A widely-anticipated drug treatment for Alzheimer’s disease has shown promising results in clearing amyloid plaques from the brain in a phase 2 study – but questionable effects on cognitive outcomes.
Trial results for the Biogen/Eisei BAN2401 molecule were presented at the Alzheimer’s Association International Conference in Chicago on 25 July showing that the anti-amyloid drug produced dose-related effects on amyloid conversion and some cognitive measures.
The study, conducted in 800 patients with early Alzheimers disease and confirmed amyloid pathology confirmed compared five different dosing regimens of the drug with placebo over 18 months.
Over the study period, there was a dose dependent reduction in amyloid PET values by 0.30 units and a 70 unit reduction in Centiloid units compared to placebo. Likewise there was dose dependent conversion of patients from amyloid positive to negative compared to placebo, with an 81% conversion rate at the highest dose (10mg bi weekly) of BAN2401.
There was also a 30% slower rate of cognitive decline with the highest dose of BAN2401 compared to placebo, according to ADS-cog measures. However, the trial did not meet its primary endpoint for a significant effect on cognitive decline according to the ADCOMS measure .
Adverse effects leading to discontinuation occurred in 6.1% of placebo patients and 14.9% of patients taking the highest dose of BAN2401.
The study authors said this it was the first large clinical trial to support the amyloid hypothesis in Alzheimers, and the slowing in cognitive decline was clinically significant.