rituximab + siplizumab + cyclophosphamide + tegoprubart

This combination consists of four agents: **rituximab**, **siplizumab**, **cyclophosphamide**, and **tegoprubart**. - **Rituximab** is a chimeric monoclonal antibody targeting CD20, a B-cell surface antigen, leading to B-cell depletion. It is primarily used in B-cell malignancies and some autoimmune diseases. - **Siplizumab** is a humanized monoclonal antibody that binds to CD2 on T cells and natural killer (NK) cells, interfering with T-cell activation and expansion, resulting in depletion of NK and T cells[4]. - **Cyclophosphamide** is a nitrogen mustard alkylating agent that crosslinks DNA, leading to cell death. It is used in a range of cancers (lymphomas, leukemia, myeloma, neuroblastoma, ovarian/breast carcinoma) and as an immunosuppressant[5][6][8]. - **Tegoprubart** is a monoclonal antibody under clinical investigation targeting CD40 ligand (CD154), designed to modulate immune responses (information inferred by expert consensus, as no direct clinical trial or regulatory data for this specific four-drug combination was found in the search results). This combination has not been identified as a marketed, regulated, or well-studied product as a four-drug fixed regimen. There is evidence for clinical use of rituximab, siplizumab, and cyclophosphamide in combination (often with other agents such as in the EPOCH-R regimen, which also includes etoposide, prednisone, vincristine, and doxorubicin for certain T- and NK-cell lymphomas)[1][4][10]. Tegoprubart has not been documented in established clinical or regulatory sources as being combined with these other three drugs.