Ivacaftor improves lung disease in patients with advanced CF carrying CFTR mutations that confer residual function

Background Ivacaftor is an innovative treatment for CF. Ivacaftor monotherapy in a phase III trial for patients with F508del and a residual function (RF) mutation showed improvement in lung function. We evaluated the effectiveness and safety of ivacaftor in patients with severe CF carrying RF mutations. Methods Data were collected from Italian CF centers with patients enrolled in an ivacaftor compassionate use program. Data were collected 1 year before and 1 year after commencement of ivacaftor. Results Twenty-six patients received ivacaftor. The mean [standard deviation (SD)] percent predicted FEV1 significantly increased from 33.9% (8.3) before treatment to 44.0% (10.7) after 12 months of treatment (p Conclusions In patients with CFTR mutations that confer RF with severe lung disease, treatment with Ivacaftor is safe and results in a clinically significant improvement that was evident at 1 month and maintained at 12 months.