07:40 AM EDT, 03/23/2026 (MT Newswires) -- Ionis Pharmaceuticals ( IONS ) said Monday that the US Food and Drug Administration granted priority review designation for its new drug application for zilganersen as a potential treatment for Alexander disease.

The company said the priority review was based on the results of a pivotal study of zilganersen in children and adults living with Alexander disease, where the product candidate demonstrated statistically significant stabilization in the primary endpoint of gait speed assessed by the 10-Meter Walk Test.

Ionis said the FDA has designated a target action date of Sept. 22 for the application.