News Related to RGX-121

FDA Grants Accelerated Approval to First Therapy for Neurological Effects of Hunter Syndrome

Jun 15, 2026

The FDA has granted accelerated approval to Denali Therapeutics' Avlayah (tividenofusp alfa-eknm), the first therapy targeting neurological symptoms of Hunter syndrome. The approval was based on a surrogate endpoint measuring heparan sulfate reduction in cerebrospinal fluid, with confirmatory study results required for full approval. The global Hunter syndrome treatment market is projected to reach $2.6 billion by 2033.

REGENXBIO Faces Class Action After FDA Clinical Holds on RGX-111 and RGX-121

Mar 20, 2026

A class action lawsuit was filed against REGENXBIO covering the period from February 9, 2022 to January 27, 2026, following FDA clinical holds on gene therapies RGX-111 and RGX-121 after a CNS tumor was discovered in a trial participant.

Unable to Synthesize Article Due to Inaccessible or Unrelated Source Content

Feb 17, 2026

The provided source articles lack sufficient accessible factual content for synthesis. One article is inaccessible, another covers unrelated stock performance topics, and the third concerns a different company entirely.

FDA Places Clinical Holds on Regenxbio Gene Therapies for Rare Metabolic Disorders

Jan 29, 2026

The FDA placed clinical holds on Regenxbio's RGX-111 and RGX-121 gene therapies following a tumor case in an MPS I patient. The company's stock fell nearly 18% on the news.