1. From the Clinical Development and Medical Affairs, Boehringer Ingelheim GmbH, Ingelheim, Germany (W.G.E., A.C.); Departments of Medicinal Chemistry (N.H.), Drug Metabolism and Pharmacokinetics (J.S.), Pulmonary Research (W.W.), Drug Discovery Support (J.v.R.), Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany.