Concern raised again about heart drugs Zetia and Vytorin

The editors of the New England Journal of Medicine have raised concern regarding the cholesterol-lowering drugs Zetia and Vytorin.

They say, following reports linking the drug to a higher risk of dying of cancer, more research is needed.

In three clinical trials researchers found that patients had a 40% higher chance of dying of cancer if they took Vytorin instead of a placebo - Vytorin is a combination drug containing ezetimibe, the generic name for Zetia and is used in Australia.

The study known as SEAS, raised questions about potential cancer links, and whether Vytorin helps prevent cardiovascular problems better than a placebo.

Drug makers Merck and Schering-Plough have defended the drug and say ezetimibe showed no cancer risk in animal trials and that the cancer finding is probably a result of chance.

However the editors of the journal say it is "appropriate to raise a note of caution" as whether the increased mortality risk is due solely to chance, is uncertain.

The editors say ezetimibe interferes with the gastrointestinal absorption not only of cholesterol, but also of other molecular entities that could conceivably affect the growth of cancer cells and the fact that the combined data from all three trials showed an increase in cancer deaths linked to the drug, should not be assumed to be a chance until further research is done.

The journal had previously published the report also saying a cancer link was likely due to chance.

When the SEAS study was presented at the European Society of Cardiology meeting in Munich, the lead investigator Terje Pedersen, from Ulleval University Hospital, Oslo, said that the increased risk of cancer "could have occurred as a result of chance."

The results were made public in July when a prominent Oxford University researcher Dr. Richard Peto said the cancer risk wasn't credible; it now remains to be seen what action will take place.