CHICAGO — Hopes are rising again for a drug to alter the course of Alzheimer’s disease after repeated failures.

Two drug companies said that an experimental therapy they are developing slowed mental decline by 30 per cent in patients who got the highest dose. It also removed much of the sticky plaque gumming up their brains.

Alzheimer’s is the most common form of dementia, and current drugs just ease symptoms.

The new drug is called BAN2401, from Eisai and Biogen. It failed to help in a study of 856 people with early Alzheimer’s, but those who got the highest of five doses for 18 months declined less than those given dummy treatments.

Results were revealed Wednesday at the Alzheimer’s conference in Chicago.

Marilynn Marchione, The Associated Press

Filed under: Alzheimer's, ban2401, Dementia, new-drug