Merck Cholesterol Drug Delayed

Drugmaker Merck & Co. announced Monday that the U.S. Food and Drug Administration (FDA) did not approve its investigational combination cholesterol-lowering drug.

The proposed drug is a combination of Merck's Zetia (ezetimibe) designed to lower bad LDL cholesterol, and Pfizer's atorvastatin, a generic version of top-selling cholesterol medication Lipitor.

Take cholesterol drugs as prescribed by your doctor.

Merck received a Complete Response Letter requesting additional data from the FDA regarding its drug application for the combination medication Monday. It was not clear what additional information would be required.

The letter advised that the review of the drug already is complete, Merck said.

Merck plans to discuss the next steps with FDA officials, and will submit new data available later this year. The company said the new information may satisfy the FDA's request.

The combination drug was designed to be more potent, and could aid patients who did not receive an acceptable cholesterol drop from Lipitor alone.