A large trial of an experimental Alzheimer’s disease drug has shown promise in slowing cognitive decline over a period of 18 months, marking one of the first successful human trials of an anti-amyloid treatment.
Biogen and Eisai released their results in an announcement on Tuesday, which showed a 27 percent reduction in the progress of Alzheimer’s disease with the drug compared to placebo. Following a series of disastrous anti-amyloid drug trials, the results couldn’t have come at a better time.
According to Eisai, the results may finally add some concrete evidence supporting the amyloid hypothesis.
“Additionally, the lecanemab Clarity AD study results prove the amyloid hypothesis, in which the abnormal accumulation of Aβ in the brain is one of the main causes of Alzheimer’s disease, when targeted with a protofibril-binding therapy,” said Haruo Naito, Chief Executive Officer at Eisai, in a statement.
"Eisai believes these findings will create new horizons in the diagnosis and treatment of Alzheimer’s disease as well as further activate innovation for new treatment options.”
The drug itself is called lecanemab, an anti-amyloid beta (Aβ) protofibril antibody treatment that targets plaques of misfolded protein in the brain, which are thought to lead to the cognitive impairment seen in Alzheimer’s and Alzheimer’s-like diseases.
The trial recruited almost 1,800 participants with the presence of amyloid plaques in the brain, and the study endpoint was a significant slowing of disease progression.
After 18 months, the study showed a 27 percent reduction in clinical decline compared to placebo, with significant results shown as early as six months in.
When it came to adverse effects, amyloid-related imaging abnormalities-edema/effusion (ARIA-E) (an antibody-related accumulation of fluid in the brain) was increased significantly above placebo groups, with 12.5 percent of the lecanemab group experiencing it compared to just 1.7 percent in the placebo group. Of these, 2.8 percent experienced symptoms in the lecanemab group while none of the placebo group had symptoms.
The team will now push for approval in US and Japanese markets following the promising Phase 3 trial results, but the implications they have for Alzheimer’s research are arguably considerable.
“Importantly, the study shows that removal of aggregated amyloid beta in the brain is associated with a slowing of disease in patients at the early stage of the disease. We want to thank the many patients who participated in this groundbreaking global study and want to acknowledge the clinical investigators who worked tirelessly to increase the enrollment of traditionally underrepresented populations,” said Michel Vounatsos, Chief Executive Officer at Biogen, in a statement.