In connection with the acquisition of CorHepta in February 2025 (see Note 10), the Company issued a combined 1,660,222 shares of restricted common stock to two selling shareholders who were subsequently employed by the Company, which are subject to a combination of post-acquisition service- and performance-based vesting conditions, as follows: (i) 996,133 shares vested on the first anniversary of the closing of the acquisition, (ii) the remaining 664,089 shares were forfeited on February 21, 2026 as a result of the non-achievement of a certain milestone specified in the Merger Agreement.

For the restricted shares with service-based vesting conditions, stock-based compensation expense is recognized on a straight-line basis over the service period, which is generally the vesting term. For restricted shares with performance-based vesting conditions, stock-based compensation expense is recognized over the requisite service period when it is probable that the performance condition will be achieved.

The weighted-average grant date fair value of the restricted shares issued in connection with the asset acquisition was $4.9 million. During the three months ended March 31, 2026 and March 31, 2025, the Company recognized stock-based compensation expense of $0.4 million and $0.3 million, respectively, related to the restricted shares with service-based vesting conditions. No stock-based compensation expense was recognized related to the restricted shares with performance-based vesting conditions during the three months ended March 31, 2026, as the performance conditions were not achieved. As of March 31, 2026, there was $0 of unrecognized compensation expense related to the restricted shares issued in connection with the acquisition of CorHepta.

Stock Options

During the three months ended March 31, 2026, the Company granted 11,627,899 options with a weighted average strike price of $1.99 to purchase common stock to certain employees that either (i) vest on the first anniversary of the grant of such option in the amount of one-fourth of such grant, and the remaining portion will vest in 36 equal monthly installments thereafter, or (ii) vest in 36 equal monthly installments. The total aggregate grant date fair value of all options granted was $18.5 million.

During the three months ended March 31, 2025, the Company granted 21,329,195 options with a weighted average strike price of $2.52 to purchase common stock to certain employees that either (i) vest annually in three equal parts over three years, (ii) vest on the first anniversary of the grant of such option in the amount of one-third of such grant, and the remaining portion will vest in 36 equal monthly installments thereafter, (iii) vest in 48 equal monthly installments, (iv) vest annually over two years, or (v) vest annually over four years. The Company also granted 2,056,049 performance-based options with a weighted average strike price of $2.35 to purchase common stock to certain employees. These options are subject to performance vesting and will vest and become exercisable once the performance conditions are probable of being met. There is no assurance that the performance conditions will be met and therefore some or all of these options may never vest or become exercisable. The total aggregate grant date fair value of all options granted was $43,113,397. During the three months ended March 31, 2025, certain performance conditions were probable of being met.

For awards with performance conditions in which the award does not vest unless the performance condition is met, the Company recognizes expense if, and to the extent that, the Company estimates that achievement of the performance condition is probable. If the Company concludes that vesting is probable, the Company recognizes expense from the date the Company reaches this conclusion through the estimated vesting date.

Stock-Based Compensation Expense