id author title date pages extension mime words sentences flesch summary cache txt cord-298646-wurzy88k van der Merwe, René Challenge models to assess new therapies in chronic obstructive pulmonary disease 2012-09-13 .txt text/plain 4775 240 40 This review focuses on human challenge models with lipopolysaccharide endotoxin, ozone, and rhinovirus, in the early clinical development phases of novel therapeutic agents for the treatment and reduction of exacerbations in COPD. One of the main challenges in developing new therapeutic agents for the treatment or prevention of acute exacerbations of COPD is that their potential success cannot be entirely known until the investigational therapies enter relatively large Phase II studies, assessing clinical outcome over a 3-to 6-month period or longer. 20 In the first reported study of the inflammatory effects of low-level O 3 exposure (80 ppb O 3 for 6.6 hours) in healthy volunteers, 21 there were statistically significant increases in polymorphononuclear neutrophils, prostaglandin E 2 , lactate dehydrogenase, IL-6, α1-antitrypsin, and decreased phagocytosis via the complement receptor. The O 3 -challenge model potentially provides critical decision-making data in understanding whether new compounds have the desired biological effect in healthy volunteers and patients with COPD; hence it can de-risk decisions to move forwards into large Phase II safety and efficacy trials. ./cache/cord-298646-wurzy88k.txt ./txt/cord-298646-wurzy88k.txt