The orally active phosphodiesterase IV inhibitor roflumilast is effective in the treatment of asthma and chronic obstructive pulmonary disease (COPD), according to data from clinical studies presented at the 12th Annual Meeting of the European Respiratory Society [Stockholm, Sweden; September 2002]. Roflumilast demonstrated dose-dependent activity in the treatment of asthma, and had efficacy comparable to beclomethasone. A study involving patients with COPD also demonstrated favourable efficacy and tolerability.