indication

For treatment of breast cancer, testicular cancer, lymphomas, neuroblastoma, Hodgkin's and non-Hodgkin's lymphomas, mycosis fungoides, histiocytosis, and Kaposi's sarcoma.

pharmacology

Vinblastine is a vinca alkaloid antineoplastic agent. The vinca alkaloids are structurally similar compounds comprised of 2 multiringed units: vindoline and catharanthine. The vinca alkaloids have become clinically useful since the discovery of their antitumour properties in 1959. Initially, extracts of the periwinkle plant (Catharanthus roseus) were investigated because of putative hypoglycemic properties, but were noted to cause marrow suppression in rats and antileukemic effects in vitro. Vinblastine has some immunosuppressant effect. The vinca alkaloids are considered to be cell cycle phase-specific.

mechanism of action

The antitumor activity of vinblastine is thought to be due primarily to inhibition of mitosis at metaphase through its interaction with tubulin. Vinblastine binds to the microtubular proteins of the mitotic spindle, leading to crystallization of the microtubule and mitotic arrest or cell death.

toxicity

Oral, mouse: LD₅₀ = 423 mg/kg; Oral, rat: LD₅₀ = 305 mg/kg.

biotransformation

Hepatic. Metabolism of vinblastine has been shown to be mediated by hepatic cytochrome P450 3A isoenzymes.

half life

Triphasic: 35 min, 53 min, and 19 hours

route of elimination

The major route of excretion may be through the biliary system.

drug interactions

Amprenavir: Amprenavir, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Amprenavir is initiated, discontinued or dose changed.

Aprepitant: Aprepitant may change levels of the chemotherapy agent, vinblastine.

Atazanavir: Atazanavir, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Atazanavir is initiated, discontinued or dose changed.

Clarithromycin: Clarithromycin, a CYP3A4 and p-glycoprotein inhibitor, may increase the Vinblastine serum concentration and distribution in certain cells. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Clarithromycin is initiated, discontinued or dose changed.

Conivaptan: Conivaptan, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Conivaptan is initiated, discontinued or dose changed.

Dabigatran etexilate: P-Glycoprotein inducers such as vinblastine may decrease the serum concentration of dabigatran etexilate. This combination should be avoided.

Darunavir: Darunavir, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Darunavir is initiated, discontinued or dose changed.

Delavirdine: Delavirdine, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Delavirdine is initiated, discontinued or dose changed.

Dirithromycin: Dirithromycin, a CYP3A4 and p-glycoprotein inhibitor, may increase the Vinblastine serum concentration and distribution in certain cells. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Dirithromycin is initiated, discontinued or dose changed.

Erythromycin: Erythromycin, a CYP3A4 and p-glycoprotein inhibitor, may increase the vinblastine serum concentration and distribution in certain cells. Consider alternate therapy to avoid vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of vinblastine if erythromycin is initiated, discontinued or dose changed.

Fluconazole: Increases the effect and toxicity of anticancer agent

Fosamprenavir: Fosamprenavir, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Fosamprenavir is initiated, discontinued or dose changed.

Fosphenytoin: The antineoplasic agent decreases the effect of hydantoin

Imatinib: Imatinib, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Imatinib is initiated, discontinued or dose changed.

Indinavir: Indinavir, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Indinavir is initiated, discontinued or dose changed.

Isoniazid: Isoniazid, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Isoniazid is initiated, discontinued or dose changed.

Itraconazole: Itraconazole, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Itraconazole is initiated, discontinued or dose changed.

Ketoconazole: Ketoconazole, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Ketoconazole is initiated, discontinued or dose changed.

Leflunomide: Vinblastine may increase the adverse/toxic effects of Leflunomide. This may increase the risk of hematologic toxicities such as pancytopenia, agranulocytosis and thrombocytopenia. In patients receiving Vinblastine, consider eliminating the loading dose of Leflunomide. Monitor for bone marrow suppression at least monthly during concomitant therapy.

Lopinavir: Lopinavir, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Lopinavir is initiated, discontinued or dose changed.

Miconazole: Miconazole, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Miconazole is initiated, discontinued or dose changed.

Mitomycin: Potentially severe lung toxicity

Natalizumab: Concomitant Vinblastine and Natalizumab therapy may increase the risk of infection. Concurrent therapy should be avoided.

Nefazodone: Nefazodone, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Nefazodone is initiated, discontinued or dose changed.

Nelfinavir: Nelfinavir, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Nelfinavir is initiated, discontinued or dose changed.

Nicardipine: Nicardipine, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Nicardipine is initiated, discontinued or dose changed.

Phenytoin: The antineoplasic agent decreases the effect of hydantoin

Posaconazole: Posaconazole, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Posaconazole is initiated, discontinued or dose changed.

Quinidine: Quinidine, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Quinidine is initiated, discontinued or dose changed.

Quinupristin: This combination presents an increased risk of toxicity

Ritonavir: Ritonavir, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Ritonavir is initiated, discontinued or dose changed.

Saquinavir: Saquinavir, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Saquinavir is initiated, discontinued or dose changed.

Telithromycin: Telithromycin, a CYP3A4 and p-glycoprotein inhibitor, may increase the Vinblastine serum concentration and distribution in certain cells. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic and adverse effects of Vinblastine if Telithromycin is initiated, discontinued or dose changed.

Tolterodine: Vinblastine, a CYP3A4 inhibitor, may increase the serum concentration of Tolterodine by decreasing its metabolism. Poor CYP2D6 metabolizers metabolize Tolterodine via CYP3A4. A dose adjustment of Tolterodine may be required. Monitor for changes in the therapeutic/adverse effects of Tolterodine if Vinblastine is initiated, discontinued or dose changed.

Trastuzumab: Trastuzumab may increase the risk of neutropenia and anemia. Monitor closely for signs and symptoms of adverse events.

Voriconazole: Voriconazole, a strong CYP3A4 inhibitor, may decrease the metabolism of Vinblastine. Consider alternate therapy to avoid Vinblastine toxicity. Monitor for changes in the therapeutic/adverse effects of Vinblastine if Voriconazole is initiated, discontinued or dose changed.