While Endo Pharmaceuticals (NASDAQ:ENDP) and Cephalon (NASDAQ:CEPH) search for new acquisition targets to diversify their pipeline, others, like U.K.-based Shire (NASDAQ:SHPGY), are divesting certain compounds to focus more on key franchises.

In order to concentrate on its ADHD treatments, along with recently approved compounds like enzyme-replacement therapy Elaprase, Shire sold a European pharma some of its niche-marketed products today for $213 million in cash. None of the drugs Shire sold today was a particularly big source of revenue; the top three compounds named in the sell-off accounted for a mere $34 million of Shire's $1.8 billion in revenue last year.

In 2006, sales of Shire's lead ADHD drug, Adderall XR, totaled $863 million, representing more than 55% of the company's total sales. Shire has since continued its focus on ADHD drugs with its launch of Daytrana last year and its $2.6 billion acquisition of partner New River Pharmaceuticals in February.

Shire didn't state how it would use the cash from the sale. This extra $213 million gives Shire more than $800 million in cash and equivalents on its balance sheet, against $1.1 billion in convertible debt due in 2014.

Given its predilection for acquisitions in its core areas of expertise, though, might another acquisition of an ADHD drug developer with a beaten-down share price, like Noven Pharmaceuticals (NYSE:NOVN), eventually be in order? Stay focused, Fools, and find out.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool will not divest its disclosure policy to a European pharma.