Treatment Reduced Amyloid Levels
In addition, BAN2401 failed to meet its 12-month prespecified primary cognitive end points. The investigators reached this conclusion through Bayesian analysis that strove to predict an 80% probability of achieving at least a 25% cognitive benefit. In December 2017, Eisai announced that the treatment had reached 64% probability. Because the company was optimistic about the treatment’s success, it continued with the additional six months of treatment, as the study design allowed, and reanalyzed results with a simpler and more straightforward method. This analysis concluded that the 10-mg/kg biweekly dose slowed decline on the Alzheimer’s Disease Composite Score (ADCOMS), a new tool developed and promoted by Eisai, by 30%. It also found that treatment slowed decline on the Alzheimer’s Disease Assessment Scale-cognitive subscale (ADAS-Cog) by 47%. Treatment cleared brain amyloid in 81% of subjects and had positive effects on CSF biomarkers. CSF amyloid levels increased, and CSF total tau levels decreased, which indicated decreased neuronal injury.
—Michele G. Sullivan