Inhaled human insulin findings varied

Two-year treatment with inhaled human insulin showed a small nonprogressive difference in forced expiratory volume in 1 second and comparable sustained HbA1c improvement when compared with subcutaneous insulin in adults with type 2 diabetes, according to the findings of a recent trial.

The treatment also reduced fasting plasma glucose levels and decreased weight gain when compared with subcutaneous insulin.

Researchers from Connecticut and other U.S. and international sites conducted a trial to examine the safety of inhaled human insulin (Exubera, Pfizer) in patients with type 2 diabetes who were nonsmokers (n=635). Patients were randomly assigned to prandial inhaled human insulin (n=319) or subcutaneous insulin plus basal insulin (n=316).

Adjusted treatment group differences in forced expiratory volume in 1 second annual rate of change were –0.007 1/year (90% CI, –0.021 to 0.006) for the entire treatment period, according to the researchers. The inhaled insulin group had an HbA1c reduction of 7.7% to 7.3% vs. the subcutaneous insulin group (7.8% to 7.3%).

The adjusted mean treatment difference for fasting plasma glucose was –12.4 mg/dL (90% CI, –19.7 to –5.0) and was greater in the inhaled human insulin group. Less weight gain was observed in the inhaled insulin group compared with the subcutaneous insulin group (–1.3 kg; 90% CI, –1.9 to –0.7), according to the researchers.

Diabetes Care. 2008;31:1723-1728.