Regenxbio completes pre-BLA meeting with FDA for RGX-121 accelerated approval

Regenxbio completed a successful Pre-Biologics License Application meeting for RGX-121 for the treatment Mucopolysaccharidosis Type II, where it finalized details of its BLA with the FDA. The FDA continues to be aligned with Regenxbio’s plan to use cerebrospinal fluid levels of heparan sulfate D2S6, a key biomarker of brain disease activity, as a surrogate endpoint reasonably likely to predict clinical benefit to support accelerated approval of RGX-121. Additionally, Regenxbio and the FDA discussed manufacturing, non-clinical, device delivery system and other critical elements of the BLA, including a confirmatory study designed to verify and describe the predicted clinical benefit. Regenxbio expects to initiate submission of a rolling BLA in Q3 2024. Regenxbio expects an FDA inspection of its Manufacturing Innovation Center in the first half of 2025. A confirmatory study of RGX-121 is expected to initiate enrollment in the second half of 2025, prior to potential FDA approval. Based on an expected priority review, potential approval of the planned BLA could result in receipt of a Rare Pediatric Disease Priority Review Voucher in 2025.