In a first for the Parkinson’s field, AC Immune’s immunotherapy has stabilized key biomarkers that suggest an effect on the disease’s course.
An immunotherapy developed by AC Immune appeared to slow the progression of Parkinson’s disease in a mid-stage trial, representing a first for the disease and a key win for the biotech which tackles intractable neurodegenerative disorders.
In part one of the Phase II VacSYn trial, AC Immune’s anti-alpha-synuclein (a-syn) active immunotherapy, ACI-7104.056, was tested against placebo in 34 patients with early Parkinson’s disease for at least 12 months. Twenty participants stayed on treatment for 18 months.
At the interim analysis, AC Immune found that the immunotherapy stabilized known Parkinson’s biomarkers such as a-syn and neurofilament light chain, which are signs of neuronal damage or neurodegeneration in the brain.
Brain imaging after treatment suggested “trends toward disease modification,” the company said in a press release Thursday, and there was a suggested trend of stabilization on patient-reported movement scores. ACI-7104.056 also induced a robust antibody response in all patients at week 76.
Shares of AC Immune rose 14% to $3.17 in pre-market trading on Thursday morning, but stablized once trading began to $2.90.
“For the first time, we are seeing signals that targeting the underlying pathology of Parkinson’s with active immunotherapy could slow disease progression,” Werner Poewe, emeritus Professor of Neurology at Innsbruck Medical University and an expert in Parkinson’s disease, said in the same press release.
AC Immune will need to layer on the evidence to show that ACI-7104.056 can impact the underlying disease, Poewe noted. But today’s results are “highly encouraging,” he said.
CEO Andrea Pfeifer said the results “hold the promise of a tremendous step forward for millions of patients.”
AC Immune trimmed its pipeline earlier this year in an effort to extend its cash runway into the third quarter of 2027 and focus on the most important assets in the pipeline—ACI-7104.056 included. At the same time, 30% of staff were let go.
Another focus is ACI-24.060, a vaccine for Alzheimer’s disease that targets abeta and has been dubbed a “first mover effort” by HCW Research analysts. The biotech is expecting a readout for the program in the first half of 2026.
