Share-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2023

Share-Based Payment Arrangement [Abstract]

Schedule of Outstanding Stock Options

Total outstanding stock options as of September 30, 2023 was as follows:

	Number of shares			Weighted average exercise price
Outstanding at January 1, 2023		8,032,902		$	14.38
Granted		2,306,940		$	11.73
Exercised		(17,450	)	$	2.65
Cancelled or forfeited		(234,801	)	$	14.99
Outstanding at September 30, 2023		10,087,591		$	13.78

Schedule of Fair Value of Stock Options Determined on Grant Date Using Black Scholes Option-Pricing Model

The fair value of stock options, and the assumptions used in the Black Scholes option-pricing model to determine the grant date fair value of stock options granted to employees and non-employees were as follows, presented on a weighted average basis:

	Three Months Ended September 30,						Nine Months Ended September 30,
	2023			2022			2023			2022
Fair value of stock options	$	7.77		$	8.45		$	8.31		$	9.40
Risk-free interest rate		4.36	%		2.89	%		3.71	%		2.09	%
Expected terms (in years)		6.08			6.08			6.01			5.98
Expected volatility		81.73	%		81.20	%		81.49	%		78.82	%
Expected dividend yield		0.00	%		0.00	%		0.00	%		0.00	%

Summary of Total Outstanding Restricted Stock Units

Total outstanding restricted share units as of September 30, 2023 was as follows:

	Number of shares			Weighted average grant date fair value
Outstanding at January 1, 2023		—		$	-
Awarded		626,260		$	12.42
Forfeited		(21,300	)	$	12.42
Outstanding at September 30, 2023		604,960		$	12.42

The fair value of each restricted share unit is estimated on the date of grant based on the fair value of our common shares on that same date.

Schedule of Share-based Compensation Expense

Share-based compensation expense was allocated as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
	(in thousands)
Research and development	$	3,339	$	2,600	$	9,887	$	7,351
General and administrative		3,038		2,453		8,817		7,202
Total share-based compensation expense	$	6,377	$	5,053	$	18,704	$	14,553

Share-based compensation expense by type of award was as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
	(in thousands)
Stock options	$	5,678	$	4,969	$	16,776	$	14,376
Restricted share units		625		—		1,670		—
ESPP		74		84		258		177
Total share-based compensation expense	$	6,377	$	5,053	$	18,704	$	14,553