Denali Therapeutics announces FDA extension of tividenofusp BLA review timeline

Denali Therapeutics (DNLI) announced that the FDA has extended its review timeline of the biologics license application seeking accelerated approval of tividenofusp alfa for the treatment of mucopolysaccharidosis type II, also known as Hunter syndrome. The Prescription Drug User Fee Act target date has been extended from January 5, 2026, to April 5, 2026. The extension follows Denali’s submission of updated clinical pharmacology information in response to an information request from the FDA as part of the standard review process and is not related to efficacy, safety or biomarkers. The FDA classified the submission as a major amendment to the BLA, which, per FDA regulations, extends the review by three months. No additional data were requested by the FDA in the MA letter. Denali believes that the updated information submitted in the amendment does not affect the clinical pharmacology or benefit-risk conclusions of the BLA.