LANGHORNE, Pa. — Savara Inc. announced that the U.S. Food and Drug Administration (FDA) has issued a Refusal to File (RTF) letter for its Biologics License Application (BLA) for MOLBREEVI, a potential treatment for autoimmune pulmonary alveolar proteinosis (autoimmune PAP), a rare respiratory disease. The letter follows the company’s March 2025 submission of the BLA.
According to Savara, the FDA determined that the application was not sufficiently complete to allow for a substantive review and requested additional data related to Chemistry, Manufacturing, and Controls (CMC). The agency’s decision was not based on safety concerns, nor did it include a request for new efficacy studies.
Savara CEO Matt Pauls stated that the company plans to request a Type A meeting with the FDA within the next 30 days to clarify the agency’s requirements and align on a path forward. These meetings are typically scheduled within 30 days of the request. “The requested CMC data outlined in the RTF letter are currently being generated, and we look forward to meeting with the FDA to align on next steps,” Pauls said. “We are confident we can thoroughly address the Agency’s request and expect to resubmit our BLA in the fourth quarter of 2025.”
He added that the company remains confident in MOLBREEVI’s potential, citing clinical data showing improvement in pulmonary gas transfer and quality of life for patients with autoimmune PAP. In preparation for regulatory resubmission and future commercialization, Savara is working to establish a redundant supply chain and complete a technology transfer to a second-source drug substance manufacturer. The company has completed three upstream process performance qualification (PPQ) batches, is finishing its downstream PPQ campaign, and has begun analytical comparability assessments.
The RTF letter does not affect the regulatory designations previously granted to MOLBREEVI. The therapy continues to hold Fast Track and Breakthrough Therapy designations from the FDA, Orphan Drug designation from both the FDA and the European Medicines Agency (EMA), as well as the Innovation Passport and Promising Innovative Medicine designations from the UK’s Medicines and Healthcare Products Regulatory Agency (MHRA).
Savara remains committed to advancing MOLBREEVI as a treatment option for the underserved autoimmune PAP patient population.
