UPDATE 1-Pfizer, Medivation to stop study on Huntington disease drug

* To stop trials of drug in this indiaction

* To continue study of drug for Alzheimer’s

* Expect to report top-line data in Alzeimer’s study in H1
2012

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April 11 (Reuters) – Pfizer Inc and Medivation Inc
said they will halt the development of their closely
watched experimental drug after it failed to show statistically
significant improvement in patients with Huntington disease,
which causes a loss of brain cells and mental deterioration.

The failed late-stage trial showed there was no
statistically significant improvement in patients taking the
drug dimebon compared with those taking a dummy pill. However,
the drug was generally well tolerated.

“We are disappointed with the results of the HORIZON trial,
given the high unmet need in this patient population. At this
point, we will discontinue development of dimebon in Huntington
disease, including the ongoing open-label extension study,”
Medivation’s Chief Executive David Hungo said in a statement.

The drug is currently in another late-stage trial for
patients with mild-to-moderate Alzheimer’s disease, and the
companies expect to report top-line data from the study in the
first half of 2012.

Shares of Medivation were trading down 3 percent at $19.45
before-the-bell on Monday. They closed at $20.11 on Friday on
Nasdaq. Pfizer shares closed at $20.46 on Friday on the New York
Stock Exchange.

(Reporting by Krishnakali Sengupta in Bangalore; Editing by
Roshni Menon)

UPDATE 1-Pfizer, Medivation to stop study on Huntington disease drug