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NEW YORK, Jan 20 (Reuters) - Schering-Plough Corp SGP.N said on Tuesday that U.S. prescriptions for the cholesterol drugs it sells with Merck & Co (MRK.N) rose 8.7 percent in December, reclaiming most of the ground lost in November.
The U.S. drugmaker, in a regulatory filing, said combined prescriptions for Vytorin and Zetia climbed back over the 2 million mark in December to about 2.15 million from 1.98 million in November.
Citing data collected by IMS Health Inc RX.N, which follows prescription drug sales and trends for the industry, Schering-Plough said Vytorin prescriptions rose to 1.17 million from 1.08 million in November, while Zetia prescriptions climbed to 979,000 from 893,000.
Both November and December contained holidays, which can affect sales and prescriptions.
Vytorin and Zetia sales plunged last year, along with the share prices of the two companies, after a pair of clinical trials led to questions about the safety and effectiveness of the medicines.
One of the studies contained data that suggested a possible association with increased cancer risk, but the drugmakers and some researchers have said that that data was likely due to chance.
Vytorin combines Zetia with Merck’s Zocor, which is now available in generic form as simvastatin.
Total combined U.S. monthly prescriptions have plunged since January 2008, when the first controversial study shook investors.
Merck said last month it expects combined sales of Vytorin and Zetia to fall this year, due to flagging U.S. demand for the products.
Analysts have said the cloud hanging over the medicines will likely remain until long-term data on their ability to prevent heart attacks becomes available from a major study in 2011 or 2012. (Reporting by Bill Berkrot and Ransdell Pierson, editing by Leslie Gevirtz and Carol Bishopric)