First Patient Treated In Phase 2 Trial Of Dimebon In Huntington's Disease

Armen Hareyan's picture

Huntington's Disease

Medivation announced treatment of the first patient in its Phase 2 trial of Dimebon to treat Huntington's disease.

Medivation has expanded patient enrollment in the trial by 20 percent -- to 90 patients -- in order to enhance the ability to detect differences between Dimebon and placebo.

"We are pleased that the results from the Phase 1 portion of our Huntington's disease study allow us to move forward to the preliminary efficacy phase," said David Hung, M.D., president and chief executive officer of Medivation. "Given the robust efficacy and safety results Dimebon achieved in our recently completed Alzheimer's disease trial, we are excited about Dimebon's potential to benefit Huntington's disease patients."


Medivation is conducting the Huntington's disease trial 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 Phase 2 portion will be conducted at approximately 17 HSG sites in the United States and Europe and is being led by principal investigator Karl Kieburtz, M.D., M.P.H., professor of neurology at the University of Rochester and director of the HSG Clinical Trials Coordination Center.

The Phase 2 study is a randomized, placebo-controlled, double-blinded evaluation of the safety and preliminary efficacy of Dimebon in 90 Huntington's disease patients after three-months of dosing. The primary efficacy endpoint of the Phase 2 portion is the Unified Huntington's Disease Rating Scale (UHDRS). Medivation expects to report study data in the first half of 2008.

Huntington's disease is a progressive, neurodegenerative disease that affects 30,000 patients in the U.S., with another 150,000 at risk. It is caused by the death of specific brain cells and is characterized by the gradual development of involuntary muscle movements, progressive deterioration of cognitive processes and memory (dementia), and severe behavioral disturbances. There are no drugs approved by the FDA to treat this uniformly fatal genetic disorder.

Dimebon is an orally-available small molecule that has been shown to prevent the death of brain cells in preclinical models of Alzheimer's disease and Huntington's disease, making it a novel potential treatment for these and other neurodegenerative diseases. Based on the clinical and preclinical data generated to date, Medivation believes that Dimebon operates by a novel mechanism of action and may exert a neuroprotective effect in multiple areas of the central nervous system. Dimebon appears to block a new target that involves mitochondrial pores, which are thought to play a role in the cell death that is associated with neurodegenerative diseases and the aging process.

In a randomized, double-blinded, placebo-controlled trial of 183 patients with mild to moderate Alzheimer's disease, Dimebon-treated patients were significantly improved over placebo on all five clinical endpoints at 6 months, including cognition and memory, activities of daily living, overall function, and behavior. Recently-announced results from patients continuing this study showed that Dimebon sustained significant improvement over placebo on every endpoint through one year of treatment. Dimebon was well tolerated throughout the entire one-year period.