Ozempic is just the beginning of a new era in the treatment of obesity. A review published this week looks at the emergence of similar experimental drugs that may be more effective in helping people lose weight.

McGill University researchers conducted the study, which is a review of clinical trial data surrounding GLP-1 drugs such as semaglutide (the active ingredient in Ozempic and Wegovy). Researchers have reconfirmed the safety and efficacy of today’s drugs. But they also highlighted the potential superiority of new compounds currently being developed such as retatrutide, which has helped people lose more than 20% of their original body weight in trials so far.

Semaglutide is a synthetic, longer-lasting version of the hormone GLP-1—a hormone that controls hunger and insulin production, among other things. Developed by Novo Nordisk, semaglutide was first approved for type 2 diabetes in 2017 as Ozempic, then for obesity in 2021 as Wegovy. It is far from the first GLP-1 drug to reach the public, but semaglutide is a game changer for the treatment of obesity. It has been shown to help people lose somewhere between 10% and 15% of their weight in studies, far above the average success seen with diet and exercise alone and more. more than the average results of older GLP-1 drugs.

Semaglutide isn’t the only new kid on the block, though. Eli Lilly tirzepatide mimics GLP-1 and another hunger-related hormone called GIP—a powerful combination that allows it to remove semaglutide. In clinical trials, people on tirzepatide lost 20% of their baseline weight. There are dozens of other related obesity treatments in the pipeline as well, some of which have already completed 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 such as tirzepatide, and even triple-agonist drugs such as retatrutide, which combines synthetic versions of three hunger-related hormones: GLP-1, GIP, and glucagon. These trials involved people who were obese but did not have type 2 diabetes.

As expected, they found that currently approved drugs are generally safe and effective, with tirzepatide the best so far (participants lost 17% of their body weight after 72 weeks therapy). But they also chose retatrutide as better for a shorter period of time, with participants losing up to 22% of their body weight after 48 weeks of therapy.

“We found that, of the 12 GLP-1 (drugs) identified in our search, the greatest reductions in body weight were reported in randomized controlled trials of retatrutide, tirzepatide, and semaglutide,” the researchers wrote their paper, PUBLISHED Tuesday at Annals of Internal Medicine.

Retatrutide was developed by Eli Lilly, and it is currently being tested in phase 3 trials—trials that will reach their conclusion in 2026. And this is not the only newcomer in the near future that could outslug existing drugs .

Last year, for example, the results of early trials of the drug amycretin (made by Novo Nordisk) proposed that it produces greater weight loss than semaglutide and tirzepatide. Other drug companies are working on their own competitors to Ozempic, such as Boehringer Ingelheim and dual agonist Zealand Pharma pressure cookers. Expectations are rising so high that Novo Nordisk’s stock really fell when it announced that their drug candidate CagriSema (a combination of semaglutide with the experimental drug cagrilintide) only helped people lose 22% of their weight in a recent trial, than 25% expected.

These drugs are not free of their negatives, of course. It usually causes gastrointestinal symptoms such as diarrhea and vomiting, and is tied to rare but serious complications such as gastroparesis (stomach paralysis). Another major concern is their price, with semaglutide and tirzepatide often costing over $1,000 per month without insurance coverage (which is often not provided by private and public insurers). That cost and rising demand has fueled a gray and black market for these drugs, with people turning to cheaper, but less safe compounded and fake versions.

Some experts hope that the arrival of more drugs related to GLP-1 will help reduce some of these issues, especially in terms of cost and insurance coverage. Whether that happens, we’ll have to see. But there are almost certainly more drugs to come for semaglutide and tirzepatide’s current crown as the best obesity treatments around.