Cilomilast
Cilomilast (Ariflo, SB-207,499) is a drug which was developed for the treatment of respiratory disorders such as asthma and Chronic Obstructive Pulmonary Disease (COPD). It is orally active and acts as a selective Phosphodiesterase-4 inhibitor. Following four clinical trials, the drug proved to be effective in treating COPD, however it has never been marketed due to a poor side effect profile.