Share-Based Payment Awards (Tables)

9 Months Ended

Sep. 30, 2022

Share-Based Payment Arrangement [Abstract]

Stock Option Activity Under Plan

The following table provides a reconciliation of stock option activity under the Company’s equity incentive plans and for inducement awards for the nine months ended September 30, 2022:

						Weighted
				Weighted		Average
				Average		Remaining		Aggregate
	Number			Exercise		Contractual		Intrinsic
	of Options			Price		Life		Value
						(in years)		(in thousands)
Outstanding at January 1, 2022		2,517,680		$	16.49
Granted		1,783,300			10.32
Exercised		(4,479	)		9.20
Forfeited		(254,300	)		12.89
Expired		(10,536	)		21.17
Outstanding at September 30, 2022		4,031,665		$	13.99		8.08	$	72,129
Exercisable at September 30, 2022		1,381,575		$	19.32		6.17	$	31,793

Schedule of Key Assumptions Used

In determining the grant date fair value of option awards during the nine months ended September 30, 2022, the Company applied the Black-Scholes option pricing model based on the following key assumptions:

Option life (in years)	5.50 - 6.09
Stock volatility	76% - 78%
Risk-free interest rate	1.46% - 3.59%
Expected dividends	0.0%

Summary of Information about Stock Options

The following table summarizes information about employee, non-executive director and external consultant stock options for the nine months ended September 30, 2022 (in thousands except per share amount):

	Nine Months
	Ended
	September 30, 2022
Weighted average grant date fair value per share	$	6.96
Total cash received from exercise of stock options		41
Total intrinsic value of stock options exercised		14

Summary of Restricted Stock Unit Activity

The following table provides a reconciliation of RSU activity under the 2016 Plan for the nine months ended September 30, 2022:

				Weighted
	Number of			Average
	Restricted			Grant Date
	Stock Units			Fair Value
Nonvested at January 1, 2022		291,575		$	13.19
Granted		415,500			10.06
Vested		(140,402	)		13.44
Forfeited		(36,995	)		11.04
Nonvested at September 30, 2022		529,678		$	10.82

Compensation Expense from Stock-Based Payment Awards

The Company’s consolidated statements of comprehensive loss included total compensation expense from stock-based payment awards for the three and nine months ended September 30, 2022 and 2021, respectively, as follows (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Compensation expense included in:
Research and development	$	1,277	$	719	$	4,762	$	1,291
Sales and marketing		290		348		1,195		829
General and administrative		1,632		1,404		4,859		2,519
	$	3,199	$	2,471	$	10,816	$	4,639