2. Summary of Significant Accounting Policies (Tables)

3 Months Ended

Jul. 31, 2019

Accounting Policies [Abstract]

Disaggregation of revenue

	Three Months Ended July 31,
	2019		2018
Manufacturing revenue	$	12,908	$	10,300
Process development revenue		2,346		2,289
Total revenues	$	15,254	$	12,589

Schedule of property and equipment

	July 31, 2019			April 30, 2019
Leasehold improvements	$	20,574		$	20,574
Laboratory and manufacturing equipment		12,983			12,858
Computer equipment and software		4,662			4,644
Furniture, fixtures and office equipment		528			528
Construction-in-progress		3,001			1,590
Total property and equipment, gross	$	41,748		$	40,194
Less: accumulated depreciation and amortization		(15,295	)		(14,569	)
Total property and equipment, net	$	26,453		$	25,625