Transaction Details

Footnotes

This purchase was made for the purpose of extending the period during which acquisitions can be made pursuant to RA Capital Healthcare Fund, L.P.'s filing under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (as amended). | The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $6.685 to $6.695 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote. | 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. | Held directly by the Fund. | Represents previously reported restricted stock unit awards grant to Dr. Kolchinsky. | Dr. Kolchinsky is a Managing Partner of the Adviser who serves on the Issuer's board of directors. Under Dr. Kolchinsky's arrangement with the Adviser, Dr. Kolchinsky holds the RSUs for the benefit of the Fund. Dr. Kolchinsky is obligated to turn over to the Adviser any net cash or shares received upon settlement of the RSUs, which will offset advisory fees owed by the Fund to the Adviser.