A European watchdog group has begun a review of Tredaptive, after manufacturer Merck announced on Thursday that doctors should stop prescribing the cholesterol medication.
Tredaptive is supposed to raise "good" HDL cholesterol and lower bad "LDL" cholesterol in order to prevent heart attacks, strokes and deaths.
But, the drug -- which contains a vitamin called niacin -- failed a U.S. study of more than 25,000 patients at high risk for heart problems, CBS News reported. Not only did it not prevent heart attacks, it caused side effects that the company didn't specify. Merck said that no new patients should be given the drug, but did not say that patients already receiving the medication should be taken off of it.
The full report, including what the specific side effects from the drugs were, will be out in March 2013.
Currently, tredaptive is not prescribed in the U.S., which refused to approved the drug for use without a large-scale study. The company said they will not pursue approval in the U.S. in light of the new data.
It has been available in Europe since 2008 and other non-U.S. markets, and approximately makes the company $50 million a year, Reuters reported. While removing the drug from those market will only have small effects, it will have larger implications on Merck's standing in the medical community. Merck is a $47 billion business.
Europe is supposed to have a decision on whether the drug will be allowed for patients who are already taking it in January 2013, according to Reuters.