June 22 - Regenxbio announced on Monday that the U.S. Food and Drug Administration has communicated an intent to reverse its earlier decision to decline approval of the company’s gene therapy for Hunter syndrome, Navsunli. The developer said the agency indicated that the existing clinical data could be sufficient to underpin an accelerated approval application. Shares of the Rockville, Maryland-based company rose roughly 10% in premarket trading on the news.
Background on the prior decision
In February, the FDA declined to approve Navsunli, citing uncertainty related to the trial design. Hunter syndrome is a rare inherited disorder in which the body cannot properly break down specific sugar molecules, impairing both physical and cognitive development.
Regulatory interactions and next steps
Regenxbio said it will request a formal meeting with the FDA in July and is targeting a resubmission in the third quarter. According to the company, the FDA told Regenxbio it would not require enrollment of additional patients or the initiation of new studies, including a previously requested placebo-controlled trial. The agency also indicated it would review the resubmission on an expedited timeline and that discussions regarding labeling are expected to begin shortly after the refiling.
Broader regulatory context
The company framed the development as part of a wider shift at the FDA in its approach to rare-disease therapies. Regenxbio noted this change followed an outreach effort by acting FDA Commissioner Kyle Diamantas, who met with advocacy groups earlier this month in what the company described as a signal the agency is seeking to mend relationships with the rare-disease sector.
Other recent industry regulatory moves
Regenxbio’s update came after several other companies reported regulatory course changes. Last week, uniQure said the FDA reversed its prior stance on that company’s gene therapy for Huntington’s disease, clearing the way for an accelerated approval filing after having earlier requested a new trial. Separately, Replimune said in May it intended to seek approval for its experimental skin cancer drug for a third time following an agreement reached with the U.S. regulator. News of these developments was reported earlier on Monday by The Wall Street Journal.
Market and procedural implications
The FDA’s indication that additional patient enrollment or fresh placebo-controlled studies would not be required removes two potential obstacles to a faster resubmission for Navsunli, in line with Regenxbio’s timetable for a July meeting and a third-quarter refiling. The regulator’s commitment to an expedited review and prompt labeling talks establishes a clearer procedural path forward, though the company will still need to complete the formal resubmission process.
Summary
Regenxbio reports the FDA has signaled it will reverse an earlier rejection of Navsunli and that the data on hand could support an accelerated approval application. The company is arranging a meeting with the agency in July, aims to resubmit in Q3, and said the FDA does not plan to require new patient enrollment or additional placebo-controlled trials. The FDA has agreed to an expedited review of the resubmission and to begin labeling discussions soon after refiling.