[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-capillary barrier, and only if insulin particles have an ideal size (2-3 microns). The Pfizer-Aventis-Inhale project utilises powder aerosolisation, whether the Novo-Aradigm project utilises liquid nebulization. In the former project, phase 1 studies have shown plasma kinetics similar to subcutaneous lispro, and intrasubject reproducibility non significantly different from rapid and lispro insulins. Phase 2 studies, performed on more than 200 insulin-treated and non insulin-treated subjects have shown an efficacy similar to subcutaneous insulin, with no difference in terms of side-effects (hypoglycaemia, weight gain) and a satisfactory 1-year local tolerance, as evaluated by functional tests. Phase 3 studies, performed on 1400 subjects have just been completed and are not published yet. Though results are promising, some important questions remain to be clarified: long term tolerance, miniaturisation of the inhaler, overcost, and long-term acceptability, especially in type 2 patients. It already appears that the major potential indications may be "functional" (flexible) insulin therapy of type 1 diabetes and early insulinisation of type 2 patients with oral drugs failure.