AC Immune says Parkinson's drug slows progression
AC Immune's chief executive, Dr Andrea Pfeifer.
Swiss biotech AC Immune has said that its vaccine-like alpha-synuclein-targeted immunotherapy has shown promise in slowing down the progression of Parkinson's disease.
The results of the phase 2 VacSYn trial of ACI-7104.056 in patients with early-stage Parkinson's have shown that the immunotherapy can reduce disease-related biomarkers – namely alpha-synuclein levels in the cerebrospinal fluids (CSF) and neurofilament light (NfL) – that AC Immune said point to a "stabilisation" of the Parkinson's disease process.
Imaging data from the trial, looking at GFAP and DaT biomarkers that respectively track the activation of neuron-repairing glial cells in the central nervous system and the loss of dopaminergic neurons, also "show trends toward disease modification," it added. And finally, there was also a trend towards stabilised symptoms using the MDS-UPDRS scale.
"The remarkable consistency of the trends observed across multiple disease-related biomarkers and on clinical assessments in the treatment arm are very promising," commented Parkinson's expert Werner Poewe of Innsbruck Medical University.
"For the first time, we are seeing signals that targeting the underlying pathology of Parkinson's with active immunotherapy could slow disease progression."
Final data from this stage of the VacSYn trial is expected in mid-2026, said AC Immune.
Alpha-synuclein is a protein that tends to get misfolded and accumulates into clumps in the brains of patients with Parkinson's and other neurodegenerative diseases like multiple system atrophy (MSA), and is somewhat analogous to amyloid and tau proteins in Alzheimer's disease.
The positive results come after antibody-based, alpha-synuclein-directed drugs posted disappointing results in Parkinson's, including Roche's prasinezumab and Biogen's cinpanemab, while Lundbeck's AF82422 failed to hit the mark in an MSA trial.
They also follow a decision by AC Immune to slash staff and R&D programmes in order to focus on ACI-7104.056 and two other immunotherapies for Alzheimer's, anti-amyloid therapy ACI-24.060 and tau-directed ACI-35.030, which are partnered with Takeda and Johnson & Johnson, respectively.
The company said the restructuring would extend its cash runway out to the third quarter of 2027, after the readout of a phase 2 trial of ACI-24.060.
Chief executive Dr Andrea Pfeifer said the new data holds "the promise of a tremendous step forward for millions of patients."
She added that the consistent signs of efficacy, combined with the continuing strong safety record, underline ACI-7104.056's potential to transform treatment, and the company intends to accelerate development of the drug and "discuss ACI-7104.056 with […] regulators to establish a clinical development plan towards registration."
AC Immune's Nasdaq-listed shares had risen around 10% at the time of writing in the wake of the announcement.
