Share-Based Compensation

12 Months Ended

Dec. 31, 2022

Share-based Payment Arrangement [Abstract]

Share-based Compensation

The Company utilizes share-based compensation in the form of stock options, restricted stock, and restricted stock units. The following table summarizes the components of share-based compensation expense for the years ended December 31, 2022 and 2021 ($ in thousands):


	Year Ended December 31,
	2022		2021
Research and development	$	776	$	760
General and administrative	1,860		1,245

Total share-based compensation expense	$	2,636	$	2,005

Total compensation cost related to unvested awards not yet recognized and the weighted-average periods over which the awards are expected to be recognized at December 31, 2022 were as follows ($ in thousands):


	Stock Options		Restricted Stock Units		Restricted Stock
Unrecognized compensation cost	$	1,241	$	113	$	570
Expected weighted-average period in years of compensation cost to be recognized	1.47		2.59		1.65

Total fair value of shares vested and the weighted average estimated fair values of shares granted for the years ended December 31, 2022 and 2021 were as follows ($ in thousands):


	Stock Options
	Year Ended December 31,
	2022		2021
Total fair value of shares vested	$	1,045	$	757
Weighted average estimated fair value of shares granted	1.23		0.91

Valuation Assumptions

The fair value of stock options at the date of grant was estimated using the Black-Scholes option pricing model. The expected volatility is based upon historical volatility of the Company’s stock. The expected term for the options is based upon observation of actual time elapsed between date of grant and exercise of options for all employees.

The range of assumptions made in calculating the fair values of stock options was as follows:


	Stock Options
	Year Ended December 31,
	2022	2021
Expected term - minimum (in years)	6	6
Expected term - maximum (in years)	6	6
Expected volatility - minimum	76%	79%
Expected volatility - maximum	78%	84%
Weighted Average volatility	76%	81%
Expected dividend yield	—	—
Risk-free interest rate - minimum	1.62%	0.63%
Risk-free interest rate - maximum	2.90%	1.16%