F1These securities are held directly by Clarus Lifesciences III, L.P. ("Clarus III"). Clarus Ventures III GP, L.P. ("Clarus III GP") is the sole general partner of Clarus III. Blackstone Clarus III L.L.C. is the sole general partner of Clarus GP. The sole member of Blackstone Clarus III L.L.C. is Blackstone Holdings II L.P. The sole general partner of Blackstone Holdings II L.P. is Blackstone Holdings I/II GP Inc. The controlling shareholder of Blackstone Holdings I/II GP Inc. is The Blackstone Group L.P. The sole general partner of The Blackstone Group L.P. is Blackstone Group Management L.L.C. Blackstone Group Management L.L.C. is wholly-owned by Blackstone's senior managing directors and controlled by its founder, Stephen A. Schwarzman.
F2Information with respect to each of the Reporting Persons is given solely by such Reporting Person, and no Reporting Person has responsibility for the accuracy or completeness of information supplied by another Reporting Person.
F3Each of such Reporting Persons may be deemed to beneficially own the shares beneficially owned by Clarus III, but each disclaims beneficial ownership of such shares, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons are the beneficial owners of any securities reported herein.

Remarks

This Form 3 is being filed in connection with the acquisition by The Blackstone Group L.P. and certain of its affiliates ("Blackstone") of Clarus Ventures, LLC and certain of its affiliates (collectively, "Clarus"). On January 4, 2019, Blackstone integrated the Clarus business into Blackstone (the "Clarus Integration"). As a result of such integration, Blackstone may be deemed to have become the beneficial owner of the securities beneficially owned by Clarus, including the securities of the Issuer.