Ceperognastat, an oral small-molecule inhibitor targeting OGA (O-linked N-acetylglucosaminidase), failed to show a measurable clinical impact in a JAMA trial evaluating early symptomatic Alzheimer's disease. Despite the biochemical premise of altering O-GlcNAc-related pathways, the study did not demonstrate clear slowing of disease progression among treated patients. The result underscores the difficulty of translating mechanism-based approaches into clinically meaningful endpoints in early Alzheimer’s, where effect sizes can be smaller and study duration and patient selection become decisive. For pipeline teams, the read-through is likely to strengthen the demand for confirmatory biomarkers and tighter alignment between target engagement and outcome measures as oral small molecules compete with antibody and other biologic modalities.