Share-Based Compensation Plans (Tables)

12 Months Ended

Apr. 30, 2023

Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]

Schedule of Stock Option Valuation Assumptions

	Fiscal year ended April 30,
	2023			2022
Risk-free interest rate		3.5	%		1.5	%
Expected dividend yield		0.0	%		0.0	%
Expected life (in years)		5.5			5.5
Expected volatility		109.0	%		121.9	%

Schedule of Stock Option Activity

A summary of stock options under our Stock Incentive Plans is detailed in the following table.

	Shares Underlying Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (In Years)
Outstanding as of April 30, 2022		1,110,356		$	2.34		9.2
Granted		601,089		$	0.68
Exercised		—		$	—
Cancelled/forfeited		(182,165	)	$	1.59
Expired		(95	)	$	511.12
Outstanding as of April 30, 2023		1,529,185		$	1.75		8.8
Exercisable as of April 30, 2023		513,077		$	3.22		7.7

Schedule of Non-vested Restricted Stock Activity

A summary of unvested restricted stock units under our stock incentive plans is as follows:

	Number of Shares			Weighted Average Price per Share
Issued and unvested at April 30, 2022		827,764		$	1.41
Granted		1,608,681		$	0.75
Vested and issued		(399,429	)	$	1.38
Cancelled/forfeited		(51,022	)	$	1.32
Issued and unvested at April 30, 2023		1,985,994		$	0.89

Performance Stock Options [Member]

Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]

Schedule of Stock Option Activity

A summary of performance stock options under our stock incentive plans is detailed in the following table.

	Shares Underlying Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (In Years)
Outstanding as of April 30, 2022		210,122		$	2.20		8.8
Granted		—		$	—
Exercised		—		$	—
Cancelled/forfeited		(143,455	)	$	2.93
Outstanding as of April 30, 2023		66,667		$	0.62		8.1
Exercisable as of April 30, 2023		—		$	—