FDA approves 1st therapy to help ease Huntington's

WASHINGTON (Reuters) - U.S. health officials have approved the first drug aimed at easing symptoms of Huntington's disease, an incurable neurological disorder that can cause uncontrollable movements.

The drug, called Xenazine, does not treat the hereditary disease. It is instead designed to help quell the jerky, involuntary body movements that can increase as brain cells waste away, the U.S. Food and Drug Administration said on Friday.

While clinical trials showed the drug can help improve movement short-term, they also found it can worsen a patient's mood as well as mental functions like cognition, the FDA said.

Other side effects included insomnia, depression, drowsiness and nausea, according to the agency.

Xenazine, made by privately held Prestwick Pharmaceuticals Inc, works by decreasing the amount of the natural chemical dopamine, which helps control nerve cells in the brain. In Huntington's patients the interaction can be too active and trigger abnormal movement.

Those with the degenerative disease can also experience emotional problems and mental decline.

Huntington's is rare, affecting roughly 30,000 people in the United States, according to the FDA. The disease progresses slowly, allowing patients to live 10 to 20 years after symptoms develop. Most signs of the disease occur between ages 30 and 50.

(Reporting by Susan Heavey, editing by Gerald E. McCormick)