Objective: The aim of this study was to determine whether premeal pulmonary delivery of rapid-acting, dry-powder insulin (Exubera) plus Ultralente could provide glycemic control comparable to a conventional insulin regimen in type 1 diabetes.
Research design and methods: Three hundred thirty-five subjects were randomly assigned to receive either premeal inhaled insulin plus bedtime Ultralente or two to three injections of regular and NPH insulin for 24 weeks. The primary end point was a change in HbA(1c).
Results: Mean decreases in HbA(1c) values were comparable for inhaled (8.1-7.9%) and conventional groups (8.1-7.7%) (adjusted treatment group difference 0.16% [95% CI -0.01 to 0.32]). There were greater reductions for inhaled versus conventional regimen in fasting and postprandial plasma glucose (adjusted mean change differences -25.17 and -30.28 mg/dl, respectively [95% CI -43.39 to -6.95 and -54.58 to -5.97, respectively]). Hypoglycemia (events/subject month) was lower for the inhaled (8.6) versus the conventional (9.0) group (risk ratio, 0.96 [95% CI 0.93-0.99]). In subjects receiving inhaled insulin, increased insulin antibody levels were observed, but there were no associated clinical or laboratory changes. Adverse events were comparable between groups. Mild to moderate cough was more frequent in the inhaled insulin group (27 vs. 5%) but decreased during the treatment. Pulmonary function tests were not different between the groups except for a greater decrease in carbon monoxide diffusing capacity in the inhaled insulin group. Treatment satisfaction was greater in the inhaled than in the conventional group.
Conclusions: Inhaled insulin is effective, well tolerated, and well accepted in patients with type 1 diabetes and provides glycemic control comparable to that with a conventional insulin regimen.