Warrants

3 Months Ended

Mar. 31, 2022

Equity [Abstract]

Warrants

As of March 31, 2022, the following warrants for common stock were issued and outstanding:

Issue date	Expiration date	Exercise price		Number of warrants outstanding
January 11, 2017	None	$	0.001	3,578,036
November 20, 2017	None	$	0.001	3,669,360
June 11, 2018	None	$	0.001	358,415
				7,605,811

Sale of Common Stock    

In November 2021, the Company sold 3,448,275 shares of its common stock at a public offering price of $145.00 per share. After deducting underwriter discounts, commissions and estimated offering expenses, the Company received net proceeds from the transaction of $474.7 million.

At the Market Facility

On July 2, 2020, the Company entered into a sales agreement pursuant to which the Company may, from time to time, sell shares of the Company's common stock, par value $0.001 per share, having an aggregate offering price of up to $200.0 million. On July 2, 2021, the Company entered into an amended and restated sales agreement pursuant to which the Company may, from time to time, sell shares of the Company’s common stock, par value $0.001 per share, having an aggregate offering price of up to $500.0 million. As of March 31, 2022, the Company has not offered or sold any shares of common stock pursuant to this sales agreement.

Share-based Compensation

Total share-based compensation expense by statement of operations and comprehensive loss classification is presented below (in thousands):

	Three Months Ended March 31,
	2022		2021
Research and development expense	$	26,260	$	14,534
General and administrative expense	16,645		10,188
	$	42,905	$	24,722

During the three months ended March 31, 2022, 154,572 shares of common stock were issued under the Company’s equity incentive plans, generating net proceeds of $2.5 million. During the three months ended March 31, 2021, 312,903 shares of common stock were issued under the Company’s equity incentive plans, generating net proceeds of $9.9 million.