Regenxbio Shares Rally as CBER Head’s April Exit Eases RGX-121 CRL
Regenxbio’s RGX-121 gene therapy received an FDA Complete Response Letter over the validity of an external control cohort. The CBER director who signed the CRL is resigning in April, potentially smoothing the path for single-arm trial approvals and lifting investor sentiment in Regenxbio shares.
1. CRL Issued for RGX-121
The FDA issued a Complete Response Letter for Regenxbio’s RGX-121 gene therapy for Hunter syndrome after questioning the validity of the external control group used in the submission.
2. CBER Director Resignation
Dr. Vinay Prasad, who personally signed the CRL, is stepping down in April, ending a tenure marked by idiosyncratic decisions on rare disease reviews.
3. Analyst Perspective
Analyst Matt Phipps commented that Prasad’s departure could provide a tailwind for rare disease sponsors pursuing single-arm studies and external control arms in regulatory submissions.
4. Stock Rally
Following the news, Regenxbio shares climbed as investors anticipated fewer hurdles for RGX-121’s approval pathway.