Fen Phen – A History

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Let us face it. Obesity is a real problem that most of us face. Being obese or being grossly overweight is a serious physical condition that can result to serious health problems. That’s why I find it an outrage personally that a medicine that was supposed to have helped in addressing this problem would actually lead to problems of its own! What I am talking about is fenfluramine/phentermine, which had been sold by Wyeth until 1997.

A History of Fen Phen

Of the two, fenfluramine was introduced first into the market in the 1970s as a weight-loss remedy. At that time, Wyeth was still known as American Home Products and was not able to market the drug effectively. Even though a study was undertaken in 1984 that showed fenfluramine achieving an average weight loss of 7.5 kilograms for people who was given the drug for 24 weeks, it would take another 6 years for it to be noticed by the mainstream.

By the 1990s, fenfluramine was combined with phentermine. The manufacturer then embarked on an aggressive campaign that apparently worked! That is, until the lawsuits started coming.

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A History of Problems

It should be noted that fenfluramine and phentermine is similar to a medicine called aminorex. This drug had been linked to cases of severe lung damage, and there had been concerns that the new ones (fenfluramine and phentermine) could also cause similar damages to the body. Wyeth did acknowledge the risks and published warnings in its label that there had been cases of pulmonary hypertension associated with fen-phen. However, the label only indicated 4 cases when, at that time, there had been 41 cases linked to fen-phen! An official within the company, Fred Wilson, had raised this concern but was apparently overruled.

In addition, the company introduced another drug, dexfenfluramine. The FDA officer Leo Lutwak refused to approve the drug unless Wyeth produced a black box warning in its label, but the drug was still approved without a black box as someone else signed the approval instead of Lutwak.

The problems began surfacing in 1996, beginning with a Mayo Clinic publication that detailed the story of 24 patients who took Wyeth’s aforementioned medicines and who had developed heart problems involving the mitral valve. To make matters worse for Wyeth, the Boston Herald published the story of a 30-year-old woman who suffered and died from a heart problem that developed barely a month after using fen-phen. Up until 1997, reports flooded the US FDA’s mailboxes of cardiac problems involving the aortic and mitral valves in patients who were taking fen-phen or dexfenfluramine.

On September 1997, the medicine was formally withdrawn from the US market.

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As of 2005, there was a reported 50,000 lawsuits against Wyeth in relation to its fen-phen and dexfenfluramine products. It had been reported at that time that Wyeth was pursuing settlement negotiations but was meeting stiff opposition because of the low amount proposed in the settlements.

It wouldn’t be a surprise if, eight years later, the number of cases the company faces grows exponentially as the medicine was undoubtedly popular in the final decade of the previous millennium.

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Nancy Sturgis had studied initially to become a personal injury lawyer, but had changed her mind after seeing the plight of patients that sustained unexpected side effects as the result of using medicines that were supposed to help them out. A graduate of the University of Utah, Nancy practices privately and enjoys writing articles for AttorneyOne.com to inform the public about medical updates.