Swiss based AC Immune reported in January 2023 that ACI-24.060, its anti-amyloid-beta (Abeta) vaccine, had “elicited an anti-Abeta antibody response” and was “well tolerated” in patients with prodromal Alzheimer’s disease (AD). It will therefore move to a second cohort in the ABATE trial.
The trial is a Phase Ib/II multicentre, adaptive, double-blind, randomised, placebo-controlled study to assess the “safety, tolerability, immunogenicity, and pharmacodynamic effects” of the vaccine candidate ACI-24.060 in subjects “with prodromal Alzheimer’s disease and in adults with Down syndrome”. Participants were required to have brain Abeta pathology confirmed by a positron emission tomography (PET) scan.
The trial will now be “expanded, as planned” to include individuals with Down syndrome and to “evaluate higher doses in Alzheimer’s patients”. Early results showed that a low dose of the vaccine could elicit an anti-Abeta antibody response “as soon as week 6”, which is 2 weeks after the second injection.
ACI-24.060 is “derived from AC Immune’s SupraAntigen platform” and has already demonstrated an ability to “induce a strong polyclonal antibody response that matures and is maintained against both oligomeric and pyroglutamate-Abeta species”. These are “key pathological forms of Abeta”, associated with Abeta plaque formation and disease progression.
The vaccine is designed to “enhance the formation of broad-spectrum protective antibodies” with the “same safety and tolerability previously demonstrated” in the ACI-24 programme.
“This investigational candidate has the potential to efficiently inhibit plaque formation and increase plaque clearance, and thereby may reduce or prevent disease progression.”
An approved approach
AC Immune states that “targeting Abeta using antibodies has recently been validated with FDA approvals of new monoclonal antibody treatments for patients with AD”. The vaccine programme is intended to “ultimately deliver significant benefits to patients, their caregivers, and healthcare systems”. With “safety and tolerability” meeting “low frequency dosing, low overall costs, and durable responses” it is hoped that this could become a reality.
Dr Andrea Pfeifer, CEO of AC Immune SA is “delighted with the encouraging initial safety and immunogenicity findings”.
“We believe ACI-24.060’s successful development could provide patients with a novel therapeutic option offering numerous potential advantages in treatment, maintenance, and prevention settings.”
Dr Johannes Streffer, CMO of AC Immune SA, suggested that the “innovative” design of the study with provide an opportunity for “early de-risking”.
“Moreover, the inclusion of cohorts of participants with DS in the trial positions us to potentially address the needs of a vastly underserved vulnerable population, virtually all of whom will develop amyloid plaques and AD.”
He thanked trial participants and investigators for their continued efforts.