Stockholders’ Equity

12 Months Ended

Dec. 31, 2022

Equity [Abstract]

Stockholders’ Equity

15.Stockholders’ Equity

Follow-on Offerings

On June 1, 2020, the Company entered into an underwriting agreement related to a public offering of 6,301,370 shares of its common stock, par value $0.0001 per share, including the exercise in full by the underwriters of their option to purchase an additional 821,917 shares, at the public offering price of $18.25 per share. The offering closed on June 5, 2020 and the Company received net proceeds of $107.7 million, after deducting the underwriting discount, commissions and offering expenses.

On December 1, 2020, the Company entered into an underwriting agreement related to a public offering of 5,513,699 shares of its common stock, par value $0.0001 per share, including the exercise in full by the underwriters of their option to purchase an additional 719,178 shares, at the public offering price of $36.50 per share. The offering closed on December 4, 2020 and the Company received net proceeds of $188.9 million, after deducting the underwriting discount, commissions and offering expenses.

On June 29, 2021, the Company entered into an underwriting agreement related to a public offering of 4,758,620 shares of its common stock, par value $0.0001 per share, including the exercise in full by the underwriters of their option to purchase an additional 620,689 shares at a public offering price of $145.00 per share. The offering closed on July 2, 2021 and the Company received net proceeds of $648.3 million, after deducting the underwriting discount, commissions and offering expenses.

In November 2022, the Company entered into an underwriting agreement related to a public offering of 6,550,219 shares of its common stock, par value $0.0001 per share, at a public offering price of $45.80 per share. In addition, the Company granted the underwriter an option exercisable for 30 days from the date of the agreement to purchase, at the public offering price less any underwriting discounts and commissions, up to an additional 982,532 shares. The offering closed on December 2, 2022 and the Company received net proceeds of $337.9 million, including the exercise in full of the underwriters' option to purchase additional shares, after deducting the underwriting discount, commissions and offering expenses.

At-the-Market Offering Programs

In August 2019, the Company entered into an Open Market Sale Agreement (the “2019 Sale Agreement”) with Jefferies LLC (“Jefferies”), under which Jefferies was able to offer and sell, from time to time in “at-the-market” offerings, common stock having aggregate gross proceeds of up to $150.0 million. The Company agreed to pay Jefferies cash commissions of 3.0% of the gross proceeds of sales of common stock under the 2019 Sale Agreement.

During the year ended December 31, 2020, the Company issued 2,270,161 shares of its common stock in a series of sales at an average price of $22.53 per share in accordance with the 2019 Sale Agreement, for aggregate net proceeds of $49.5 million after payment of cash commissions to Jefferies and approximately $0.2 million related to legal, accounting and other fees in connection with the sales. During the year ended December 31, 2021, the Company issued 641,709 shares of its common stock in a series of sales at an average price of $72.79 per share in accordance with the 2019 Sale Agreement, for aggregate net proceeds of $45.3 million after payment of cash commissions to Jefferies and approximately $0.1 million related to legal, accounting and other fees in connection with the sales. During the first quarter of 2022, the Company issued 579,788 shares of its common stock, in a series of sales, at an average price of $69.43 per share, in accordance with the 2019 Sale Agreement for aggregate net proceeds of $38.9 million, after payment of cash

commissions to Jefferies and approximately $0.2 million related to legal, accounting and other fees in connection with the sales. The 2019 Sale Agreement expired during the third quarter of 2022.

In March 2022, the Company entered into an Open Market Sale Agreement (the “2022 Sale Agreement”) with Jefferies, under which Jefferies will be able to offer and sell, from time to time in “at-the-market” offerings, common stock having aggregate gross proceeds of up to $400.0 million. The Company agreed to pay Jefferies cash commissions of 3.0% of the gross proceeds of sales of common stock under the 2022 Sale Agreement.

During the year ended December 31, 2022, the Company issued 3,395,339 shares of its common stock, in a series of sales, at an average price of $57.43 per share, in accordance with the 2022 Sale Agreement for aggregate net proceeds of $189.0 million, after payment of cash commissions to Jefferies and approximately $0.1 million related to legal, accounting and other fees in connection with the sales. As of December 31, 2022, $205.0 million in shares of common stock remain eligible for sale under the 2022 Sale Agreement.

Shares Issued in Private Placement to Regeneron

As described in Note 9 above, in May 2020 the Company entered into an amendment to its collaboration agreement with Regeneron that was entered into in April 2016. Simultaneously, the Company and Regeneron entered into the 2020 Stock Purchase Agreement, under which the Company sold to Regeneron 925,218 shares of its common stock, par value $0.0001 per share, for aggregate cash consideration of $30.0 million, or $32.42 per share, representing a 100% premium over the volume-weighted average trading price of the Company’s common stock during the 30-day period prior to the closing. Under the 2020 Stock Purchase Agreement, Regeneron will not dispose of any shares of common stock it beneficially owns in the Company until the termination of the Technology Collaboration Term (see Note 9). After applying equity accounting guidance to measure the issuance of the shares, $12.6 million was recorded as fair value in the consolidated statement of stockholders’ equity for the shares.