Chiesi USA, Inc. – FDA CRL

The FDA issued a Complete Response Letter (CRL) to Chiesi USA for its Biologics License Application (BLA 761161) for PRX-102, initially received May 27, 2020. The agency determined that the application cannot be approved in its current form due to several key deficiencies. These include unresolved manufacturing facility issues identified during a review under the Federal Food, Drug, and Cosmetic Act, requiring satisfactory resolution. Additionally, PRX-102 no longer qualifies for accelerated approval because Fabrazyme, an existing therapy, received full approval, thus necessitating PRX-102 to demonstrate a therapeutic advantage. The FDA recommends an End-of-Review meeting to discuss the appropriate approval pathway, the status of the confirmatory trial, and the strategy for full approval by establishing a clear link between Gb3 reduction and clinical benefit. The proposed Prescribing Information also failed to conform to regulatory content and format requirements (21 CFR 201.56, 201.57) and must be revised and resubmitted in structured product labeling (SPL) format. The proprietary name "Elfabrio" needs resubmission. Finally, a comprehensive safety update, as per 21 CFR 314.50(d)(5)(vi)(b), detailing any significant changes or new findings, is required with the resubmission.