Shareholders' Equity

9 Months Ended

Sep. 30, 2020

Share-based Payment Arrangement [Abstract]

Shareholders' Equity

Warrants 

As of September 30, 2020, 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	4,533,224
November 20, 2017	None	$	0.001	4,137,999
June 11, 2018	None	$	0.001	421,650
				9,092,873

No warrants were exercised during the three months ended September 30, 2020. During the three months ended September 30, 2019, 725,008 warrants for shares of the Company's common stock were exercised via cashless exercise, resulting in the issuance of 725,000 shares of common stock. During the nine months ended September 30, 2020, 600,006 warrants for shares of the Company's common stock were exercised via cashless exercise, resulting in the issuance of 600,000 shares of common stock. During the nine months ended September 30, 2019, 2,125,033 warrants for shares of the Company's common stock were exercised via cashless exercise, resulting in the issuance of 2,125,000 shares of common stock.

Shareholders' Equity

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. As of September 30, 2020, the Company has not offered or sold any shares of common stock pursuant to this sales agreement.

Sale of Common Stock    

In January 2020, the Company sold 3,538,462 shares of its common stock at a public offering price of $97.50 per share. After deducting underwriter discounts, commissions and offering expenses, the Company received net proceeds from the transaction of $324.0 million.

In June 2019, the Company sold 2,415,000 shares of its common stock at a public offering price at $97.00 per share. After deducting underwriter discounts, commissions and offering expenses, the Company received net proceeds from the transaction of $219.9 million.    

In January 2019, the Company sold 1,854,838 shares of its common stock at a public offering price of $62.00 per share. After deducting underwriter discounts, commissions and offering expenses, the Company received net cash proceeds from the transaction of $107.9 million.

Share-based Compensation

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

	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Research and development expense	$	12,556	$	8,648	$	35,861	$	20,416
General and administrative expense	9,195		6,458		28,243		18,410
	$	21,751	$	15,106	$	64,104	$	38,826

During the three and nine months ended September 30, 2020, 272,158 and 1,092,468 shares were issued under our equity incentive plans, generating net proceeds of $12.4 million and $36.3 million, respectively. During the three and nine months ended September 30, 2019, 91,257 and 424,144 shares were issued under our equity incentive plans, generating net proceeds of $1.1 million and $5.4 million, respectively.

Disgorgement Proceeds

In January 2019, the Company received a payment of $1.1 million, representing a disgorgement of short-swing profits from the sale of common stock by a beneficial owner pursuant to Section 16(b) of the Securities Exchange Act of 1934, as amended. In January 2020, the Company received an immaterial disgorgement of short-swing profits. The Company recognized these proceeds as a capital contribution from shareholders and reflected a corresponding increase to additional paid-in capital.