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Fast
Facts on Vioxx
Information on Merck's Once-Popular Arthritis Drug
Sept. 30, 2004 — Pharmaceutical
giant Merck & Co. pulled its anti-inflammatory drug Vioxx off
the shelves today in a voluntary recall after a clinical trial
found patients using the drug had an increased risk of heart
attacks and strokes. The following are some facts on the
once-popular medication.
 Vioxx is the name Merck &
Co. gave to rofecoxib, a non-steroidal anti-inflammatory drug
(NSAID) developed by the company in the 1990s.
Vioxx is classified as a
COX-2 inhibitor, a type of pain relief that works by
inhibiting an enzyme (cyclooxygenase) involved in
inflammation.
In 1999, Merck received
FDA approval for Vioxx as a treatment for pain from
osteoarthritis, acute pain in adults, and menstrual pain.
Twelve percent of adults
in the United States (about 25 million people) reported taking
prescription drugs for arthritis, according to a July 2000
Kaiser poll.
Vioxx was seen by
industry analysts as a direct competitor to Celebrex, a COX-2
inhibitor manufactured by rival Pharmacia.
The most common side
effects from Vioxx were listed as upper-respiratory
infections, diarrhea, nausea and high blood pressure.
Since its introduction,
more than 91 million prescriptions for Vioxx have been written
in the United States alone.
Advertising to consumers
and physicians helped fuel the growth of COX-2 inhibitors. In
2002, Merck spent $171 million to promote Vioxx to physicians,
while Pharmacia spent $133 million on Celebrex and another
$120 million on Bextra.
Total U.S. sales of COX-2
inhibitors (including Vioxx and Celebrex) were $4.5 billion in
2003.
Merck reported worldwide
sales of Vioxx reached $661 million for the first quarter of
2004, an increase of 30 percent from the comparable prior year
period. In markets outside of the United States, Vioxx
continues to be the best-selling arthritis and pain medicine.
In 2000, while studying
Vioxx's gastrointestinal effect, Merck researchers noted the
patients taking Vioxx had a greater number of heart attacks
than those taking naproxen, another NSAID.
In September 2001, the
FDA issued a warning to Merck for misrepresenting the safety
of Vioxx by downplaying the cardiovascular risks associated
with the drug's use. The following year, new safety
information was added to Vioxx labeling.
A Canadian study from May
2004 investigated the safety of COX-2 inhibitors. Patients in
the study using Vioxx had an 80 percent increased risk of
hospital admission for congestive heart failure compared to
those taking Celebrex.
In August 2004, an
FDA-sponsored study reported patients taking the recommended
starting dose of Vioxx (12.5 mg) had a 50 percent greater risk
of heart attacks and sudden cardiac death than patients taking
Celebrex. The same study found patients taking the highest
recommended dose (50 mg) had three times the risk of heart
attacks and sudden cardiac death.
Most patients using Vioxx
take daily doses of 12.5 or 25 mg for arthritis. A 50 mg dose
has been approved by the FDA for the treatment of pain, but
not for more than five days.
Following the release of
the FDA study, Merck issued a statement that "strongly
disagrees" with the study's findings.
In September 2004, the
FDA approved Vioxx for juvenile rheumatoid arthritis, the
first COX-2 inhibitor to be approved for JRA.
Sources: Merck & Co.,
www.merck.com, www.fda.gov, British Medical Journal, Cleveland
Clinic Journal of Medicine, ABC News Medical Unit
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