Hopes rise again for a drug to slow Alzheimer’s disease

CHICAGO (AP) — Hopes are rising again for a drug to alter the course of Alzheimer’s disease after decades of failures. An experimental therapy slowed mental decline by 30 percent in patients who got the highest dose in a mid-stage study, and it removed much of the sticky plaque gumming up their brains, the drug’s makers said Wednesday.

The results have been highly anticipated and have sent the stock of the two companies involved soaring in recent weeks.

The drug from Eisai and Biogen did not meet its main goal in a study of 856 participants, so overall, it was considered a flop. But company officials said that 161 people who got the highest dose every two weeks for 18 months did significantly better than 245 people who were given a dummy treatment.

There are lots of caveats about the work, which was led by company scientists rather than academic researchers and not reviewed by outside experts. The study also was too small to be definitive and the results need to be confirmed with more work, dementia experts said. But they welcomed any glimmer of success after multiple failures.

“We’re cautiously optimistic,” said Maria Carrillo, chief science officer of the Alzheimer’s Association, whose international conference in Chicago featured the results.

“A 30 percent slowing of decline is something I would want my family member to have,” and the drug’s ability to clear the brain plaques “looks pretty amazing,” she said. About 50 million people worldwide have dementia, and Alzheimer’s is the most common type. There is no cure— current medicines just ease symptoms. Some previous efforts to develop a drug to slow the disease may have been tried too late, after much damage had already occurred. The new drug aimed sooner, in people with early Alzheimer’s, and the drug works at an earlier step in formation of the sticky brain plaques. Study participants were given one of five doses of BAN2401 or a dummy treatment via IV. After one year, the companies said the drug didn’t meet statistical goals. But after 18 months, they saw a benefit in the highest dose group.

What makes it tricky, though, is that they used a new way to measure mental decline, a scale that combines parts of three other widely used tests. This is the first study to use that measure, and it’s unclear how much of a difference a 30 percent slowing of decline makes — whether it allows someone to continue to bathe or feed himself, for instance.