Molecular structure of rofecoxib
Find information on thousands of medical conditions and prescription drugs.

Vioxx

Rofecoxib is a nonsteroidal anti-inflammatory drug (NSAID) that was used in the treatment of osteoarthritis, acute pain conditions, and dysmenorrhoea. Formerly marketed by Merck & Co. under the trade names Vioxx, Ceoxx and Ceeoxx, it was voluntarily withdrawn from the market in 2004 because of concerns about increased risk of heart attack and stroke. more...

Home
Diseases
Medicines
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
Hydrocodone
Vagifem
Valaciclovir
Valcyte
Valganciclovir
Valine
Valium
Valnoctamide
Valproate semisodium
Valproic acid
Valpromide
Valrelease
Valsartan
Valstar
Valtrex
Vancenase
Vanceril
Vancomycin
Vaniqa
Vanticon
Vecuronium bromide
Velcade
Velivet
Venlafaxine
Ventolin
Vepesid
Verapamil
Verelan
Vermox
Versed
Vfend
Viadur
Viagra
Vicoprofen
Vidarabine
Vidaza
Videx
Vigabatrin
Viloxazine
Vinblastine
Vincristine
Vinorelbine
Viomycin
Vioxx
Viracept
Viread
Visine
Vistide
Visudyne
Vitaped
Vitrase
Vivelle
Volmax
Voltaren
Voriconazole
Vosol
W
X
Y
Z

Rofecoxib was one of the most widely used drugs ever to be withdrawn from the market. Worldwide, over two million people were prescribed Vioxx at the time. In the year before withdrawal, Merck had a sales revenue of US$2.5 billion from Vioxx.

Rofecoxib was available on prescription as tablets and as an oral suspension.

COX-2 selective inhibitor

Rofecoxib belongs to the group of NSAIDs known as COX-2 selective inhibitors or coxibs (CycloOXygenase-2 InhiBitors). Being COX-2 selective means that these drugs act specifically on one form of the cyclooxygenase (COX) enzyme, namely the COX-2, whereas previous NSAIDs inhibited both COX-1 and COX-2. This specificity allows rofecoxib and other COX-2 inhibitors to reduce inflammation and pain while minimizing undesired gastrointestinal adverse effects - peptic ulcers - that are common with non-selective NSAIDs such as aspirin, naproxen, and ibuprofen.

Interestingly, at the time of its withdrawal, rofecoxib was the only coxib with clinical evidence of its superior gastrointestinal adverse effect profile over conventional NSAIDs. This was largely based on the VIGOR (Vioxx GI Outcomes Research) study, which compared the efficacy and adverse effect profiles of rofecoxib and naproxen. (Bombardier et al., 2000).

Adverse drug reactions

Aside from the reduced incidence of gastric ulceration, rofecoxib exhibits a similar adverse effect profile to other NSAIDs.

Withdrawal from the market

VIGOR study

The VIGOR study, published in 2000, had indicated a significant 4-fold increased risk of acute myocardial infarction (heart attack) in rofecoxib patients when compared with naproxen patients (0.4% vs 0.1%, RR 0.25) over the 12 month span of the study. There was no significant difference in the mortality from cardiovascular events between the two groups. Nor was there any significant difference in the rate of myocardial infarction between the rofecoxib and naproxen treatment groups in patients without high cardiovascular risk. The difference in overall risk was accounted for by the patients meeting the criteria for low-dose aspirin prophylaxis of secondary cardiovascular events (previous myocardial infarction, angina, cerebrovascular accident, transient ischemic attack, or coronary bypass), but who were excluded from taking low-dose aspirin in the initial design study. Once this risk was noted, Merck notified investigators in other rofecoxib studies to modify allow high-risk patients to take low-dose aspirin. (Bombardier et al., 2000)

Merck's scientists interpreted the finding as a protective effect of naproxen in reducing the risk of MI in high cardiovascular risk patients by 80 percent (which some commentators have noted would make naproxen three times as effective as aspirin). The results of the VIGOR study were submitted to the United States Food and Drug Administration (FDA) in February 2001, which led to the introduction, in April 2002, of warnings on Vioxx labelling concerning the increased risk of cardiovascular events (heart attack and stroke).

Read more at Wikipedia.org


[List your site here Free!]


Vioxx causes Merck 'adverse effects'
From Drug Store News, 9/12/05 by Michael Johnsen

NEW YORK -- "If you suspect you or a loved one has suffered adverse effects resulting from Vioxx use ... recites one television commercial paid for by product liability litigators. The ads are becoming more and more prevalent--prime time on local television networks now that the first verdict of $253 million has bloodied the product liability waters. And that spells bad news for Merck.

Already facing some 5,000 individual lawsuits, the money verdict is expected to drive more people to sue Before the statute of limitations on Vioxx lawsuits expires this time next year. Some analysts have speculated as many as 100,000 cases may be filed claiming damages from the use of Vioxx.

Whether the withdrawal of a pharmaceutical product is self-imposed or initiated by the Food and Drug Administration, more and more of that action precipitates a flood of class-action and individual lawsuits seeking damages--damages that are payed out in the billions.

To date, Bayer has spent $1.1 billion settling more than 3,000 cases revolving around its statin drug Baycol, withdrawn in 2001. There are approximately 6,000 more cases worldwide, the company stated earlier this year. And Wyeth has set aside $21 billion so far in settlements of its weight-loss drug fen phen.

With some 5,000 Vioxx liability cases facing Merck, the pharmaceutical company's total payout may very well eclipse that of either Bayer or Wyeth--Merck's potential liability is pegged at a high of $50 billion (and a low of $4 billion). But right now, it's really too early to tell, analysts are saying.

"We do not think investors should apply [the Texas] ruling to the thousands of cases Merck faces," stated David Risinger in a recent Merrill Lynch analyst note. At the end of the day, that headline-grabbing settlement running in the hundreds of millions of dollars is going to be capped well under $30 million under Texas law, and the case may very well be appealed.

Rather, people should withhold judgment regarding Merck's potential liability until a few more verdicts are in--trials in New Jersey and again in Texas are expected to begin this month with a federal trial slated for later this year.

"Merck's win/loss rate in the next half-dozen or so trials is likely to drive investor sentiment regarding the company's theoretical liability," Risinger said.

It certainly doesn't look promising, however. According to published reports, Merck's defense was too clinical and sailed over the heads of jurors. In addition, jurors are zeroing in on the fact that Merck knew about the link to heart disease and Vioxx all along, citing internal communications that date well before the recall in 2004.

All of Merck's troubles have fueled merger speculation--analysts have been considering a marriage between Merck and Schering-Plough, its pharma partner on Zetia, for years. A more likely scenario would be a hostile takeover, especially if Merck's share value dips too low. However, many analysts have been skeptical regarding such a move--in addition to assuming the Vioxx liability, Merck is on the verge of losing two blockbuster medicines to generic competition and doesn't have the pipeline to restock those lost revenues in the coming years.

Indeed, Merck is looking at losing its biggest drug, Zocor, to generic competition next year. Zocor is projected to post sales of $4.4 billion in 2005, according to analysts. And the company stands to lose a $2 billion performer, Fosamax, in 2008.

COPYRIGHT 2005 Reproduced with permission of the copyright holder. Further reproduction or distribution is prohibited without permission.
COPYRIGHT 2005 Gale Group

Return to Vioxx
Home Contact Resources Exchange Links ebay