ORBIMED ADVISORS LLC - 25 Jan 2022 Form 4 Insider Report for 89bio, Inc. (ETNB)

Footnote F1

Represents the weighted average sale price of the shares of the Issuer's common stock ("Shares") sold ranging from a low of $8.40 to a high of $8.58 per Share. The Reporting Person undertakes, upon request by the Commission staff, the Issuer or a security holder of the Issuer, to provide full information regarding the number of Shares purchased at each separate price.

Footnote F2

These Shares are held of record by OrbiMed Private Investments VI, LP ("OPI VI"). OrbiMed Capital GP VI LLC ("OrbiMed GP VI") is the general partner of OPI VI and OrbiMed Advisors LLC ("OrbiMed Advisors"), a registered investment adviser under the Investment Advisors Act of 1940, as amended, is the managing member of OrbiMed GP VI. By virtue of such relationships, OrbiMed GP VI and OrbiMed Advisors may be deemed to have voting and investment power with respect to the securities held by OPI VI noted above and, as a result, may be deemed to have beneficial ownership over such securities. OrbiMed Advisors exercises this investment and voting 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 OPI VI.

Footnote F3

The Shares were sold in block sale at a price of $8.38.

Footnote F4

These Shares are held of record by OrbiMed Israel Partners II, L.P. ("OIP II"). OrbiMed Israel GP II, L.P. ("Israel GP II") is the general partner of OIP II, and OrbiMed Advisors Israel II Limited ("Advisors Israel II") is the general partner of Israel GP II. By virtue of such relationships, Israel GP II and Advisors Israel II may be deemed to have voting and investment power with respect to the securities held directly by OIP II noted above and, as a result, may be deemed to have beneficial ownership over such securities. Advisors Israel II exercises this investment and voting power through a management committee comprised of Carl L. Gordon, David P. Bonita, and Erez Chimovits, each of whom disclaims beneficial ownership of the shares held by OIP II.

Footnote F5

This report is being jointly filed by OrbiMed Advisors, OrbiMed GP VI, Israel GP II, and Advisors Israel II. 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. This report shall not be deemed an admission that any of the Reporting Persons is a beneficial owner of such securities for the purpose of Section 16 of the Exchange Act, or for any other purpose.