Phenoxodiol: pharmacology and clinical experience in cancer monotherapy and in combination with chemotherapeutic drugs

Background: Phenoxodiol is a synthetic derivative of the naturally occurring plant isoflavone genistein. The observation that an inverse relationship exists between dietary intake of isoflavones and cancer incidence has led to the evaluation of these compounds in cancer therapy. Objective: This article reviews the mechanisms of action of phenoxodiol and the completed and ongoing clinical studies evaluating this drug. Results/conclusions: By altering the chemical structure of genistein, the new compound phenoxodiol showed increased anticancer activity without any increase in toxicity. In addition to its direct cytotoxic activity against different cancers, phenoxodiol sensitizes chemoresistant ovarian cancer cells to platinum and taxane drugs, as well as gemcitabine and topotecan. The US Food and Drug Administration has granted ‘fast track’ status to the development of phenoxodiol as chemosensitizer for platinum and taxane drugs used in the treatment of recurrent ovarian cancer.