AC Immune announced positive interim biomarker and safety signals from its Phase II Vacsyn trial of ACI-7104.056, an active immunotherapy targeting alpha‑synuclein in early Parkinson’s disease. The company reported coherent changes across cerebrospinal fluid alpha‑synuclein, neurofilament light (NfL), GFAP and DaT‑SPECT imaging that it says are consistent with potential disease slowing. Management said it will seek regulator feedback to accelerate an approval path, citing the biomarker suite as the rationale. Independent analysts cautioned that biomarker shifts do not yet equate to clinical benefit; the company acknowledged clinical endpoints remain immature. AC Immune’s share moves reflected investor optimism on a disease‑modifying signal but highlighted the wider industry tension around biomarker‑driven filings. The readouts add to a crowded neurodegeneration pipeline where regulators increasingly confront requests to accept surrogate endpoints. Trialists and payers will demand confirmatory clinical outcomes before broad adoption, while the data may prompt partnerships and licensing interest for late‑stage development.