Stock-Based Compensation

9 Months Ended

Sep. 30, 2024

Note 4 - Stock-Based Compensation

Under the fair value recognition provisions of U.S. GAAP for accounting for stock-based compensation the Company measures stock-based compensation expense at the grant date based on the fair value of the award and recognizes the compensation expense over the requisite service period, which is generally the vesting period.

The following table presents the classification of stock-based compensation expense recognized for the periods below:

	Three months ended September 30				Nine months ended September 30
(in thousands)	2024		2023		2024		2023
Selling, general and administrative expense	$	99	$	133	$	363	$	484
Research and development expense		2		2		11		29
Total stock-based compensation expense	$	101	$	135	$	374	$	513

During the three months ended September 30, 2024, and 2023, under the 2017 Equity Incentive Plan, and the 2021 Inducement Plan, the Company granted zero and 532 stock options, respectively, to its directors, officers and employees. During the nine months ended September 30, 2024 and 2023, the Company granted 1,264 and 3,544 stock options, respectively, to its directors, officers and employees. Vesting generally occurs over an immediate to 48-month period based on a time-of-service condition. The weighted-average grant date fair value of the stock-options issued during the three months ended September 30, 2024 and 2023 was zero and $62.65 per share, respectively. The weighted-average grant date fair value of the stock options issued during the nine months ended September 30, 2024 and 2023 was $24.14 and $226.26 per share, respectively.

The total number of stock options outstanding as of September 30, 2024 and September 30, 2023 was 3,890 and 3,101, respectively.

The weighted-average assumptions used in the Black-Scholes option-pricing model are as follows for the stock options granted during the three and nine months ended September 30, 2024 and 2023:

	Three months ended						Nine months ended
	September 30						September 30
	2024			2023			2024			2023
Expected volatility		138.70	%		131.06	%		138.70	%		152.59	%
Expected Life of options (years)		5.51			6.25			5.51			6.19
Expected dividend yield		0	%		0	%		0	%		0	%
Risk-free interest rate		3.94	%		4.29	%		3.94	%		4.16	%

During the three months ended September 30, 2024 and 2023, 420 and 69 stock options vested, respectively, and 102 and 595 stock options were expired or forfeited during these periods, respectively. During the nine months ended September 30, 2024 and 2023, 1,767 and 129 stock options vested, respectively, and 465 and 680 stock options were expired or forfeited during these periods, respectively. During the three and nine months ended September 30, 2024 and 2023, no options were exercised.