Landmark for AC Immune Alzheimer and Down Syndrome vaccines

Published: 21-Aug-2018

The swiss clinical stage biopharmaceutical company has a broad pipeline focused on neurodegenerative diseases

AC Immune, a Switzerland-based, clinical-stage biopharmaceutical company has announced two clinical milestone events related to ACI-24, its anti-Abeta vaccine against Alzheimer's disease and Abeta-related cognitive decline in Down Syndrome.

Professor Andrea Pfeifer, CEO of AC Immune, said: "We are delighted with the progress of ACI-24, the anti-Abeta vaccine, derived from our proprietary SupraAntigen platform."

"In addition to the development in Alzheimer's Disease, it is currently the only clinical-stage vaccine targeting the associated Abeta-induced cognitive decline in people with Down Syndrome. Vaccines are potentially an important option for the treatment and prevention of neurodegenerative diseases and are a key asset in our pipeline."

AC Immune has started the Phase II study with ACI-24 in patients with mild Alzheimer's disease. The aim of this double-blind, randomised, placebo-controlled study with an adaptive design is to assess the safety, tolerability, immunogenicity, target engagement, biomarkers and clinical efficacy of ACI-24.

The trial will seek to confirm the positive trends on Abeta positron emission tomography imaging and clinical measurement (clinical dementia rating-sum of boxes) of the previous Phase I safety study. The Phase II trial will be conducted in several European countries and the first patients have been screened.

AC Immune has completed recruitment for the high-dose cohort of the ACI-24 Phase Ib study for the treatment of Alzheimer's disease-like characteristics in adults with Down Syndrome, a condition affecting approximately one in 700 newborns.

The first low-dose and the second high-dose cohorts have been fully recruited in August 2017 and in July 2018 respectively, and interim results of the low dose cohort are expected later in 2018. In addition to cognitive dysfunction beginning in childhood, individuals with Down Syndrome are genetically-predisposed to develop Abeta-related cognitive decline at a much younger age and with much greater probability than the general population.

Vaccines are potentially an important option for the treatment and prevention of neurodegenerative diseases with high market potential. AC Immune's promising pipeline of Abeta and Tau targeted therapies includes new diagnostic and treatment options, including various vaccines.

ACI-24 is the company's first vaccine entering in Phase II development. It enhances AC Immune's late stage clinical pipeline, containing one Phase III and multiple Phase II product candidates. AC Immune believe the pipeline is therefore well positioned to target both Abeta and Tau in a combined approach for a disease-modifying Alzheimer's disease treatment.

ACI-24 is a liposomal therapeutic anti-Abeta vaccine candidate, which generates antibodies specific to disease-causing conformations. The vaccine is designed to stimulate a patient's immune system to produce antibodies that specifically target the oligomeric and fibrillary Abeta proteins to prevent plaque accumulation and to enhance plaque clearance.

Preclinical data demonstrated a significant activity in plaque reduction and memory restoration as well as a favorable safety profile characterised by a lack of local inflammation and a mode of action independent of T-cells.

The vaccine is being studied in a Phase II clinical trial in patients with mild to moderate Alzheimer's Disease and in a Phase Ib study in young adult Down Syndrome subjects, and has been proven to be safe with preliminary trends of efficacy.


  1. World Health Organization (WHO); Alzheimer's Disease International (ADI)
  2. Head E, Powell D, Gold BT, Schmitt FA. Alzheimer's Disease in Down Syndrome. European journal of neurodegenerative disease. 1(3):353-364. 2012
  3. Castro P, Zaman S, Holland A. Alzheimer's disease in people with Down's syndrome: the prospects for and the challenges of developing preventative treatments. Journal of Neurology. 264(4):804-813. 2017.
  4. Presson AP, Partyka G, Jensen KM, Devine OJ, Rasmussen SA, McCabe LL, McCabe ER.Parker. Current estimate of Down Syndrome population prevalence in the United States. The Journal of Pediatrics. 163(4):1163-8. 2013.

You may also like