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.
Feb 18, 2026
Spruce Biosciences completed two Type B meetings with the FDA regarding tralesinidase alfa enzyme replacement therapy for Sanfilippo syndrome type B. The company now anticipates BLA submission in Q4 2026 to accommodate drug product process performance qualification requirements.
Feb 14, 2026
Ultragenyx Pharmaceutical announced positive long-term clinical data for UX111 gene therapy for Sanfilippo syndrome Type A, with up to 8.5 years of follow-up showing sustained biomarker reductions and functional improvements. The company resubmitted its BLA to the FDA in January 2026.
Feb 13, 2026
Ultragenyx reported Q4 2025 revenues of $207 million, up 25% year-over-year, while announcing a 10% workforce reduction and resubmission of its UX111 gene therapy application following positive long-term clinical data.
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.
