A once-daily dosing regimen with udenafil (Zydena), an experimental phosphodiesterase type 5 inhibitor, can significantly improve erectile function in men with erectile dysfunction (ED), according to a new Korean study published online in European Urology.
Chen Zhau, MD, and his colleagues conducted a multicenter, randomized, double-blind, placebo-controlled 12-week clinical trial involving 237 men with ED. Udenafil recipients received 25, 50, or 75 mg doses of the drug once daily. Each participant completed the International Index of Erectile Function (IIEF), the Sexual Encounter Profile (SEP) diary, and the Global Assessment Questionnaire (GAQ).
Men who received 50 or 75 mg of udenafil had significantly improved IIEF-EFD scores. Significant improvements were also demonstrated based on some of the questions in the SEP diary and the GAQ. Overall, the changes from baseline in each domain of the IIEF in the udenafil 50 and 75 mg groups showed significant improvement with the exception of orgasmic function.
Udenafil is rapidly absorbed, reaching peak plasma concentrations at 0.8- 1.3 hours and then declining mono-exponentially with a terminal half-life between 7.3 and 1.21 hours. The researchers found this agent may be a safe and effective alternative for men who do not wish to take on-demand drugs such as sildenafil and vardenafil, which can interfere with spontaneity.
Adverse events (AEs) associated with udenafil were similar to those commonly observed in other studies of PDE-5 inhibitors. Flushing and headaches were the most commonly reported AEs. However, udenafil did not induce myalgias or abnormalities in color vision, which can occur in patients taking tadalafil and sildenafil. The researchers observed no clinically significant change in laboratory tests, electrocardiograms, or blood pressure in the udenafil groups.