United Therapeutics Corp. – FDA CRL

The U.S. Food and Drug Administration (FDA) issued a Complete Response Letter (CRL) to United Therapeutics Corp. for its New Drug Application (NDA 214324) for treprostinil inhalation powder, stating it cannot be approved in its present form. The primary reason for the denial is a recent facility inspection that resulted in an Official Action Indicated (OAI) classification due to deficiencies in drug Current Good Manufacturing Practices (CGMP). Satisfactory resolution of these manufacturing issues is a prerequisite for approval.

Additional requirements include a comprehensive safety update, mandating detailed data from all clinical and nonclinical studies, combined tabulations of new and original safety data, a summary of worldwide experience, and English translations of foreign labeling. The FDA also reserved further comment on the proposed prescribing information, carton, and container labeling until other deficiencies are addressed, though updated content of labeling is required. The proposed proprietary name, Tyvaso DPI, was found acceptable but must be resubmitted with the corrected application.

United Therapeutics Corp. must address all identified deficiencies and resubmit the application within one year. The FDA also acknowledged a pending citizen petition regarding the NDA’s approvability, clarifying that the CRL reflects current agency thinking and is not a final decision on the petition's issues. The drug cannot be legally marketed until written approval is granted.