A rare study into the long-term effectiveness of obesity drugs like Ozempic suggests they may not shed as much fat as the advertising surrounding them claims.
Cleveland Clinic experts examined the medical records of 4,000 obese people who were prescribed different doses of semaglutide, marketed as Wegovy and Ozempic, or liraglutide, sold under the brand names Saxenda and Victoza.
On average, semaglutide caused weight loss of 5.1 percent versus 2.2 percent for liraglutide after one year.
Their findings could come as a blow to millions of Americans who had been led to expect dramatic, life-changing weight loss.
People taking semaglutide, marketed as Ozempic and Wegovy, lost more weight for at least a year than patients taking an older version, liraglutide, marketed as Saxenda and Victoza.
For someone taking Ozempic and starting out weighing 300 pounds with a life-threatening body mass index, they might lose only 15 pounds, leaving them 285 pounds overweight.
The researchers said the findings offered rare insight into the long-term effectiveness of weight-loss drugs.
These drugs have become so popular over the past three years that manufacturers and pharmacies have struggled to meet the extreme demand.
They examined medical records from January 1, 2015, to July 28, 2023, of 3,389 patients who were prescribed semaglutide or liraglutide, the older version of the more popular Wegovy and Ozempic.
Some of the patients, whose average age was 50 and average body mass index was 38.5, were prescribed one of the drugs to treat obesity, while others were given a drug for their type 2 diabetes.
On average, with both drugs, patients lost 3.7 percent of their body weight after one year.
Those taking semaglutide lost 5.1 percent, while liraglutide users lost 2.2 percent.
Breaking it down further by group, they concluded that patients taking one of the obesity drugs lost more weight than those taking it for type 2 diabetes.
Those taking obesity medications tend to start at higher doses than those being treated for diabetes, which may have accounted for the notable difference in weight loss between the obesity group and the type 2 diabetes group.
Patients taking anti-obesity medications were also more likely to continue taking them uninterruptedly for one of several reasons, such as continued insurance coverage and willingness to continue taking them long-term.
Patients taking semaglutide for obesity lost 12.9 percent of their body weight after one year, while those taking it for diabetes lost 5.9 percent.
People who took liraglutide for obesity lost 5.6 percent, while those who took it for diabetes lost 3.1 percent.
An estimated 15.5 million Americans have taken weight-loss injections like Wegovy and Ozempic at some point in their lives in hopes of losing up to 20 percent of their body weight.
Dr Shauna Levy, an obesity medicine specialist and bariatric surgeon at Tulane University who was not involved in the study, previously told DailyMail.com: “Anti-obesity drugs are not a magic bullet… They are drugs that have risks and benefits, there is no one-size-fits-all solution,” she said.
She said that for people who need serious weight loss, weight loss drugs can only take them so far.
The study aimed to determine whether people in the real world could reasonably achieve significant weight loss of 10 percent or more after long-term use.
That benchmark was chosen because research has shown that losing 10 percent of body weight can lead to significant improvements in health markers, including a lower risk of chronic diseases like diabetes, high blood pressure and heart disease.
Pre-approval studies of Wegovy and Ozempic estimated body weight loss to be between five and fifteen or twenty percent. In pre-approval clinical trials lasting more than a year, patients lost at least five percent of their body weight, with average weight loss ranging from fifteen to twenty percent.
The latest findings could deal a blow to the hopes of the roughly 15 million Americans who have chosen to take semaglutide or liraglutide to lose weight.
Semaglutide’s meteoric rise in popularity since 2021 has produced thousands of success stories of patients who have long struggled with obesity and its related health effects, such as diabetes and heart disease, and have lost 20, 50, and even over 100 pounds with the help of the drugs.
The chart shows that more than a third of patients taking semaglutide for obesity met the benchmark of losing 10 percent or more of body weight, compared with about 17 percent of those taking it for diabetes. About 14 percent of people taking liraglutide for obesity lost at least that much, as did 9 percent of those taking it for diabetes.
At the same time, drugs have taken over Hollywood, with a long list of celebrities rumored or confirmed to have taken some form of weight-loss drug to slim down before a red carpet event.
This has left millions of Americans clamoring to get their hands on these miracle drugs, leading to prolonged shortages that have forced some people to travel hundreds of miles to get them.
Cleveland doctors said: “Having real-world data could help manage expectations regarding weight loss with GLP-1 RA drugs and reinforce that persistence is key to achieving meaningful results.”
Overall, patients taking semaglutide had better outcomes than those taking liraglutide continuously for at least 90 days. Those who started with a higher BMI were also more likely to lose more weight.
Specifically, 61 percent of patients who took semaglutide for obesity and continued taking it for one year lost at least 10 percent of their body weight, similar to results in trials in which 69 percent lost at least 10 percent.
The research was published in JAMA Network Open.
The study’s greatest strength was its large and diverse patient population, which helped ensure that the people studied were truly representative of the broader population.
At the same time, they didn’t have access to other useful information about the patients, including their diet, whether they took other diabetes medications, their genetics and how their bodies respond to changes in glucose levels.