The diabetes drug liraglutide can help obese people who don't have diabetes lose weight and keep it off, new findings confirm.
Researchers found that 63 percent of study participants given liraglutide for 56 weeks lost at least 5 percent of their body weight — the amount experts agree is needed to make a difference in obesity-related health problems — whereas just 27 percent of the placebo group lost that much.
"It is a very effective drug. It seems to be as good as any of the others on the market, so it adds another possibility for doctors to treat patients who are having trouble either losing weight or maintaining weight loss once they get the weight off," said Dr. Xavier Pi-Sunyer, a professor of medicine at Columbia University Medical Center in New York City, and first author of the new study published today (July 1) in the New England Journal of Medicine. The company Novo Nordisk, the maker of liraglutide, funded the research.
Liraglutide has been available in the United States for treating people with diabetes since 2010. The drug mimics a naturally occurring hormone called glucagon-like peptide-1, which is released in the human intestine and reduces hunger, increases satiety and slows the rate at which the stomach empties its contents into the small intestine. The Food and Drug Administration approved liraglutide (at a higher dose than is used for diabetes) for treating obesity in December 2014.
In the new study, Pi-Sunyer and his colleagues randomly assigned 3,731 men and women with a body mass index of at least 30, or a BMI of at least 27 if they also had high cholesterol or high blood pressure, to receive a 3.0-milligram dose of liraglutide daily, or a placebo shot. Study participants also received counseling on ways to change their lifestyle to promote weight loss. About 2,500 patients in the study were given liraglutide, and about 1,200 were given the placebo injections.
After 56 weeks, the participants on liraglutide lost an average of 18.5 pounds, compared with 6.4 pounds for the people on the placebo. Among the patients on liraglutide, 33 percent lost at least 10 percent of their body weight, whereas just 11 percent of the placebo group lost that much. [7 Biggest Diet Myths]
The most common side effects of the drug were nausea and diarrhea. Patients on the medication were also at increased risk of gallbladder-related problems, which, the authors noted, could have been due to their above-average weight loss.
Starting patients at a lower dose and then increasing it gradually helps reduce gastrointestinal side effects, Pi-Sunyer said. For most patients, the nausea went away after they had been on the drug for four to six weeks, he added.
Drawbacks to the medication include its high cost — about $1,000 for a month of treatment — and the fact that it must be given by injection. Currently, most insurers don't cover liraglutide for treating obesity. Also, Pi-Sunyer said, patients will probably have to be on the drug indefinitely to maintain weight loss.
Nevertheless, "every tool we discover for obesity is good news," said Dr. Elias Siraj, a professor of medicine at Temple University School of Medicine in Philadelphia, who was not involved in the new study but co-authored an editorial accompanying it in the journal. "The reason is, we are in the midst of a huge global obesity epidemic, and there's no question it has not been easy to manage obesity."
Many of the people in the study who lost weight on liraglutide remained obese, Siraj said, although this doesn't mean they didn't benefit from losing weight. "Previous studies have shown if you lose more than 5 percent of your body weight, it may not make a difference in how you look from outside, but it does make a difference in terms of metabolic parameters and cardiovascular risk factors," he said.
The patients who will likely benefit the most from liraglutide are those with diabetes, high blood pressure, cholesterol and other obesity-related problems, he added. "You can't make a blanket recommendation that everyone should be on it," he said. "Cost is going to be an issue initially, but hopefully down the road the cost will get better."
The increased risk of gallstones and other problems associated with liraglutide should be investigated further, Siraj said. "There is always room for caution until we have long-term data."
"While there's room for options, we also have to note that this is not a cure," he told Live Science. "Fundamentally, obesity is a disease of lifestyle — diet and exercise — and therefore lifestyle modification has to be the core, no matter what you do. Medications alone are not going to do it."
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