Share-Based Payments (Tables)

6 Months Ended

Oct. 31, 2021

Share-based Payment Arrangement [Abstract]

Summary of allocation of share based compensation expense

Stock-based compensation expense was recognized as follows (table in thousands):

	Three Months Ended October 31,				Six Months Ended October 31,
	2021		2020		2021		2020
General and administrative	$	48	$	10	$	219	$	57
Sales and marketing	45		49		96		97
Research and development	8		5		14		9
Cost of oncology services	33		21		85		42
Total stock-based compensation expense	$	134	$	85	$	414	$	205

Summary of valuation assumptions for stock options

Black-Scholes assumptions used to calculate the fair value of options granted during the three and six months ended October 31, 2021 and 2020 were as follows:

	Three Months Ended October 31,			Six Months Ended October 31,
	2021	2020		2021	2020
Expected term in years	—	6		6	6
Risk-free interest rates	—%	0.27%	0	0.82%-—%	0.27%-0.39%
Volatility	—%	72.83%		65.94%-66.21%	72.64%-72.83%
Dividend yield	—%	—%		—%	—%

Summary of stock option activity

The Company’s stock options activity for the six months ended October 31, 2021 was as follows:

	Directors and Employees	Non- Employees	Total	Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
Outstanding, April 30, 2021	1,618,231	35,415	1,653,646	$	3.96	5.42	$	11,384,000
Granted	82,532	3,000	85,532	9.01		9.65
Exercised	(82,078)	—	(82,078)	1.91
Forfeited	(12,500)	—	(12,500)	6.74
Canceled	(4,672)	—	(4,672)	3.36
Expired	—	(5,000)	(5,000)	9.60
Outstanding, October 31, 2021	1,601,513	33,415	1,634,928	4.29		5.27	$	9,246,000
Vested and expected to vest as of October 31, 2021	1,601,513	33,415	1,634,928	4.29		5.27	$	9,246,000
Exercisable as of October 31, 2021	1,296,094	4,584	1,300,678	3.69		4.51	$	8,189,000