Abstract
Cystic fibrosis is a rare disease characterized by abnormalities in chloride and sodium transmembrane transportation due to various mutations in the cystic fibrosis transmembrane regulator (CFTR) gene, F508del being the most commonly found. Corrective therapies for this defect are currently under investigation and PDE5 inhibitors such as sildenafil or vardenafil were found to improve CFTR activity in vitro as well as in vivo. This paper evaluates a study investigating the effects of inhaled PDE5 inhibitors in an animal model of F508del cystic fibrosis, demonstrating that in this new formulation, such compounds are also able to improve CFTR function. Such results support the further development of this therapy for a systemic disease such as cystic fibrosis, provided several issues are addressed.