Aducanumab treatment was associated with unusually striking, progressive, dose-dependent reductions in PET measurements of Aβ-plaque burden. Aducanumab was also presumed to bind to and remove harder-to-measure Aβ oligomers, which seem to accumulate at or near plaques and may be the more damaging of the two aggregates3. What's more, despite the relatively small number of study participants and the substantial extent to which the disease has progressed by the time people with Alzheimer's develop memory and thinking problems, exploratory analyses suggested that higher antibody doses and greater Aβ-plaque reductions were associated with slower cognitive decline. If these preliminary cognitive findings are confirmed in larger and more-definitive clinical trials, which are now under way, it would provide a shot in the arm in the fight against Alzheimer's disease and compelling support for the amyloid hypothesis.

First Alzheimer's clinical trial that shows actual promise, very exciting.