One small South Korean bioscience firm with big ambitions claimed on Thursday to have pinpointed exactly how Viagra and other impotency drugs work.

The discovery will enable Korean scientists to ease unwanted side-effects and concentrate on the bigger issue at hand, says company president and chief executive Cho Joong-myung.
   
Founded three years ago, CrystalGenomics said it hoped to cash in on the technology through a domestic initial public offering in the second half of 2004 and a Nasdaq listing in the next two or three years.
   
Hard science

Viagra and other anti-impotency drugs all work by blocking an enzyme called PDE-5, which affects blood flow to the penis.
   
With findings published in the latest edition of "Nature" magazine, the firm said it had discovered the mechanism whereby the three drugs combine with PDE-5 at an atomic level.
   
After taking impotency drugs, unselective binding with other PDE proteins occurred which in turn caused unwanted side-effects. 
   
Understanding how the binding works was the key to producing drugs with fewer side effects, said the company, which has 47 scientists involved with the project. 
   

"The name of the game is to find a good area in gene technology faster that anyone else"

Dori Lim, 
biotechnologist at Samsung

The firm also plans to make applications for improving asthma and obesity treatments.
   
Getting bigger

Joong-myung said the company was seeking to collaborate with a major pharmaceutical company and had previously held talks with large British and US-based drug companies.
   
"We expect to become a major company in the drug discovery field within the next five to 10 years", Cho told a news conference.
   
Analysts said the technology looked interesting, although to grow bigger and commercialise would require more cash.
   
"The name of the game is to find a good area in gene technology faster that anyone else", said Dori Lim, pharmaceutical and biotechnology analyst at Samsung Securities. 
   
Stiff competition

"There are not many biotech companies [in Korea] that can be called promising at the moment," he added.
   
Pfizer Inc succeeded in making Viagra a household name, although now faces growing competition. The world's largest drugmaker secured sales of $1.74 billion from the drug last year.
   
Bayer AG and GlaxoSmithKline Plc recently won US approval for their anti-impotence pill, Levitra, while Eli Lilly & Co and Icos Corp have a joint venture producing another anti-impotence pill, Cialis.