Transaction Details

Footnotes

On September 11, 2025, each of Polaris Partners VII, L.P. ("PP VII") and Polaris Entrepreneurs' Fund VII, L.P. ("PEF VII") acquired shares in a private placement by the Issuer pursuant to the terms of a Securities Purchase Agreement, dated as of September 9, 2025, by and among the Issuer and the investors party thereto at a purchase price of $1.53 per share. | The reported securities are owned directly by PP VII. Polaris Management Co. VII, L.L.C. ("PMC VII") is the general partner of PP VII. Each of David Barrett, Brian Chee, the Reporting Person, a member of the Issuer's board of directors, and Bryce Youngren (collectively, the "PMC VII Managing Members") are the managing members of PMC VII. Each of PMC VII and the PMC VII Managing Members, including the Reporting Person, in their respective capacities with respect to PMC VII, may be deemed to have shared voting, investment and dispositive power with respect to the securities held by PP VII. | Each of PMC VII and the PMC VII Managing Members, including the Reporting Person, disclaims beneficial ownership of these securities and this report shall not be deemed an admission that any one of the PMC VII Managing Members or PMC VII is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interests therein. | The reported securities are owned directly by PEF VII. PMC VII is the general partner of PEF VII. Each of PMC VII and the PMC VII Managing Members, including the Reporting Person, in their respective capacities with respect to PMC VII, may be deemed to have shared voting, investment and dispositive power with respect to the securities held by PEF VII. Each of PMC VII and the PMC VII Managing Members, including the Reporting Person, disclaims beneficial ownership of these securities and this report shall not be deemed an admission that any one of the PMC VII Managing Members, including the Reporting Person, or PMC VII is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interests therein. | The reported securities are owned directly by Polaris Partners X, L.P. ("PP X"). Polaris Partners GP X, L.L.C. ("PPGP X") is the general partner of PP X. Each of Amy Schulman and Brian Chee are the managing members of PPGP X (the "PPGP X Managing Members"). The Reporting Person, a member of the Issuer's board of directors, is an interest holder of PPGP X. Each of PPGP X, the PPGP X Managing Members and the Reporting Person, in their respective capacities with respect to PPGP X, may be deemed to have shared voting, investment and dispositive power with respect to the securities held by PP X. | Each of PPGP X, the PPGP X Managing Members and the Reporting Person disclaims beneficial ownership of these securities and this report shall not be deemed an admission that any one of the PPGP X Managing Members, the Reporting Person or PPGP X is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interests therein.