Merck reported higher-than-expected quarterly results on Friday and said it continued to expect full-year revenue to be at or near 2011 levels on a constant currency basis.
CNBC.com
The company reported third-quarter earnings excluding items of 95 cents a share, just above last year's 94 cents per share.
Revenue fell to $11.5 billion from $12.02 billion a year ago.
Analysts expected Merck to post earnings excluding items of 92 cents a share on $11.6 billion in revenue, according to a Thomson Reuters estimate.
In pre-market trade, Merck shares were flat.
The company said worldwide sales of diabetes drugs Januvia and Janumet rose 15 percent in the quarter to $1.4 billion. On the other hand, sales of cholesterol drugs Zetia and Vytorin declined 1 percent to $1.1 billion.
The company also reported a 55 percent drop in sales of Singulair, an oral medicine for the treatment of Asthma, after the drug's U.S. patent expired in August. Sales of Singulair fell to $602 million in the quarter.
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