cyclophosphamide + doxorubicin + epirubicin + paclitaxel + pembrolizumab

This is a multi-agent combination regimen consisting of five distinct anticancer drugs: - **Cyclophosphamide** is an alkylating agent that interferes with DNA replication and transcription, leading to cell death. - **Doxorubicin** and **epirubicin** are anthracycline antibiotics that intercalate into DNA, inhibit topoisomerase II, and generate free radicals, resulting in cytotoxicity. - **Paclitaxel** is a taxane that stabilizes microtubules and inhibits their disassembly, disrupting mitosis. - **Pembrolizumab** is a monoclonal antibody targeting the programmed cell death protein 1 (PD-1) receptor on T cells. By blocking PD-1 interaction with its ligands (PD-L1/PD-L2), pembrolizumab enhances immune-mediated tumor cell killing[5][6][8]. This combination brings together traditional cytotoxic chemotherapy agents (cyclophosphamide, doxorubicin, epirubicin, paclitaxel) with immunotherapy (pembrolizumab). Such regimens are under investigation or used in clinical practice for various solid tumors—most notably breast cancer—where combining chemotherapy with immune checkpoint inhibition may improve outcomes.