Drug Safety Panel Investigating Painkillers Releases New Report

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• MARGARET WARNER:

  Last September, the popular arthritis drug VIOXX was pulled from the market after studies showed it increased the risk for heart attacks and strokes. That focused attention on an entire class of anti-inflammatory painkillers known as cox-2 inhibitors. Millions of Americans use them.

  Today, after three days of hearings from experts, an advisory panel of the Food and Drug Administration declared that three top-selling prescription drugs do, in fact, pose an increased risk for heart attack and stroke.

  But the panel said the drugs should remain on the market with warnings for those who need them. The three drugs are VIOXX, made by Merck, and Celebrex and Bextra, both made by Pfizer. For the record, Pfizer is an underwriter of the NewsHour.

  Here to tell us more is Christopher Bowe, who covers the pharmaceutical industry for the Financial Times.

  And, Chris, welcome. First of all, just give us a sense, when you're talking about the whole market for painkillers in this country, how big a stake did this class of drugs have before these latest questions were raised?

• CHRISTOPHER BOWE:

  They were very, very big drugs. All three of the drugs we're talking about were considered in pharmaceutical industry parlance, "blockbusters." Worldwide they accounted for — even with the withdrawal of VIOXX, they accounted for about $6 billion in sales last year. So these were large products and consistent growers. They had flattened off in a couple of years, but they were big.

• MARGARET WARNER:

  All right. Now explain — and I'd like to split, if I could, the decision into two categories. First of all, explain after three days of hearings what led the panel to conclude that these — this class of drugs, or these three do, in fact, pose an increased risk of heart attack and stroke — what do they base that on?

• CHRISTOPHER BOWE:

  It was quite a lengthy review, although even then they talked about having to shorten it up so they could get through all the material they could. Essentially what they based it on, most of their findings they based it on placebo-controlled trials of these drugs.

  One of the problems with these drugs used on arthritis patients was that they are almost always tested comparing against another pain drug, and that made it sometimes unclear what the trials were showing.

  And so a couple of trials using placebo as these drugs were being studied for other indications, most notably the prevention of colon polyps, showed heart signal risks with these drugs. The first one, obviously, was VIOXX in their approved trial.

  Now, the controversy really started back in 2000, when Merck found out in an old trial against Naproxen, which is sold as Aleve here in the U.S., that VIOXX showed an increase in heart attack and stroke risk. And they explained it away as Naproxen being cardio-protective, which has never really been proven.

  Anyway, there's other science. Years ago, a researcher, Garrett Fitzgerald at the University of Pennsylvania, he'd theorized — and the committee took a lot of stock in this now– that what was going on here was Cox-2 inhibition sort of changed or destabilized the hemostatic balance in the bloodstream.

  For instance, aspirin is a Cox-1 inhibitor, so that helps, you know, your blood flow and prevent heart attacks. And what Cox-2 was doing was some sort of disruption where it allowed for platelet aggregation or actually would make constriction or hypertension, potential clotting. And this is was what was the basis, they think, is the basis for why these drugs are risky.

• MARGARET WARNER:

  And were they able to A, quantify how much riskier they are than using, say, aspirin or nothing? And secondly, if they are risky, however risky they are, then why did they also decide the drugs should remain on the market?

• CHRISTOPHER BOWE:

  Yeah, one of the most interesting characterizations of the risk that I heard during the hearings was in a study by FDA — or a presentation by FDA Researcher David Graham. And a lot of the committee seemed to take this as a fairly decent characterization, although I'm not quite sure if the percentages are accurate.

  But he said that taking one of these drugs in high doses was similar to you having diabetes or being a smoker or maybe even uncontrolled hypertension or high blood pressure. At low doses it might be like a little less than smoking and diabetes and like hypertension.

  So that's kind of like the risk. If you were — if you didn't have any risk at all and all of a sudden you took one of these drugs in high doses, it was almost like adding a disease risk to yourself that was prone to heart disease.

• MARGARET WARNER:

  And so why did they say that they can stay on the market?

• CHRISTOPHER BOWE:

  They said they could stay on the market for — there were a couple of major factors. One was the complexity in pain drugs overall. There's not quite certain that if they remove this option from patients, whether taking the older drugs is completely safe.

  There are still some questions. A lot of these older pain drugs have never really been studied for safety. And so there was a fear amongst the medical experts that by removing a certain drug you would be forcing patients on to drugs that hadn't been tested as much as these had been tested.

  Moreover, these drugs were developed with the idea that they might prevent stomach bleeding that some older medications, ibuprofen, I think, and naproxen as well, cause when you use them in chronic pain. You take so much it hurts your stomach. So they didn't want to take that away, too although there's ways to get around that.

  So essentially they said there was still value in these drugs if they could pinpoint the people who use them. As one researcher said– it was Garrett Fitzgerald who came up with the original theory– he said maybe these drugs are a good example of how we can use personalized medicine, something people talk a lot about for the future.

• MARGARET WARNER:

  And, briefly, we know this isn't the final decision because the FDA does have to decide, but if they do, is there any word from Merck yet whether they would put VIOXX back on the market?

• CHRISTOPHER BOWE:

  Well, they hinted at it in a very surprising move on late Thursday night, that now that other drugs had problems, and it was a class effect, maybe they could bring it back on. Tonight they're saying that they — I think the quote is they're looking forward to discussions with the FDA.

  The committee made it pretty clear, though, that if VIOXX was returned, they said it would be possible for them to return it. But if it did, it would come with some serious restrictions, potentially not allowing people with heart disease, things like that.

• MARGARET WARNER:

  All right. Chris Bowe of the Financial Times, thanks very much.

• CHRISTOPHER BOWE:

  Sure, thank you.