Share-Based Payment Awards (Tables)

6 Months Ended

Jun. 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 six months ended June 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		1,643,300			10.43
Exercised		(4,223	)		9.44
Forfeited		(98,470	)		11.98
Expired		(6,000	)		21.00
Outstanding at June 30, 2022		4,052,287		$	14.14		8.28	$	72,444
Exercisable at June 30, 2022		1,306,830		$	19.82		6.26	$	27,575

Schedule of Key Assumptions Used

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

Option life (in years)	5.50 - 6.08
Stock volatility	76% - 78%
Risk-free interest rate	1.46% - 3.36%
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 six months ended June 30, 2022 (in thousands except per share amount):

	Six Months
	Ended
	June 30, 2022
Weighted average grant date fair value per share	$	7.03
Total cash received from exercise of stock options		40
Total intrinsic value of stock options exercised		13

Summary of Restricted Stock Unit Activity

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

				Weighted
	Number of			Average
	Restricted			Grant Date
	Stock Units			Fair Value
Nonvested at January 1, 2022		291,575		$	13.19
Granted		409,500			10.09
Vested		(140,402	)		13.44
Forfeited		(18,793	)		11.31
Nonvested at June 30, 2022		541,880		$	10.85

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 six months ended June 30, 2022 and 2021, respectively, as follows (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2022		2021		2022		2021
Compensation expense included in:
Research and development	$	2,011	$	255	$	3,485	$	518
Sales and marketing		496		241		905		481
General and administrative		1,633		684		3,227		1,169
	$	4,140	$	1,180	$	7,617	$	2,168