X0508 4 2023-08-23 1 0001814140 Apexigen, Inc. APGN 0001423786 Sarena Francis Willard C/O APEXIGEN, INC. 900 INDUSTRIAL ROAD, SUITE C SAN CARLOS CA 94070 0 1 0 0 President and COO 0 Common Stock 2023-08-23 4 F 0 31123 0.3851 D 124296 D Common Stock 2023-08-23 4 D 0 124296 D 0 D Employee Stock Option (right to buy) 4.79 2023-08-23 4 D 0 269847 D 2032-01-23 Common Stock 269847 0 D The shares were withheld to satisfy the reporting person's tax liability in connection with the vesting of restricted stock units. Pursuant to an Agreement and Plan of Merger, dated as of May 23, 2023 (the "Merger Agreement"), by and among the Issuer, Pyxis Oncology, Inc. ("Pyxis"), and Ascent Merger Sub Corp., at the effective time of the merger (the "Effective Time"), each share of Issuer common stock was exchanged for 0.1725 shares of Pyxis common stock and rounded down to the nearest whole share. One-fourth of the shares subject to the option vested on January 3, 2023 and 1/36th of the remaining shares vest monthly thereafter. Pursuant to the Merger Agreement, at the Effective Time, the option was assumed by Pyxis and converted into an option to purchase 46,547 shares of Pyxis common stock at an exercise price of $27.77 per share. /s/ Francis Sarena 2023-08-25