STUDY OF THE IMPACT OF DRYING PROCESSES ON POWDER PROPERTIES: A COMPARATIVE ANALYSIS OF SPRAY-DRYING TECHNOLOGY FROM SOLUTION AND SUSPENSION

Dry powder formulations for inhalation (DPI) are a promising pulmonary delivery system for dealing with localized respiratory conditions such as asthma and chronic obstructive pulmonary diseases. Advantages encompass drug stability and the absence of propellant gases, yet attention is directed toward enhancing DPI characteristics through particle engineering, mainly using the spray-drying method. Adjusting liquid composition and drying parameters aids in developing and optimizing DPI, enhancing aerodynamic performance, dispersibility, and flow properties.
This study aims to develop an inhalable powder containing two anti-asthmatic drugs,
ciclesonide and indacaterol, through the spray drying technique. The primary focus is to
compare the drying process of a solution versus a suspension on the resulting characteristics of the dry powders. To achieve this, suspensions are prepared by incorporating a surfactant agent (Tween® 80), while solubilization of APIs is facilitated using a cyclodextrin, specifically Crysmeb, selected based on a phase-solubility test.
Powders properties, lung deposition measured through fine particle fraction using a next-generation impactor, total recovery dose, and the homogeneity of powders post-spray drying process are studied and compared. The particle size of the obtained powders is less than 3µm, and the morphology in the form of deflated balls is favorable to enhance pulmonary deposition.
The findings appear to indicate an influence of the atomized liquid state on the results. Drying solution leads to increased pulmonary deposition (Fine Particle Fraction > 50%), improved powder homogeneity, and higher drug recovery doses (>99%), hinting at reduced API losses during drying.
These results will be valuable for anticipating the outcomes of the perspectives of this study, which focus on the drying of APIs encapsulated in liposomes.