Biogen's stock surged Friday after the biotechnology company's experimental drug for Alzheimer's disease exceeded already high expectations in an early study.
The medicine, known as BIIB037, or aducanumab, showed both reductions in levels of the amyloid plaques in the brain associated with Alzheimer's, and a significant slowing of the disease's hallmark cognitive declines, Biogen reported at a conference in Nice, France.(Tweet This)
On one measure of cognition, known as CDR, for Clinical Dementia Rating, Biogen's drug showed a 71 percent reduction in declines on the highest dose. Analysts said they were looking for 20 percent to 30 percent reductions to qualify as a success.
"This is the first time an investigational drug for Alzheimer's disease has demonstrated a statistically significant reduction on amyloid plaque as well as a statistically significant slowing of clinical impairment in patients with prodromal or mild disease," Biogen Chief Medical Officer Dr. Al Sandrock said in a statement.
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The company said it's moving the drug into a late-stage study, with planned enrollment in the trial starting later this year. Even though there remains risks in the later stages of the drug's development, analysts expect that if all goes well, the drug could reach the market as early as 2018.
More than 5 million Americans are estimated to have Alzheimer's, a number that could triple by 2050, according to the Alzheimer's Association. It's the sixth-leading cause of death in the U.S.