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Vioxx Woes May Not Span Class

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Vioxx Woes May Not Span Class

By SCOTT HENSLEY
Staff Reporter of THE WALL STREET JOURNAL
December 7, 2004

The painkillers known as Cox-2 inhibitors don't all carry the same risk for heart attacks, a study involving more than 8,000 people suggests.

The research from scientists at the University of Pennsylvania found that Vioxx was almost three times as likely to be associated with a nonfatal first heart attack as Celebrex.

The findings indicate that the risk of heart attack and stroke seen with Vioxx may not extend to all drugs in the class of Cox-2 medicines, as some other work has suggested.

Merck & Co. pulled Vioxx from the market after a study found it doubled the risk of heart attack and stroke compared with a sugar pill after 18 months. That action has spurred patients and doctors to ask if other Cox-2 medicines are equally risky.

"I used to be quite a believer in class effects, but the more studies that come out showing a difference within classes, the more you wonder whether you can always assume a class effect," said Stephen E. Kimmel, associate professor of medicine at the University of Pennsylvania and lead author of the paper. [That is like saying that Tarceva and Iressa should act identically in NSCLC because they are both EGFR inhibitors, however subsequent research has shown that isn't the case.]

Pfizer Inc. makes Celebrex and Bextra, the Cox-2 drugs remaining on the U.S. market. The company has stood by the safety of both medicines. Pfizer has pledged to fund a prospective study of Celebrex compared with a placebo to see if the drug may protect against heart attacks. The company has also said it would assess the cardiovascular safety of Bextra, which increased the risk of heart attack in a study of patients recovering from coronary bypass surgery.

The latest results appeared in the online edition of Annals of Internal Medicine yesterday.

The study involved more than 1,700 patients, aged 40 years to 75 years old, who suffered a first heart attack that didn't kill them between May 1998 and December 2002. A comparison group of 6,800 patients was culled from the same five counties where these people lived. In the heart attack group, 27 patients had taken Vioxx, 18 had taken Celebrex and 1,354 patients hadn't taken either of those drugs or other nonsteroidal anti-inflammatory drugs, such as ibuprofen.

Both heart-attack survivors and the comparison patients were interviewed about their health history and habits, as well as the medicines they took. Retrospective studies like this one have limitations, such as the possibility that people don't accurately recall or report important health information. The selection of patients for the control group might also distort the results. Only half of eligible patients completed the interviews.

The study was funded by grants by the National Institutes of Health, Merck and Pfizer.

A Merck spokesman said, "Observational studies on the risk of cardiovascular events with Vioxx have had inconsistent results, and this study only adds to that literature." A Pfizer spokeswoman said the findings are "consistent with the data we've amassed."

Write to Scott Hensley at [e-mail]1 <<