Could a new pill help curb weight regain after stopping Wegovy?
A new weight loss pill helped Wegovy users maintain 95% of their weight loss after they stopped taking injections. Let's investigate.
Ask any medical professional to list the biggest advancements of recent years, and they'll likely mention injectable weight loss medications like Wegovy and Mounjaro.
The results speak for themselves. People who take Wegovy alongside healthy lifestyle changes lose, on average, around 15% of their starting body weight.¹ With Mounjaro, the average is even higher, at around 21%.²
But they're not magic wands and they're not perfect. As with most weight loss treatments, users tend to regain at least some of their weight when they stop taking their weekly injections.
This is a problem that researchers are keen to solve. And going by recently announced trial results, a new once-daily weight loss pill could help solve it.
What are the new trial results and what do they tell us?
The new results centre on a drug called 'orforglipron' and its potential for weight management after treatment with injectable weight loss medications.
The headline news, as announced by Eli Lilly, is that orforglipron helped participants maintain all but 0.9kg of the weight they lost using Wegovy (on average).³
Mounjaro users lost more weight on average than Wegovy users (24.9kg versus 18.5kg), but also regained more weight while using orforglipron (5kg versus 0.9kg).³
| Wegovy users | Mounjaro users | |
|---|---|---|
| Average starting weight | 113.5kg (250.2lbs) | 115.8kg (255.3lbs) |
| Average weight after using injections | 95.0kg (209.4lbs) | 90.9kg (200.4lbs) |
| Average weight after 52 weeks using orforglipron | 95.9kg (211.4lbs) | 95.9kg (211.4lbs) |
These results show impressive potential – particularly for weight maintenance after treatment with Wegovy.
Research shows that, on average, Wegovy users regain 11.6% of their lost weight 52 weeks after stopping treatment.⁴ In the new orforglipron trial, Wegovy users regained an average of just 4.9%.
In a key Mounjaro trial, meanwhile, eight out of 10 participants regained at least 25% of the weight they'd lost.⁵ While it's not a like-for-like comparison, these new results suggest a small improvement, with Mounjaro users regaining 20% on average.
How did the trial work?
The new trial, dubbed 'ATTAIN-MAINTAIN', is an extension to the landmark SURMOUNT-5 study. SURMOUNT-5 compared the effects of Wegovy and Mounjaro, proving for the first time that Mounjaro is more effective under identical trial conditions.⁶
In the ATTAIN-MAINTAIN trial, SURMOUNT-5 participants who had taken Wegovy or Mounjaro for 72 weeks were offered the chance to try orforglipron for weight maintenance.³
These participants were randomly selected to receive orforglipron or a placebo (dummy drug) for an additional 52 weeks.³
What is orforglipron?
Orforglipron is a weight loss drug developed by Eli Lilly. It works similarly to Mounjaro and Wegovy. However, unlike Mounjaro and Wegovy, it's taken as a once-daily pill rather than a once-weekly injection.
These new results show that orforglipron has promise as a weight maintenance treatment. However, the drug has yielded impressive results for weight loss, too. In a 2025 phase 3 trial, orforglipron users lost an average of 11.2% of their starting weight after 72 weeks of treatment.⁷
Eli Lilly has submitted orforglipron for approval by the FDA,⁸ so it might not be too long before we see it on the US market. It remains to be seen when – or if – it's approved in the UK, but we'll be sure to keep you posted.
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Sources
1. Wilding, J.P.H. et al. (2021) "Once-weekly semaglutide in adults with overweight or obesity" The New England Journal of Medicine, 384(11) https://doi.org/10.1056/NEJMoa2032183
2. Jastreboff, A.M. et al. (2022) "Tirzepatide Once Weekly for the Treatment of Obesity" The New England Journal of Medicine, 387(3) https://doi.org/10.1056/NEJMoa2206038
3. Eli Lilly and Company (2025) Lilly's orforglipron helped people maintain weight loss after switching from injectable incretins to oral GLP-1 therapy in first-of-its-kind Phase 3 trial [press release]. Retrieved from https://investor.lilly.com/news-releases/news-release-details/lillys-orforglipron-helped-people-maintain-weight-loss-after
4. Wilding, J.P.H et al. (2022) "Weight regain and cardiometabolic effects after withdrawal of semaglutide: The STEP 1 trial extension" Diabetes, Obesity and Metabolism, 24(8) https://doi.org/10.1111/dom.14725
5. Aronne, L.J. et al. (2024) "Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity: The SURMOUNT-4 Randomized Clinical Trial" JAMA, 331(1) https://doi.org/10.1001/jama.2023.24945
6. Aronne, L.J. et al. (2025) "Tirzepatide as Compared with Semaglutide for the Treatment of Obesity" The New England Journal of Medicine, 393(1) https://doi.org/10.1056/NEJMoa2416394
7. Wharton, S.W. et al. (2025) "Orforglipron, an Oral Small-Molecule GLP-1 Receptor Agonist for Obesity Treatment" The New England Journal of Medicine, 393(18) https://doi.org/10.1056/NEJMoa2511774
8. Eli Lilly and Company (2025) What to know about orforglipron: An investigational oral GLP-1. Retrieved from https://www.lilly.com/news/stories/what-to-know-about-orforglipron
This article was reviewed and approved by Lujain Alhassan, Bariatric Dietitian, and Sarah Abdula, Specialist Dietitian, on 5 January 2026.
