Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Dec. 31, 2016	Dec. 31, 2016
Operating expenses:
Research and development (includes $1,060 and $2,849 of share-based compensation expense for the three and nine months ended December 31, 2016, respectively)	$ 6,158	$ 24,484
General and administrative (includes $950 and $3,932 of share-based compensation expense for the three and nine months ended December 31, 2016, respectively)	2,898	8,427
Total operating expenses	9,056	32,911
Other income (expense):
Changes in the fair value of the warrant liability	1,002	(28,815)
Loss before provision for income tax expense	(8,054)	(61,726)
Income tax expense	29	40
Net loss	(8,083)	(61,766)
Comprehensive loss	$ (8,083)	$ (61,766)
Net loss per common share — basic and diluted (in USD per share)	$ (0.15)	$ (1.34)
Weighted average common shares outstanding — basic and diluted (in shares)	54,447,203	45,929,021