Fluticasone propionate/salmeterol combination in children with asthma: Key cardiac and overall safety results

This study studied the safety of fluticasone propionate/salmeterol combination (FSC) 100/50 HFA (2 inhalations of 50/25 mcg) twice daily, compared with fluticasone propionate (FP) 100 HFA (two inhalations of 50 mcg) twice daily, over a 12-week treatment period in subjects aged 4–11 years with persistent asthma. Of the 350 subjects randomized to receive double-blind treatment, 173 received FSC 100/50 HFA and 177 received FP 100 HFA. The two treatment groups were comparable in adverse events profiles, vital signs, asthma exacerbations, oropharyngeal examinations, clinical laboratory tests and urinary cortisol levels. The use of spacer did not meaningfully modify cortisol levels. The pre-specified analysis of 12-lead electrocardiograms (ECGs) identified abnormalities during screening as well as post-randomization in both study treatments, even though randomized subjects were without pre-existing cardiovascular disorders. An ad hoc analysis of the ECG data found no clinically relevant ECG abnormalities either prior to randomization or after randomization to study treatments. Thus, the ECG findings were false-positives related to details of the pre-specified analysis. This study highlights the importance of methodology when interpreting ECG data in a pediatric clinical trial. Overall, both FSC 100/50 HFA and FP 100 HFA were well-tolerated in children aged 4–11 years with persistent asthma.