Ozempic is just the beginning of a new era in obesity treatment. A review published this week anticipates the emergence of similar experimental drugs that will likely be even more effective in helping people lose weight.
Researchers at McGill University conducted the study, which was a review of clinical trial data on GLP-1 drugs such as semaglutide (the active ingredient in Ozempic and Wegovy). Researchers reaffirmed the safety and effectiveness of current drugs. But they also highlighted the potential superiority of newer compounds currently in development, such as retatrutide, which has so far helped people lose more than 20% of their original body weight in trials.
Semaglutide is a synthetic, longer-lasting version of the hormone GLP-1, a hormone that regulates hunger and insulin production, among other things. Developed by Novo Nordisk, semaglutide was first approved for type 2 diabetes in 2017 as Ozempic and then for obesity in 2021 as Wegovy. It’s far from the first GLP-1 drug to reach the public, but semaglutide has been a game-changer for the treatment of obesity. It has been shown in studies to help people lose 10% to 15% of their weight, far above the typical success seen with diet and exercise alone and even surpassing the typical results of older GLP-1 medications. .
However, semaglutide is not the only new product on the block. Eli Lilly’s tirzepatide mimics both GLP-1 and another hunger-related hormone called GIP, a powerful combination that has allowed it to dethrone semaglutide. In clinical trials, people taking tirzepatide lost up to 20% of their starting weight. There are also dozens of other obesity-related treatments in the pipeline, some of which have reached human trials and are poised to eclipse even tirzepatide.
McGill researchers analyzed data from 26 randomized clinical trials of single-agent GLP-1 drugs, dual agonists like tirzepatide, and even triple agonist drugs like retatrutide, which combines synthetic versions of three hunger-related hormones: GLP-1, GIP, and glucagon. These trials involved people living with obesity but who did not have type 2 diabetes.
As expected, they found that the drugs approved today were generally safe and effective, with tirzepatide currently performing the best (participants lost up to 17% of body weight after 72 weeks of treatment). But they also highlighted that retatrutide performed even better in a shorter period of time, with participants losing up to 22% of their body weight after just 48 weeks of treatment.
“We discovered that, of the 12 GLP-1 [drugs] “Identified by our search, the greatest mean reduction in body weight was reported in randomized controlled trials of retatrutide, tirzepatide, and semaglutide,” the researchers wrote in their paper. published Tuesday in the Annals of internal medicine.
Retatrutide is being developed by Eli Lilly, and is currently being tested in Phase 3 trials, trials that will reach conclusion in 2026. And it won’t be the only newcomer arriving in the near future that could outperform existing drugs in the market. present.
Last year, for example, early results from trials of the drug amicretin (developed by Novo Nordisk) suggested that it might provide greater weight loss than semaglutide and tirzepatide. Other pharmaceutical companies are working on their own competitors to Ozempic, such as Boehringer Ingelheim and Zealand Pharma’s dual agonist. overvodutide. Expectations have risen so much that Novo Nordisk shares actually fell when it announced that its drug candidate CagriSema (a mixture of semaglutide with the experimental drug cagrilintide) only helped people lose 22% of weight in a recent trial, instead of the expected 25%.
Of course, these medications are not without their negative effects. They commonly cause gastrointestinal symptoms such as diarrhea and vomiting, and have been linked to rare but serious complications such as gastroparesis (stomach paralysis). Another major concern is their price, as semaglutide and tirzepatide typically cost around $1,000 per month without insurance coverage (which is often not provided by public and private insurers). That cost and rising demand have fueled a gray and black market for these drugs, with people turning to cheaper, but less safe, counterfeit and compounded versions.
Some experts hope that the arrival of more GLP-1-related drugs will help reduce some of these problems, particularly cost and insurance coverage. If that actually happens, we’ll have to see. But there will almost certainly be many drugs that will replace semaglutide and tirzepatide as the best obesity treatments available.