obrixtamig + carboplatin + etoposide + durvalumab

This is a **four-drug combination regimen** composed of **obrixtamig (BI 764532/HPN328)**, **carboplatin**, **etoposide**, and **durvalumab**, evaluated primarily as a treatment for **advanced or metastatic small cell lung cancer (SCLC)** and related neuroendocrine carcinomas. - **Obrixtamig** is a novel *bispecific T-cell engager* that simultaneously targets delta-like ligand 3 (DLL3) expressed on tumor cells and CD3 on T cells, bridging the immune system to selectively kill DLL3-positive tumor cells. - **Carboplatin** is a platinum-based DNA crosslinking small molecule chemotherapy causing tumor cell apoptosis through DNA damage. - **Etoposide** is a topoisomerase II inhibitor, a small molecule chemotherapeutic that induces double-strand DNA breaks in tumor cells. - **Durvalumab** is a monoclonal antibody immune checkpoint inhibitor targeting programmed death-ligand 1 (PD-L1), blocking its interaction with PD-1 and thus enhancing anti-tumor immunity. The combination is being studied to assess potential additive or synergistic efficacy by targeting SCLC with immunotherapy, T-cell engagement, and cytotoxic chemotherapy. Obrixtamig is under development by Boehringer Ingelheim, and the other agents are established generics. This combination is experimental and not approved for routine clinical use as of mid-2025[2][1].