- Male subjects aged 18-65.
- Documented clinical diagnosis of erectile dysfunction confirmed by an IIEF-EF Domain
score of less than or equal to 25. (If the subject scores greater than 25 on the
IIEF-EF Domain, screening procedures should be terminated.)
- Subjects who have been treated with more than 6 doses of sildenafil citrate or any
other phosphodiesterase type 5 (PDE-5) inhibitor such as vardenafil or tadalafil for
erectile dysfunction [Note: subjects should not have taken any PDE-5 inhibitors within
4 weeks prior to the date of screening].