FDA calls for urgent warning on tendon risks
WASHINGTON (AP) - July 8, 2008 The Food and Drug Administration ordered makers of
flouroquinolone drugs - a potent class of antibacterials - to add a
prominent "black box" warning to their products and develop new
literature for patients emphasizing the risks.
Tendon ruptures are normally thought of as sports injuries,
generally occurring usually among men in their mid-thirties. The
link to treatment with the antibiotics is highly unusual, and
scientists still don't fully understand why it happens. However,
FDA officials stressed that many of the serious injuries appear to
be preventable if patients stop taking the drug at the first sign
of pain or swelling in a tendon, call their doctor, and switch to
another antibiotic.
The two leading drugs covered by the warning are Cipro, made by
Bayer, and Levaquin, which is made by Ortho-McNeil. Cipro became a
household name during the anthrax attacks of 2001. It is effective
against that deadly bacteria, and is among the medications
stockpiled by the government in case of a bio-terror attack. In
everyday medicine, Cipro is often used to treat urinary tract
infections. Levaquin is generally used to treat respiratory
infections.
The FDA's action came after the consumer group Public Citizen
petitioned-and later sued-the agency for such warnings. Regulators
took too long to act, complained Sidney Wolfe, head of the consumer
group's health section. Many injuries "would have been prevented
if patients and doctors had known a pain in the tendon is an early
sign that leads to rupture," Wolfe said. Public Citizen's original
petition was filed nearly two years ago.
FDA officials pointed out that prescribing literature for the
drug class already carried clear warnings of the risk of tendon
rupture. They said the agency acted to emphasize the warnings
because continued reports of injuries indicated that the message
may not have gotten through to doctors and patients.
"The continued reports demonstrate additional steps are
warranted to better manage the risk of tendon rupture," said
Renata Albrecht, director of an FDA office that focuses on unusual
microbes.
FDA officials said they had received several hundred reports of
tendon ruptures, but would not cite a specific number. Wolfe, of
Public Citizen, said the number was 407 at the end of 2007, with
another 341 reports of tendinitis. He continued to criticize the
agency, saying it should also require drug makers to send
individual letters to doctors about the risks. FDA officials said
manufacturers could choose to send such letters on their own.
Tendons are cords of tissue that join muscles and bones, and are
essential in movement. The most common kind of rupture reported to
the FDA involved the Achilles tendon in the heel, but some also
involved the rotator cuff in the shoulder, and tendons in the
hands, biceps, and even the thumb.
Some of the ruptures reported to the FDA occurred without
warning - the patient felt a snap or pop soon after starting
treatment. That suggests flouroquinolone antibiotics may be toxic
to some people, the FDA said.
But typically, patients felt some kind of pain or inflammation
for a week or two before they suffered a tendon rupture. That
suggests that many of the most serious problems can be avoided if
patients stop the drug, officials said.
The FDA's analysis found that patients with the highest risk of
problems include people over 60, those with kidney, heart and lung
transplants, and those also taking steroids.
On the Net: http://www.fda.gov/cder/index.html