NEW YORK, UNITED STATES - THE cholesterol fighter Vytorin sold by Merck and Schering-Plough failed to meet the main goal of improving outcomes in a closely-watched heart study, according to data presented on Monday.

Slightly higher incidents of cancer deaths were also seen in those taking the drug - 39 versus 23 on placebo - although the lead researcher said those could have occurred as a result of chance.

The shares of both companies fell after the data were released, with Schering off more than 15 per cent and Merck down by 7 per cent.

Researchers played down the cancer data, saying much larger studies of Vytorin have not showed increased cancer risk.

'There is no overall credible evidence of an increase in cancer,' said Sir Richard Peto, professor of medical statistics and epidemiology at the University of Oxford, who reviewed the data. 'We should not be diverted (from using Vytorin) by fears of cancer.'

Merck and Schering-Plough delayed reporting quarterly financial results, which were expected on Monday morning, so investors could first learn about the outcome of the study.

The primary composite goals of the study of patients with irregular thickening of the main valve to the aorta were broken into two sets of secondary goals and Vytorin was superior on one of those sets, researchers said.

Vytorin was significantly better than placebo in reducing atherosclerotic events, defined as nonfatal heart attacks, need for coronary artery bypass surgery or artery-clearing procedures, hospitalisation due to chest pain and strokes.

'The study has given a clear-cut answer whether lipid lowering will influence the cause of aortic stenosis and we can conclude it does not,' Dr Pedersen said.

But he noted that Vytorin did offer some benefits in reducing risk of coronary artery disease in the study.

The drug was no better than placebo on the other secondary measure of reducing aortic valve disease events - the need for surgical valve replacement, hospitalisation because of heart failure and cardiovascular death.

'Overall it looks positive. They did decrease atherosclerotic events, which is sort of what everyone expected,' said Mr Jon LeCroy, an analyst for Natixis Bleichroeder.

He said cancer fears should be allayed by results of larger, previous studies.

'But we've seen with drugs in the past any time cancer gets tagged on them sometimes the prescriptions can come off a little bit,' he added.

Vytorin did lower bad LDL cholesterol by 61 per cent throughout the study.

'The bottom line is there was a trade-off in this trial - in a reduction in some cardiovascular events and an excess of cancer deaths. It's obviously not a favourable result,' said Dr Steven Nissen, chairman of cardiovascular medicine at Cleveland Clinic, who has been critical of Vytorin use in the past.

The trial was designed to determine whether aggressive cholesterol lowering can lessen the need for surgical replacement of aortic valves, reduce cardiac death and reduce cardiovascular events, including heart attacks.

The 1,873-patient study, meant to follow subjects for a minimum of four years, is the largest formal trial ever conducted in patients with the condition, known as aortic stenosis. An estimated 2 per cent of people over age 65 have the condition, which can lead to heart failure.

Sales of the pill have suffered this year and Merck and Schering-Plough stock has fallen sharply, following Vytorin's failure to cut plaque in neck arteries in a separate trial called Enhance.

Widespread unfavourable publicity followed release of the Enhance results in mid-January and subsequent recommendations by researchers that patients first try other cholesterol fighters before opting for Vytorin.

Ms Linda Bannister, an analyst for Edward Jones, said it would have been a positive surprise had Vytorin met the main goal of the latest study, called SEAS.

'The concern is how this is going to be portrayed and perceived and is it just going to be another issue where there is a lot of negative publicity surrounding the drug,' Ms Bannister said. -- REUTERS