Clinical Proof-of-concept Study for the Combination BAY60-4552 / Vardenafil for the Treatment of Erectile Dysfunction Not Sufficiently Responsive to Standard Therapy With PDE5 Inhibitors

Inclusion criteria

• Open-label run-in phase (first four weeks):

• Written informed consent signed before any study-specific procedure
• History of ED (Erectile Dysfunction) for at least 6 months prior to screening, defined as "the inability to achieve and maintain an erection of the penis sufficient to complete satisfactory sexual intercourse"; the diagnosis of ED has to be confirmed by a physician
• Stable, heterosexual relationship for at least 6 months prior to screening
• Aged 18 to 64 years (inclusive) at the first screening examination
• History of previous use of at least 1 marketed PDE5 (Phosphodiesterase 5) inhibitor and insufficient therapeutic efficacy despite use of the highest approved dose
• Double-blind treatment phase (last four weeks):

• At least 4 attempts at sexual intercourse on 4 separate days during the open-label run-in phase with use of 20 mg vardenafil approximately 1 hour before attempting intercourse
• IIEF EF (International Index of Erectile Function - Erectile Function subscale) score <17
• At least 50% of attempts at sexual intercourse during the open-label run-in phase were unsuccessful

Exclusion criteria

• Contraindication to use of vardenafil
• History of prostatectomy due to prostate cancer, including nerve-sparing techniques.
• Concomitant use of adrenergic blockers
• History of spinal cord injury
• Resting hypotension, i.e. SBP (Systolic Blood Pressure) <100 mmHg at rest
• Moderate / severe hypertension, i.e. SBP >170 mmHg or DBP >110 mmHg at rest
• Symptomatic orthostatic hypotension with a decrease in SBP >20 mmHg or in DBP (Diastolic Blood Pressure) >10 mmHg subsequent to change from the supine to standing position