Share-Based Payments

The Company has in place a 2010 Equity Incentive Plan and a 2008 Equity Incentive Plan. In general, these plans provide for stock-based compensation in the form of (i) Non-statutory Stock Options; (ii) Restricted Stock Awards; and (iii) Stock Appreciation Rights to the Company’s employees, directors and non-employees. The plans also provide for limits on the aggregate number of shares that may be granted, the term of grants and the strike price of option awards.

Stock-based compensation in the amount of $229,000 and $335,000 was recognized for the three months ended January 31, 2019 and 2019, respectively. Stock-based compensation in the amount of $437,000 and $498,000 was recognized for the nine months ended January 31, 2020 and 2019, respectively. Included in 2019 stock-based compensation expense for the nine months January 31, 2019 under general and administrative line item is $7,500 for the issuance of common stock as compensation for services performed. Stock-based compensation expense was recognized as follows (table in thousands):



	Three Months Ended January 31,				Nine Months Ended January 31,
	2020		2019		2020		2019
General and administrative	$	110	$	251	$	281	$	326
Sales and marketing	95		53		144		100
Research and development	4		4		9		13
Cost of oncology services	20		27		3		59
Total stock-based compensation expense	$	229	$	335	$	437	$	498

Stock Option Grants

Black-Scholes assumptions used to calculate the fair value of options granted during the three and nine months ended January 31, 2020 and 2019 were as follows:



	Three Months Ended January 31,		Nine Months Ended January 31,
	2020	2019	2020	2019
Expected term in years	3-6	3-6	3-6	3-6
Risk-free interest rates	1.57%-1.80%	2.57%-3.00%	1.57%-1.80%	2.57%-3.00%
Volatility	69.14%-70.99%	64.55%-84.91%	69.14%-71.11%	64.55%-84.91%
Dividend yield	—%	—%	—%	—%

The weighted average fair value of stock options granted during the three months ended January 31, 2020 and 2019 was $2.56 and $5.76, respectively, and $3.09 and $6.03 for the nine months ended January 31, 2020 and 2019, respectively.

The Company’s stock options activity for the nine months ended January 31, 2020 was as follows:



	Directors and Employees		Non- Employees		Total		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
Outstanding, May 1, 2019	2,373,626		50,000		2,423,626		$	3.19	5.3	$	14,557,000
Granted	219,833		—		219,833		5.29
Exercised	(203,736	)	—		(203,736	)	2.10
Forfeited	(41,875	)	—		(41,875	)	7.99
Canceled	(4,583	)	—		(4,583	)	11.90
Expired	(70,001	)	(6,668	)	(76,669	)	8.04

Outstanding, January 31, 2020	2,273,264		43,332		2,316,596		3.22		5.21	$	10,594,000

Vested and expected to vest as of January 31, 2020	2,273,264		43,332		2,316,596		3.22		5.21	$	10,594,000

Exercisable as of January 31, 2020	1,896,534		17,501		1,914,035		2.72		4.53	$	9,695,000

Stock Purchase Warrants

As of January 31, 2020 and April 30, 2019, the Company had warrants outstanding for the purchase of 1,669,773 and 1,671,440, respectively, shares of its common stock, all of which were exercisable. Activity related to these warrants, which expire at various dates through March 2020, is summarized as follows:



	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
Outstanding, May 1, 2019	1,671,440		$	6.20	0.9	$	5,730,000
Granted	—		—		—	—
Exercised	—		—		—	—
Canceled	—		—		—	—
Expired	(1,667	)	4.80		—	—

Outstanding, January 31, 2020	1,669,773		$	5.66	0.1	$	3,225,000