Neuren Pharmaceuticals (ASX:NEU) has commenced dosing in its "Koala" Phase 3 clinical trial.
The study marks the first-ever Phase 3 trial conducted for Phelan-McDermid syndrome, a genetic condition for which there are currently no approved treatment options.
The announcement follows the completion of a four-week screening period by the first participant, who has now moved into the 13-week, twice-daily dosing phase of the investigational drug, NNZ-2591.
The Koala trial is a randomized, double-blind, placebo-controlled study designed to evaluate the safety and efficacy of NNZ-2591 in approximately 160 children aged 3 to 12.
Given the urgent unmet medical need, the program has already secured Fast Track, Orphan Drug, and Rare Pediatric Disease designations from the US FDA.
Momentum is building rapidly; while two trial sites are currently active, Neuren expects to activate twenty additional sites across the United States throughout the first half of 2026.
Currently, 25 families have been referred for participation, with dozens more on waiting lists.
Neuren CEO Jon Pilcher expressed optimism regarding the study's trajectory and the high level of community engagement.
Neuren will also serve as the presenting sponsor for the 2026 PMS Foundation Family Conference in Colorado this July.