Arava: the 'sixth drug' that
may soon be under fire (Date of publication 3 December 2004)
At a recent hearing into the Vioxx affair, the FDA's Dr David Graham named five
drugs that he considers too dangerous to be on the market. However, in his
testimony, Dr Graham also cited Sanofi-Aventis' Arava as a drug he has
recommended be withdrawn. Unlike the other five drugs, Arava has largely
escaped the media spotlight, but there may yet be some tough questions asked
about its safety.
Arava (leflunomide) is marketed by Aventis, part of
Sanofi-Aventis, and recorded sales of $288 million in 2003. It is an oral
disease modifying treatment for rheumatoid arthritis (RA), and may be next in
the firing line for increased regulatory scrutiny, in the wake of the
withdrawal of Vioxx (rofecoxib).
Dr Graham, the Associate Director for
Science and Medicine in the FDA's Office of Drug Safety, cited the now familiar
list of five drugs that he considers should be removed from the market, in
response to open questioning from the Senate Finance committee. Much media
attention has been given to these five drugs, which include Crestor
(rosuvastatin), Serevent (salmeterol xinafoate), Accutane (isotretinoin),
Meridia (sibutramine hydrochloride monohydrate) and Bextra (valdecoxib). Some
of the companies involved immediately countered Dr Graham's statement,
reassuring the public of the safety of these treatments, but the mention of
Arava appears to have gone largely unnoticed.
Regulatory
approval
In his prepared testimony to the committee Dr Graham
related his past record from 20 years at the FDA, where he has recommended a
total of 12 drugs for withdrawal from the market, only two of which remain on
the market today. One of these is Accutane, mentioned in the list above, and
the other was Arava. Dr Graham stated that he and another, unnamed, FDA
colleague believe that it "causes an unacceptably high risk of acute liver
failure and death".
On November 23, 2004 the FDA announced the
strengthening of the risk minimization action plan (RiskMAP) for Accutane to
reduce the risk of birth defects associated with fetal exposure to it. Steps to
monitor the use of other drugs on Dr Graham's list, including Arava, which is
targeted at a similar market to Vioxx, may be required by the FDA.
Arava was approved in the US in 1998, 2000 in the EU and more recently in April
2003 in Japan. However in February 2004 Sanofi-Aventis reported that the deaths
of five Japanese RA patients may be linked to Arava and it recommended Arava
not be used on patients with respiratory problems. Arava had previously been
linked to at least 12 other deaths due to liver failures.
Safety
concerns
However, the FDA cleared Arava over liver side effects in
April 2004 when it denied a Public Citizen petition. This petition was backed
by Dr David Yocum, director of the University of Arizona Arthritis Center, who
previously served on the FDA's arthritis drugs advisory committee and was its
chairman for two years until late 2001. The FDA concluded that the benefit to
risk ratio for Arava was acceptable, but the disagreement with this fact by
such an experienced and prominent researcher as Dr Graham indicates a certain
conflict within the organization on this issue.
Arava is marketed as
an alternative option to methotrexate, an established treatment used in severe
RA, which has some serious side effects. The option appears to have been a
dangerous one as reports have emerged that Arava patients may have a higher
death rate than methotrexate patients. The parallel with Vioxx, marketed as a
less dangerous alternative to traditional NSAIDs, is clear.
If this
information is reassessed in light of the Vioxx inquiries currently taking
place, Sanofi-Aventis may find itself in a similar position to its fellow
pharma giant Merck & Co, not to mention the likes of Pfizer and GSK, which
are also looking on anxiously as concern mounts over the safety of products
such as Bextra and Serevent. Legal action is already underway against Arava in
the US, with lawyers advertising for clients to engage in class action
lawsuits. Despite passing almost unnoticed in the wider media reporting of Dr
Graham's 'hit list', there seems to be little doubt that Sanofi-Aventis will
shortly be forced to defend the safety of Arava: in the present post-Vioxx
climate, it appears that this drug may not survive the scrutiny.
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