Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2020

Stockholders' Equity

Schedule of stock option activity

				Weighted
		Weighted		average	Aggregate
	Number	average		contractual	intrinsic
	of shares	exercise price		term	value
Outstanding at December 31, 2019	3,458,447	$	10.19
Granted	566,815		51.12
Exercised	(60,186)		10.46
Forfeited	(2,343)		13.98
Expired	—		—
Outstanding at March 31, 2020	3,962,733	$	16.04	8.0	$	171,744,639
Vested and expected to vest at March 31, 2020	3,954,064	$	16.07	8.0	$	171,248,106
Exercisable at March 31, 2020	1,958,757	$	7.48	6.4	$	100,572,453

Schedule of RSU activity

				Weighted
		Weighted		average	Aggregate
	Number	average		contractual	intrinsic
	of shares	exercise price		term	value
Outstanding at December 31, 2019	—	$	—
Granted	149,389		45.14
Released	—		—
Forfeited	—		—
Outstanding at March 31, 2020	149,389	$	45.14	4.0	$	8,788,555

Schedule of stock-based compensation expense

	Three months ended March 31,
	2020		2019
Research and development	$	634,375	$	101,701
General and administrative		1,499,155		1,154,609
Total	$	2,133,530	$	1,256,310

Schedule of warrant activity

		Weighted
		average
	Warrants	exercise price
Outstanding at December 31, 2019	69,656	$	7.21
Issued	—		—
Exercised	—		—
Outstanding at March 31, 2020	69,656	$	7.21