4. PROPERTY AND EQUIPMENT

9 Months Ended

Jan. 31, 2018

Property, Plant and Equipment [Abstract]

PROPERTY AND EQUIPMENT

Property and equipment is recorded at cost, less accumulated depreciation and amortization. Depreciation and amortization are computed using the straight-line method over the estimated useful lives of the related asset, generally ranging from three to ten years. Amortization of leasehold improvements is calculated using the straight-line method over the shorter of the estimated useful life of the asset or the remaining lease term. Construction-in-progress, which represents direct costs related to the construction of various equipment and leasehold improvements associated with our manufacturing facilities, are not depreciated until the asset is completed and placed into service. No interest was incurred or capitalized as construction-in-progress as of January 31, 2018.

Property and equipment, net, consists of the following:

	January 31, 2018			April 30, 2017
Leasehold improvements	$	20,579,000		$	20,098,000
Laboratory equipment		10,683,000			10,777,000
Furniture, fixtures, office equipment and software		4,688,000			4,499,000
Construction-in-progress		2,558,000			2,841,000
Total property and equipment		38,508,000			38,215,000
Less accumulated depreciation and amortization		(12,183,000	)		(11,700,000	)
Total property and equipment, net	$	26,325,000		$	26,515,000

Depreciation and amortization expense for the three and nine months ended January 31, 2018 was $645,000 and $1,945,000, respectively. Depreciation and amortization expense for the three and nine months ended January 31, 2017 was $631,000 and $1,850,000, respectively.