Artist's rendering of a brain cell damaged by amyloid beta plaque in Alzheimer's disease

A drug tested for over a decade in patients with early-onset Alzheimer’s did not slow or prevent cognitive decline, Swiss drugmaker Roche announced late last week.

The new findings for crenezumab are another blow to a dominant research theory that targeting brain beta amyloid plaques may alter the Alzheimer’s disease course, according to observers. 

Crenezumab’s trial was unique in that it focused on early intervention for people with a specific genetic mutation that causes early-onset disease. The 252 participants were all traced to one family line. Most had a mutation that can cause Alzheimer’s-related cognitive impairment beginning around 44 years of age, FierceBioTech reported.

The hope was that earlier intervention would be the key to the drug’s success.  The current trial had run for more than a decade, Roche said in a statement.

Only one amyloid-focused drug has gained federal approval for treating dementia after decades of Alzheimer’s research. Yet Biogen’s Aduhlem has not gained support in the clinical community due to questions about its efficacy, safety and cost issues.

Other pharmaceutical companies have been inspired to move forward with Alzheimer’s drug candidates after Aduhelm was approved in the United States. Eli Lilly amyloid-busting drug donanemab is in the pipeline for federal review. And Genentech’s gantenerumab could be the next Alzheimer’s-modifying therapy in line for FDA approval, according to market research firm Spherix.

“We’re disappointed that the treatment did not demonstrate a statistically significant clinical benefit,” said co-study leader Eric M. Reiman, M.D., executive director of Banner Alzheimer’s Institute. “At the same time, we’re proud of the impact that this precedent-setting trial has had in shaping a new era in Alzheimer’s prevention research and we’re extremely grateful to our research participants and their families.”