Yamanouchi Pharmaceutical Co Ltd, a giant in Japan's pharmaceutical industry, announced that it has tied up with Pfizer Inc in order to restructure the existing partnership between the two companies in Japan.

The new agreement reaffirms the two companies' commitment to continue their ongoing collaboration on COX-2 inhibitors, which are now under joint clinical development in Japan. At the same time, it assures both companies greater freedom in independently developing and marketing their own products. To achieve this, the new pact terminates a comprehensive research and development agreement between the two companies and releases Yamanouchi from its obligation under a license agreement between the two companies to provide Pfizer a quid pro quo product. This obligation was part of the 1993 Japan license agreement between the two companies for Lipitor.

According to the agreement, they would co-develop and co-promote the COX-2 inhibitor compounds valdecoxib and parecoxib in Japan. The arrangements will be similar to the existing arrangements for celecoxib, another COX-2 inhibitor, whose NDA has been filed in Japan. The valdecoxib and parecoxib compounds will be co-developed by Yamanouchi and Pfizer distributed by Yamanouchi and co-promoted by the two companies under a single brand name in Japan.