Podophyllotoxin derivatives: drug discovery and development

The exploration and exploitation of podophyllin formulations provide an example of how a plant extract with established ethnomedical use, but also causing toxicity, can provide a basis for new drug discovery and development. Applications and potential applications include the treatment of venereal warts, psoriasis, rheumatoid arthritis, malaria and Alzheimer's disease. This review addresses the history and pharmacological action of these natural products and outlines the preclinical development and clinical trials of drugs in the pipeline and with marketing approval.