A Trial to Find Out if REGN4336 is Safe and How Well it Works Alone and in Combination With Cemiplimab or REGN5678 for Adult Participants With Advanced Prostate Cancer

Exclusion Criteria

• •1. Has received treatment with an approved systemic therapy within 3 weeks of dosing or has not yet recovered (ie, grade ≤1 or baseline) from any acute toxicities
• •2. Has received any previous systemic biologic or immune-modulating therapy (except for Sipuleucel-T) within 5 half-lives of first dose of study therapy, as described in the protocol
• •3. Has received prior PSMA-targeting therapy. Exception: Prior therapy with approved PSMA-targeted radioligand(s) is permitted
• •4. Any condition that requires ongoing/continuous corticosteroid therapy (\>10 mg prednisone/day or anti-inflammatory equivalent) within 1 week prior to the first dose of study therapy
• •5. Ongoing or recent (within 5 years) evidence of significant autoimmune disease that required treatment with systemic immunosuppressive treatments
• •6. Encephalitis, meningitis, neurodegenerative disease (with the exception of mild dementia that does not interfere with activities of daily living \[ADLs\]) or uncontrolled seizures in the year prior to first dose of study therapy
• •7. Uncontrolled infection with human immunodeficiency virus (HIV), hepatitis B or hepatitis C infection; or diagnosis of immunodeficiency, as described in the protocol.