West Haven, Conn. (April 7, 2001) -- Results from the first large-scale patient trial of vardenafil, Bayer's investigational phosphodiesterase-5 (PDE-5) inhibitor, showed that vardenafil not only improved erections in up to 80 percent of men, but also increased their ability to complete sexual intercourse with ejaculation. The results of three separate sub-analyses were presented today at the XVI annual European Association of Urology (EAU) meeting in Geneva, Switzerland.

"Vardenafil improved erectile function in these men, regardless of their age, cause, or severity of their problem. This improvement occurred even at the lowest dose of 5 mg," said Dr. Irwin Goldstein, Boston University School of Medicine, a co-author of the analyses, and a member of the international Vardenafil Study Group. "There was another important finding as well," continued Goldstein. "In the overall study, vardenafil not only helped most men achieve erections, they also were able to sustain their erections and successfully complete intercourse."

The analyses involved 580 patients, ages 21--70 years, in stable heterosexual relationships, from 39 treatment centers in the U.S., Belgium, France, Germany, the Netherlands, Poland, and South Africa. The patients had experienced difficulty with erectile function of organic, psychogenic, or mixed etiology for an average of 2.8 years. They were randomized into four groups and received vardenafil in 5 mg, 10 mg, or 20 mg doses, or placebo on demand, but not more than once a day.

In the sub-analyses, effects of vardenafil were evaluated by patients' responses to two key questions of the International Index of Erectile Function (IIEF) questionnaire: the ability to penetrate (question 3/Q3) and the ability to maintain an erection during intercourse
(question 4/Q4). The scoring was based on a five-point scale, with one being the most severe.

Ability to Penetrate Improved Regardless of Severity

Those with a baseline Q3 score of 1.0 (i.e., with very little ability to penetrate) increased their score to a mean of 1.8 with placebo and to 3.0, 3.1, and 3.7 with 5 mg, 10 mg, and 20 mg of vardenafil, respectively. Those with a starting score of 4.0 on Q3 deteriorated to a mean score of 3.4 with placebo, but increased to a mean of 4.4, 4.7, or 4.4 for the same increasing doses of vardenafil.

Ability to Complete Intercourse Improved Regardless of Severity

For Q4, the results were similar. Those with a score of 1.0 (i.e., with very little ability to maintain an erection and complete intercourse) increased their score to a mean of 2.0 with placebo and to scores of 3.3, 3.1, and 3.5 with increasing doses of vardenafil. Those with a relatively mild degree of severity starting with a score of 4.0 had a decreased mean of 3.6 on placebo, but reached a score of 4.0, 4.3, or 4.7 with increasing doses of vardenafil.

Improved Response Regardless of Underlying Cause

Having an organic or psychogenic etiology of erectile dysfunction did not influence the efficacy of vardenafil. The mean changes in score of Q3 for organic and psychogenic respectively were: 0.3 and 0.3 for placebo, 1.2 and 1.4 for 5 mg, 1.5 and 1.1 for 10 mg, and 1.3 and 1.4 for 20 mg doses of vardenafil. Similar responses were seen for Q4.

Age Did Not Influence Response to Vardenafil

The patients were divided into four age groups: younger than 45, 45--55, 55--65, and older than age 65. For Q4 the mean increases in score for placebo-treated patients ranged between 0.2 and 0.8 in each age group. For vardenafil-treated patients, a statistically significant treatment effect was found for all doses with mean increases ranging between 0.8 and 1.9, but no one age group had a superior response to vardenafil.

Safety Profile

"Our study also demonstrated that vardenafil was well tolerated, with few patients reporting any adverse events," Dr. Goldstein reported. The most frequent adverse events, whether related to the drug or not, were headache (7--15 percent), flushing (10--11 percent), rhinitis (3--7 percent), and dyspepsia (1--7 percent). The events were generally mild in intensity and related to dosage.

Important Preclinical Findings Presented to EAU

In preclinical studies, the pro-erectile activity of vardenafil was greater than sildenafil at equivalent dosing1. In a separate study, vardenafil was found to be highly selective at targeting the PDE-5 enzyme, which is believed to be responsible for inducing erections2. Vardenafil is now being evaluated in Phase III trials to better understand if these characteristics will translate into clinical benefits for patients. Results are expected for publication later this year, with completion of the Food and Drug Administration (FDA) review in late 2002. Current estimates suggest that more than half of all men in the U.S. over age 40 experience some difficulty with erectile function3.

Bayer Committed to Men's Health

Bayer Corporation is helping men manage their health through a range of therapies. Bayer has already established itself as a credible force in men's health with Cipro(R) (ciprofloxacin HCl). Other men's health products include One-A-Day(R) Men's High Potency Multivitamin/Multimineral Supplement, and One-A-Day(R) Prostate Health. In addition, Bayer is in the process of launching a recently approved once-yearly implant for the palliative treatment of advanced prostate cancer.

Although best known for its flagship product, Bayer Aspirin, Bayer Corporation produces a broad range of health care, life sciences, and chemical products that help diagnose and treat diseases, purify water, preserve local landmarks, protect crops, advance automobile safety and durability, and improve people's lives.

Headquartered in Pittsburgh, Bayer Corporation had sales of $10.1 billion in 2000, and is one of Fortune magazine's Most Admired Companies. The company employs 23,200 people. It is a member of the worldwide Bayer Group, a $29 billion international life sciences, polymers, and specialty chemicals group based in Leverkusen, Germany. The Bayer Group (BAYG.DE) stock is a component of the DAX, and Bayer plans to list its stock on the New York Stock Exchange Sept. 26, 2001.

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References
1. Giuliano F., Allard J., Bernabe J., Alexandre L., Bischoff E. "Comparative Study of the Facilitator Proerectile Effect of Vardenafil and Sildenafil in Anesthetized Rats." (Poster presented at EAU, 2001)
2. Tejada I.S., Bischoff E., Niewohner U., Haning H., Angulo J., Cuevas P., Fernandez A., Gabancho S., Pomerol J., Piugvert A., Ruiz-Castane E., Rive N. "Potentiation of the NO mediated Relaxation of Human Trabecular Penile Smooth Muscle by the PDE-V Inhibitor, Vardenafil." (Poster presented at EAU, 2001)
3. Feldman H., Goldstein I., Hatzichristou D., Krane R., and McKinlay J. Impotence and its
medical and psychosocial correlates: Results of the Massachusetts Male Aging Study.

Journal of Urology 1994;151:54--61

---Fleishman-Hillard

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