NEW YORK, Reuters Health) -- Minor heart valve leakage caused by
the diet drug dexfenfluramine (Dexfen or Redux) disappears within 3 to 5 months
after going off the drug, researchers report in the December issue of the
Journal of the American College of Cardiology.
The drug was pulled from the market in 1997 following reports of heart
valve abnormalities in patients taking it to lose weight.
"The results of this study are reassuring for the population of patients
treated with Dexfen for 3 months or less," Dr. Neil J. Weissman of Georgetown
University Medical Center in Washington, DC, and colleagues write.
In a previous study, the researchers randomized 1,073 patients to receive
either Dexfen, an investigational sustained-release formulation called Dexfen
SR, or (an inactive) placebo.
Patients in the study underwent echocardiograms approximately one month
after going off the drug. The researchers had found that the incidence of heart
valve leakage increased, but only when the two Dexfen groups were considered
together.
To see if the heart problems persisted after going off the drug, the team
invited the patients back for a follow-up echocardiogram. A total of 941
patients underwent a second echocardiogram within 3 to 5 months after
discontinuing the drug.
Weissman's group found no significant differences between the treatment
groups in terms of the incidence of various kinds of heart valve leakage, even
when the Dexfen groups were combined. They conclude that the progression of
leakage into more serious heart damage is "unlikely."
Dexfen was voluntarily withdrawn from the market in September 1997. "This
was the biggest drug recall the (US Food and Drug Administration) has ever dealt
with and has probably cost billions of dollars if you consider the cost of
withdrawal, echocardiograms, and litigation," Dr. Nelson Schiller of the
University of California, San Francisco, commented in a press release. "If there
really is something here, it is certainly a minimal and reversible problem."
