RA CAPITAL MANAGEMENT, L.P. bought SGP

Footnotes

This option was granted to Dr. Zachary Scheiner pursuant to the Issuer's non-employee director compensation policy. Subject to Dr. Scheiner's continuing as an Outside Director (as defined in the Issuer's 2026 Equity Incentive Plan) through such applicable vesting date, one thirty-sixth (1/36th) of the shares subject to the option shall vest each month following the Date of Grant on the same day of the month as the Date of Grant (and if there is no corresponding day, on the last day of the month). "Date of Grant" shall mean February 5, 2026.; RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund III, L.P. (the "Nexus Fund III"). The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. Each of the Adviser, the Adviser GP, the Fund, the Nexus Fund III, Dr. Kolchinsky, and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of its or his respective pecuniary interest therein.; Under Dr. Scheiner,'s arrangement with the Adviser, Dr. Scheiner holds the option for the benefit of the Fund and the Nexus Fund III. Dr. Scheiner is obligated to turn over to the Adviser any net cash or stock received upon exercise of the option, which will offset advisory fees owed by the Fund and the Nexus Fund III to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of the option and underlying common stock.