $ in Thousands	2 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	$ 987	$ 11,583	$ 8,717
R&D expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	0	3,674	3,893
G&A expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	$ 987	$ 7,909	$ 4,824

Share-Based Compensation - Schedule of Fair Value Assumptions for Stock Options (Details)	2 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected common share price volatility	0.00%	74.40%	75.50%
Expected risk free interest rate	0.00%	2.04%	1.57%
Expected term, in years	0 years	6 years 2 months 18 days	6 years 4 months 5 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) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Apr. 29, 2016
Liabilities:
Takeda warrant liability			$ 5,400
Fair Value, Measurements, Recurring
Liabilities:
Takeda warrant liability	$ 0	$ 52
Total liabilities at fair value	0	52
Fair Value, Measurements, Recurring \| Level 1
Liabilities:
Takeda warrant liability	0	0
Total liabilities at fair value	0	0
Fair Value, Measurements, Recurring \| Level 2
Liabilities:
Takeda warrant liability	0	0
Total liabilities at fair value	0	0
Fair Value, Measurements, Recurring \| Level 3
Liabilities:
Takeda warrant liability	0	52
Total liabilities at fair value	$ 0	$ 52

Fair Value Measurements - Schedule of Significant Unobservable Inputs (Details) - Fair Value, Measurements, Recurring - Warrant Liability - Level 3	12 Months Ended
	Mar. 31, 2018
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Probability of a successful equity financing	2.00%
Annualized equity volatility	73.40%
Risk-free interest rate	0.74%

Fair Value Measurements - Schedule of Changes in Fair Value of Liabilities (Details) - Warrant Liability - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
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)	2 Months Ended	12 Months Ended
	Mar. 31, 2016 USD ($)	Mar. 31, 2018 USD ($) ft²	Mar. 31, 2017 USD ($)
Property Subject to or Available for Operating Lease [Line Items]
2019		$ 1,347,000
2020		2,009,000
2021		2,063,000
2022		2,127,000
2023		2,200,000
Thereafter		7,650,000
Total minimum operating lease payments		17,396,000
Rent expense	$ 0	$ 900,000	$ 300,000
Brisbane, California Office Space [Member]
Property Subject to or Available for Operating Lease [Line Items]
Area leased (in sq ft) \| ft²		40,232
Extension term		7 years

Selected Quarterly Data (Unaudited) - Schedule of Quarterly Data (Details) - USD ($) $ / shares in Units, $ in Thousands		2 Months Ended	3 Months Ended								12 Months Ended
	Apr. 29, 2016	Mar. 31, 2016	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2018	Mar. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Total operating expenses		$ 1,657	$ 47,347	$ 41,515	$ 30,311	$ 21,890	$ 22,946	$ 9,056	$ 6,720	$ 17,135	$ 141,063	$ 55,857
Net loss		$ (1,657)	$ (48,253)	$ (41,777)	$ (29,908)	$ (23,317)	$ (21,675)	$ (8,083)	$ (34,712)	$ (18,970)	$ (143,255)	$ (83,440)
Net loss per share attributable to common shareholders - basic and diluted (in USD per share)		$ (0.04)	$ (0.81)	$ (0.70)	$ (0.50)	$ (0.39)	$ (0.37)	$ (0.15)	$ (0.82)	$ (0.47)	$ (2.41)	$ (1.70)
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
Shares issued to Takeda under the Takeda license agreement (in shares)	5,077,001
Takeda warrant liability	$ 5,400

Subsequent Events (Details) - USD ($)		1 Months Ended			3 Months Ended
Subsequent Events (Details) - USD ($)	Apr. 02, 2018	May 31, 2018	Apr. 30, 2018	Oct. 31, 2017	Jun. 30, 2018
Private Placement
Subsequent Event [Line Items]
Number of shares issued (in shares)				138,361
Net proceeds from sale of shares				$ 2,000,000
RSL \| Private Placement \| Subsequent Event
Subsequent Event [Line Items]
Number of shares issued (in shares)	1,110,015
Price of shares (in USD per share)	$ 20.27
Gross proceeds from sale of shares			$ 22,500,000
Cowen and Company, LLC \| Private Placement \| Subsequent Event
Subsequent Event [Line Items]
Aggregate offering price	$ 100,000,000
Cowen and Company, LLC \| Private Placement \| Scenario, Forecast \| Subsequent Event
Subsequent Event [Line Items]
Number of shares issued (in shares)					2,767,129
Price of shares (in USD per share)					$ 21.47
Net proceeds from sale of shares					$ 57,600,000
Commercial Manufacturing and Supply Agreement with Takeda \| Subsequent Event
Subsequent Event [Line Items]
Agreement term		5 years
Automatic renewal term		1 year
Termination notice term		12 months
Termination notice term, uncured material breach		90 days
Termination notice term, open purchase orders filed		180 days

Consolidated Statements of Shareholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Stockholders' Equity [Abstract]
Shares sold, price (in USD per share)		$ 15.00
Underwriting discounts and commissions and offering expenses	$ 100	$ 17,536