New Study Supports Use of Embattled Obesity Drug Redux
David Tarin--The Tech
Professor of Brain and Cognitive Sciences Richard J. Wurtman, developer of the ant-obesity drug Redux.
By Christina Chow
A new report released last week to the American College of Cardiology casts doubts on a previous Mayo Clinic study which showed that the anti-obesity drug Redux caused heart valve abnormalities. Redux is the MIT-patented version of fenfluramine and was developed by Professor of Brain and Cognitive Sciences Richard J. Wurtman.
Redux once approved by FDA
Fenfluramine was first discovered over 40 years ago, but Wurtman was the first to propose its use for treating obesity.
Despite questions concerning its side effects of toxicity and hypertension, Redux was approved in 1995 by the Food and Drug Administration advisory committee. It was predicted that Redux would reach sales of $600 million a year, with MIT earning from one to five percent of the royalties.
By the time the Mayo Clinic reported possible links between Redux and heart valve abnormalities at the end of August 1997, an estimated one to five million people had already used Redux.
New study reassuring for some
Originally funded by the producers of Redux to research a way to minimize daily dosage of the drug, the new study involved 1,072 patients. Dr. Neil J. Weissman of Georgetown University Medical Center said that the study was later modified to test heart valve conditions. However, Weissman does not believe the change in purpose affected the results of the study.
The study was conducted by setting up "three groups of obese individuals: One group took [Redux] twice a day, another took it once a day, and a third group took a placebo," Wurtman said.
Wurtman said that though the test results did indicate that "there was no significant difference in heart valve conditions," questions about long term effects remain, since none of the subjects in the study had taken Redux for more than three or four months.
"I am very very happy on one hand," he said. "I don't want to be responsible for a drug that can hurt anyone."
"On the other hand, I am a little unhappy that more than one million people had expensive echocardiograms taken" because of the Mayo Clinic report, which means that roughly "one billion dollars was wasted," he said.
Serotonin causes food cravings
Wurtman's wife Judith, who is a research scientist in the Department of Brain and Cognitive Sciences, first observed in the 1970s that many obese people suffered from carbohydrate cravings. These bouts of abnormally high carbohydrate intake were linked with an increase in serotonin, a neurotransmitter in the brain.
Since consumption of dexfenfluramine was found to have the same chemical effect, Professor Wurtman hypothesized that dexfenfluramine was "the best target for an obesity drug," since it could mimic and replace the carbohydrate cravings that would often result in late-night snacking.
U.S. companies uninterested
In the early 1980s, after conducting studies on rats and humans, MIT took out a patent for dexfenfluramine and then sub-licensed the drug to Servier, a French company. Servier marketed Redux "in over 65 countries in Europe, South America and throughout the world for six to seven years without serious side effects," said Wurtman.
Though Servier tried to encourage American companies to sub-license the drug for production in the United States, there was "no interest in a drug to treat obesity at the time. They thought that if you were obese, it was your fault," Wurtman said.
Drug not marketed until 1989
Redux was not introduced in the United States until after 1989, when Wurtman co-founded the pharmaceutical company Interneuron. The company aimed to commercialize university patents, which "included getting a license for Redux," Wurtman said.
By the time the drug made the Sept. 23, 1996, cover of Time, side effects such as dry mouth and fatigue had already been noted.
In August 1997, doctors from the Mayo Clinic reported treating 24 patients who had developed heart valve abnormalities from usage of "phen-fen," an anti-obesity drug which is also a derivative of fenfluramine. Concerns were also raised about whether Redux would increase the amount of serotonin in the blood and thereby cause heart lesions.
Continued questions concerning the safety of the drug finally led to the voluntary recall of Redux, by the request of the Food and Drug Administration. In September 1997 the drug was pulled from shelves in the United States and overseas.
Wurtman said that there had been "no data collected on Redux" for the Mayo Clinic report. He also said that while an increase in blood serotonin levels would cause heart valve disease "every published paper ever written indicates that Redux lowers blood serotonin."
Redux to remain unavailable
Redux will remain unavailable for sale until further studies detailing the long-term effects are carried out. Besides the long-term effects that Redux may have on heart valve conditions, the initial health risks of hypertension and fatigue still remain.
Although the FDA has not released an official statement, CNNreports that the FDA "doesn't plan to allow the drugs back on the market, pointing to additional health risks including a rare lung disease."
Wurtman said that although he believes in certain situations obesity treatment can be "life-saving," withdrawing Redux from the market was "the moral and ethical thing to do, as it is whenever questions are raised."