Pfizer, Medivation End Alzheimer Drug’s Work After Failure

Pfizer Inc. (PFE) and Medivation Inc. (MDVN) ended their collaboration on the experimental drug Dimebon for Alzheimer’s disease after the medicine failed in another late- stage clinical trial.

Dimebon was one of two drugs New York-based Pfizer had in its late-stage pipeline to treat the neurodegenerative disease. The other is bapineuzumab, which Pfizer is developing with Johnson & Johnson. The treatments have different mechanisms of action.

Dimebon didn’t show statistically significant results in a study that evaluated the compound when added to a standard treatment in patients with mild to moderate forms of the disease, the companies said today in a statement. The companies will end development of the drug for all uses, and will stop a current study.

Medivation, based in San Francisco, dropped 3.3 percent to $53.90 at the close in New York. Pfizer, the world’s biggest drugmaker, gained less than 1 percent to $21.94.

Dimebon also failed in a late-stage trial in 2010, sending Medivation shares down 67 percent in one day.

The U.S. Centers for Disease Control and Prevention in Atlanta estimates that at least 5 million Americans have Alzheimer’s. The disease usually begins affecting people around age 60. There is no known cure.

To contact the reporter on this story: Drew Armstrong in New York at

To contact the editor responsible for this story: Reg Gale at

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