Savara has received a Refusal to File (RTF) letter from the U.S. Food and Drug Administration regarding its Biologics License Application (BLA) for MOLBREEVI, an inhaled GM-CSF therapy for autoimmune pulmonary alveolar proteinosis (autoimmune PAP).
According to the company, the FDA found the application submitted in March 2025 was not sufficiently complete for substantive review, citing missing Chemistry, Manufacturing, and Controls (CMC) data.
The agency did not raise safety concerns or request further efficacy studies. Savara plans to request a Type A meeting with the FDA within 30 days to discuss the deficiencies and path forward. The company anticipates resubmitting the BLA in the fourth quarter of 2025 and says the requested CMC data are currently being generated.
In parallel, Savara continues to advance its supply chain strategy, including a technology transfer to a second-source drug substance manufacturer. The company has completed three upstream process performance qualification (PPQ) batches and is finalizing its downstream campaign and analytical comparability analysis.
“We are working to establish a redundant supply chain,” Savara CEO Matt Pauls said in statement. “We remain on track to complete the technology transfer with our second-source drug substance contract manufacturer in the fall.”
Autoimmune PAP is a rare lung disease characterized by the abnormal build-up of surfactant in the alveoli of the lungs. The RTF does not affect previously granted designations for MOLBREEVI in autoimmune PAP, including Fast Track, Breakthrough Therapy, and Orphan Drug designations from the FDA and the European Medicines Agency, as well as Innovation Passport and Promising Innovative Medicine designations from the U.K. Medicines and Healthcare products Regulatory Agency.
MOLBREEVI, which is delivered via an investigational eFlow Nebulizer System from PARI Pharma GmbH, remains an investigational therapy and has not been approved in any indication.