Swiss biotech AC Immune released interim Phase II biomarker data from its active immunotherapy Vacsyn (ACI‑7104) that the company says show consistent α‑synuclein, neurofilament light (NfL) and imaging changes consistent with potential disease modification in early Parkinson’s disease. The biomarker suite — CSF α‑syn, NfL, GFAP and DAT‑SPECT signals — prompted AC Immune to indicate plans for regulator engagement to accelerate development timelines. Company statements and conference disclosures emphasized the coherence of multiple biomarker modalities rather than a definitive clinical benefit at this stage. AC Immune’s management framed the dataset as support for moving to confirmatory studies with regulatory input on endpoints and accelerated pathways. Investors rewarded the announcement with double-digit share moves; scientists and clinicians urged caution until clinical endpoints are clarified. Still, the readout represents one of the more substantive biomarker-led cases for an α‑syn targeting strategy and may shape design choices for other neurodegeneration immunotherapies.