Inhaled insulin: clinical results in type 2 diabetic patients

French type 2 diabetic patients are underinsulinised mainly because of fear of injections. Among all alternatives to the subcutaneous route, only the lung has a sufficient bioavailability of 10 % without addition of promoters . This is made possible by the large surface and thinness of the alveolo-ca pillary barrier, and only if insulin particles have an ideal size (2-3 micr ons). The Pfizer-Aventis-Inhale project utilises powder aerosolisation, whe ther the Novo-Aradigm project utilises liquid nebulization. In the former p roject, phase I studies have shown plasma kinetics similar to subcutaneous lispro, and intrasubject reproducibility non significantly different from r apid and lispro insulins. Phase 2 studies, performed on more than 200 insul in-treated and non insulin-treated subjects have shown an efficacy similar to subcutaneous insulin, with no difference in terms of side - effects (hyp oglycaemia, weight gain) and a satisfactory 1-year local tolerance, as eval uated by functional tests. Phase 3 studies, performed on 1400 subjects have just been completed and are not published yet. Though results are promisin g, some important questions remain to be clarified : long term tolerance, m iniaturisation of the inhaler, overcost, and long-term acceptability, espec ially in type 2 patients. It already appears that the major potential indic ations may be ''functional" (flexible) insulin therapy of type 1 diabetes a nd early insulinisation of type 2 patients with oral drugs failure.