CEO since 2005: Richard T. Clark
Bolstered by the $41 billion acquisition of Schering Plough and strong sales of Singulair (to treat allergies and asthma) and its hypertension and diabetes drugs, Merck posted a healthy increase in both revenues (up 15%, to $27.4 billion) and earnings (up 65%, to $12.9 billion) in 2009.
This year, Merck CEO Richard Clark has a bitter pill to swallow: patents on two hypertension drugs and a brain tumor treatment - which together bring in about $3 billion annually - are set to expire.
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