Mucus and Cell-Penetrating Nanoparticles Embedded in Nano-into-Micro Formulations for Pulmonary Delivery of Ivacaftor in Patients with Cystic Fibrosis.

Here, mucus-penetrating nanoparticles (NPs) for pulmonary administration of ivacaftor in patients with cystic fibrosis (CF) were produced with the dual aim of enhancing ivacaftor delivery to the airway epithelial cells, by rapid diffusion through the mucus barrier, and at the same time, promoting ivacaftor lung cellular uptake. Pegylated and Tat-decorated fluorescent nanoparticles (FNPs) were produced by nanoprecipitation, starting from two synthetic copolymers, and showed nanometric sizes (∼70 nm), a slightly negative ζ potential, and high cytocompatibility toward human bronchial epithelium cells. After having showed the significant presence of poly(ethylene glycol) chains and Tat protein onto the FNP surface, the FNP mucus-penetrating ability, ivacaftor release profile, and lung cellular uptake were studied in the presence of CF-artificial mucus as a function of the FNP surface chemical composition. Moreover, microparticle-based pulmonary drug-delivery systems composed of mucus-penetrating FNPs loaded with ivacaftor and mannitol were prepared by using the nano-into-micro strategy and realized by spray-drying, thereby providing optimal preservation and stabilization of FNP technological and fluorescence properties.