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Head to Head Study Proves Non-Inferiority of Vardenafil HCI in Comparison to Sildenafil for Treatment of Erectile Dysfunction

Levitra achieved nominal statistical superiority to Viagra for several frequently used efficacy measures ~

MONTREAL, CANADA -- September 19, 2006 -- Results of a new medical study, launched today at the Congress of International Society of Sexual Medicine (ISSM) in Cairo, Egypt, and published in the Journal of Sexual Medicine, show that men with erectile dysfunction (ED) and risk factors for cardiovascular disease expressed a treatment preference - 53% preferred Levitra® (vardenafil) compared to 47% who preferred Viagra® (sildenafil).

This study demonstrated non-inferiority of Levitra to Viagra for overall preference and achieved statistical superiority to Viagra for several frequently used efficacy measures - meaning that Levitra is at least as good as Viagra, while SEP 2 and 3* efficacy shows a superior effect for Levitra.

Comparative clinical trials can be difficult to design in an unbiased way; however, the CONFIRMED [COmparing vardeNafil and sildenaFil In the tReatment of Men with Erectile Dysfunction (ED)] study has been consciously designed to be truly unbiased towards either treatment. The CONFIRMED Study is a randomized, double-blind, pooled crossover study that compared patient preference and satisfaction with the two treatments in men with ED and diabetes, hypertension and/or hyperlipidemia.

"The CONFIRMED study represents an important step forward in our understanding of the clinical differences between PDE-5 inhibitors, confirming the efficacy of Levitra for men with erectile dysfunction," explains Irwin Goldstein, study co-author and editor in chief of the Journal of Sexual Medicine.

A total of 1,057 men were recruited for the study. Of those men, 38.9% expressed an overall preference for Levitra over Viagra (34.5%) and 26.6% of patients had no treatment preference. As this difference was not statistically significant, this result confirms the non-inferiority of Levitra. Further, Levitra achieved nominal statistical superiority to Viagra for several frequently used efficacy measures: Levitra achieved better response for men responding to the Sexual Encounter Profile questions two and three; 83.9% of men taking Levitra responded positively to SEP2 (p=0.0389) compared with 82.2% for Viagra; and 74% of men reported a positive response to Levitra for the question SEP3 (p=0.0038) against 72% for Viagra.

The CONFIRMED study minimized bias seen in other comparative trials by consciously creating an unbiased methodology that included 13 separate criteria. Trial results that are more likely to be accepted by the medical community are usually randomized (patients are chosen randomly to be given one treatment or the other), double-blinded (neither the researcher nor patient know which treatment the patient is taking until the end of the study), and a cross-over designed (each patient tries one treatment and then the other). Additionally, this trial used equivalent drug doses, had a randomized treatment sequence, used a neutral consent form, assessed preference after each treatment period and, importantly, did not eliminate previous non-responders or only include naïve patients (patients who had never used an ED treatment before).

"I am pleased with what the results of the CONFIRMED study show. It is currently the best well-designed preference data that we have when looking at patients with ED who have or who are at risk for diabetes and other conditions," said Dr François Bénard, Associate Professor of Urology, Program Director of Urology, University of Montreal, Urologist, Hôpital Saint-Luc, Montréal. "As a physician who treats men with ED, I believe it's important that men have options, to find what's right for them."

About the CONFIRMED Study
The CONFIRMED Study (COmparing vardeNafil and Viagra In the tReatment of Men with Erectile Dysfunction) is a randomized, double-blind, pooled crossover study. This is a study of 1057 men aged ÿ18 years with ED for >6 months according to NIH criteria; and risk factors for cardiovascular disease (diabetes mellitus, hypertension and/or hyperlipidemia). Another requirement was a stable, heterosexual relationship for more than the last six months.

Patients underwent two four-week treatment periods, study medication being either Levitra 20 mg or Viagra 100 mg. Preference questions were asked after completion of each treatment period. As well as overall preference, 11 other preference questions were asked. Additionally, efficacy questions were asked including: the erectile function (EF) domain score of the International Index of Erectile Function (IIEF); Sexual Encounter Profile (SEP) diary questions two and three; Global Assessment Questions (GAQ), and Treatment Satisfaction Scale (TSS).

About Erectile Dysfunction
Erectile dysfunction (ED) is defined as the consistent or recurrent inability of a man to attain and/or maintain a penile erection sufficient for sexual performance.1 It is estimated that some degree of ED affects about half of all men over the age of 40 and that worldwide an estimated 152 million men suffer from ED2, including three to four million men in Canada.3 The number of men with ED is expected to more than double to 322 million men worldwide by 2025.4 Despite the high prevalence of sexual dysfunction, experts estimate that only 15-20% of men with ED are currently treated.5

REFERENCES:
1. Jardin A, Wagner G, Khory S et al. Recommendations of the 1st International Consultation on Erectile Dysfunction. Co-sponsored by the World Health Organisation (WHO), International Consultation on Urological Diseases (ICUD) and Societé Internationale D'Urologie (SIU). p.713.
2. Rosen RC, Fisher W, Eardley I, Neiderberger C, Nada A, Sand M: The Multinational Men's Attitudes to Life Events and Sexuality (MALES) Study I, Prevalence of Erectile Dysfunction and Related Health Concerns in the General Population. Cur Med Res Op.
3. Barkin J, Carrier S, Gajewski J, Brock G. Erectile function and male sexual satisfaction: A national survey. J Sex Reprod Med 2003; 3:10B-14B.
4. Aytac IA, McKinlay JB, Krane RJ: The likely world increase in erectile dysfunction between 1995 and 2065 and some possible policy consequences. BJU International 1999; 84:50-56.
5. Southgate J: New rivals to Viagra expand the market. Scrip World Pharmaceutical News, 2002.

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