Celebrex Seems to Lack Risk of Vioxx

New research suggests that top-selling pain reliever Celebrex does not carry the same heart attack risk as Vioxx, a similar drug pulled from the market in September because of safety concerns.

The study by researchers at the University of Pennsylvania is the first to compare the two arthritis drugs since the recall, and it contradicts claims by other scientists that all “cox-2 inhibitors” may carry similar dangers.

“Vioxx and Celebrex look different. Relative to Celebrex, Vioxx had about a threefold greater risk of heart attacks,” said Dr. Stephen Kimmel, an associate professor of medicine and epidemiology and the lead author of the study.

The study, funded by the makers of both drugs and the federal government, was published in today’s Annals of Internal Medicine. Researchers surveyed 1,718 patients in the five-county Philadelphia area who had heart attacks and were treated at one of 36 hospitals. A comparison group of 6,800 people in the region was also surveyed.

The chances of having a heart attack were 2.72 times greater in Vioxx users than in Celebrex users, the researchers said.

But they also found that patients using either drug were not at a significantly greater risk of having a heart attack than those who did not use either drug. In fact, Celebrex users had a lower risk of an attack than people who didn’t take either drug, though the researchers said that finding could have happened by chance.

In an accompanying editorial, two Boston doctors warned that the connection between heart disease and cox-2 inhibitors remains unclear.

As a result, they recommended that doctors avoid prescribing any drug in that class to patients already in danger of heart disease, unless they run a significant risk of gastrointestinal problems. Cox- 2 inhibitors are believed to be easier on the stomach than other pain relievers.

“We don’t think that we really understand what is triggering the increased risk of heart problems in some patients,” said Dr. Axel Finckh, a rheumatology researcher at Brigham and Women’s Hospital.

Merck & Co. pulled Vioxx from the market Sept. 30 after a study indicated it doubled the risk of heart attacks and stroke when taken for longer than 18 months.

Dr. Garret FitzGerald, a Penn cardiologist and pharmacologist, questioned whether the study proved anything new. He is among a number of doctors concerned that all cox-2 inhibitors, which block the enzyme that causes the pain and swelling of arthritis, may raise the risk of heart problems.

Studies done five years ago – when Celebrex and Vioxx were approved – suggest the same mechanism that inhibits inflammation and makes the drugs easier on the stomach also blocks a substance that prevents heart problems, Dr. FitzGerald said.