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 Gr...