Sometimes acquisition rumors turn out to be true. Yesterday, biotech drug developer MedImmune (NASDAQ:MEDI) announced that it was being acquired by pharma giant AstraZeneca (NYSE:AZN). AstraZeneca is paying $15.2 billion in the all-cash acquisition; this values shares of MedImmune at $58.

A deal of this size doesn't come along often in the biotech and pharmaceutical industries. MedImmune, one of the biggest biotechs in the world, is being swallowed by a pharma that has had major clinical trial setbacks with its partners in the past 12 months and is also looking to restock its dwindling drug pipeline.

I have no doubt that AstraZeneca and its larger sales and marketing division will be able to wring out more revenue from MedImmune's top products, like the $1.1 billion respiratory drug Synagis. MedImmune's other main growth driver in the near-term is expected to be the royalties that it receives on sales of the human papilloma virus vaccines from GlaxoSmithKline (NYSE:GSK) and Merck (NYSE:MRK). There's nothing AstraZeneca can do to boost this income source, since MedImmune won't be marketing these products. However, MedImmune does have other vaccines in its pipeline that AstraZeneca may be able to commercialize at a faster rate with its much deeper pockets.

MedImmune was guiding for non-GAAP earnings excluding options expenses to come in at the $0.90-per-share range for 2007. At the $58-a-share buyout price, this values MedImmune at a whopping 63 times the midpoint of this year's earnings -- which is rich even for the biotech sector, considering that MedImmune expects revenue growth in the high-teen percentages for the year. Another way to look at it is that AstraZeneca is buying MedImmune for approximately 10 times revenues.

MedImmune investors appear to be getting a pretty sweet deal.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. GlaxoSmithKline is an Income Investor recommendation; Merck is a former Income Investor pick. The Fool has a disclosure policy.

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