RA CAPITAL MANAGEMENT, L.P. bought VOR

Footnotes

RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund"). 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, Dr. Kolchinsky and Mr. Shah disclaims beneficial ownership of any of the reported securities, except to the extent of its or his respective pecuniary interest therein.; This option was granted to Andrew Levin pursuant to the Issuer's non-employee director compensation policy. Under Dr. Levin's arrangement with the Adviser, Dr. Levin held the option for the benefit of the Fund. Dr. Levin is obligated to turn over to the Adviser any stock received upon exercise of the option, which will offset advisory fees owed by the Fund to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of the option and underlying common stock.