Condensed Consolidated Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Mar. 31, 2019		22,779,891
Beginning balance at Mar. 31, 2019	$ 56,213	$ 0	$ 741,318	$ (686,016)	$ 911
Increase (Decrease) in Shareholders' Equity (Deficit)
Issuance of shares upon exercise of stock options (in shares)		781
Issuance of shares upon exercise of stock options	5		5
Stock-based compensation expense	2,135		2,135
Capital contribution received from Roivant Sciences, Inc.	28		28
Foreign currency translation adjustment	(972)				(972)
Net loss	(28,057)			(28,057)
Ending balance (in shares) at Jun. 30, 2019		22,780,672
Ending balance at Jun. 30, 2019	29,352	$ 0	743,486	(714,073)	(61)
Beginning balance (in shares) at Mar. 31, 2019		22,779,891
Beginning balance at Mar. 31, 2019	56,213	$ 0	741,318	(686,016)	911
Increase (Decrease) in Shareholders' Equity (Deficit)
Foreign currency translation adjustment	(420)
Net loss	(41,941)
Ending balance (in shares) at Sep. 30, 2019		22,791,669
Ending balance at Sep. 30, 2019	17,040	$ 0	744,506	(727,957)	491
Beginning balance (in shares) at Mar. 31, 2019		22,779,891
Beginning balance at Mar. 31, 2019	56,213	$ 0	741,318	(686,016)	911
Increase (Decrease) in Shareholders' Equity (Deficit)
Net loss	(72,600)
Ending balance (in shares) at Mar. 31, 2020		39,526,299
Ending balance at Mar. 31, 2020	61,558	$ 0	820,257	(758,644)	(55)
Beginning balance (in shares) at Jun. 30, 2019		22,780,672
Beginning balance at Jun. 30, 2019	29,352	$ 0	743,486	(714,073)	(61)
Increase (Decrease) in Shareholders' Equity (Deficit)
Issuance of shares upon exercise of stock options (in shares)		10,997
Issuance of shares upon exercise of stock options	81		81
Stock-based compensation expense	891		891
Capital contribution received from Roivant Sciences, Inc.	48		48
Foreign currency translation adjustment	552				552
Net loss	(13,884)			(13,884)
Ending balance (in shares) at Sep. 30, 2019		22,791,669
Ending balance at Sep. 30, 2019	17,040	$ 0	744,506	(727,957)	491
Beginning balance (in shares) at Mar. 31, 2020		39,526,299
Beginning balance at Mar. 31, 2020	61,558	$ 0	820,257	(758,644)	(55)
Increase (Decrease) in Shareholders' Equity (Deficit)
Shares issued for restricted stock units (in shares)		53,653
Shares issued for restricted stock units	0
Shares sold in connection with at-the-market offering, net of brokerage fees and offering expenses of $0.5 million (in shares)		1,393,428
Shares sold in connection with at-the-market offering, net of brokerage fees and offering expenses of $0.5 million	3,930		3,930
Stock-based compensation expense	1,590		1,590
Capital contribution received from Roivant Sciences, Inc.	53		53
Foreign currency translation adjustment	44				44
Net loss	(8,594)			(8,594)
Ending balance (in shares) at Jun. 30, 2020		40,973,380
Ending balance at Jun. 30, 2020	58,581	$ 0	825,830	(767,238)	(11)
Increase (Decrease) in Shareholders' Equity (Deficit)
Brokerage fees and offering expenses	500
Beginning balance (in shares) at Mar. 31, 2020		39,526,299
Beginning balance at Mar. 31, 2020	61,558	$ 0	820,257	(758,644)	(55)
Increase (Decrease) in Shareholders' Equity (Deficit)
Foreign currency translation adjustment	392
Net loss	(18,578)
Ending balance (in shares) at Sep. 30, 2020		47,249,729
Ending balance at Sep. 30, 2020	69,673	$ 0	846,558	(777,222)	337
Beginning balance (in shares) at Jun. 30, 2020		40,973,380
Beginning balance at Jun. 30, 2020	58,581	$ 0	825,830	(767,238)	(11)
Increase (Decrease) in Shareholders' Equity (Deficit)
Shares issued for restricted stock units (in shares)		60,676
Shares issued for restricted stock units	0
Shares sold in connection with at-the-market offering, net of brokerage fees and offering expenses of $0.5 million (in shares)		6,215,673
Shares sold in connection with at-the-market offering, net of brokerage fees and offering expenses of $0.5 million	19,598		19,598
Stock-based compensation expense	1,108		1,108
Capital contribution received from Roivant Sciences, Inc.	22		22
Foreign currency translation adjustment	348				348
Net loss	(9,984)			(9,984)
Ending balance (in shares) at Sep. 30, 2020		47,249,729
Ending balance at Sep. 30, 2020	69,673	$ 0	$ 846,558	$ (777,222)	$ 337
Increase (Decrease) in Shareholders' Equity (Deficit)
Brokerage fees and offering expenses	$ 700