Effect of polymers for aerolization properties of mannitol-based microcomposites containing meloxicam

The aim of this study was to develop respirable microcomposites of meloxicam and adjuvants (different polymers and amino acid) for inhalation as drug delivery systems for local lung therapy. Meloxicam was transformed into microcomposites, i.e. crystals of drug embedded in mannitol and other adjuvants. We focused on the influence of polymers concentration on the physico-chemical properties of the microparticles. The objective was to optimize the aerodynamic parameters of the particles and to achieve the fast release of meloxicam. The size of the meloxicam particles suspended in aqueous mannitol solution containing different additives was reduced by high-pressure homogenization. Dry powders were produced from the microsuspensions by a co-spray-drying technique. Morphological, structural and in vitro dissolution studies were presented. The in vitro aerosol performance was tested by using the multistage Next Generation Impactor. It was found that polyvinyl alcohol and polyvinylpyrrolidone, promoted the presence of individual microcomposites by decreasing the aggregation tendency. L-leucine improved the fine particle fraction content of the samples. The co-spray-dried mannitol-based formulations containing the additives released 90% of the meloxicam by dissolution in 5 min. Aerodynamic assessment showed the fine particle fraction was >53% and the mass median aerodynamic diameter was <3.52 μm. This study indicated that meloxicam microcomposites prepared according to the described procedure are suitable for pulmonary local anti-inflammatory and antifibrotic therapy.