5. PROPERTY AND EQUIPMENT (Tables)

6 Months Ended

Oct. 31, 2018

Property, Plant and Equipment [Abstract]

Schedule of property and equipment

	October 31, 2018			April 30, 2018
Leasehold improvements	$	20,738		$	20,686
Laboratory equipment		12,380			10,258
Furniture, fixtures, office equipment and software		5,159			4,597
Construction-in-progress		1,644			3,310
Total property and equipment		39,921			38,851
Less accumulated depreciation and amortization		(13,642	)		(12,372	)
Total property and equipment, net	$	26,279		$	26,479