Roche announced new data from its Alzheimer's portfolio at the AD/PD 2025 conference. The trontinemab Phase Ib/IIa study showed rapid, dose-dependent amyloid plaque reduction in the brain. 81% of participants in the 3.6 mg/kg dose group reached below the amyloid positivity threshold after 28 weeks. This reduction was supported by significant decreases in fluid biomarkers of Alzheimer's. Trontinemab demonstrated a favorable safety profile with low ARIA-E incidence. Roche plans to initiate a Phase III program for trontinemab later this year. The Elecsys pTau181 plasma test showed potential for accurately ruling out amyloid pathology. This could reduce the need for invasive CSF or PET scans, improving diagnosis efficiency. The Elecsys pTau181 test is expected to be available in Europe by late 2025, followed by the U.S. The Phase IIb PADOVA study of prasinezumab in early Parkinson's disease missed its primary endpoint, but showed potential benefit in levodopa-treated patients. Roche is evaluating the data to determine next steps for prasinezumab.