By Martin Mou

CStone Pharmaceuticals' shares rose as much as 40% on Wednesday morning after the Chinese drug maker entered into a strategic collaboration with Pfizer Inc.

Pfizer will invest US$200 million to take a 9.9% stake in CStone, which will use the fresh capital to fund business expansion, CStone said Wednesday.

CStone has agreed to grant Pfizer an exclusive license to a monoclonal antibody in China, and the two companies will also join hands in developing and commercializing additional late-stage oncology therapies in Greater China, CStone said.

CStone shares were up 12% at HK$10.44 at midday. 



  Write to Martin Mou at martin.mou@wsj.com