REGN4336 + cemiplimab

REGN4336 + cemiplimab is an investigational combination therapy for cancer, specifically being studied in metastatic castration-resistant prostate cancer (mCRPC). REGN4336 is a **bispecific antibody that targets both prostate-specific membrane antigen (PSMA) on tumor cells and CD3 on T cells**, redirecting T cell cytotoxic activity against PSMA-expressing prostate cancer cells. Cemiplimab is a **monoclonal antibody immune checkpoint inhibitor targeting PD-1 (programmed cell death protein 1)**, designed to potentiate immune-mediated antitumor responses by blocking inhibitory signaling in T cells. The combination aims to enhance T cell activation and function within the immunosuppressive microenvironment of mCRPC through dual mechanisms: targeted T cell engagement and checkpoint inhibition. The combination is being evaluated in open-label Phase 1/2 clinical trials for safety, tolerability, pharmacokinetics, and preliminary efficacy in advanced prostate cancer[1][2][3][5][6][7].