SAN FRANCISCO (September 28, 2006) – Medivation, Inc. (AMEX: MDV) today announced that on September 27, 2006 it received permission from the FDA to begin the Company’s U.S. Phase 1-2a clinical trial of Dimebon™ in patients with Huntington’s disease. Medivation expects patient dosing to begin in early October.

Dimebon™ has been shown to prevent the death of brain cells (neurons) in preclinical models of Alzheimer’s disease and Huntington’s disease, making it a novel potential treatment for many neurodegenerative diseases. Dimebon recently met all five efficacy endpoints in a six-month randomized, double-blinded, placebo-controlled trial of 183 patients with mild to moderate Alzheimer’s disease. Patients in the trial were tested for a full spectrum of problems typically caused by Alzheimer’s disease, including memory loss, behavioral disturbances, and inability to perform everyday activities such as bathing and dressing. After six months of treatment, patients on Dimebon got significantly better on all of these tests. Dimebon patients also scored significantly better on all of these tests than did placebo patients. Dimebon, which has a 20-year record of human use, also was very well tolerated in this study. Medivation and its advisors designed this study to match closely the design of pivotal registration studies previously accepted by the FDA to approve currently marketed Alzheimer’s disease drugs, including duration of treatment, clinical endpoints and patient inclusion/exclusion criteria.

Medivation is conducting the Huntington’s disease study in collaboration with the Huntington Study Group (HSG), a network of more than 250 experienced clinical trial investigators, coordinators and consultants from more than 60 academic and research institutions throughout the United States, Canada, Europe and Australia. The study will be performed at approximately 12 HSG sites in the United States, and the principal investigator is Karl Kieburtz, MD, MPH, Professor of Neurology at the University of Rochester and the Director of the HSG Clinical Trials Coordination Center.

The Huntington’s disease clinical study has two parts – the first part is to assess the safety of various doses of Dimebon, and the second part is a randomized, double-blinded, placebo-controlled phase to assess the preliminary efficacy of Dimebon as a treatment for Huntington’s disease. Medivation will submit additional animal studies to the FDA before beginning the second part of the clinical trial, and expects to report clinical trial results in the second half of 2007.