Axial Therapeutics is set to increase the age eligibility criterion for its Phase llb study of AB-2004 for the treatment of irritability associated with autism spectrum disorder (ASD).

Part of a protocol amendment process, the expansion will include autistic children aged five to 17 years. Previously, the trial restricted subjects within the age group of 13 to 17 years.

The global, randomised, double-blind, placebo controlled trial has been designed to assess the efficacy, safety and tolerability of AB-2004 in children with autism.

The trial intends to include around 140 patients, who will be given either AB-2004 or placebo.

Its primary efficacy endpoint is the mean change in the Aberrant Behaviour Checklist Irritability subscale (ABC-I) from baseline to week eight for AB-2004, an investigational gut-targeted, molecular therapy.

Major secondary outcomes of the trial are the mean change in the Clinical Global Impression-Severity (CGI-S) from baseline to week eight, as well as the number of patients experiencing treatment related adverse events from baseline to week eight.

The trial is currently being carried out at various sites in the US, Australia and New Zealand.

It aims to conclude patient enrolment by the end of this year.

Axial Therapeutics CEO Stewart Campbell said: “We are pleased to announce that children ages 5 to 17 are now eligible to participate in our ongoing Phase 2b clinical trial of AB-2004 for the treatment of irritability associated with ASD, and we look forward to finalising enrolment later this year.

“This is significant because many children with autism struggle with irritability and anxiety.

“AB-2004 offers potential hope of a new therapeutic option for autism-related irritability that may improve the daily lives of children with autism, while also avoiding the side effects and risks of the currently available medications, providing a potential alternative for these children.”