X0508 4 2023-08-23 1 0001814140 Apexigen, Inc. APGN 0001230721 CROSS HERB C/O APEXIGEN, INC. 900 INDUSTRIAL ROAD, SUITE C SAN CARLOS CA 94070 1 0 0 0 0 Stock Option (right to buy) 6.94 2023-08-23 4 D 0 34084 D 2029-11-08 Common Stock 34084 0 D Stock Option (right to buy) 2.65 2023-08-23 4 D 0 100000 D 2032-09-29 Common Stock 100000 0 D The shares subject to the option vest in 48 equal monthly installments beginning on November 3, 2019. 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"), the option was assumed by Pyxis and converted into an option to purchase 5,879 shares of Pyxis common stock at an exercise price of $40.24 per share. In accordance with the reporting person's equity award agreement, vesting of the unvested shares underlying the option accelerated in full at the Effective Time. The shares subject to the option vest in three equal annual installments beginning on July 29, 2023. Pursuant to the Merger Agreement, at the Effective Time, the option was assumed by Pyxis and converted into an option to purchase 17,250 shares of Pyxis common stock at an exercise price of $15.37 per share. In accordance with the reporting person's equity award agreement, vesting of the unvested shares underlying the option accelerated in full at the Effective Time. /s/ Francis Sarena, by power of attorney 2023-08-25