Parkinson's data suggests ACI-7104.056 could slow progression

Swiss clinical-stage biotech AC Immune (Nasdaq: ACIU) today announced positive interim safety and efficacy results from the Phase II VacSYn trial of its wholly-owned anti-alpha-synuclein (a-syn) active immunotherapy ACI-7104.056 in early Parkinson’s disease (PD), sending its share up more than 40% in pre-market activity, although they dropped as full trading got underway.

The company noted that results show, for the first time, that targeting a-syn pathology with an active immunotherapy could potentially slow the rate of progression of PD. Disease-related biomarker results, including a-syn CSF levels and neurofilament light (NfL), suggest stabilization of PD pathology. Plasma glial fibrillary acidic protein (GFAP) and dopamine transporter (DaT) SPECT imaging show trends toward disease modification. In addition, total scores on Part III of the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) are suggestive of a trend for stabilization.

Based on these promising interim results, AC Immune aims to seek regulatory feedback on an ACI-7104.056 clinical development plan to potentially accelerate towards registration. Final data from Part 1 of the VacSYn trial are expected in mid-2026.