AC Immune released interim biomarker results from its Phase II Vacsyn trial of the active α‑synuclein vaccine ACI‑7104, reporting changes in cerebrospinal fluid α‑synuclein and supportive neurodegeneration markers (NfL, GFAP) alongside favorable imaging signals. The company said the biomarker suite suggests a potential disease‑modifying effect and that it will seek regulatory feedback to accelerate development timelines. AC Immune also reported data that will underpin planned discussions with regulators about next‑step study design. The findings do not yet demonstrate clear clinical benefit, but the biomarker pattern is being framed as supportive evidence for moving toward late‑stage testing and for prioritizing endpoints in future trials.