AN EVALUATION OF 2 AEROSOL DELIVERY SYSTEMS FOR RHDNASE

Increasingly, proteins are delivered to the respiratory tract as an ae rosol, and clinical efficacy is dependent on optimal delivery of the p rotein in an intact form, The object of this study was to compare the in vivo and in vitro results of two aerosol delivery systems for the a erosolization of recombinant human deoxyribonuclease I (rhDNase) in pa tients with cystic fibrosis (CF). Patients with CF who were to be init iated on rhDNase were randomized either to the Hudson nebulizer and Pu lmo-Aide compressor or to the Sidestream nebulizer driven by the CR50 air compressor, An in vitro study was performed in six sets of the two aerosol delivery systems, One hundred and seventy three patients were randomized in this open study, where rhDNase was administered for 7 d ays.Improvements in pulmonary function were observed in both groups fo llowing 1 week of therapy with rhDNase, Changes in the Sidestream/CR50 and Hudson/ Pulmo-Aide groups, respectively, were: 16 and 11% for for ced expiratory volume in one second (p=0.14); 12 and 10% for forced vi tal capacity (p=0.70); and 14 and 7% for forced expiratory flow at 25- 75% of expiration (FEF25-75) (p=0.18), A greater proportion of patient s in the Sidestream/CR50 group (58%) had a >10% response in FEF25-75 c ompared to the Hudson/Pulmo-Aide group (42%; p=0.03), The Sidestream n ebulizer had a faster nebulization rate (p<0.05), lower mass median di ameter for the aerosol mass produced (p<0.001), higher percentage of p articles in the respirable range (p<0.01) and greater respirable outpu t (p<0.005), compared to the Hudson nebulizer. The Sidestream/CR50 com bination is a quicker, more efficient system in vitro than the Hudson/ Pulmo-Aide combination, whereas the in vivo study only suggested a dif ference, Clinically, the two systems have similar efficacy.