Recent Advancements and Applications of Inhalable Microparticles Based Drug Delivery Systems in Respiratory Disorders

Abstract

Lower respiratory infections are the third leading cause of death, as stated by the world health organization. The pulmonary route requires reduced dose, exhibits immediate drug release, reduced first-pass hepatic metabolism and adverse effects, and systemic drug release. Therefore, an overview of recent advancements in inhalable microparticles reported in publications and patents published in the last few years has been summarized. Recent innovations in inhaler technology and major challenges in pulmonary drug delivery have been discussed briefly. The analysis was collected through comprehensive literature searches from databases such as PubMed, Google Scholar, and ScienceDirect. The recent patents on inhalable microparticles have been compiled through the PATENTSCOPE database via WIPO website. The keywords used in the search strategy were ‘inhalable microparticles’, ‘polymeric microparticles’, ‘large porous microparticles’, ‘solid lipid microparticles’, ‘cyclodextrin complex microparticles’, ‘respiratory disorders’, ‘patent, ‘inhaler technology’, ‘drug deposition’, ‘pharmacokinetic processes’ and ‘pulmonary drug delivery’ in various combinations. A survey of literature revealed that 44 publications and 14 patents, and 9 recent innovations in inhaler technology had been reported regarding inhalable microparticles in respiratory disorders. This review briefly recapitulates the pharmacokinetic processes involved in the pulmonary drug delivery route, mechanisms of drug deposition in the respiratory tract, types, and production methodology of inhalable microparticles.