An Open-Label Study to Evaluate PF-07994525 in Participants With Advanced Cancers

Inclusion Criteria: * Participants aged 18 years or older (or the minimum age of consent in accordance with local regulations) at the time of informed consent. * Prior diagnosis of MM as defined according to IMWG criteria (Rajkumar et al. 2014) Measurable disease based on IMWG criteria as defined by at least 1 of the following: 1. Serum M-protein \>0.5 g/dL by serum protein electrophoresis (SPEP) 2. Urinary M-protein excretion \>200 mg/24 hours by urine protein electrophoresis (UPEP) 3. Serum immunoglobulin Free Light Chain (FLC) ≥10 mg/dL (≥100 mg/L) AND abnormal serum immunoglobulin kappa to lambda FLC ratio (\<0.26 or \>1.65) * Participants must be refractory to, or intolerant to, all established therapies known to provide clinical benefit in multiple myeloma that are an appropriate therapeutic option, in the judgement of the investigator. A minimum of 3 prior lines of therapy are required. * Eastern Cooperative Oncology Group (ECOG) performance status 0-1. Exclusion Criteria: * Active plasma cell leukemia, Smoldering MM, Waldenströms macroglobulinemia, Amyloidosis, POEMS Syndrome. * Autologous stem cell transplant within 12 weeks prior to enrollment or active Graft-versus-host disease (GVHD). * Active or suspected cerebral/meningeal disease related to the underlying malignancy. * Any active, uncontrolled bacterial, fungal, or viral infection, including (but not limited to) COVID-19, Hepatitis B Virus (HBV), Hepatitis C Virus (HCV), known HIV or AIDS related illness, unless deemed not clinically significant by the investigator (eg, onychomycosis).