Share-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2023

Share-Based Payment Arrangement [Abstract]

The following table summarizes the stock option activity during the six months ended June 30, 2023:


	Stock Option Shares	Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in Years)	Aggregate Intrinsic Value (in thousands)
Outstanding, January 1, 2023	2,990,423	$	19.28	8.59	$	2,849
Granted	1,680,709	9.01
Exercised	(35,633)	2.12
Expired/cancelled	(550,133)	21.04
Outstanding as of June 30, 2023	4,085,366	$	15.50	8.66	$	960
Options exercisable as of June 30, 2023	1,131,691	$	17.40	7.31	$	895
Vested and expected to vest as of June 30, 2023	4,085,366	$	15.50	8.66	$	960

Summary of Recognized Compensation Cost Related to Employee and Non-employee Stock-Based Compensation Activity

The Company recognized the following compensation cost related to employee and non-employee share-based compensation activity for the periods presented (in thousands):


	Three Months Ended June 30,				Six Months Ended June 30,
	2023		2022		2023		2022
Selling, general and administrative	$	1,846	$	1,551	$	3,486	$	2,652
Research and development	1,208		684		2,308		1,364
Total	$	3,054	$	2,235	$	5,794	$	4,016

Stock Options Valuation Assumptions

The calculation was based on the following assumptions:


	Three Months Ended June 30,		Six Months Ended June 30,
	2023	2022	2023	2022
Weighted average grant date fair value (per share)	$6.07	$12.08	$7.95	$12.08
Risk-free interest rate	3.47% - 3.85%	2.53% - 3.38%	3.42% - 4.17%	1.46% - 3.38%
Expected volatility	91.54% - 99.29%	85.91% - 87.06%	89.94% - 99.29%	85.91% - 87.06%
Expected term (in years)	5.50 - 6.08	5.50 - 6.08	5.50 - 6.08	5.50 - 6.08
Expected dividend yield	—	—	—	—