pegylated liposomal doxorubicin + atezolizumab + docetaxel + fluorouracil

This formulation is a combination therapy consisting of four agents: **pegylated liposomal doxorubicin**, **atezolizumab**, **docetaxel**, and **fluorouracil**. - **Pegylated liposomal doxorubicin** is a liposomal anthracycline chemotherapy that encapsulates doxorubicin in PEG-coated liposomes, enhancing tumor targeting and reducing systemic toxicity by prolonging circulation and exploiting tumor vessel permeability. Its primary mechanism is inhibition of topoisomerase 2, leading to DNA damage and cell death[3][5][7][11]. - **Atezolizumab** is a humanized monoclonal antibody that targets programmed death-ligand 1 (PD-L1) on tumor cells and tumor-infiltrating immune cells, blocking its interaction with PD-1 and B7.1 receptors and thereby restoring anti-tumor T-cell activity; it is classified as a checkpoint inhibitor immunotherapy. - **Docetaxel** is a taxane chemotherapy that promotes microtubule assembly and inhibits their disassembly, disrupting mitotic cell division and leading to apoptosis. - **Fluorouracil** (5-FU) is an antimetabolite chemotherapeutic that is metabolized intracellularly to active forms inhibiting thymidylate synthase, causing DNA synthesis inhibition and cell death[2][4][6][8][10]. This combination is used as an investigational regimen in oncology, mainly for solid tumors including refractory or metastatic cancers.