X0206 3 2020-07-16 0 0001810182 ALX ONCOLOGY HOLDINGS INC ALXO 0001750698 Vivo Capital IX, LLC C/O VIVO CAPITAL LLC 192 LYTTON AVENUE PALO ALTO CA 94301 0 0 1 0 0001750117 Vivo Capital Fund IX, L.P. C/O VIVO CAPITAL LLC 192 LYTTON AVENUE PALO ALTO CA 94301 0 0 1 0 Series C Convertible Preferred Stock Common Stock 3158851 I See footnote Each share of Series C Convertible Preferred Stock shall automatically convert into Common Stock on a 1:1 basis immediately prior to the completion of the Issuer's initial public offering of Common Stock and has no expiration date. The shares held of record by Vivo Capital Fund IX, L.P. (VIVO IX LP). Vivo Capital IX, LLC (VIVO IX LLC) is the General Partner of VIVO IX LP. As the managing members of Vivo Capital IX, LLC, the general partner of VIVO IX LP, Frank Kung, Albert Cha, Edgar Engleman, Shan Fu and Chen Yu share voting and dispositive power with respect to the shares held of record by VIVO IX LP but each disclaims beneficial ownership of such shares except to the extent of his individual pecuniary interest therein. /s/ Albert Cha, as a managing member of Vivo Capital IX, LLC 2020-07-16 /s/ Albert Cha, as a managing member of Vivo Capital IX, LLC, the general partner of Vivo Capital Fund IX, L.P. 2020-07-16