Delivery of iloprost inhalation solution with the HaloLite, Prodose, and I-neb Adaptive Aerosol Delivery systems: an in vitro study.

BACKGROUND Iloprost (Ventavis) inhalation solution is approved in doses of 2.5 microg and 5.0 microg for treatment of pulmonary arterial hypertension (World Health Organization group I) in patients with New York Heart Association class III or IV symptoms, delivered with 2 Adaptive Aerosol Delivery (AAD) systems: Prodose and I-neb. The HaloLite device was the first-generation AAD system used in the clinical delivery of inhaled iloprost, and I-neb is the third-generation system. OBJECTIVE Study the in vitro performance of the HaloLite, Prodose, I-neb, in terms of mass median aerodynamic diameter (MMAD), fine-particle fraction (FPF, percent of aerosol droplets < 4.7 microm), and inhaled mass of iloprost. METHODS To analyze the MMAD and FPF, we collected the aerosol from each device with a cascade impactor. Because the devices are breath-actuated, airflow was regulated with flow-control valves to create inhalation and exhalation. To measure the inhaled mass of iloprost we used a breathing simulator with a filter system between the simulator and the device, and quantified the captured aerosol with iloprost-specific chromatography. RESULTS With the HaloLite, Prodose, and I-neb, respectively: the MMADs were 1.4 microm, 1.7 microm, and 2.1 microm; the FPFs were 91%, 82%, and 82%. The inhaled mass with the 2.5-microg dose ranged from 2.8 microg to 2.9 microg. The inhaled mass with the 5.0-microg dose ranged from 4.8 microg to 5.2 microg. CONCLUSION The HaloLite, Prodose, and I-neb AAD systems have comparable MMADs, FPFs, and inhaled mass with iloprost.