Insmed Incorporated (NASDAQ:INSM), a people-first global biopharmaceutical company striving to deliver first- and best-in-class therapies to transform the lives of patients facing serious diseases, today announced that the U.S. Food and Drug Administration (FDA) has accepted the Company's Supplemental New Drug Application (sNDA) for review of ARIKAYCE® (amikacin liposome inhalation suspension) for the treatment of Mycobacterium avium complex (MAC) lung disease as part of a combination antibacterial drug regimen. In its communication to Insmed, the FDA granted Priority Review to the sNDA and set a target action date of January 28, 2027, under the Prescription Drug User Fee Act (PDUFA).

"The FDA's acceptance of this application marks a pivotal moment in our ambition to change the treatment paradigm for MAC lung disease," said Martina Flammer, M.D., MBA, Chief Medical Officer of Insmed. "MAC lung disease is progressive — the longer the infection persists, the greater the damage to lung tissue and the harder it becomes to treat. If full approval is granted, ARIKAYCE could reach patients earlier in their disease course, including those newly diagnosed or facing recurrent infections. We look forward to engaging with the FDA throughout the review process."

The FDA grants Priority Review to applications for medicines that, if approved, would provide a significant improvement in safety or effectiveness in the treatment of a serious condition.

ARIKAYCE received FDA accelerated approval in 2018 for refractory MAC lung disease and was the first product approved under the Limited Population Pathway for Antibacterial and Antifungal Drugs (LPAD) — a pathway enacted under the 21st Century Cures Act to advance the development of antibacterial therapies for serious or life-threatening infections in patients with unmet needs.

The sNDA for full approval is supported by results from the Phase 3b ENCORE study, the pivotal study conducted to fulfill the post-marketing requirement associated with ARIKAYCE's accelerated approval. ENCORE met its primary endpoint and multiplicity-controlled secondary culture conversion endpoints, with ARIKAYCE plus multidrug therapy demonstrating statistically significant improvements in respiratory symptoms and culture conversion in adults with MAC lung disease compared to multidrug therapy alone.

Insmed also plans to review the ENCORE data with the Pharmaceuticals and Medical Devices Agency (PMDA) in the fourth quarter of 2026 to support potential label expansion in Japan.