PSY58 - An Observational Study of Ivacaftor in Patients with Cystic Fibrosis and Selected Non-G551D Gating Mutations in UK, Italy and Netherlands: Healthcare Resource Utilization from the First Interim Analysis of the Vocal Study. - Castellani, C; Colombo, C; van der Ent, CK; Simmonds, NJ; Kinnman, N; Hassan, M; DeSouza, C; Kaviya, A (Value in Health, 2018)