Vioxx Study Results

In the past few years, Vioxx study results have caused much concern about the link between Vioxx and serious heart, liver, and kidney problems.

FDA/Kaiser Permanente Study
Results from a recent Vioxx study financed by the U.S. Food and Drug Administration caused Kaiser Permanente, one of the largest U.S. health maintenance organizations, to reconsider its use of Vioxx.

In the study, medical records of 1.4 million people insured by Kaiser Permanente were analyzed. The outcomes of 40,405 patients who took Celebrex (Pfizer's arthritis drug) and 26,748 patients who took Vioxx (Merck's arthritis drug) were compared. Patients taking the typical starting dose of Vioxx had a 50 percent greater chance of heart attacks and sudden cardiac death than patients taking Celebrex. Patients taking the highest recommended daily dosage of Vioxx had three times the risk of heart attack and sudden cardiac death as patients not taking standard painkillers.

Merck Vioxx/Naproxen Comparative Study
During Merck’s 8,000 patient pre-market trial of Vioxx, more than two times the number of patients taking Vioxx had heart attacks and strokes than patients taking naproxen (one of the older NSAIDS). Merck claimed Vioxx did not cause the heart attacks but that naproxen prevented them.

Cleveland Clinic Study
Heart researchers at the Cleveland Clinic Foundation found that Vioxx may increase the risk of heart attacks and other cardiac side effects. As a result these researchers are warning doctors to think twice about prescribing Vioxx to patients who have a history of heart disease. The study was reported in the Aug. 22 issue of The Journal of the American Medical Association.

According to the report, people taking Vioxx are twice as likely to have heart attacks as people who take older anti-inflammatory drugs to treat arthritis. In the study of 8000 people 161 patients had heart attacks and 70% of them were taking Vioxx.

VIGOR Study
The VIGOR trial involved 8,000 patients and evaluated the gastrointestinal profile of Vioxx 50 mg. (twice the highest chronic dose approved for osteoarthritis) to the older NSAID, naproxen.

In November 2000, the VIGOR study showed 50 milligrams a day of Vioxx reduced the risk of serious stomach problems by 50 percent when compared to prescription strength naproxen (Aleve). This Vioxx dosage is considered to be relatively high, but what surprised researchers was that the Vioxx use created a two to four times higher risk of heart attack. At the start of 2004, researchers from Brigham and Women's Hospital concluded after comparing high doses of Vioxx to high doses of Celebrex that Vioxx users are linked to a 70 percent increase in heart attack risk in the first 90 days of use. Following the VIGOR trial, the Arthritis Advisory committee felt that Vioxx's label should include warnings based on the fact that Vioxx had twice the risk of heart attacks and cardiovascular side effects as naproxen users.

CLASS Study
The CLASS trial involved 8,000 patients, mostly female, average 60 years of age, with rheumatoid arthritis or osteoarthritis. The trial compared 800 mg. Celebrex (4 times the recommended daily dose for osteoarthritis, and twice the recommended daily dose for rheumatoid arthritis) to normal doses of ibuprofen and diclofenac.

On February 7th and 8th (2001), the FDA Arthritis Advisory Committee met in Gaithersburg, Maryland, to review the study results and to assess if either Celebrex or Vioxx should have warnings on their label reduced or any changes made to the prescribing information.

After analyzing results from the CLASS study, the committee concluded that a "clinically meaningful" safety advantage of Celebrex over older NSAIDS had not been established. Though the CLASS trial did demonstrate an overall reduction in gastrointestinal complications, the trend did not hold up among patients who also took low dose aspirin. Among the group of patients who also took low dose aspirin, Pharmacia did not demonstrate a superior safety record over ibuprofen or pooled NSAID data. The CLASS study also did not demonstrate a superior safety record over NSAIDS among patients with ulcer complications. Based on this information, the Arthritis Advisory Committee advised that further studies be done to assess the risk of COX-2 drugs and NSAIDS when taken with aspirin. The committee did not recommend any label changes for Celebrex.

Journal of American Medical Association 2001 Report
The Journal of the American Medical Association reported in 2001 that Vioxx and Celebrex increased the risk of suffering a heart attack twice as much as patients taking the arthritis drug naproxen. The FDA required Vioxx labels include warnings of the possible increased risk of heart attacks in 2002.

Oregon’s 2002 Revelation
Oregon’s state health plan found in 2002 that highly promoted Vioxx worked no better than just over the counter ibuprofen. The cost difference between Vioxx and ibuprofen however is significantly different, with ibuprofens costing as little as 10% of the brand name drugs.

Studies continue to indicate what was once believed to be advantageous aspects of Vioxx and Celebrex may not exist. Arthritis and drug specialists reviewing published research are now wondering if consumers have been paying six times more for Vioxx and Celebrex over older medications without evidence that the Cox-2 inhibitors are any better at fighting pain.