Zilganersen Fast Tracked for Patients With Alexander Disease

The Food and Drug Administration (FDA) has granted Fast Track designation to zilganersen for the treatment of Alexander disease, a rare type of leukodystrophy.

Alexander disease (AxD) is a genetic disorder that affects astrocyte cells. It is caused by a mutation in the glial fibrillary acidic protein (GFAP) gene. The resulting accumulation of altered GFAP protein in astrocytes leads to progressive neurologic deterioration. Zilganersen is an investigational antisense oligonucleotide designed to stop excess GFAP production.

The safety and efficacy of zilganersen is being evaluated in a double-blind, placebo-controlled phase 3 trial (ClinicalTrials.gov Identifier: NCT04849741) in patients aged 2 to 65 years with AxD. Study participants were randomly assigned 2:1 to receive zilganersen or placebo by intrathecal bolus injection once every 12 weeks through week 49.

The primary endpoint of the study is the percent change from baseline in the 10-meter walk test, an assessment of gait speed, at the end of the double-blind treatment period. According to Ionis Pharmaceuticals, topline data are expected in the second half of 2025.

“With no approved treatments available for people living with AxD, receiving this Fast Track designation for zilganersen reflects the seriousness of this ultra-rare disease and the significant unmet need for treatment in this patient population,” said Eugene Schneider, MD, executive vice president and chief clinical development officer at Ionis. “Zilganersen was designed to address the underlying cause of disease and help improve the functioning of people living with AxD. We look forward to a data readout next year and working closely with the FDA to potentially bring forward the first approved AxD treatment.”

The FDA’s Fast Track designation helps to accelerate the development and review of drugs for serious and life-threatening conditions where no treatment exists or where the investigational therapy is likely to provide an advantage over currently available treatments. Zilgenersen has also received the Agency’s Orphan Drug and Rare Pediatric Disease designations.

This article originally appeared on MPR