X0306 4 2021-02-05 0 0001785173 89bio, Inc. ETNB 0001792064 Waisbourd Ram C/O 89BIO, INC. 142 SANSOME STREET, 2ND FLOOR SAN FRANCISCO CA 94104 0 1 0 0 See Remarks Common Stock 2021-02-05 4 A 0 4000 0.00 A 4000 D Stock Option (Right to Buy) 23.01 2021-02-05 4 A 0 32500 0.00 A 2031-02-05 Common Stock 32500 32500 D Performance stock units vest with respect to 4,000 shares in three equal installments on the first, second and third anniversaries of February 5, 2021, subject to the achievement of specified milestone events and the Reporting Person's continued service to the Issuer. This option represents a right to purchase a total of 32,500 shares of the Issuer's Common Stock, one quarter of which will vest on February 5, 2022, with the remaining three quarters vesting in equal quarterly installments over the following three years, subject to the Reporting Person's continued service to the Issuer. Chief Operating Officer and Chief Business Officer /s/ Ryan A. Murr, as attorney-in-fact for Ram Waisbourd 2021-02-09