AstraZeneca has entered into a definitive agreement to acquire MedImmune, Inc. for $15.6 billion in cash, approximately 11 times MedImmune’s 2006 revenues. The acquisition adds to AZ’s presence in the growing biological medicines and vaccines areas of drug research. The acquisition is expected to close this June.

The combination of MedImmune with AZ’s subsidiary, Cambridge Antibody Technology (CAT), will create a fully integrated biologics and vaccines business within the AZ Group with additional R&D, regulatory, manufacturing and global sales and marketing reach. The acquisition will allow AZ to address drug targets through three key technological approaches: small molecules, biologics and vaccines.

In 2006, MedImmune had revenues of $1.3 billion. The company’s products include FluMist nasal spray flu vaccine, Synagis for infectious respiratory disease and Ethyol for reducing chemotherapy side effects. MedImmune also has two late-stage products in development: the next-generation Synagis and a refrigerated formulation of FluMist. With the acquisition, AZ’s portion of biologics in the pipeline will increase from 7% to 27%, according to an AZ statement. MedImmune’s chief executive officer, David Mott, and its head of research, James Young, will remain after the acquisition is complete.