The aim of this first-in-human (FIH) open-label, multi-site study is to evaluate safety, tolerability, pharmacokinetics (PK), immunogenicity and preliminary clinical efficacy of BNT3212, including identification of the recommended dose of BNT3212 for use as monotherapy and with pumitamig (also known as BNT327 or PM8002) as combination therapy, in adults with advanced solid tumors who have exhausted other treatment options.