1. From Imperial College London and Royal Brompton and Harefield NHS Foundation Trust, London (J.C.D.), and the Manchester Adult Cystic Fibrosis Centre, Manchester (A.H.) — both in the United Kingdom; Vertex Pharmaceuticals (S.M.M., C.M.M., S.R., R.A.S., C.S., F.V.G., D.W., F.X., T.Y.) and Boston Children’s Hospital and Brigham and Women’s Hospital (A.U.) — all in Boston; Indiana University School of Medicine, Indianapolis (C.B.); Universitätsmedizin Berlin and Berlin Institute of Health, Berlin, and the...