Risk: Cholersterol reducing pill Inegy has been linked to cancer (file picture)

A pill that lowers cholesterol and is taken by thousands of Britons has been linked to an increased risk of cancer.

Drug safety chiefs in the U.S. are investigating a report of possible higher cancer rates among patients taking Inegy, a pill combining two kinds of medication.

The Food and Drug Administration said that it is reviewing data from a trial which found a 'larger percentage' of patients treated with the drug developed and died of cancer than those taking dummy medication.

Full data from the five-year trial of heart patients will be available to the FDA in three months' time and it is expected to issue its conclusions within six months.

Inegy combines the widely-used statin drug simvastatin with a new medication called ezetimibe.

It is used to cut levels of 'bad' cholesterol, known as LDL, which should lead to a drop in heart attacks and other cardiovascular problems. Ezetimibe works in a different way to statins, which block cholesterol made in the liver.

It has a unique mode of action as it blocks the absorption of cholesterol in the gut, even among patients already on a low cholesterol diet.

More than two million Inegy prescriptions have been issued by the Health Service over the last two years. The NHS 'rationing' body, the National Institute for Health and Clinical Excellence, last November approved wider use of ezetimibe for treatment of hypercholesterolaemia, a condition leading to high concentrations of cholesterol in the blood.

Earlier this week, data from 15 trials published by the American College of Cardiology found statin drugs do not increase the risk of cancer.

Inegy, which was licensed three years ago, is marketed in the UK by Merck Sharp & Dohme and Schering-Plough, and has achieved global sales of around £2.5billion.

The FDA has not called for the drug to be withdrawn, but says doctors should continue to monitor patients and report any side effects to the agency.

A spokesman for the UK drug regulatory body, the Medicines and Healthcare Products-Regulatory Agency, said it is aware of the issue

The spokesman added: 'Any regulatory action that may be necessary to minimise harm to patients will be taken once the new information has been carefully reviewed.'

The five-year trial involving heart patients found no benefit of the drug in reducing aortic valve disease but did lead to a reduction in non-fatal heart attacks and bypass surgery.

A spokesman for Schering-Plough said: 'The data has been independently analysed by an Oxford University researcher who believes the cancer finding was probably due to chance.

'However, it is important for us to work with the regulatory authorities to make sure the data is properly evaluated.'