Metabolic / Published Sep 8, 2026 / Reviewed Sep 27, 2026 / 9 min read
Retatrutide vs Tirzepatide vs Semaglutide vs the Pill: The 2026 GLP-1 Field Guide
Written by Aaron CuhaReviewed Sep 27, 2026
One table with the headline weight-loss numbers, the study each came from and how long it ran, so a 36-week result from a mid-sized study is never compared with an 80-week result from a big one by accident. Covers retatrutide, tirzepatide, semaglutide, CagriSema, MariTide, amycretin, eloralintide, enicepatide and the pills. Plain English.
Key takeaways
- In its big TRIUMPH-1 study (May 2026, 2,339 people), people on 12 mg of retatrutide lost 28.3 percent of their body weight on average over 80 weeks. That is the highest of any big final-stage study. It is not approved yet, and Lilly expects to ask for approval in late 2026.
- Among approved shots, tirzepatide has the biggest reported number: 20.9 percent in SURMOUNT-1 at 72 weeks. Semaglutide 2.4 mg gives about 15 percent. The new 7.2 mg dose gives 18.7 percent (STEP UP, counting everyone who started).
- Pills: orforglipron (Foundayo, approved April 2026) took off 11.2 to 12.4 percent at 72 weeks, depending on how you count. The Wegovy pill (approved December 2025) took off 13.6 percent at 64 weeks, counting everyone who started. Aleniglipron took off 16.3 percent more than a dummy pill at 44 weeks, and big studies are starting.
- 12.5 percent of people on 12 mg retatrutide in TRIUMPH-1 reported skin tingling or sensitivity (dysesthesia), and 20.9 percent in the smaller TRIUMPH-4. Tirzepatide doesn't cause it. Wegovy HD showed something similar (about 23 percent).
- The most common mistake is comparing numbers from studies of different lengths, doses and people. The table below puts the length next to every number.
Is retatrutide better than tirzepatide?
Direct answer
In its big TRIUMPH-1 study, people on 12 mg retatrutide lost 28.3 percent of their weight on average over 80 weeks, against 2.2 percent on a dummy shot. In a separate study, tirzepatide took off 20.9 percent. Retatrutide is not approved; Lilly expects to ask in late 2026. 12.5 percent on the top dose reported skin tingling (dysesthesia), which tirzepatide doesn't cause.
For the two side by side on the same measures, with the dose boxes and the evidence in people counted, see the retatrutide vs tirzepatide comparison. This guide puts the whole 2026 field in one table.
Nobody has tested retatrutide against tirzepatide in the same study, and maybe nobody ever will. What exists are separate studies with different lengths, doses and people. The table below is built to make that easy to see. For how each works and its studies, each name links to its profile. For side-by-side data, use the comparison pages.
The numbers, with their studies and how long they ran
| Drug | What it copies | Study | How long | Weight lost | Status |
|---|---|---|---|---|---|
| Retatrutide 12 mg | GLP-1, GIP and glucagon | TRIUMPH-1 (big final-stage study, 2,339 people) | 80 weeks | 28.3% (2.2% on a dummy shot); 45% lost 30% or more | Not approved; approval request expected late 2026 |
| Retatrutide | All three | TRIUMPH-4 (people with knee arthritis) | 68 weeks | 28.7% | Not approved |
| Tirzepatide 15 mg | GLP-1 and GIP | SURMOUNT-1 (big final-stage study) | 72 weeks | 20.9% | Approved (Zepbound) |
| CagriSema | GLP-1 plus amylin | REDEFINE 1 (big final-stage study) | 68 weeks | 20.4% counting everyone who started; 22.7% for people who kept taking it | Sent to the FDA December 2025 |
| Semaglutide 7.2 mg | GLP-1 | STEP UP | 72 weeks | 18.7% (20.7% for people who kept taking it) | Approved March 2026 (Wegovy HD) |
| Semaglutide 2.4 mg | GLP-1 | STEP 1 (big final-stage study) | 68 weeks | About 15% | Approved (Wegovy) |
| Semaglutide pill 25 mg | GLP-1 (peptide pill) | OASIS 4 | 64 weeks | 13.6% (16.6% for people who kept taking it) | Approved December 2025 (Wegovy pill) |
| Orforglipron 36 mg | GLP-1 (small-molecule pill) | ATTAIN-1 (big final-stage study) | 72 weeks | 11.2% counting everyone who started; 12.4% for people who kept taking it | Approved April 2026 (Foundayo) |
| Ribupatide 6 mg | GLP-1 and GIP | Big final-stage study in China (567 people) | 48 weeks | 19.2% | Sent for approval in China; big studies worldwide |
| Enicepatide 24 mg | GLP-1 and GIP (leans one way) | Mid-sized study (469 people) | 48 weeks | 22.5% more than a dummy shot | Big studies starting |
| Eloralintide 9 mg | Amylin only | Mid-sized study (263 people) | 48 weeks | 20.1% (0.4% on a dummy shot) | Big final-stage studies |
| MariTide | Switches GLP-1 on, blocks GIP, monthly | Mid-sized study (NEJM) | 52 weeks | 12.3 to 16.2% counting everyone who started; up to about 20% for people who kept taking it | Big final-stage studies |
| Amycretin | GLP-1 plus amylin in one molecule | Mid-sized study | 36 weeks | 14.6% | Big final-stage studies (AMAZE) |
| Aleniglipron 180 mg | GLP-1 (small-molecule pill) | ACCESS II (mid-sized study) | 44 weeks | 16.3% more than a dummy pill | Big studies starting |
Does retatrutide burn fat or muscle?
Direct answer
Like every drug in this family, retatrutide takes off both fat and lean mass, with fat making up most of the loss. Its glucagon effect makes the body burn more energy and clear more liver fat, which is why the three-hormone drugs reach higher totals. The industry's answer is add-on drugs that protect muscle. Apitegromab protected 55 percent of lean mass on tirzepatide, and with bimagrumab plus semaglutide, 93 percent of the weight lost was fat.
Profiles: apitegromab, bimagrumab, trevogrumab, enobosarm.
Which GLP-1 can be taken orally?
Direct answer
In the US, as of September 2026, there are three approved pills. Rybelsus (semaglutide pill for diabetes). The Wegovy pill (semaglutide 25 mg for weight, December 2025). And Foundayo (orforglipron, April 2026), the first small-molecule GLP-1 pill with no food or water rules. Aleniglipron, elecoglipron and HRS-7535 are in big final-stage studies. Danuglipron was dropped.
Peptide pills like semaglutide need an added ingredient to get absorbed, and an empty stomach. Small-molecule pills like orforglipron don't. That is the practical difference. So far, the shots take off far more weight than the pills. See the GLP-1 pill profiles.
What is stronger than retatrutide?
Direct answer
Nothing with results from a big final-stage study. Enicepatide's 22.5 percent at 48 weeks and eloralintide's 20.1 percent come from mid-sized studies that ran for less time. Mixing drugs (a GLP-1 drug plus an antibody that protects muscle, or plus amylin) is where the field is heading, but no mix has reported more total weight loss than retatrutide alone.
Side effects worth knowing in 2026
- Stomach problems (nausea, vomiting, constipation) come with every GLP-1 drug and get worse at higher doses.
- Skin tingling or a changed feeling in the skin (dysesthesia) showed up in 12.5 percent of people on 12 mg retatrutide in TRIUMPH-1 (20.9 percent in TRIUMPH-4). It showed up in about 23 percent on Wegovy HD 7.2 mg, against about 6 percent on a dummy shot. Nobody knows yet why it happens.
- Every drug in this family takes off some lean mass. That is why muscle-protecting add-ons are being tested.
- Orforglipron's label carries a boxed warning about thyroid tumors, and so do the GLP-1 shots.
For turning a dose into syringe units on any of the shots, the calculator handles mg and mcg and shows the mark on your syringe. The half-life reference explains why some are weekly and one is monthly.
Frequently asked questions
Can I go from tirzepatide to retatrutide?
Retatrutide is not approved anywhere, so outside a study there is no real way to switch. Products sold online under the name have not been checked.
Can you take retatrutide and tirzepatide at the same time?
No study has tested it. Both work on the GLP-1 and GIP signals, so taking both mostly adds dose and side effects, not anything new.
When will retatrutide be available?
Lilly has said it expects to ask for approval in late 2026, after the rest of the TRIUMPH studies. A decision would come in 2027 at the earliest.
What is the strongest GLP-1 for weight loss?
Among approved shots, tirzepatide has the biggest reported weight loss. Among drugs with big final-stage study results, retatrutide does. Among pills, the Wegovy pill (13.6 percent) is ahead of orforglipron (11.2 percent), counting everyone who started. These come from separate studies, not head-to-head tests.
Compound profiles mentioned
- RetatrutideStrong. At least two finished studies in people, and at least 1,000 people who took it. 5 completed trials, 1,345 people given it.Metabolic
- TirzepatideStrong. At least two finished studies in people, and at least 1,000 people who took it. 9 completed trials, 22,802 people given it.Metabolic
- SemaglutideStrong. At least two finished studies in people, and at least 1,000 people who took it. 12 completed trials, 42,363 people given it.Metabolic
- CagriSemaStrong. At least two finished studies in people, and at least 1,000 people who took it. 3 completed trials, 4,954 people given it.Metabolic
- MariTideLimited. People have taken it in a published study, but fewer than 100 of them. 1 completed trial, none stating how many people.Metabolic
- AmycretinModerate. At least one finished study in people, and at least 100 people who took it. 1 completed trial, 125 people given it.Metabolic
- OrforglipronStrong. At least two finished studies in people, and at least 1,000 people who took it. 8 completed trials, 17,383 people given it.Metabolic
- AleniglipronLimited. People have taken it in a published study, but fewer than 100 of them. 1 completed trial, none stating how many people.Metabolic
- EloralintideLimited. People have taken it in a published study, but fewer than 100 of them. 1 completed trial, none stating how many people.Metabolic
- EnicepatideLimited. People have taken it in a published study, but fewer than 100 of them. 2 completed trials, none stating how many people.Metabolic
Sources
- Study in people2026
Lilly's triple agonist retatrutide delivered powerful weight loss in pivotal Phase 3 obesity trial (TRIUMPH-1)
28.3 percent weight loss at 80 weeks; 45 percent lost 30 percent or more.
Eli Lilly - Study in people2022
Tirzepatide once weekly for the treatment of obesity (SURMOUNT-1)
About 21 percent weight loss at 72 weeks on 15 mg.
New England Journal of Medicine - Study in people2021
Once-weekly semaglutide in adults with overweight or obesity (STEP 1)
About 15 percent weight loss at 68 weeks.
New England Journal of Medicine - Study in people2025
Coadministered cagrilintide and semaglutide in adults with overweight or obesity
REDEFINE 1: 20.4 percent weight loss counting everyone who started, and 22.7 percent for people who kept taking it, at 68 weeks. 3.0 percent on a dummy shot.
New England Journal of Medicine - Study in people2025
Orforglipron in obesity (ATTAIN-1)
11.2 percent counting everyone who started, and 12.4 percent for people who kept taking it, at 72 weeks.
New England Journal of Medicine - Study in people2026
FDA approves Foundayo (orforglipron)
Approved April 1, 2026.
Eli Lilly - Study in people2025
Maridebart cafraglutide in obesity (Phase 2)
12.3 to 16.2 percent counting everyone who started, up to about 20 percent for people who kept taking it, at 52 weeks on monthly shots.
New England Journal of Medicine - Study in people2026
Aleniglipron Phase 2 (ACCESS II)
16.3 percent more weight loss than a dummy pill at 44 weeks.
Nature Medicine - Review of studies2025
Retatrutide versus tirzepatide: comparative analysis
Compares separate studies; no head-to-head study exists.
PubMed Central PMC12544991
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Educational use only. This database summarizes published research and is not medical advice. Where a dose appears it is a record of what a trial or clinic ran, or what people describe doing, with its source attached. Nothing here is a recommendation for personal use. Sellers named on the price pages are ranked by certificate tier, then price, and any affiliate income is disclosed there. Naming a seller is not a recommendation to buy or use anything.