X0306 4 2021-11-09 0001865494 IO Biotech, Inc. IOBT 0001750698 Vivo Capital IX, LLC C/O VIVO CAPITAL LLC 192 LYTTON AVENUE PALO ALTO CA 94301 true 0001750117 Vivo Capital Fund IX, L.P. C/O VIVO CAPITAL LLC 192 LYTTON AVENUE PALO ALTO CA 94301 true Common Stock 2021-11-09 4 C 0 2365545 A 2365545 D Common Stock 2021-11-09 4 P 0 650000 14 A 3015545 D Series C Preferred Stock 2021-11-09 4 C 0 188168 0 D Common Stock 2365545 0 D Upon the closing of the Issuer's initial public offering, each share of Series C Preferred Stock beneficially owned by the reporting person automatically converted, for no additional consideration, into the number of shares of Common Stock reported in Column 7 of Table II. These shares of Series C Preferred Stock had no expiration date. The shares are held directly by Vivo Capital Fund IX, L.P. Vivo Capital IX, LLC is the general partner of Vivo Capital Fund IX, L.P. As the managing members of Vivo Capital IX, LLC, Frank Kung, Edgar Engleman, Shan Fu, Hongbo Lu, Mahendra Shah, Jack Nielsen and Michael Chang share voting and dispositive power over the shares held by Vivo Capital Fund IX, L.P., but each disclaims beneficial ownership of such shares except to the extent of their individual pecuniary interest therein /s/ Jack Nielsen, as a Managing Member of Vivo Capital IX, LLC 2021-11-12 /s/ Jack Nielsen, as a Managing Member of Vivo Capital IX, LLC, the General Partner of Vivo Capital Fund IX, L.P. 2021-11-12