Doubts Over Safety of Arthritis Painkiller ; Drug Can Raise the Risk of a Heart Attack, Says Study

DOUBTS have been raised over a leading arthritis drug by a study which suggested it increases the risk of a heart attack.

The drug, Celebrex, is taken by around 750,000 Britons, but a long-term U.S.

trial found that it caused muscle weakening that can lead to heart attacks.

Celebrex has become the top painkiller for arthritis sufferers after a rival drug, Vioxx, was withdrawn in October because of similar problems. The two drugs work in the same way.

Manufacturer Pfizer has refused to withdraw Celebrex, saying a large number of previous studies had found no increased risk of heart problems.

But the Arthritis Research Campaign expressed concern and advised worried patients to consult their GPs.

A spokesman said: ‘The withdrawal-of Vioxx, on the grounds that it increased the risk of heart attack and stroke, makes this news about Celebrex worrying.’ An estimated 200,000 Vioxx users have swopped to Celebrex.

A spokesman for the Medicines and Healthcare Products Regulatory Agency said: ‘We will be looking at this research very carefully and advice for patients will be updated when necessary.’

Celebrex is one of Pfizer’s biggest products, with global sales of Pounds 1.18billion in the last nine months. The news wiped 20 per cent off the company’s share price.

The Celebrex trial, carried out by the U.S. National Cancer Institute, involved patients taking daily doses to prevent a particular type of tumour.

Officials decided to halt it after confirming ‘an approximately 2.5-fold increase’ in the risk of fatal or nonfatal heart attack in patients taking the drug, compared to those taking a placebo.

But Pfizer said Celebrex had not been shown to increase heart risk in a second long-term trial, designed to see if it could prevent the growth of colon polyps.

The company says its drug is chemically different from Vioxx and does not carry the same safety risk.

Both work by selectively blocking a protein called COX-2, which has been linked to inflammation.

They were both launched in 1999 and quickly became top- sellers, hailed as having fewer side effects than anti-inflammatory drugs such as ibuprofen.

Problems with COX-2 inhibitors first surfaced in 2001, when Bayer was forced to withdraw its anti-cholesterol drug Lipobay.