Vinblastine

Vinblastine is a chemotherapy drug in the vinca alkaloid class. It is derived from the plant Catharanthus roseus (Madagascar periwinkle) and is used to treat various cancers, usually as part of combination regimens. It is closely related to vincristine and vinorelbine.

Mechanism of action: Vinblastine binds to tubulin and inhibits microtubule polymerization, preventing the formation of the mitotic spindle. This disrupts mitosis and causes cell cycle arrest in metaphase, leading to apoptotic cell death in rapidly dividing tumor cells.

Clinical use: Vinblastine is a component of several regimens for Hodgkin lymphoma, notably ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine). It is also used in regimens for germ cell tumors (for example PVB), certain soft tissue cancers, and some other solid tumors. It is administered intravenously and should be given through a suitable vein; it is a vesicant and can cause tissue injury if extravasated.

Adverse effects and precautions: The most significant toxicity is bone marrow suppression, with neutropenia, anemia, and thrombocytopenia. Other common effects include fatigue, stomatitis, nausea, mucositis, alopecia, and fever. Neurotoxicity is less prominent than with vincristine. Renal and hepatic function influence dosing, and regular monitoring of blood counts is required. Vinblastine is not given intrathecally due to risk of severe toxicity.