SAN FRANCISCO — Although inhaled human insulin has been approved by the FDA for use only in adults, it appears to be safe for use in children with type 1 diabetes, according to a poster presentation by Dr. Richard C. Ahrens at the international conference of the American Thoracic Society.
Combining the results of three studies comparing human insulin inhalation powder (Exubera) to subcutaneous insulin in 301 children aged 6–17 years, Dr. Ahrens, of the University of Iowa, and his colleagues concluded that the pulmonary safety profile of inhaled insulin in children is similar to that previously reported for adults.
The study was sponsored by Pfizer Inc., which manufactures Exubera. Two of the three investigators were Pfizer employees.
The children were initially followed for 24 weeks in the case of two of the trials, and for 12 weeks in the other trial. At the studies' conclusion, the children had the option of entering a long-term uncontrolled extension study in which all patients received inhaled insulin.
As in adults, the children using inhaled insulin showed small but consistent decreases in forced expiratory volume in 1 second (FEV1) and in diffusion capacity of the lung for carbon monoxide (DLCO). These decreases were evident at 12 and 24 weeks.
However, when the mean change from baseline in FEV1 was expressed as a percentage of that predicted, there were no significant changes over time, indicating that the children had normal lung growth while receiving inhaled-insulin therapy.
According to the investigators, pulmonary adverse events among the children were generally consistent with those seen in adults. Among the children taking inhaled insulin, 31.4% experienced cough, compared with 9.5% of the children taking subcutaneous insulin. The incidence of dyspnea was 3.3% among the children taking inhaled insulin and 0% among the children taking subcutaneous insulin.
The only serious adverse event was a case of pleural effusion, which occurred in one of the children taking inhaled insulin during the uncontrolled extension phase.