BERKELEY, CA (UroToday.com) - This review article examines the drug profile of vardenafil and its role in restoring erectile function; highlights a number of clinical trials on vardenafil in men with underlying cardiovascular and metabolic conditions, as well as in post-radical prostatectomy (RP) cases; and address the efficacy of vardenafil in comparison with other phosphodiesterase type 5 (PDE5) inhibitors.
Vardenafil is classified as a high-affinity PDE5 inhibitor, where lower biochemical potency, or dosage, is required to achieve the same clinical effect compared to other drugs, such as sildenafil.
The new vardenafil orodispersible tablet has been shown to have better bioavailability and a better safety profile than a film-coated vardenafil tablet. The most adverse effects of vardenafil are related to the systemic vasodilatation secondary to increased bioavailability of nitric oxide (NO). In general, vardenafil is well tolerated, with few treatment-related adverse events, and has a favorable safety profile in men with underlying cardiovascular and metabolic conditions. The overall PDE5 inhibitor’s drug interaction is minimal, unless PDE5 inhibitors are administered to patients on α-blockers and nitrate therapy. While there are numerous publications on the effectiveness of individual PDE5 inhibitors over a placebo group in the treatment of ED across different spectrum of medical conditions, there are very few comparative studies conducted among the 3 effective, commercially available PDE5 inhibitors. Nonetheless, published studies have shown that vardenafil has an equivalent efficacy to other PDE5 inhibitors and, more importantly, daily dosing of vardenafil 20 mg for 2 weeks has also been shown to salvage up to 18% of the so-called “vardenafil non-responders.”
Nonetheless, the current clinical trial on PDE5 inhibitors have many confounding factors, such as the dose concentration of the drug, variable inclusion criteria, duration of study, and exclusion of men intolerant of or poorly responsive to previous PDE5 inhibitors. Secondly, the design of head-to-head trials that compare PDE5 inhibitors may have had biased results in favor of 1 PDE5 inhibitor over another through research funding or restricted PDE5 inhibitor dosage. It is important to keep in mind that the erectile process is a complex interplay of neurohormonal and biopsychosocial factors where cardiovascular, endocrine, and neurologic conditions; local urinary tract diseases; drugs and alcohol problems; and psychosocial and partner issues, as well as social stressors, play an equally important part. Long-term surveillance and the management of ED patients remains paramount as ED is a multifactorial disease with underlying conditions, such as cardiovascular disease, diabetes mellitus, hypertension, and dyslipidemia, which are and will continue to progress as men get older.
Written by:
Eric Chung, MD, FACS1 as part of Beyond the Abstract on UroToday.com. This initiative offers a method of publishing for the professional urology community. Authors are given an opportunity to expand on the circumstances, limitations etc... of their research by referencing the published abstract.
1Department of Urology, Princess Alexandra Hospital, Brisbane QLD Australia
