CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) - USD ($)	3 Months Ended
	Jul. 31, 2015	Jul. 31, 2014
REVENUES:
Contract manufacturing revenue	$ 9,379,000	$ 5,496,000
License revenue	292,000	0
Total revenues	9,671,000	5,496,000
COSTS AND EXPENSES:
Cost of contract manufacturing	4,608,000	3,583,000
Research and development	13,918,000	10,201,000
Selling, general and administrative	4,899,000	4,883,000
Total costs and expenses	23,425,000	18,667,000
LOSS FROM OPERATIONS	(13,754,000)	(13,171,000)
OTHER INCOME (EXPENSE):
Interest and other income	31,000	42,000
NET LOSS	(13,723,000)	(13,129,000)
COMPREHENSIVE LOSS	(13,723,000)	(13,129,000)
Series E preferred stock accumulated dividends	(1,378,000)	(1,028,000)
NET LOSS ATTRIBUTABLE TO COMMON STOCKHOLDERS	$ (15,101,000)	$ (14,157,000)
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING	197,317,374	179,118,255
BASIC AND DILUTED LOSS PER COMMON SHARE	$ (.08)	$ (.08)