Researchers Charge Pfizer Hid Data Citing Bextra RisksNov 11, 2004 | Star-Ledger
It was enough to prompt Wall Street analyst Timothy Anderson to wonder: Does Bextra stand for "Be Extra Careful?"
The controversy over the safety of some widely sold arthritis pain medicines intensified yesterday with a focus shifting to Pfizer and its medicine Bextra.
A day after presenting data at a major medical
meeting, two leading researchers criticized the
world's biggest drug maker for failing to promptly disclose scientific data they say suggests Pfizer's Bextra presents the same elevated risk of heart attack or stroke that led Merck to withdraw Vioxx last month.
"They have not been forthcoming," said Curt Furberg, professor of public health sciences at Wake Forest University School of Medicine and a member of the drug safety and risk management advisory committee for the Food and Drug Administration. "They are still claiming Bextra is safe, but they are ignoring the fact they have data showing harm in high-risk people."
But William White, a professor of medicine at the
University of Connecticut School of Medicine,
White was the principal investigator of a study
earlier this year that found Bextra did not cause an elevated risk among arthritis patients. He called the new analysis "totally erroneous" because it improperly combines date from arthritis patients with data from patients who underwent heart surgery and took high doses of medicine.
The controversy over Bextra is significant because the drug belongs to the same class of medicines as Vioxx.
It remains unclear whether the problems with Vioxx extend to similar medicines known as Cox-2
inhibitors taken by millions of consumers. The
drugs have been heavily promoted as a way to relieve chronic arthritis pain without causing stomach ulcers.
Since Merck's abrupt recall of Vioxx Sept. 30, Pfizer has said it found none of the widespread safety problems with Bextra or best-selling Celebrex. But more recently, it said two small studies of high-risk patients those undergoing heart surgery showed an elevated risk of heart attack or stroke.
The FDA has said it will hold an advisory panel
meeting early next year to consider the safety issues of the drugs. The Senate Finance Committee, which is investigating the Vioxx withdrawal, will hold a hearing next Thursday.
When Whitehouse Station based Merck recalled Vioxx,it said a clinical study of 2,600 patients started four years ago found taking Vioxx for 18 months or more led to a doubling of the risk of heart attack or stroke.
Bextra accounted for $687 million in sales last year,while Celebrex sales exceeded $3 billion. Vioxx sales were $2.5 billion.
The presentation by the two researchers consisted of an analysis of 12 trials involving 5,930 patients. The researchers conceded it is not as meaningful as a clinical trial like Merck's, which compared one medicine against another or against a placebo.
Yesterday, Pfizer issued a statement defending the safety of Bextra in response to an account in
yesterday's New York Times of a presentation by the researchers at the American Heart Association meeting in New Orleans.
Pfizer called the conclusions by the researchers
"unsubstantiated" and based on information that has not been published in a medical journal.
"Pfizer has shared Bextra clinical results in a timely manner with regulatory authorities both in the United States and worldwide," Joseph Feczko, Pfizer's president of worldwide development, said in the
In response, Furberg said he found it "remarkable how insensitive Feczko is when he says we have no evidence of harm. Baloney.
"Using the absence of data to claim the absence of a problem is a fundamental flaw, and for him to go and do that on an issue like this is inexcusable,
Asked to comment, spokeswoman Susan Bro said Pfizer has conducted extensive studies and continues to study Bextra, a relatively new medicine that went on sale two years ago.
Garret FitzGerald, a cardiologist and pharmacology professor at the University of Pennsylvania who presented the data to the medical meeting, said he was concerned Pfizer may have withheld information.
"It would be of great concern if their behavior turns out to have been purposefully deceptive, designed to increase the sales of Bextra in the wake of the Vioxx withdrawal," FitzGerald, a leading expert on Cox-2 medicines, wrote in an e-mail. "Time will tell."