By Ransdell Pierson
(Reuters) - Biogen Idec Inc's research chief on Tuesday said the company is planning a late-stage trial of its experimental treatment for Alzheimer's disease after the drug cut brain plaque levels and significantly improved cognition in a small early-stage study.
Shares of Biogen, whose main drugs treat multiple sclerosis, were up 6 percent in midday trading on the Nasdaq.
Douglas Williams, speaking at the Deutsche Bank BioFEST conference, said the encouraging data was seen in a Phase 1b trial of its BIIB037 drug. It was tested in patients with mild symptoms of the progressive neurological disease, or in those who did not yet have apparent symptoms but had other possible signs of Alzheimer's.
The medicine, like many other experimental Alzheimer's drugs that have failed in studies or are continuing to be tested, blocks beta amyloid, a protein that plays a key role in the buildup of toxic plaques in the brain that are considered a hallmark of Alzheimer's.
"We are preparing to implement a Phase III study in early Alzheimer's as soon as we can," company spokeswoman Kate Niazi-Sai said after Williams' presentation.
The most significant side effects seen with BIIB037 were signs of possible brain swelling and tiny hemorrhages, which the company described as "largely mild to moderate, and self-resolving."
Brain swelling has been a recurrent issue with experimental anti-amyloid Alzheimer's drugs, including with bapineuzumab from Pfizer Inc and solanezumab from Eli Lilly and Co. It has also been closely associated with an experimental class of drugs called gamma secretase inhibitors that have largely been abandoned.
Pfizer and its partner Johnson & Johnson discontinued bapineuzumab after it failed in big late-stage trials to significantly improve cognition in patients with mild to moderate Alzheimer's. But Lilly continues to test solananezumab in patients with mild Alzheimer's.
One of the biggest hopes for patients is another class of Alzheimer's drugs called BACE inhibitors. They block an enzyme called beta secretase which plays a key role in production of beta amyloid. Eli Lilly, Merck & Co are considered furthest along in testing such drugs.
As many as 5 million people in the United States and 36 million globally are believed to have Alzheimer's, the most common form of dementia. The U.S. figure for people 65 or older may triple by 2050 as the population ages, according to the Alzheimer's Association.
(Reporting by Ransdell Pierson; Editing by Lisa Von Ahn and Marguerita Choy)