A consumer group accused Pfizer Inc. on Monday of downplaying safety differences between its Celebrex medicine and other painkillers in a new advertisement and said U.S. regulators should ask that the ad be pulled.
Pfizer, the world’s biggest drug maker, began running television spots for Celebrex last week, after a more than two-year hiatus. Pfizer had stopped advertising for the arthritis drug after Merck & Co. Inc.’s rival drug Vioxx was withdrawn from the market. Vioxx was linked to an elevated risk of heart attack and stroke in long-term users.
Celebrex and Vioxx are both so-called COX-2 inhibitors, drugs billed as gentler on the stomach than painkillers like naproxen and ibuprofen, which are cheaper and available without a prescription. But the withdrawal of Vioxx and a similar Pfizer drug called Bextra put the class under a serious safety shadow, and sales plunged.
The COX-2 inhibitors and drugs like naproxen and ibuprofen are in a broader class of drugs, called NSAIDs, or non-steroidal anti-inflammatory drugs.
The consumer group Public Citizen in a letter to the U.S. Food and Drug Administration argued that the ad tries to lump all drugs in the NSAID class together in terms of heart risks, when there are clear differences.
“The overall purpose of the ad is to make it appear, contrary to scientific evidence, that the cardiovascular dangers of Celebrex are not greater than” others, Sidney Wolfe, director of the health group at Public Citizen, wrote. The ad may lead consumers to opt for more expensive, riskier Celebrex over “equally effective safer alternatives such as (over-the-counter) naproxen.”
A spokeswoman for the FDA was not available for comment. Pfizer said it will not pull the ad and defended its accuracy.
The withdrawal of Vioxx also led to increased public scrutiny of the role of pharmaceutical advertising, amid claims that the heavy promotion of Vioxx led to overuse.
After the Vioxx withdrawal, the FDA required all medicines in the NSAID class to carry so-called “black box” warnings, noting they pose a risk of serious heart-related problems, including heart attacks and stroke.
The Pfizer ad states that heart risks for naproxen and ibuprofen are not clear, but Public Citizen cites a review by the British Medical Journal last year finding naproxen poses no increased risk of dangerous side effects on the heart.
Pfizer senior medical director Gail Cawkwell said the medical journal study was not definitive because it was a so-called meta-analysis—a review of many studies. She also cited another clinical trial which found an increased risk with naproxen.
The Celebrex advertisement also states that the FDA requires all NSAIDs to carry the same heart risk warning, which Public Citizen said is misleading.
The American Heart Association, for example, has stated that there are clear risk differences between the painkillers and recommends that patients with heart ailments start on naproxen, with the COX-2 drugs the last choice.
“What we are trying to convey through the ad is that all prescription NSAIDs carry the same warnings. A warning is different than a risk,” Cawkwell said.
Public Citizen also called the ad misleading because it says that Celebrex carries lower rates of abdominal pain and nausea than other drugs. Public Citizen says this claim obscures the fact that all drugs in the class carry a risk of much more serious stomach problems, like bleeding and ulcers.