Dissolution of Orally Inhaled Drugs using DissolvIt^®: Influence of a Newly Designed Pre-Separator for Particle Collection

Beatriz Noriega^1,2, Maria Malmlöf^3,4, Eunice Costa¹, M. Luisa Corvo², Per Gerde^3,4, Filipa M. Maia¹

¹Hovione FarmaCiencia SA, Sete Casas, Loures, 2674-506, Portugal

²iMed.ULisboa, Faculdade de Farmácia, Universidade de Lisboa, Avenida Prof. Gama Pinto, Lisboa, 1649-003, Portugal

³Inhalation Sciences, Hälsovägen 7-9, 141 57, Huddinge, Sweden

⁴Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden

Summary

The goal of this work was to test the influence of a pre-separation step during particle collection for the dissolution profile determination of two commercial dry powder formulations: Flixotide Diskus (fluticasone propionate, FP) and Pulmicort Flexhaler (budesonide, BD). For this, the DissolvIt^® apparatus was used – an in vitro method for simulating the dissolution and absorption of inhaled dry powders that also mimics systemic pharmacokinetic data^[1]. Prior to dissolution, the powders were aerosolized and deposited onto coverslips using the PreciseInhale^® exposure system^[2], with and without a newly designed pre-separator (PS). The results show that the presence of the PS during powder collection has an influence on powder dispersion and the resulting dissolution profile, leading to faster dissolution. These results highlight the challenges in establishing biorelevant dissolution methods.