AC Immune has reported positive initial interim data from the Phase Ib/II ABATE trial of its ACI-24.060 anti-amyloid-beta (Abeta) vaccine in prodromal Alzheimer’s disease (AD) patients.

The randomised, adaptive, placebo-controlled, multicentre, double-blind ABATE study was designed for evaluating the immunogenicity, safety, pharmacodynamic effects, and tolerability of ACI-24.060 in prodromal AD patients and Down syndrome (DS) adult patients.

The findings showed that the ACI-24.060 vaccine elicited an anti-Abeta antibody response in ABATE’s first, low dose cohort of AD patients at week six.

It was also found to be well tolerated and safe till date.

Now, the ABATE study will be expanded to include DS patients and assess higher doses of the ACI-24.060 vaccine in AD patients.

AC Immune stated that dosing has now commenced in the ABATE study’s second, higher dose AD cohort, with these initial findings.

The screening of DS participants for the second part of the study is also cleared to begin.

AC Immune chief medical officer Dr Johannes Streffer said: “ABATE’s innovative design includes interim Abeta PET imaging analyses that can be benchmarked against the levels of plaque clearance achieved with clinically-validated monoclonal antibodies.

“This will provide an opportunity for early de-risking of ACI-24.060 and potentially a rapid transition to a pivotal programme.

“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.”

The company expects to receive further safety and immunogenicity findings from ABATE cohorts in the second half of this year.