In two Phase 2 clinical trials evaluating the safety and efficacy of Roche's (OTCQX:RHHBY -1.1%) crenezumab as a treatment to delay cognitive and functional decline in patients with mild-to-moderate Alzheimer's disease (AD), the humanized monoclonal antibody failed to meet its co-primary endpoints in the larger study and only demonstrated "evidence of a treatment effect" in people with mild AD in both studies.
In the larger study, called ABBY, crenezumab-treated patients showed a trend toward slowing the decline of cognitive abilities as measured by ADAS-cog12, but no effect on global functioning measured by CDR-SOB. These were the co-primary endpoints. There was a positive trend towards increasing reduction in cognitive decline in progressively milder subsets compared to placebo, but this was an exploratory analysis.
The second smaller study, called BLAZE, subjects were enrolled that tested positive for an amyloid imaging biomarker. The primary endpoint was a change in brain amyloid load. Roche does not disclose whether the endpoint was achieved or not.