Results of phase I study of Baxter Healthcare Corporation's pulmonary insulin produced with Baxter's Promaxx microsphere technology and administered using a small, standard dry powder inhaler was absorbed systemically with no reported cough or shortness of breath. Baxter presented the phase I data at the Respiratory Drug Delivery Europe 2007 Conference in Paris, France.
The study demonstrates that the insulin powder can be effectively administered to the deep lung using an off-the-shelf dry powder inhaler designed for upper airway drug delivery. A total of 30 subjects participated in the randomized, two-way crossover study conducted in Germany. Each subject received in randomized fashion a single dose of 10 International Units of insulin through subcutaneous injection (SC) in one period, and 6.5 milligrams of the inhaled insulin microspheres, called recombinant human insulin inhalation powder (RHIIP) in the other period.
RHIIP is made using Baxter's proprietary Promaxx formulation technology. Unlike other dry powder formulations of insulin, RHIIP is 95 percent insulin and does not rely on the use of inactive ingredients to facilitate delivery to the deep lung.
"These encouraging results show the bioavailability of RHIIP compare favorably with that observed for many other inhaled insulin preparations, even though the standard type of inhaler used in this study was not optimized for delivery of insulin to the deep lung," said Dr Tim Heise, Profil Institut fur Stoffwechselforschung GmbH in Neuss, Germany, and principal investigator for the study. "RHIIP may have the potential to achieve even higher bioavailability through further improvements in the insulin delivery technique, and this will be the subject of further studies."