Dr. Howard Scher discusses MDV3100, a novel oral androgen receptor antagonist.

 A few years ago Dr. Charles Sawyers M.D. made discoveries about the androgen receptor that led to this new drug MDV3100. Dr. Sawyers' lab synthesized a series of organic small molecules until he found onethat binds to the androgen receptor after androgen-receptor blockers like Casodex had failed.

"Because MDV3100 binds to the androgen receptor and blocks subsequent DNA binding, it can inhibit the growth of prostate cancer cells that have failed standard hormonal therapies and even chemotherapies," Sawyers says.

So far, MDV3100 has been tested in a Phase 1/2 trial, which is no longer taking in new patients but has yet to fully wrap up. Dr. Scher mentions in the video that a Phase 3 trial is planned for this fall. On March 19, Medivation announced that it had received FDA permission to begin this pivotal Phase 3 trial. It will test the drug on patients who have ceased to respond both to androgen suppression and to Taxotere. The randomized, placebo-controlled, double-blind, multinational trial will enroll some 1,200 patients, with overall survival as the primary endpoint.

Some of the company's "forward-looking" statements on the drug's future are set out in this press release from Oct 22, 2008: MDV3100 Continues to Show Encouraging and Durable Anti-Tumor Activity and Dose Escalation Continues. Dr. Scher says there: "The tolerability and the anti-tumor activity seen with MDV3100 after six months of treatment remains encouraging." In this video Dr. Scher gives more details about patient responses and mentions that two patients experienced seizure as a side effect.

This month, April 7, the company published an article in the online version of the journal Science, outlining the steps in the drug's discovery and describing how it works. Technically, MDV3100 is described as an androgen receptor antagonist that inhibits androgen receptor function by blocking nuclear translocation of the androgen receptor and DNA binding. "I believe that MDV3100 is an important potential new approach to treating this disease and am encouraged that the drug is moving into Phase 3 clinical development," Dr. Sawyers says.

by J. Strax.

Howard I. Scher, M.D., is Chief, Genitourinary Oncology Service; D. Wayne Calloway Chair in Urologic Oncology