Inhaled insulin found safe after two years

Exubera, the inhaled formulation of insulin in development by Pfizer,Aventis and Inhale Therapeutics, has been found to be safe after two years' administration whilst maintaining effective glycemic control, according to new data reported at a meeting of the American Thoracic Society in San Francisco. The finding is important as the development of side effects, particularly in the lung, has been widely perceived as the greatest threat to the product, which should be submitted for approval by the end of this year (Marketletter May 21).

One concern has been the fate of the 80%-plus of insulin delivered via the inhaler that does not make it into the blood, centering on the possibility that the excess may lead to local reactions in the lung. Aventis has reported that one patient out of 1,000 enrolled into clinical trials of the product developed pulmonary fibrosis, but this incidence does not differ from that seen in the general population. There was no evidence that patients' lung function was affected in the 140-patient study presented at the ATS meeting.