Vioxx Problems Known Years Before Recall
November 23, 2009
New York Times
by Natasha Singer
What could be done to prevent another Vioxx? This pain medication for arthritis became a blockbuster after its introduction in 1999, only to be taken off the market in 2004 when a study linked the drug to an increased risk of heart attack and strokes.
A new study published Monday in Archives of Internal Medicine offers an ambitious proposal to determine a drug’s risks sooner than they might otherwise become evident. The authors propose a system to examine widely prescribed drugs through safety analyses that would pool data as they emerge from various clinical trials of a medication and aggregate the information for a fuller picture of a drug’s harms and benefits.
As policy makers in Washington push for various forms of evidence gathering to determine the safety and effectiveness of medical treatments, the study proposes a broad model for monitoring drug safety that would consist of detailed publicly available data that independent researchers could freely analyze.
Such a database could be continually updated and aggregated with new information, as the results of new studies were published, to calculate a near real-time balance sheet of a drug’s risks and benefits.
Dr. Joseph S. Ross, the lead author of the study, said the objective of the researchers was to determine whether this kind of sequential cumulative analysis could serve as a new model for monitoring the safety of drugs after they enter the market.
“How could we be doing post-market surveillance in a better way?” said Dr. Ross, an assistant professor of geriatrics and palliative medicine at Mount Sinai School of Medicine in Manhattan. “For drugs that we are concerned about, that are high risk, this could be a blueprint going forward.”
Drug makers and researchers regularly conduct studies called meta-analyses in which they aggregate results from some previous studies of a drug, using the combined information to summarize the benefits and risks of a treatment. But the new study proposes a continuously updated model. Using data from Vioxx as their example, the researchers reported that Merck, the drug’s maker, could have known about the increased cardiovascular risk several years earlier if the company had used the methodology.
The cumulative analysis of the researchers showed that by May 2002 — more than two years before Merck pulled Vioxx off the market — study patients on the drug had a 39 percent increased risk of heart attack or death compared with people taking a placebo.
Dr. Ross and his co-authors have each worked as paid consultants to plaintiffs involved in lawsuits against Merck over Vioxx injury claims. The researchers used documents obtained through the litigation, including detailed data from Merck’s Vioxx studies, to conduct their analysis.
In a statement Monday, Merck questioned the methodology of the authors, saying that the researchers had used categories that were too broad. The researchers, for example, counted heart attacks and deaths that happened after patients had stopped taking Vioxx.
In 2000, a study financed by Merck had reported an increased cardiovascular risk in patients taking Vioxx compared to those taking a pain medication called naproxen. The Food and Drug Administration then asked Merck to add a warning to the drug’s label.
But Merck said that the company had conducted its own regularly updated analyses of clinical trial data on Vioxx and had not determined there was a problem until 2004.
