A Study to Learn About the Study Medicine Called PF-08046876 in People With Advanced Solid Tumors

Who May Qualify: - 18 years of age or older - Advanced cancer of the bladder, lung, head and neck, esophagus, or pancreas - Measurable disease - You should be able to carry out daily activities with 0 level of ability (ECOG 0)-1 - Part 1: progression or relapse following standard treatments - Part 2: maximum of 2 prior lines of systemic therapy in the advanced setting - Resolution of acute effects of prior anticancer therapy to baseline or Grade 1 - Consent to submit required pre-treatment tumor tissue as medically feasible Who Should NOT Join This Trial: - Received prior treatment with an antibody drug conjugate with a camptothecin-class payload (e.g. sacituzumab govitecan, trastuzumab deruxtecan ) - Active anorexia, nausea or vomiting, and/or signs of intestinal obstruction meeting protocol exclusion - Pulmonary disease meeting protocol exclusion - Other unacceptable abnormalities as defined by protocol Always talk to your doctor about whether this trial is right for you.