Aerodynamic properties and in silico deposition of meloxicam potassium incorporated in a carrier-free DPI pulmonary system.

Dry powder inhalers (DPIs) have been among the fastest developing inhaler forms in the past decades. Researches are focusing on the formulation of carrier-free powders to obtain a higher deep-lung deposition and hereby to increase the effectiveness of the medicine. The aim of our study was to prepare a carrier-free dry powder formulation of meloxicam potassium (MP), a novel salt form of meloxicam, using a one-step co-spray drying technology. Different types of excipients were used to modify the crystal structure and to increase aerosolization efficacy. Micrometric properties and the crystal structure were characterized. Aerodynamic properties were tested in vitro using an Andersen Cascade Impactor. A new in silico Stochastic Lung Model was also applied to quantify the amount of particles deposited at the target area. The results have shown that formulated DPI samples are fulfilling the requirements of effective pulmonary drug delivery: they include spherical particles with low density and 1-5μm size distribution. The in silico deposition results correspond with the in vitro measurements and demonstrate that the engineered microcomposites reach a high lung deposition. MP offers a novel opportunity for a well-controlled DPI formulation prepared by a solution-based co-spray drying method.