Bulletin Spring‧Summer 2006

28 Chinese University Bulletin Spring • Summer 2006 Ph.D. from CUHK Improves Tamiflu Supply and Production Cost Bridgetech-CUHK Agreement to Found Clinical Research Organization B ridgetech Holdings International Inc., a company focused on maximizing the potential of emerging healthcare products and services in the US and Asian markets, and The Chinese University have set up Bridgetech MedicalTechnologyResearchandDevelopment to manage clinical trials preformed in Hong Kong and China. This new entity will oversee the State Food and Drug Administration application process and the requisite trials necessary to obtain this regulatory approval for Bridgetech’s products. Chairman and CEO of Bridgetech Mr. Michael Chermak ( right ) and director of CUHK’s Centre for Clinical Trial Prof. Benny Zee signing the agreement to set up a clinical research organization for studying new products of cancer therapeutics P h.D. chemistry graduate of The Chinese University of Hong Kong, Dr. Yeung Ying-yeung discovered a new organic synthesis that would substantially reduce the cost of production and improve the supply of Tamiflu. The discovery was made under the guidance of Prof. Elias James Corey, 1990 Nobel laureate in chemistry. Dr. Yeung is a post- doctoral fellow at Prof. Corey’s laboratory at Harvard University. The breakthrough was reported in the influential Journal of American Chemical Society . Fear of an avian flu pandemic has prompted governments around the world to stockpile the antiviral drug oseltamivir phosphate, better knownas Tamiflu. However the natural compound for its synthesis is rare and the synthetic pathway is long, making it difficult to ramp up production. At present Tamiflu is made in a 14-stage process by first extracting shikimic acid from the Chinese star anise fruit. Chinese star anise is expensive and limited in supply. Besides the drug can only be made in small quantities at a time because the process involves a highly explosive chemical. Under Prof. Corey’s guidance, Dr. Yeung and his research co-workers replaced the use of shikimic acid by an asymmetric catalytic step early in the synthesis to create a key building block. ‘Our synthetic pathway has several advantages over the current production method,’ said Dr. Yeung. ‘Our method is more efficient. It takes only 11 steps and uses inexpensive and readily available starting materials — 1,3-butadiene and 2,2,2-trifluoroethyl acrylate. We also avoided using the highly explosive chemical azides which is dangerous and slows down the synthesis process.’ This new synthesis process was reported in the influential Journal of American Chemical Society . Dr. Yeung hopes that his experience will encourage others to work on different ways of synthesizing Tamiflu. ‘Although the current supply of Tamiflu has grown, it is still expensive. We hope to reduce the drug’s price and increase its supply further so lives can be saved, especially in poor countries.’ Dr. Yeung obtained his BS in chemistry from CUHK. His keen interest in research was evident when he had a paper published in Journal of Organic Chemistry ( 2001 , 66 , 1910) as an undergraduate research assistant under Prof. Chow Hak-Fun. Dr. Yeung went on to pursue a Ph.D. in anti-cancer natural molecule synthesis under Prof. Tony Kung- ming Shing. Dr. Yeung Ying-yeung