Medivation drug improves Huntington's

WASHINGTON (Reuters) - Medivation Inc said on Monday its experimental drug, Dimebon, was shown in a mid-stage trial to significantly improve cognitive function in patients with Huntington's disease, sending the company's shares up 16 percent.

The study, involving 90 patients with mild-to-moderate Huntington's, also showed the drug was associated with favorable results on the behavioral segment of another scale measuring components of the neurodegenerative disease, but the results did not reach statistical significance.

Huntington's is a condition in which the degeneration of brain cells causes uncontrolled movement and loss of intellectual function.

The most common adverse event in the Dimebon group was headache, which occurred in 19 percent of treated patients compared with 7 percent of placebo patients, the company said.

Medivation said it is committed to aggressively advancing development of Dimebon as a treatment for Huntington's disease, which affects about 30,000 people in the United States.

Full results from the Phase II study will be submitted for presentation at an upcoming scientific meeting, the company said.

Meanwhile, Medivation is enrolling patients in a pivotal- stage trial of Dimebon in patients with mild-to-moderate Alzheimer's disease.

Analysts said the Huntington's disease results do not necessarily translate to other diseases.

"Huntington's disease and Alzheimer's are not the same disease," Roth Capital Partners analyst Andrew Valno said in a research note on Monday. "While Dimebon's purported neuroprotection mode of action may be similar in the two diseases, the diseases themselves are different enough in cause, progression and measurement that we are not convinced the result of this trial offers insight into the ability of Dimebon to treat Alzheimer's."