September 30, 1999 18:38
U.S. study finds no heart damage from diet drugs
By Maggie Fox, Health and Science Correspondent
SAN FRANCISCO, Sept 30 (Reuters) - Boston researchers said on Thursday they had been unable to find evidence that people who took the popular "fen-phen" diet combination had a higher-than-usual rate of heart disease.
The findings will add to the controversy surrounding the drugs, which were pulled off the market in 1997 after allegations that they damaged the heart valves of some people.
They may also bear on lawsuits being filed against the companies that made the drugs.
"In contrast to some previous reports, we found no evidence of a high rate of valvular disease among people who took fen-phen," Dr. Andrew Burger, of the Beth Israel Deaconess Medical Center in Boston who led the study, said in a statement.
Writing in the Journal of the American College of Cardiology, Burger said he suspected many people have abnormal heart valve function but show no symptoms of it.
And in a commentary in the same journal, Dr. Nelson Schiller of the University of California at San Francisco suggested the early studies that led to the drugs' withdrawal had been sloppily done. The diet
drugs fenfluramine and its close chemical cousin dexfenfluramine were wildly popular among dieters because they worked as appetite suppressants.
But they were quickly withdrawn after the U.S. Food and Drug Administration reported 28 serious cases of heart valve disorders in people who took the drugs, usually in an unapproved combination known as fen-phen. Three died.
Fenfluramine, sold under the name Pondimin by Wyeth, a division of American Home Products , as well as by A.H. Robins Co., and dexfenfluramine or Redux, developed by Interneuron Pharmaceuticals Inc., were recalled.
Phentermine, the "phen" in fen-phen, has been available since 1961 and was not banned.
Four million people had taken Pondimin and two million took Redux before they were recalled.
Burger and his colleagues studied the echocardiograms of 226 people who had been taking fen-phen as part of a large clinical trial.
Independent experts who evaluated the echocardiograms found significant aortic valve disease in 6.6 percent of the patients and mitral valve disease in 1.3 percent. None had any obvious symptoms, and Burger said his team found similar rates of disease in people who never took the drugs.
Unlike some other studies, they found no evidence that people who took the drugs for longer had higher rates of valve disease.
"As studies have become more scientifically rigorous, the role of fen-phen in valve disease appears to be approaching the vanishing point," Schiller wrote in his commentary.
He complained of an "almost universal misapplication of echocardiography" to evaluating whether people's valves were damaged.
American Home Products, which is facing 4,100 lawsuits from plaintiffs who claim they were not adequately warned about the possible side-effects of Redux and Pondimin, has not argued about the
drugs' effects. Instead, the company has said it is trying to reach a national settlement with former users of the drugs.
According to published reports, it has offered to pay plaintiffs $4 billion over a 15-year stretch -- $1.2 billion to finance medical checkups and $2.8 billion for injury claims. |
