8. Stock-Based Compensation

2023 Inducement Plan

As of June 30, 2025, the Company had 69,668,889 shares of its common stock available for future issuance under the 2023 Inducement Plan.

Amended and Restated 2021 Equity Incentive Plan

As of June 30, 2025, the Company had 6,027,849 shares of its common stock available for future issuance under its Amended and Restated 2021 Equity Incentive Plan.

Stock Options

The Company’s stock options generally vest ratably over a four-year period and have a contractual term of ten years. The weighted-average assumptions used principally in determining the fair value of new options granted during the periods presented were as follows:

During the six months ended June 30, 2025 and 2024, the Company granted new stock options to purchase 87,549,888 shares and 1,722,725 shares of its common stock, respectively, with a weighted-average grant-date fair value of $0.73 and $1.74 per share, respectively. As of June 30, 2025, total unrecognized compensation expense related to stock options was $66.3 million, which is

expected to be recognized over a weighted-average period of 2.1 years. The intrinsic value of stock options exercised during the six months ended June 30, 2025 was immaterial.

As of June 30, 2025, there were no shares that were both exercised and unvested.

Option Repricing

On February 3, 2025, the Company's board of directors approved a stock option repricing (the “Option Repricing”) whereby the exercise price of certain outstanding options to purchase shares of the Company’s common stock was reduced to $1.34 per share. The repricing applied to options to purchase shares of the Company’s common stock held by continuing employees as of February 3, 2025 that had an exercise price per share greater than $1.34; provided that holders of repriced options must remain in continuous service with the Company through February 3, 2026 or, if earlier, a change in control of the Company or 30 days prior to the applicable repriced option’s original expiration date (the “Retention Period”). If any such repriced option is exercised prior to the end of the Retention Period, the exercise price per share will be the original exercise price per share, and not the repriced exercise price. The total number of shares underlying all repriced options was approximately 6.76 million shares. The repriced options previously had exercise prices ranging from $1.36 to $44.96 per share.

Management determined that the Option Repricing represents a modification of share-based awards and calculated incremental compensation cost of approximately $1.9 million resulting from the modification. However, as the conditions of the modified terms are not expected to be met as of June 30, 2025, the Company reversed any previously recognized incremental compensation cost associated with the modification during the quarter ended June 30, 2025.

Restricted Stock Units

During the six months ended June 30, 2025 and 2024, the Company granted 1,224,000 restricted stock units and 1,119,149 restricted stock units, respectively, with a weighted-average grant date fair value of $1.33 and $2.38 per share, respectively. As of June 30, 2025, total unrecognized compensation expense related to restricted stock units was $2.9 million, which is expected to be recognized over a weighted-average period of 2.3 years.

Employee Stock Purchase Plan

As of June 30, 2025, the Company had 2,318,649 shares of its common stock available for issuance under its Employee Stock Purchase Plan (“ESPP”). During the six months ended June 30, 2025, the Company issued 669,888 shares with a weighted-average purchase price of $0.15 under the ESPP, which resulted in an immaterial amount of compensation expense. During the six months ended June 30, 2024, the Company issued 74,326 shares with a weighted-average purchase price of $1.48 under the ESPP, which resulted in an immaterial amount of compensation expense.

Equity Award Modification

In connection with the Restructuring Plan, the Company executed an equity award modification which accelerated the vesting of the former Chief Executive Officer’s restricted stock units and options as a part of his consulting and separation agreement. The modification additionally extended the period for which vested options can be exercised following the employee’s final day of employment. During the six months ended June 30, 2025, the Company recognized $0.5 million of stock-based compensation expense related to the equity award modification as general and administrative expense within the condensed consolidated statement of operations and comprehensive loss.

Stock-Based Compensation