A PHASE 2 trial involving an investigational monoclonal antibody drug, semorinemab, targeting the tau protein, reduced cognitive decline among adults with mild-to-moderate Alzheimer’s disease by about 44 percent, Swiss biotech AC Immune announced Tuesday.

Findings from the placebo-controlled study Lauriet stemmed from 272 adults with mild-to-moderate Alzheimer’s disease across 43 study sites worldwide. Results indicated the drug, developed by Genentech (member of the Roche Group) resulted in a “statistically significant reduction in cognitive decline” by 43.6 percent at week 49, however the drug failed to slow the rate of functional decline or meet other efficacy endpoints. The drug was suggested to be safe and well-tolerated, without unanticipated safety signals, according to a company release posted Tuesday.

The tau protein is one several factors believed to contribute to Alzheimer’s disease when it aggregates into toxic tangles, which can damage cells and kill neurons. The antibody drug semorinemab works by targeting a portion of the tau protein, binding to tau and slowing the spread between neurons, the company said.

“The top line results of the Lauriet Phase 2 clinical trial of semorinemab are remarkable in that it is the first time we have seen a therapeutic effect by a monoclonal anti-Tau antibody therapy,” Andrea Pfeifer, CEO of AC Immune SA, said in part in the release.

“Nevertheless, despite these interesting results, we are still cautious about what this may mean for patients as there was not an impact on the rate of functional decline or other efficacy endpoints,” Pfeifer said.

Genentech said the open-label study portion will proceed as planned, and results will be submitted to appear at the Clinical Trials on Alzheimer’s Disease conference in November, according to AC Immune.

(SD-Agencies)