The NDA and Priority Review designation were based on results from the pivotal study of zilganersen in children and adults living with AxD. In the study, zilganersen 50 mg demonstrated statistically significant and clinically meaningful stabilization on the primary endpoint of gait speed as assessed by the 10-Meter Walk Test (10MWT) compared to control at week 61 (least square mean difference 33.3%, p=0.0412) with favorable safety and tolerability. Results across key secondary and exploratory endpoints evaluating adaptive function, communication, GI symptoms, sleep and seizures also consistently favored zilganersen. New, additional data from the pivotal study will be presented at the 2026 American Academy of Neurology (AAN) annual meeting in Chicago, IL.

Priority Review designation is granted to marketing applications for medicines that, if approved, would provide a significant improvement in the safety or effectiveness of the treatment, prevention or diagnosis of a serious condition, with the expectation of the FDA taking action within six months, compared to 10 months under standard review. The FDA previously granted zilganersen Breakthrough Therapy, Orphan Drug and Rare Pediatric Disease designations.