Once-a-day dosing clinical study of udenafil for erectile dysfunction completed

Nov 19 2009

Dong-A Pharmaceutical Co., Ltd. and Dong-A PharmTech, Co. Ltd. announced today that it has completed a 240 patient once-a-day dosing clinical study of udenafil, its new long acting phosphodiesterase type 5 (PDE-5) inhibitor for erectile dysfunction (ED). The multi-center study conducted in Korea was a randomized, double-blind, placebo-controlled study, designed to investigate the efficacy and safety of udenafil in patients with ED. Following a 4-week non-drug baseline period, 240 men with ED of broad etiology and severity were randomized to one of four treatment groups: Placebo, udenafil 25 mg, udenafil 50 mg or udenafil 75 mg. Patients took one tablet a day for 12 weeks with evaluations every 4 weeks. The primary efficacy endpoint was the change in the standard International Index of Erectile Function (IIEF) Erectile Function Domain (EF) score from baseline to final visit. The secondary efficacy endpoints were the change from the baseline in the mean vaginal penetration success rates and mean intercourse completion rates calculated from the Sexual Encounter Profile (SEP) questions 2 and 3. In addition a sub-group analysis was conducted to determine efficacy in the patients that had lower urinary tract symptoms associated with benign prostatic hyperplasia in addition to erectile dysfunction.

The primary efficacy endpoint for the 50 mg and 75 mg doses were statistically significant compared to placebo. The mean vaginal penetration success rates at 12 weeks (final visit) were 98.7% (75mg) and 90.3% (50mg) and both dose levels were statistically significant compared to placebo (p<0.01). The change from baseline to final visit in the mean intercourse completion rates were 73.5% (75mg) and 51.4% (50mg) significantly (p<0.0001) higher compared to the 23.5% observed in the placebo group. Patients reporting improved erections after the 12-week course of therapy were 88% (75mg), 75% (50mg) and 69.5% (25mg) and significantly (p<0.0001) higher compared to 35.6% in the placebo group. Forty-four percent of the patients in the 75 mg group shifted to normal erectile function (EF domain scores > 25) after 12 weeks on drug compared to 13.6% in the placebo group.

Approximately 65% in this ED trial also had lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH) as assessed by the validated International Prostate Symptom Score (IPSS) questionnaire. Efficacy for the relief of lower urinary tract symptoms due to BPH was achieved consistently in a dose dependent manner.

All three active dose levels were well-tolerated; the most frequently reported Treatment-emergent adverse events were flushing and headache and were mostly mild to moderate in severity. No myalgia, back pain, leg pain or vision disturbances were reported and no serious adverse events related to the drug were reported.

"We are extremely pleased with the results of this trial which clearly demonstrated the excellent efficacy and safety of Zydena® when taken once a day for erectile dysfunction and potentially for other more chronic indications. The efficacy trend seen for the relief of LUTS was also a plus", commented Mr. Dong Hyun Park, President and CEO of Dong-A PharmTech. Mr. Park indicated that Dong-A PharmTech will initiate a development program for the treatment of LUTS associated with BPH and for pulmonary arterial hypertension in early 2010 in the USA.

Dr. Ridwan Shabsigh, a leading urology researcher in the USA commented, "the results indicate that Zydena® is efficacious for ED at once daily dose levels of 50 mg and 75 mg, and the analysis of the IPSS in the men having LUTS presents the potential for the use of Zydena® as a once a day treatment for LUTS associated with BPH".

Also commenting is Dr. Jae Seung Paick, a member of the Board of Chairman at Societe Internationale d'Urologie. Dr. Paick commented that "developing long-acting PDE-5 inhibitors for LUTS associated with BPH is gaining a strong momentum. Udenafil, given its favorable efficacy and side effect profile is an excellent candidate for this new exciting therapeutic option for this troublesome condition affecting many of my patients."

Zydena® is currently marketed in Korea and Russia.

SOURCE Dong-A PharmTech Co. Ltd.