Pfizer Inc. and Medivation Inc. 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.