Safety fears wipe billions off drug shares

Richard Wray and Charlotte Moore
Saturday December 18, 2004
Source The Guardian

More than $31bn (£16bn) was yesterday knocked off the value of Pfizer, the world's largest pharmaceutical company and maker of Viagra, after doubts surfaced over the safety of one of its key drugs.

The revelation comes only weeks after rival Merck decided to withdraw its painkiller Vioxx, from the same family of drugs, because of similar fears about side- effects.

News that one of Pfizer's main drugs, Celebrex, used to combat arthritis and available on prescription in the UK, could cause heart problems emerged on a dark day for the world's drug giants. British pharmaceuticals group AstraZeneca yesterday suffered its third setback in two months as a clinical trial showed its lung cancer drug Iressa failed to help patients live longer. The news saw the value of the company, one of the UK's largest corporations, drop £2.8bn in value yesterday.

There had been hopes that the drug offered a breakthrough in cancer treatment, but a study of just under 1,700 patients showed that it appeared to have no significant life-prolonging effects.

The blow follows recent news that AstraZeneca's drug, Exanta, used to treat strokes, had been blocked by the US regulatory authority. Its anti-choles terol drug, Crestor, has also faced stiff criticism from US officials. These setbacks have called into question the future of AstraZeneca's chief executive, Sir Tom McKillop.

In New York Pfizer's shares plummeted after it said trials of Celebrex as a treatment for cancer rather than arthritis showed it more than doubled the risk of heart problems.

Celebrex, which is available in the UK under prescription, comes from the family of drugs known as Cox-2 inhibitors which includes Vioxx. Cox-2 is a protein which is believed to cause inflammation of joints.

Celebrex and Vioxx are anti-inflammatories and were launched in the US market five years ago. Celebrex is one of Pfizer's biggest selling drugs, accounting for sales of $1.9bn last year. The US group also has a second newer drug in a similar vein called Bextra which was worth $687m in sales in 2003.

New York-based Pfizer said yesterday that a trial carried out by the National Cancer Institute into the use of Celebrex to treat cancerous tumours, was halted after results showed "an approximately 2.5-fold increase" in the risk of non-fatal heart attacks in patients.

The company stressed, however, that a second trial investigating whether the drug could prevent intestinal growths did not reveal any link between Celebrex and heart attacks. Adverse findings in a similar trial caused Merck to withdraw Vioxx.

Campaigners yesterday said the European Medicines Agency was reviewing data on the potential cardiovascular effects of Cox-2 inhibitors. The US Food and Drug Administration said it had "great concerns" about Celebrex and other Cox-2 inhibitors, acting FDA commissioner Lester Crawford said last night. A statement from the FDA is likely in the next few days.

The latest news may worry patients.” The withdrawal of Vioxx on the grounds that it increased the risk of heart attack and stroke, makes this news from Pfizer that there might be similar problems with Celebrex worrying," said a spokeswoman for the Arthritis Research Campaign.

But she stressed: "There has never been any suggestion from previous data that Celebrex may increase the risk of heart problems and current prescribing advice is that Cox-2s should not be given to those arthritis patients at risk of heart attack or stroke."

A spokesman for Pfizer said the company had no plans to take the drug off the market.

Hank McKinnell, chairman and chief executive of Pfizer, said: "The cardiovascular findings in one of the studies are unexpected and not consistent with the reported findings in the second study."