The Great Pain Debate

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nces are you've had plenty of dealings with those irksome little enzymes cyclooxygenase 1 and cyclooxygenase 2, better known as cox-1 and cox-2. They're what you suppress every time you take an aspirin. Trouble is, aspirin, ibuprofen and other over-the-counter pain killers wreak havoc on the stomach lining--and kill thousands every year through internal bleeding. So last week, an FDA advisory panel gave the green light to Celebrex, the first of a new breed of drugs called cox-2 inhibitors that promise to deliver all the relief of today's pain killers with none of the side effects. Celebrex, made by Monsanto's G.D. Searle, is expected to get formal approval this week; arthritis patients will be the first to get prescriptions in the New Year.

But a manufacturer can't just muscle its way into the $5 billion pain-killing industry and not expect resistance. Even before the FDA acted, the cox-1 forces were faxing inflammatory press releases to all takers.

The principle behind the new drugs is that when pain comes calling, it's all cox-2's doing. Cox-1, which wasn't known to be a separate enzyme until 1990, is supposed to be an innocent bystander responsible for "housekeeping" functions--like preventing ulcers. At the FDA meeting, proponents of the old-style pain killers suggested that that theory might be too simplistic. "The whole area of information about cox-1 and -2 is an evolving field," says Dr. Robert Palmer of SmithKline Beecham, which manufactures Relafen, a popular arthritis drug. "There's probably a whole lot of functions we don't know about."

Tell that to Dr. Philip Needham, father of the cox-2 inhibitor, who calls the white paper Palmer presented to the FDA panel "a predictable effort to protect their drug." If you want evidence that Celebrex works, he says, just ask the 13,000 arthritis patients who took part in its trial. "We're getting letters saying, 'Please don't take us off,'" Needham says. And the side effects? Pretty close to placebo levels.

Dr. Steven Abramson, chairman of the FDA advisory panel, was impressed--and not at all surprised that the big drug companies were kicking up a fuss. "The cox-2 inhibitor will make it very difficult for them to compete," he says. Which could explain why Merck, Johnson & Johnson and Glaxo Wellcome are rushing to get their own versions into trial as fast as possible.

Does this spell the end of the humble aspirin? Not likely. Cox-1, which aspirin blocks, causes the blood clots that can lead to heart disease. Needham thinks many of us will end up popping a baby aspirin every day for our tickers and taking cox-2 inhibitors for big jobs like toothache and back pain. Sounds painless enough.