Future therapies for chronic obstructive pulmonary disease

No currently available treatments reduce the progression of chronic obstructive pulmonary disease (COPD) or suppress the inflammation in the small airways and lung parenchyma. However, several new treatments now in development for COPD are targeted at the inflammatory process. Antagonists of mediators, such as leukotriene B4, interleukin-8, tumour necrosis factor-α, transforming growth factor-β and inhibitors of oxidative and nitrative stress, are in clinical development. Broader-spectrum anti-inflammatory drugs now in development for COPD include phosphodiesterase-4 inhibitors and inhibitors of p38 mitogen-activated protein kinase, nuclear factor-κB and phosphoinositide-3 kinase-γ. There is also a search for elastase inhibitors to prevent the development of emphysema and for drugs that may even reverse the lung destruction. It will be important to identify suitable surrogate markers to predict clinical efficacy in COPD so that new anti-inflammatory approaches can be assessed. Effective delivery of drugs to the sites of disease in the peripheral lung is also an important consideration.