BOSTON—Merck’s recalled pain reliever Vioxx carries an increased risk of kidney and heart arrhythmia problems, and can be harmful even when taken for a short period of time, according to two new analysis to be published in the Journal of the American Medical Association.
A first study, conducted by researchers at the University of Newcastle in Australia, showed that Vioxx could raise the risks of cardiovascular problems, particularly heart attack, within one month of use.
Merck & Co. (MRK) has maintained that Vioxx can cause cardiovascular problems after only 18 months or more of use. The company pulled Vioxx from the market in September 2004 over such safety concerns. It currently faces over 14,000 lawsuits filed by former Vioxx users who claim they were injured by the drug.
Although the Food and Drug Administration has said that Vioxx, also known as rofecoxib, can return to the market with restrictions, Merck has yet to do so.
“The data do not point to a safe dose level with rofecoxib, which justifies the decision taken to withdraw the drug from sale,” wrote the Australian researchers.
A second analysis said of old Vioxx data showed that the drug increased the risk of suffering renal problems and heart arrhythmia. That analysis was conducted by researchers at Harvard School of Public Health, Boston’s Brigham and Women’s Hospital and Harvard Medical School.
The researchers added that the risks were seen only with use of Vioxx, and not with similar products such as Pfizer Inc.’s (PFE) Celebrex. They also noted that if a meta-analysis had been conducted sooner on the data, the safety issues probably would have been detected.
“Another key finding in this meta-analysis is that the adverse renal effects of rofecoxib (Vioxx) were apparent in the body of studies dating back to 2000, if careful safety monitoring of the data had been carried out,” the researchers said in a statement.
“However, the adverse effects of rofecoxib were not known to physicians or the public because aggregation of cumulative safety data is not required and normally carried out, and the current passive monitoring system, such as FDA’s MedWatch program, relies on voluntary spontaneous reporting of adverse drug events by general physicians and consumers,” the researchers added.
Both analysis will appear in the Oct. 4 edition of the Journal of the American Medical Association. End of Story