Sustainable Efficacy of Vardenafil OD Versus Vardenafil PRN in Erectile Dysfunction

Inclusion Criteria: * Males 18-64 years of age * Mild or mild to moderate ED (defined as \>15 and \<21 score points according to the Erectile Function Domain Score from IIEF as assessed at the randomisation visit) * History of at least one of the following conditions: Diabetes mellitus type 2, hypertension, peripheral arterial occlusive disease * Stable, heterosexual relationship for more than six months Exclusion Criteria: * Primary hypoactive sexual desire * History of myocardial infarction, stroke or life-threatening arrhythmia within prior 6 month * Nitrate therapy.