12. Stockholders’ equity

Increase of Authorized Shares and Reverse Stock Split

Effective on September 15, 2022. the number of authorized shares of the Company’s common stock was increased from 200,000,000 shares (on a pre-split basis) to 700,000,000 shares (on a pre-split basis).

On September 16, 2022, the number of authorized shares of the Company’s common stock was proportionately adjusted from 700,000,000 to 70,000,000 as a result of the Reverse Stock Split. Immediately following the Reverse Stock Split, and without giving effect to the shares of the Company’s common stock issued in connection with the Merger and the 2022 Private Placement, there were approximately 6.3 million shares of the Company’s common stock outstanding. The Company’s common stock began trading on The Nasdaq Global Select Market on a split-adjusted basis on September 19, 2022.

No fractional shares were issued in connection with the Reverse Stock Split. Any fractional shares resulting from the Reverse Stock Split were rounded down to the nearest whole number, and each stockholder who would have otherwise been entitled to a fraction of a share of common stock upon the Reverse Stock Split (after aggregating all fractions of a share to which such stockholder would have otherwise been entitled) was, in lieu thereof, entitled to receive a cash payment.

Issuance of Securities through a Private Placement

On September 16, 2022, the Company issued in a private placement 6,387,173 shares of common stock, and, in lieu of shares of common stock, the 2022 Pre-Funded Warrants to purchase an aggregate of 7,426,739 shares of common stock, and, in each case, the accompanying 2022 Warrants to purchase an aggregate of up to 13,813,912 additional shares of common stock (or 2022 Pre-Funded Warrants to purchase common stock in lieu thereof) at a price of $10.34 per share and accompanying 2022 Warrant (or $10.33 per 2022 Pre-Funded Warrant and accompanying 2022 Warrant). The 2022 Private Placement resulted in aggregate gross proceeds of $129.9 million, before $10.1 million of transaction costs.

On December 8, 2020, through a private placement, the Company issued 1,031,250 shares of common stock, and, in lieu of shares of common stock, 2020 Pre-Funded Warrants to purchase an aggregate of 100,000 shares of common stock, and, in each case, accompanying 2020 Warrants to purchase an aggregate of up to 282,809 additional shares of common stock (or 2020 Pre-Funded Warrants to purchase common stock in lieu thereof) at a price of $80.00 per share and accompanying 2020 Warrant (or $79.90 per 2020 Pre-Funded Warrant and accompanying 2020 Warrant). The private placement resulted in aggregate gross proceeds of $90.5 million, before $0.4 million of transaction costs.

In the event of certain fundamental transactions involving the Company, the holders of 2022 Warrants and 2020 Warrants may require the Company to make a payment based on a Black-Scholes valuation, using specified inputs. The holders of 2022 Pre-Funded Warrants and 2020 Pre-Funded Warrants do not have similar rights. Therefore, the Company accounted for the 2022 Warrants and 2020 Warrants as liabilities, while the 2022 Pre-Funded Warrants and 2020 Pre-Funded Warrants met the permanent equity criteria classification. The 2022 Pre-Funded Warrants and 2020 Pre-Funded Warrants are classified as a component of permanent equity because they are freestanding financial instruments that are legally detachable and separately exercisable from the shares of common stock with which they were issued, are immediately exercisable, do not embody an obligation for the Company to repurchase its shares, and permit the holders to receive a fixed number of shares of common stock upon exercise. In addition, the 2022 Pre-Funded Warrants and 2020 Pre-Funded Warrants do not provide any guarantee of value or return. The initial fair value of the 2022 Warrants and 2020 Warrants was $64.7 million and $19.3 million, respectively, determined using the Black-Scholes valuation model. The Company remeasured the aggregate fair value of the 2022 Warrants and 2020 Warrants at December 31, 2022 and 2021 as $24.5 million and $3.0 million, respectively. The change in fair value of $43.2 million

(gain), $16.7 million (gain) and $0.4 million (loss) was recorded in the Company’s statement of operations for the years ended December 31, 2022, 2021, and 2020 respectively.

Issuance of Securities through an Underwritten Public Offering

On January 22, 2021, the Company issued and sold an aggregate of 540,000 shares of its common stock in an underwritten public offering at a public offering price of $140.00 per share, resulting in gross proceeds of $75.6 million before deducting underwriting discounts and commissions and other transaction expenses of approximately $5.1 million.

Convertible Preferred Stock and 2019 Warrants

On April 9, 2019, the Company completed two concurrent underwritten public offerings of its equity securities. In the first public offering, the Company sold 866,733 shares of its common stock and accompanying 2019 Warrants to purchase 195,184 shares of the Company’s common stock, at a combined price to the public of $75.0 per common share and accompanying 2019 Warrant. In the second public offering, the Company sold 666 shares of its Series A Preferred Stock, and accompanying 2019 Warrants to purchase 16,650 shares of the Company’s common stock, at a combined public offering price of $75,000 per share and accompanying 2019 Warrant. The offerings resulted in aggregate gross proceeds to the Company of $70.0 million, before underwriting discounts and commissions and offering expenses payable by the Company of approximately $5.0 million.

In November 2019, all 666 shares of Series A Preferred Stock were converted to 66,600 shares of common stock. As of December 31, 2022, there were no shares of Series A Preferred Stock outstanding.

Each 2019 Warrant had an exercise price per share of common stock of $86.25, subject to adjustment in certain circumstances. Each 2019 Warrant was immediately exercisable upon issuance, provided that the holder was prohibited, subject to certain exceptions, from exercising the 2019 Warrant for shares of the Company’s common stock to the extent that immediately prior to or after giving effect to such exercise, the holder, together with its affiliates and other attribution parties, would own more than 4.99% of the total number of shares of the Company’s common stock then issued and outstanding. This percentage could be changed at the holders’ election to a higher or lower percentage upon 61 days’ notice to the Company.

As of December 31, 2022, there are no outstanding 2019 Warrants as the remaining unexercised 2019 Warrants to purchase 211,709 shares of common stock expired on October 10, 2022.