FDA accepted Insmed’s application to expand ARIKAYCE use for MAC lung disease and granted priority review; the target decision date is Jan. 28, 2027. Its accelerated approval covers adults whose sputum cultures remain positive after at least six months of multidrug treatment.
Insmed seeks full approval and use alongside other antibiotics earlier in treatment, potentially including newly diagnosed patients and recurrent infections; the current indication is limited to adults with few or no alternatives. In ENCORE, 425 patients received ARIKAYCE or inhaled placebo with azithromycin and ethambutol for 12 months, followed by three months off treatment. At month 13, respiratory symptom scores improved 17.77 versus 14.66 points, a statistically significant 3.11-point difference; month-15 durable culture conversion was 76.2% versus 47.6%.
Priority review does not guarantee approval; the FDA’s final decision and label will determine who qualifies. In ENCORE, adverse events led 14.6% of ARIKAYCE recipients and 8.5% of placebo recipients to discontinue treatment. ARIKAYCE carries a boxed warning for respiratory reactions, including lung inflammation, coughing up blood, airway spasms and worsening underlying lung disease; some reactions have led to hospitalization.
