Alpha-Synuclein SAA Predicts Parkinson’s Levodopa Response Durability
A 2026 PPMI analysis found that Parkinson’s patients with positive CSF α-synuclein seed amplification assay results kept gaining levodopa benefit over follow-up, while SAA-negative patients showed faster ON-medication motor progression than SAA-positive patients: 0.87 vs. 3.47 MDS-UPDRS Part III points/year in 183 matched SAA-positive and 40 SAA-negative patients.1 Research Highlights ON-state progression split sharply: SAA-positive …