Transaction Details

Footnotes

Represents the number of shares of the issuer's common stock underlying performance-based restricted stock units ("PSUs") granted in February 2023 that have been earned based on the level of achievement of the clinical milestone for complete enrollment in the Company's Phase 3 SENTRY trial, as certified by the issuer's Compensation Committee on September 12, 2025. Each earned PSU represents the contingent right to receive one share of the issuer's common stock upon vesting. The earned PSUs vested on September 12, 2025. | Includes 922 shares acquired by the reporting person under the Karyopharm Therapeutics Inc. Amended & Restated 2013 Employee Stock Purchase Plan on April 30, 2025. | This transaction was effected pursuant to a durable automatic sale instruction plan adopted by the reporting person on May 27, 2021, and represents a broker-assisted sale of shares to satisfy the payment of withholding tax liability incurred upon the vesting of PSUs. The sale does not represent a discretionary trade by the reporting person.