Share-based compensation (Tables)

3 Months Ended

Mar. 31, 2021

Share-based compensation

Schedule of share based compensation expense

The Company recorded share‑based compensation expense in the following expense categories of its condensed consolidated statements of operations and comprehensive loss (in thousands):

	Three Months Ended
	March 31,
	2021		2020
Research and development expenses	$	1,211	$	675
General and administrative expenses		2,610		1,446
	$	3,821	$	2,121

Schedule of share option activity

				Weighted
		Weighted		Average	Aggregate
	Number of	Average		Contractual	Intrinsic
	Shares	Exercise Price		Term	Value
				(in years)	(in thousands)
Outstanding as of December 31, 2020	3,736,663	$	10.51	8.54	$	27,553
Granted	1,297,999		18.74	—		—
Exercised	(63,545)		4.47	—		—
Forfeited	(20,509)		15.89	—		—
Outstanding as of March 31, 2021	4,950,608	$	12.73	8.69	$	80,172
Vested and expected to vest as of March 31, 2021	4,950,608	$	12.73	8.69	$	80,172
Options exercisable as of March 31, 2021	2,018,352	$	9.87	8.18	$	39,782

Schedule of assumptions used to determine the fair value of share options granted

	Three Months Ended
	March 31,
	2021		2020
Risk-free interest rate	0.5	%	1.6	%
Expected volatility	79.5	%	73.7	%
Expected dividend yield	—		—
Expected term (in years)	5.95		5.95