HealthDay News— Adding the inhaled dry powder mannitol to standard therapy for cystic fibrosis produces sustained improvement in lung function for up to 52 weeks, according to a study published online Dec. 16 in the American Journal of Respiratory and Critical Care Medicine.
Moira L. Aitken, MD, from the University of Washington Medical Center in Seattle, and colleagues conducted a double-blinded, randomized, controlled study in which 192 patients received 400mg twice daily inhaled mannitol (treatment group) and 126 patients received 50mg twice daily inhaled mannitol (control group) for 26 weeks, followed by an additional 26 weeks of open-label active treatment. A 50mg dose was chosen as the control because it was thought to be clinically ineffective based on an earlier dose-escalation study.
Between the treatment and control groups, the researchers found non-significant differences in mean absolute forced expiratory volume in one second (FEV1) (P=0.059) but significant relative change from baseline FEV1 (P=0.029). Improvements in FEV1 were maintained in the treatment group throughout the study. Rates of adverse effects were similar between the two groups, and there were no qualitative changes in sputum microbiology in either group.
“In this Phase 3 study, 12 month use of inhaled mannitol 400mg twice daily resulted in sustained improvement in lung function relative to control, as measured by FEV1 and forced vital capacity and reduced exacerbations, and had a good safety profile with excellent treatment compliance over 26 weeks of treatment,” the authors write.
The study was supported by Pharmaxis Limited, the developer of the dry powder form of mannitol. Pharmaxis participated in the study design, data collection, data analysis, data interpretation, and writing of the study report.