ORBIMED ADVISORS LLC bought AVBP

Footnotes

Reflects shares purchased in the Issuer's initial public offering.; These securities are held of record by OrbiMed Asia Partners IV, L.P. ("OAP IV"). OrbiMed Asia GP IV, L.P. ("Asia GP IV") is the general partner of OAP IV and OrbiMed Advisors IV Limited ("Advisors IV") is the general partner of Asia GP IV. OrbiMed Advisors LLC ("OrbiMed Advisors") is the advisory company of OAP IV. By virtue of such relationships, Asia GP IV, Advisors IV, and OrbiMed Advisors may be deemed to have voting power and investment power over the securities held by OAP IV and as a result, may be deemed to have beneficial ownership over such securities. OrbiMed Advisors exercises voting and investment power through a management committee comprised of Carl L. Gordon, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the shares held by OAP IV.; This report on Form 4 is jointly filed by OrbiMed Advisors, GP VIII, Advisors IV, and Asia GP IV. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of its pecuniary interest therein, if any. The Reporting Persons have designated a representative, Carl L. Gordon, a member of OrbiMed Advisors, to serve on the Issuer's board of directors. This report shall not be deemed an admission that any such entity or person is a beneficial owner of such securities for purpose of Section 16 of the Exchange Act, or for any other purpose.