Prestwick Pharmaceuticals, Inc, a privately-held pharmaceutical company, announced that the US Food and Drug Administration (FDA) has approved Xenazine (tetrabenazine) for the treatment of chorea associated with Huntington's disease (HD). Xenazine is the first and only FDA-approved treatment for any symptom of HD and is expected to be available later this year.

"Until now, physicians and patients had no FDA-approved treatments for Huntington's disease," said Fred Marshall, MD, chief of the geriatric neurology unit at the University of Rochester. "Within a few months, for the first time, physicians will be able to offer these critically-ill patients a safe and effective medication to treat their chorea."

A double-blind, placebo-controlled, phase-3 study found that Xenazine significantly reduced patients' chorea burden, improved global outcome scores, and was generally safe and well tolerated. Xenazine will be marketed under an FDA-approved Risk Evaluation and Mitigation Strategy to decrease the risk of depression and suicidal ideation that may be associated with the drug, and are often pre-existing conditions in Huntington's disease patients.

In December 2007, patients, advocates, and caregivers spoke in favour of approving Xenazine at a meeting of the FDA's Peripheral and Central Nervous System Drugs Advisory Committee. The committee voted 11-0 to recommend approval of the drug.

"We are pleased that the FDA has approved Xenazine, the first medication for the Huntington's disease patients and physicians who are in desperate need of a treatment," said George F Horner, III, president and chief executive officer of Prestwick. "The approval of Xenazine is a huge advancement for the HD community, and we thank them for their contributions in helping to make this important product available in the United States." Xenazine has been available in a number of countries in Europe for more than 30 years.

Affecting an estimated 30,000 Americans, Huntington's disease is a devastating neurodegenerative disease that causes progressive movement disorders, cognitive dysfunction and behavioural changes and is ultimately a fatal condition. Chorea is the most common symptom, affecting approximately 90 per cent of HD patients, and is characterized by excessive, involuntary and repetitive movements, which are the most visible and dangerous manifestations of HD and interfere with patients' abilities to perform activities of daily living, including dressing, bathing and caring for themselves.

Xenazine is indicated for the treatment of chorea associated with Huntington's disease. A selective and reversible centrally-acting dopamine depleting drug, Xenazine works by inhibiting a molecule known as VMAT2 (vesicular monoamine transporter 2).

Prestwick Pharmaceuticals, a privately-held pharmaceutical company headquartered in Washington, DC, is currently managing product candidates for CNS conditions with significant unmet needs, including Huntington's disease, schizophrenia, and sleep apnoea.