cyclophosphamide + doxorubicin + vincristine + lamivudine

This is a combination regimen consisting of four drugs: cyclophosphamide, doxorubicin, vincristine, and lamivudine. Cyclophosphamide is an alkylating agent that interferes with DNA replication and RNA transcription by forming cross-links in DNA. Doxorubicin is an anthracycline antibiotic that intercalates into DNA and inhibits topoisomerase II, leading to inhibition of DNA replication and generation of free radicals causing cytotoxicity. Vincristine is a vinca alkaloid that binds to tubulin, inhibiting microtubule formation required for cell division (mitosis). Lamivudine is a nucleoside reverse transcriptase inhibitor (NRTI) primarily used as an antiviral agent against HIV and hepatitis B virus; it inhibits viral reverse transcriptase by acting as a chain terminator during viral DNA synthesis. While the combination of cyclophosphamide, doxorubicin, and vincristine forms the backbone of several established chemotherapy regimens for hematologic malignancies such as non-Hodgkin lymphoma (e.g., CHOP or CAV regimens)[1][2][4], the inclusion of lamivudine in this combination is highly unusual. Lamivudine does not have established use in oncology or standard chemotherapeutic protocols involving these agents; its primary indication remains antiviral therapy.