7. EQUITY COMPENSATION PLANS

9 Months Ended

Jan. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

EQUITY COMPENSATION PLANS

Stock Incentive Plans

As of January 31, 2018, we had an aggregate of 5,433,646 shares of our common stock reserved for issuance under our stock incentive plans, of which, 3,989,356 shares were subject to outstanding options and 1,444,290 shares were available for future grants of share-based awards.

The following summarizes our stock option transaction activity for the nine months ended January 31, 2018:

Stock Options	Shares		Weighted Average Exercisable Price
Outstanding, May 1, 2017		4,081,548	$	8.77
Granted		679,497	$	4.17
Exercised		(117,019)	$	3.40
Canceled or expired		(654,670)	$	8.42
Outstanding, January 31, 2018		3,989,356	$	8.70

Employee Stock Purchase Plan (ESPP)

We have reserved a total of 2,142,857 shares of our common stock to be purchased under our ESPP, of which 1,303,770 shares remained available to purchase at January 31, 2018, and are subject to adjustment as provided in the ESPP for stock splits, stock dividends, recapitalizations and other similar events. Under the ESPP, we sell shares to participants at a price equal to the lesser of 85% of the fair market value of our common stock at the (i) beginning of a six-month offering period, or (ii) end of the six-month offering period. The ESPP provides for two six-month offering periods each year; the first offering period begins on the first trading day on or after each May 1; the second offering period begins on the first trading day on or after each November 1. During the nine months ended January 31, 2018, 55,966 shares of our common stock were purchased under the ESPP at a purchase price of $3.87 per share.

Share-Based Compensation

Total share-based compensation expense related to share-based awards issued under our equity compensation plans is included in the accompanying unaudited condensed consolidated statements of operations as follows:

	Three Months Ended January 31,				Nine Months Ended January 31,
	2018		2017		2018		2017
Cost of contract manufacturing	$	139,000	$	23,000	$	277,000	$	89,000
Selling, general and administrative		259,000		389,000		589,000		1,183,000
Discontinued operations		14,000		457,000		340,000		1,319,000
Total	$	412,000	$	869,000	$	1,206,000	$	2,591,000
Share-based compensation from:
Stock options	$	374,000	$	815,000	$	1,070,000	$	2,369,000
ESPP		38,000		54,000		136,000		222,000
	$	412,000	$	869,000	$	1,206,000	$	2,591,000

As of January 31, 2018, the total estimated unrecognized compensation cost related to non-vested employee stock options was $2,605,000. This cost is expected to be recognized over a weighted average vesting period of 2.67 years based on current assumptions.