Celebrex - een zogeheten COX-2 remmer geeft 2,5 keer zo groot risico op ernstige hartklachten aldus gerandomiseerde dubbelblinde langjarige studie. Aandeel van producent Pfizer zakte 17% in waarde op 1 dag.

17 december 2004: Bron: Medscape, met dank aan Bob die ons dit bericht doorstuurde

Gisteren werd bekend dat Celebrex - cyclo-oxygenase (COX)-2 inhibitor celecoxib - een zogeheten COX-2 remmer het risico op zeer ernstige hartklachten met een factor 2,5 vergroot. De eerste reactie was dat het aandeel van de producent Pfizer op de beurs in Amerika met 17% daalde. Waarschijnlijk zal vermoeden wij ook Celebrex uit de handel genomen worden. Wat ons toch steeds weer verbaasd is dat dit soort studieresultaten nooit worden gemeld na dierproeven of zelfs na fase I en fase II studies? Ook hier lijkt de hand gelicht te zijn met objectieve onderzoeksresultaten zoals zo vaak schijnt te gebeuren. En de Nederlandse media? Noch NRC, noch Volkskrant noch welke krant die ik heb ingezien meldde deze studieresultaten. Over actuele onafhankelijke berichtgeving gesproken, want dit bericht was gistermiddag al rond 18.00 uur bekend, zelf gehoord in economisch overzicht op radio 1. Achereenvolgens artilel uti Medscape en persbericht van Reuters Health over Celebrex

Medscape Medical News 2004. © 2004 Medscape

Dec. 17, 2004 — The cyclo-oxygenase (COX)-2 inhibitor celecoxib (Celebrex) more than doubled the risk of cardiovascular events in subjects enrolled in the Adenoma Prevention with Celecoxib (APC) study, celecoxib maker Pfizer Inc said today.

The large randomized, double-blind, placebo-controlled, multicenter study was designed to investigate whether celecoxib could prevent colon cancer in people who had previously had colon polyps. Subjects who took celecoxib had 2.5 times as many fatal and nonfatal heart attacks as those who did not take the drug.

Patients enrolled in the trial are being told to stop taking study medication.

According to a statement from Pfizer, the Prevention of Colorectal Sporadic Adenomatous Polyps (PreSAP) trial, another ongoing study looking at whether celecoxib can prevent colon cancer, "revealed no greater cardiovascular risk than placebo." This trial used the same heart measures and the same safety monitoring board as the APC trial.

Celecoxib is in the same class of drugs as rofecoxib (Vioxx). Vioxx was withdrawn from the market after a colon cancer prevention trial found it increased the risk of heart attacks. Pfizer also manufactures valdecoxib (Bextra), another COX-2 inhibitor.
,br> "Pfizer is taking immediate steps to fully understand the [APC study] results and rapidly communicate new information to regulators, physicians, and patients around the world," Pfizer CEO Hank McKinnell says in a news release.

Investigators in the APC trial gave patients 400 mg and 800 mg doses of celecoxib per day. People who take celecoxib for arthritis are prescribed doses of 100 mg to 400 mg per day.

The APC and PreSAP trials have enrolled some 3,600 people. Some of them have been taking celecoxib for more than four years. Pfizer notes that some 2,000 people are enrolled in another study looking at whether celecoxib can prevent Alzheimer's disease in high-risk people. Some 750 of these patients are taking 400 mg of delecoxib daily. As of Dec. 10, this study's safety review board decided to proceed with the study.

Pfizer says it learned of the heart findings from the APC study last night. The National Cancer Institute (NCI) is conducting the study. An NCI spokesman tells WebMD that the trial's safety monitoring board met until 11:30 p.m. last night.

The impact of the new findings is not yet clear. Celecoxib is the ninth best-selling drug in the U.S., with 2003 sales of 2.6 billion, according to Forbes.com.

Reviewed By Michael Smith, MD.

Hier persbericht van Reuters Health over zelfde bericht:

Celebrex Trial Stopped After Heart Attacks

By Ransdell Pierson
NEW YORK (Reuters) - Pfizer Inc. on Friday said its popular Celebrex arthritis drug more than doubled the risk of heart attack in a large cancer-prevention trial, a setback that comes just weeks after Merck & Co. recalled its similar Vioxx drug due to heart safety risks.

Shares of Pfizer, a component of the Dow Jones industrial average, fell 14 percent in morning trade following news of the trial, sponsored by the National Cancer Institute.

Merck recalled Vioxx on Sept. 30 after a study found that long-term use of the drug doubled the risk of heart attack and stroke. Both Celebrex and Vioxx belong to a class of drugs known as COX-2 inhibitors.

"This does not bode well for COX-2 inhibitors in general," Ira Loss, an analyst at Washington Analysis, said of the Celebrex trial results. "The sense had been that Celebrex is somehow different from the others."

Dr. Richard Hayes, a cardiologist at New York University, told Reuters, "This raises my concern about Celebrex and all the COX-2 inhibitors, so I will no longer be prescribing any of them."

A Pfizer spokesman said the company has no plans to pull Celebrex off the market. It is one of the drugmaker's biggest products, with 2003 sales of $1.9 billion. The company also sells a newer COX-2 inhibitor, Bextra, that had sales last year of $687 million.

The U.S. Food and Drug Administration had no immediate comment.

Merck continues to sell its own newer COX-2 drug, Arcoxia, overseas. Arcoxia has not been launched in the United States, however, because of safety concerned.

Pfizer shed about $30 billion in market capitalization in late-morning trading, its stock falling to $24.80 on the New York Stock Exchange and dragging down the Dow Jones industrial average as well as other pharmaceutical stocks. Pfizer is off about 30 percent this year.

MORE TROUBLE FOR COX-2s

Pfizer said the Celebrex trial involved patients taking 400-milligram and 800-milligram daily doses of the drug to prevent tumors that grow from glandular tissue, known as adenomas. The anti-inflammatory drug was being tested on the theory that inflammation is a cause of cancer.

Vioxx and Celebrex both work by selectively blocking a protein called COX-2 that has been linked to inflammation. They were both launched in 1999 and quickly became top-selling drugs, helped by massive television and print advertising. Pfizer also said on Friday that Celebrex was not shown to increase heart risk in a second long-term trial designed to see if the drug could prevent colon polyps. Negative findings in a similar trial led to the withdrawal of Vioxx.

New York-based Pfizer said National Cancer Institute officials decided to halt the Celebrex trial on adenomas after confirming "an approximately 2.5-fold increase" in the risk of fatal or non-fatal heart attack in patients taking the drug, compared with patients taking a placebo.

"They (the NCI) will continue to follow patients in the study," said Pfizer spokesman Paul Fitzhenry, although patients will no longer be given Celebrex. "We alerted the Food and Drug Administration last night about the findings," said Fitzhenry. He said he could not elaborate on those discussions. Pfizer has argued that Celebrex is chemically different from Vioxx and does not carry the same safety risk.

Amid concerns about the safety of all COX-2 inhibitors after the Vioxx withdrawal, Pfizer plans to begin a major new trial next year to verify the heart-safety of Celebrex in arthritis patients who have had a recent heart attack.

The company has also defended Bextra's safety, although Pfizer's newer treatment raised the risk of stroke and heart attack in two small clinical trials of patients taking it after coronary bypass surgery.

The company recently updated Bextra's insert package label to warn that it can cause a rare and sometimes fatal skin disorder called Stevens-Johnson syndrome. (Additional reporting by Edward Tobin and William Borden in New York and Susan Heavey in Washington)

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