CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) - USD ($)	3 Months Ended		6 Months Ended
	Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2016	Oct. 31, 2015
REVENUES:
Contract manufacturing revenue	$ 23,370,000	$ 9,523,000	$ 28,979,000	$ 18,902,000
License revenue	0	0	0	292,000
Total revenues	23,370,000	9,523,000	28,979,000	19,194,000
COSTS AND EXPENSES:
Cost of contract manufacturing	15,441,000	4,741,000	18,503,000	9,349,000
Research and development	7,022,000	14,190,000	15,591,000	28,108,000
Selling, general and administrative	4,984,000	4,416,000	10,044,000	9,315,000
Total costs and expenses	27,447,000	23,347,000	44,138,000	46,772,000
LOSS FROM OPERATIONS	(4,077,000)	(13,824,000)	(15,159,000)	(27,578,000)
Interest and other income	21,000	626,000	46,000	657,000
NET LOSS	(4,056,000)	(13,198,000)	(15,113,000)	(26,921,000)
COMPREHENSIVE LOSS	(4,056,000)	(13,198,000)	(15,113,000)	(26,921,000)
Series E preferred stock accumulated dividends	(1,442,000)	(1,380,000)	(2,477,000)	(2,413,000)
NET LOSS ATTRIBUTABLE TO COMMON STOCKHOLDERS	$ (5,498,000)	$ (14,578,000)	$ (17,590,000)	$ (29,334,000)
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING - Basic and Diluted	244,815,767	203,942,411	242,205,428	200,629,892
BASIC AND DILUTED LOSS PER COMMON SHARE	$ (.02)	$ (.07)	$ (.07)	$ (.15)