Merck warns docs to stop prescribing Tredaptive

Drugmaker Merck & Co. is suspending its sale of the cholesterol drug Tredaptive after initial results from a study showed that it wasn't effective and could raise the risk of some serious side effects.

The Whitehouse Station, N.J., company said Friday it is telling doctors to quit prescribing the tablets, which are not approved in the United States, and it also is advising patients to stop taking the medication only after talking to a physician.

The drug is sold in about 40 countries, including Europe. A company spokeswoman said Friday it will take a few months to implement the suspension worldwide.

Merck said last month initial results from a big, late-stage study showed that adding Tredaptive to traditional statin therapy failed to lower the risk of heart attack, stroke and related problems. The drugmaker said then that doctors should stop prescribing Tredaptive to new patients.

Results also showed that patients taking the cholesterol combination pill were more likely to suffer some serious, non-fatal adverse events that fall into several broad categories: blood and lymphatic, gastrointestinal, infections, metabolism, musculoskeletal, respiratory and skin. The company said researchers are still analyzing the adverse events, and it offered no additional details.

Merck said it made its decision based in part on a European Medicine Agency committee recommendation.

Statins are a class of drugs that have long been used to lower levels of LDL, or "bad," cholesterol and slightly raise levels of HDL, or "good," cholesterol in the blood. Tredaptive is a combination pill made up of niacin, which boosts good cholesterol, and laropiprant, which reduces the facial flushing caused by niacin.

The drug isn't a major product for Merck. It posted only $13 million in sales during the first three quarters of 2012.

Shares of Merck rose 32 cents to $43.10 in late morning trading Friday. They have traded in a 52-week range of $36.91 to $48.