Inhaled muscarinic antagonists for respiratory diseases: a review of patents and current developments (2006 - 2010)

Abstract

Introduction: Because tiotropium has demonstrated clinical benefits as a long-term maintenance treatment for chronic obstructive pulmonary disease (COPD), the number of patent applications of new chemical entities with antimuscarinic activity has significantly increased, along with the number of compounds that have reached clinical development.

Areas covered: This review summarizes the current status of long-acting muscarinic antagonists (LAMA) in clinical development for COPD, and the associated patent literature since 2006, with a focus on new chemical entities.

Expert opinion: In recent years, companies have taken different approaches to obtain compounds with high potency, long duration of action and minimal systemic exposure. Several strategies for minimizing adverse effects due to systemic exposure have been identified (quaternization, higher rate of plasma hydrolysis and degradation, increased plasma protein binding). The beneficial effects beyond bronchodilation that may be provided in the treatment of COPD patients with a LAMA, and the advantages of combination therapies, such as LAMA + LABA and LAMA + corticosteroids, have also been taken into account in recent studies.