Pooled analysis of two large randomised phase III inhaled mannitol studies in cystic fibrosis

Background: To evaluate safety and efficacy of inhaled mannitol treatment in subgroups of a large global CF population. Methods: Data were pooled from two multicentre, double-blind, randomised, controlled, parallel group phase III studies in which 600 patients inhaled either mannitol (400 mg) or control (mannitol 50 mg) twice a day for 26 weeks. Results: Both the mean absolute change in FEV1 (mL) and relative change in FEV1 by % predicted from baseline for mannitol (400 mg) versus control were statistically significant (73.42 mL, 3.56%, both pb0.001). Increases in FEV1 were observed irrespective of rhDNase use. Significant improvements in FEV1 occurred in adults but not children (6–11) or adolescents (aged 12–17). Pulmonary exacerbation incidence was reduced by 29% (p=0.039) in the mannitol (400 mg) group.