For the first time, a drug has proven so effective against obesity that patients can avoid many of its worst consequences, including diabetes, the researchers reported on Wednesday.
The drug, semagglutide, from Novo Nordisk, is already marketed as a treatment for type 2 diabetes. In a clinical trial published in the New England Journal of Medicine, researchers at Northwestern University in Chicago tested semagglutide at a much higher dose as an anti -obesity.
Almost 2,000 participants, at 129 centers in 16 countries, injected themselves weekly with semagglutide or a placebo for 68 weeks. Those who took the drug lost about 15% of their body weight, on average, compared to 2.4% among those who received the placebo.
More than a third of the participants who received the drug lost more than 20% of their weight. The symptoms of diabetes and pre-diabetes have improved in many patients.
These results far exceed the amount of weight loss seen in clinical trials of other obesity drugs, experts said. The drug is a “game changer,” said Dr. Robert F. Kushner, an obesity researcher at Northwestern University’s Feinberg School of Medicine, who led the study. “This is the beginning of a new era of effective treatments for obesity.”
Dr. Clifford Rosen of the Maine Medical Center Research Institute, who was not involved in the study, said, “I think there is enormous potential for weight loss.” The gastrointestinal symptoms among the participants were “really marginal – nothing like the weight loss drugs in the past,” added Dr. Rosen, editor of the New England Journal of Medicine and co-author of an editorial accompanying the study.
For decades, scientists have looked for ways to help an increasing number of people struggling with obesity. Five anti-obesity drugs currently available have side effects that limit their use. The most effective, phentermine, causes an average weight loss of 7.5 percent and can be taken only for a short period of time. After it is stopped, even that amount of weight is regained.
The most effective treatment so far is bariatric surgery, which helps people lose 25% to 30% of their body weight on average, noted Dr. Louis Aronne, obesity researcher at Weill Cornell Medicine in New York who advises New Nordisk and studies semagglutide.
But surgery is an invasive solution that permanently changes the digestive system. Only 1% of those who qualify go through the procedure. Instead, most obese people try diet after diet with disappointing results.
The study of semaglutide confirms what scientists already know, said Kushner: Willpower is not enough. In the new trial, participants who received placebo and advice on diet and exercise were unable to see any significant difference in their weight.
Insurance companies generally refuse to pay for weight loss drugs on the market. Semagglutide is likely to be expensive. The lowest dose used to treat diabetes has an average retail price of nearly $ 1,000 a month. (Insurers generally pay for diabetes drugs, noted Dr. Kushner.)
Dr. Caroline Apovian, co-director of the Weight Management and Wellness Center at Brigham and Women’s Hospital and a member of Novo Nordisk’s advisory board, said the effectiveness of semagglutide was “phenomenal” and that the results of the study could lead to insurers to cover it.
Semagglutide is a synthetic version of a natural hormone that acts on appetite centers in the brain and intestine, producing feelings of satiety. A high-dose regimen of the drug has not been studied long enough to see if it has serious long-term consequences.
And patients are expected to take it for life to prevent weight loss from coming back.
Qiana Mosely, who lives in Chicago, has spent years trying to lose weight with diets and medications, but to no avail. Then, Ms. Mosely entered the study of semaglutida and lost 18 pounds, about 15% of her weight.
Mrs. Mosely did not know until recently whether she was receiving the drug or the placebo. Even though she was trying to eat well and exercise, her weight “was dropping very fast,” she said. “It had to be the drugs.”
She has experienced no side effects, she said. But when the test was over and she no longer received the drug, the weight started to come back. “I was very sad,” she said. She is eager to resume using the drug as soon as it is available.