Dong-A Pharmaceutical Co., Ltd. Release: Zydena, A New Erectile Dysfunction (ED) Drug, Receives Marketing Approval In Korea

SEOUL, Korea, Nov. 30 /PRNewswire/ -- Dong-A Pharmaceutical Co., Ltd., announced today that they received marketing approval from the Korean Food and Drug Administration (KFDA) for udenafil, their new phosphodiesterase type 5 (PDE5) inhibitor for erectile dysfunction (ED). Udenafil will be marketed in Korea under the brand name Zydena in 100 mg and 200 mg tablet strengths.

Dong-A Pharmaceutical Co., Ltd.'s new oral tablet for ED will compete with Viagra (sildenafil, Pfizer), Cialis (tadalafil, Lilly/ICOS), and Levitra (vardenafil, Bayer/GSK) for a share of the estimated 100 million dollar ED market in Korea. Various Phase 2 and 3 clinical studies have shown that udenafil produced highly significant improvement in erectile function after 12 weeks of drug therapy with up to a 92% vaginal penetration success rate compared to 53% for the placebo group and up to 76% intercourse completion rate compared to 15% for the placebo group.

Additionally, 48% of the patients in Phase 3 clinical studies at the high dose level returned to normal function after 12 weeks on drug compared to only 4% on placebo. The overall patient satisfaction as measured by the standard global assessment question (GAQ) was up to 89% in the high dose treatment group compared to 26% in the placebo group. The most frequently noted side effects were mild to moderate facial flushing and headache which are expected for this class of drug.

Previous Phase 1 studies have shown that udenafil has a unique pharmacokinetic profile (Tmax of 1.0-1.5 hours and a half-life of 11-13 hours) suggesting that the drug could have a relatively rapid onset and sufficiently long duration to make it effective for up to 24 hours. In a separate study involving more than 100 subjects to confirm udenafil's long duration, the drug was shown to be efficacious in 55% of the ED patients after 8 to 12 hours. Prior studies have also demonstrated a selectivity profile for udenafil that is similar to sildenafil but unlike tadalafil, it does not significantly inhibit the PDE11 isozyme and thus is not expected to produce significant myalgia. No myalgia, back pain, or leg pain was observed in the Phase 3 studies for udenafil.

Dr. Shin-Ho KANG, the Chairman of Dong-A Pharmaceutical and Chairman of the Federation of Korean Industries which recently hosted APEC's CEO conference in Busan, Korea, stated that "We are extremely pleased to see the marketing approval of Zydena in Korea. This is an important milestone in our plan to develop udenafil globally, not only for erectile dysfunction but also for numerous other indications."

Dong-A PharmTech, Co., Ltd, an affiliate of Dong-A Pharmaceutical Co. Ltd. filed an IND with the US FDA in February 2005 and is conducting a Phase 2b clinical study in the USA involving 300 ED patients. Mr. Dong Hyun PARK, President & CEO of Dong-A PharmTech, stated, "We congratulate Dong-A Pharmaceutical Co., Ltd. for this approval and we look forward to working closely with our sister company in further development for this unique compound." Dong-A PharmTech Co., Ltd.'s clinical development program for Zydena is ongoing in the USA and is expected to move into Phase 3 clinicals in 2006.

About Dong-A Pharmaceutical Co., Ltd.

Dong-A Pharmaceutical Co., Ltd., founded in 1932, is the largest drug company in Korea. It is listed on the Korean stock exchange.

About Dong-A PharmTech Co., Ltd.

Dong-A PharmTech Co., Ltd. is an affiliate of Dong-A Pharmaceutical Co., Ltd. and has rights to develop and market Zydena in non-Korean markets.

Statements under the Private Securities Litigation Reform Act: with the exception of the historical information contained in this release, the matters described herein contain forward-looking statements that involve risk and uncertainties that may individually or mutually impact the matters herein described, including but not limited to FDA review and approval, product development and acceptance, manufacturing, competition, and/or other factors, which are outside the control of the Company.

Contact: Mr. Chan Won OH General Manager, International Product Development Team 252, Yongdu-Dong, Dongdaemun-Ku Seoul 130-078, Korea Tel: +82 2 920 8220 Fax: +82 2 925 4026 Email: ocw@donga.co.kr

Source: Dong-A Pharmaceutical Co., Ltd.