FDA places clinical hold on Regenxbio RGX-121 gene therapy for Hunter syndrome after spine MRI findings

• FDA imposed a clinical hold on RGX-121 for MPS II following asymptomatic spine MRI findings in five CAMPSIITE participants.
• Regenxbio does not expect to resubmit the RGX-121 BLA in the near term.
• Findings involved small nodules or cystic masses on spine MRI, seen about three to six years post-dose; investigators deemed them nonserious.
• Company is evaluating additional imaging and longer-term follow-up data, incorporating FDA feedback into next steps for RGX-121.

Disclaimer: This news brief was created by Public Technologies (PUBT) using generative artificial intelligence. While PUBT strives to provide accurate and timely information, this AI-generated content is for informational purposes only and should not be interpreted as financial, investment, or legal advice. Regenxbio Inc. published the original content used to generate this news brief via PR Newswire (Ref. ID: 202608240705PR_NEWS_USPR_____PH31991) on August 24, 2026, and is solely responsible for the information contained therein.