Few plants have generated as much recent interest among scientist and medical communities as the Madagascar periwinkle, Catharanthus roseus .
The interst began in the mid-1950's, when researchers, hearing of a "periwinkle tea" that was drunk in Jamaica, began to study the plant for its reported antidiabetic properties.
Extracts of entire dried plant contain many alkaloids of medicinal use. The principal alkaloid is vinblastine, or vincaleukoblastine (vinblastine sulfate), sold as Velban. The alkaloid has growth inhibition effects in certain human tumors. Vinblastine is used experimentally for treatment of neoplasms, and is recomanded for generalized Hodgkin's disease and resistant choricarcinoma.
Another pharmacologically important alkaloid is vincristine sulfate or vincristine, sold as Oncovin. Vincristine is used in treatment of leukemia in children.
Using vinblastine and vincristine in combination chemotherapy has resulted in 80% remission in Hodgkin's disease, 99% remission in acute lymphocitic leukemia, 80% remission in Wilm's tumor, 70% remission in gestational choricarcinoma, and 50% remission in Burkitt's lymphoma.
There are over 70 other alkaloid that have been isolated from the plant in addition to vinblastine and vincristine.
Synthetic vincristine, used to treat leukemia, is only 20% as effective as the natural product derived from Catharanthus roseus.
Further research is needed especially on bioactive compounds, means of preparation, and effectiveness of plants and herbal remedies.
(Duke,J.A.Handbook of Medicinal Herbs.1985;Magic and Medicine of Plants.1993).