Metabolic / Published Sep 8, 2026 / Reviewed Sep 27, 2026 / 9 min read
Cagrilintide: The Amylin Half of CagriSema, and Why People Search 'Cagrilintide with Retatrutide'
Written by Aaron CuhaReviewed Sep 27, 2026
What cagrilintide is, how much weight people lost on CagriSema in studies of more than 5,000 people, what it did alone, where the FDA filing stands, how three rival amylin drugs compare, and why nobody has ever tested it with retatrutide. Plain English, every study linked.
Key takeaways
- Cagrilintide is a weekly shot from Novo Nordisk that copies amylin, a hormone your pancreas makes along with insulin. It is not approved anywhere on its own. CagriSema, a single shot that mixes it with semaglutide, was sent to the FDA on December 18, 2025 and is waiting for a decision.
- In the biggest study, 3,417 people without diabetes lost 20.4% of their body weight on CagriSema over 68 weeks, against 3.0% on a dummy shot. In 1,206 people with type 2 diabetes, they lost 13.7%, against 3.4%.
- Head to head, CagriSema lost to tirzepatide. In 809 people over 84 weeks, people on CagriSema lost 23.0% and people on tirzepatide lost 25.5%.
- On its own, cagrilintide took off 6.0% to 10.8% of body weight over 26 weeks in 706 people, against 3.0% on a dummy shot and 9.0% on liraglutide.
- Three rival amylin drugs are coming: eloralintide from Lilly (20.1% at 48 weeks), petrelintide from Zealand and Roche (10.7% at 42 weeks) and AZD6234 from AstraZeneca (results not yet published).
- Nobody has ever tested cagrilintide with retatrutide. They belong to rival companies, retatrutide is not approved either, and the tirzepatide result shows that adding amylin does not always win.
What is cagrilintide?
Direct answer
Cagrilintide is a long-lasting, lab-made copy of amylin, a hormone your pancreas releases along with insulin. No country has approved it. Its only big use so far is inside CagriSema, a weekly shot that mixes it with semaglutide 2.4 mg. Novo Nordisk sent CagriSema to the FDA on December 18, 2025, after two 68-week studies.
Most weight-loss shots people know copy gut hormones called GLP-1 and GIP. Cagrilintide is the first of a different family to reach a regulator. It copies amylin, which your pancreas releases after a meal. Amylin works mostly in the brain. It makes you feel full sooner, slows how fast your stomach empties and lowers a hormone that raises blood sugar (Diabetes Therapy review, 2025). An older amylin drug, pramlintide, is approved for people with diabetes who use insulin. It proved the idea works, but it had to be injected with every meal. Cagrilintide carries a fatty chain that makes one shot last a week. Profiles: cagrilintide, CagriSema.
What happened to people on CagriSema?
Direct answer
In 3,417 people without diabetes, CagriSema took off 20.4% of body weight over 68 weeks, against 3.0% on a dummy shot. That rose to 22.7% for people who kept taking it. In 1,206 people with type 2 diabetes, it took off 13.7%, against 3.4%. In 809 people over 84 weeks, it took off 23.0%, against 25.5% on tirzepatide.
| Study | Who | How long | Weight lost on CagriSema | Compared with | Worth knowing |
|---|---|---|---|---|---|
| REDEFINE 1 (NEJM, June 2025) | 3,417 adults with overweight or obesity, no diabetes | 68 weeks | 20.4% counting everyone who started; 22.7% for people who kept taking it | 3.0% on a dummy shot. Groups of 302 each also took semaglutide alone or cagrilintide alone. | Stomach problems in 79.6%, against 39.9% on the dummy. 6% quit because of side effects, against 3.7%. |
| REDEFINE 2 (NEJM, June 2025) | 1,206 adults with obesity and type 2 diabetes | 68 weeks | 13.7% counting everyone who started; 15.7% for people who kept taking it | 3.4% on a dummy shot | Stomach problems in 72.5%, against 34.4% on the dummy |
| REDEFINE 4 (announced February 23, 2026) | 809 adults with obesity and another health problem | 84 weeks | 23.0% for people who kept taking it; 20.2% counting everyone | Tirzepatide 15 mg: 25.5% and 23.6% | Everyone knew which drug they were on. CagriSema did not match tirzepatide, which was the goal. |
Novo had hinted at 25% for REDEFINE 1, so the 20.4% result let investors down. Even so, among the big final-stage studies it sits second only to retatrutide, which reported 28.3% at 80 weeks in TRIUMPH-1 (NEJM, REDEFINE 1; NEJM, REDEFINE 2). REDEFINE 4 matters most for understanding amylin. Adding cagrilintide to semaglutide did not match tirzepatide on its own over 84 weeks (Novo Nordisk, February 2026). Novo's answer is a stronger CagriSema, with cagrilintide 2.4 mg and semaglutide 7.2 mg. A large final-stage study of it starts in the second half of 2026.
What did cagrilintide do on its own?
Direct answer
In a 26-week study of 706 people with overweight or obesity at 57 sites (Lancet, 2021), a weekly cagrilintide shot of 0.3 to 4.5 mg took off 6.0% to 10.8% of body weight. People on a dummy shot lost 3.0%. The top dose beat liraglutide 3.0 mg, 10.8% against 9.0%. Four in 100 quit because of side effects.
Stomach problems hit 41% to 63% of people on cagrilintide, against 32% on the dummy shot (Lancet, 2021). This was a mid-sized study in people. It showed a drug that is not a GLP-1 could take off about as much weight as one. That is the whole idea behind CagriSema: two different routes that might add up. Novo never ran a big study of cagrilintide alone for weight loss, so the results for it alone stop at 26 weeks.
Is CagriSema approved yet?
Direct answer
No. Novo Nordisk asked the FDA to approve it on December 18, 2025, for long-term weight control in adults with obesity, or with overweight plus another health problem. Novo expected a review during 2026. As of September 2026, the FDA has not announced a decision. Cagrilintide on its own has not been sent for approval anywhere.
The filing rests on REDEFINE 1 and 2 (Novo Nordisk, December 2025). A normal review would put a decision around late 2026. Until then, any vial labeled cagrilintide sold online is unapproved. Nobody has checked what is in it, how pure it is or how much is there. See how to read a lab certificate for why that matters, and the FDA's 2026 peptide status for the legal side.
How do the other amylin drugs compare?
Direct answer
Eloralintide from Lilly took off 9.5% to 20.1% of body weight at 48 weeks in 263 people (Lancet, November 2025). It is now in large final-stage studies, alone and with tirzepatide. Petrelintide from Roche took off 10.7% at 42 weeks in 493 people, and people quit it no more often than a dummy shot. AstraZeneca's AZD6234 has big studies planned but no published numbers.
| Drug | Company | Best result reported | Where it stands | Size of the evidence |
|---|---|---|---|---|
| Cagrilintide | Novo Nordisk | 20.4% at 68 weeks inside CagriSema (REDEFINE 1, 3,417 people); 10.8% at 26 weeks alone (706 people) | CagriSema is waiting on the FDA | Large final-stage studies in people |
| Eloralintide | Eli Lilly | 20.1% at 48 weeks on 9 mg (263 people), against 0.4% on a dummy shot | Large final-stage studies, alone and with tirzepatide | Mid-sized study in people |
| Petrelintide | Zealand Pharma and Roche | 10.7% at 42 weeks (ZUPREME-1, 493 people), against 1.7%; 4.8% quit, against 4.9% on a dummy | Large final-stage study planned for the second half of 2026 | Mid-sized study in people |
| AZD6234 | AstraZeneca | Not published. A study of 262 people on it alone finished in December 2025. | A final-stage study of 2,500 people is set to start August 2026 | Mid-sized study in people, results not shared |
The selling point for amylin drugs is that people may feel less sick on them, not just that they work. In ZUPREME-1, vomiting was less common on petrelintide than on the dummy shot (Roche, March 2026). On eloralintide, the two lowest doses caused about as many side effects as the dummy shot, though nausea reached 64% at the highest doses (Lancet, 2025). The only public sign of how AstraZeneca's mid-sized study went is that it listed a big final-stage study (ClinicalTrials.gov NCT07784725).
Why do people search 'cagrilintide with retatrutide'?
Direct answer
Because it sounds like CagriSema with a stronger partner. Retatrutide reported 28.3% weight loss at 80 weeks in 2,339 people (TRIUMPH-1, May 2026). But no study has ever put the two together. Novo Nordisk owns cagrilintide and Eli Lilly owns retatrutide. Neither is approved. And CagriSema already lost to tirzepatide alone.
The thinking is simple addition. Cagrilintide added about 5 points to semaglutide in REDEFINE 1, so why not add it to the strongest drug? There are three problems. First, nobody has tested it. Retatrutide also works on glucagon, a hormone that makes the body burn more energy. Nobody knows how that mixes with amylin's effects on blood sugar and stomach emptying. Second, the companies will not run that study. Lilly is testing its own amylin drug, eloralintide, with tirzepatide instead. Third, the adding-up idea has already failed once. CagriSema, the best-tested amylin mix, lost to tirzepatide in REDEFINE 4. Anything sold online under both names is unchecked product, mixed in a way no ethics board has looked at. For the other side of the comparison, see retatrutide versus tirzepatide.
The bottom line
Cagrilintide showed that amylin can take weight off on its own. Inside CagriSema, it became the first amylin drug sent to the FDA. The studies are big, the weight loss is real, and among the big final-stage studies only retatrutide reported more. The head-to-head against tirzepatide showed where the limit is. There are now four amylin drugs in the race, and eloralintide's 48-week result is the one to watch. Cagrilintide with retatrutide exists only as a search term.
Frequently asked questions
Is cagrilintide the same as CagriSema?
No. Cagrilintide is the amylin copy. CagriSema is cagrilintide 2.4 mg plus semaglutide 2.4 mg in one weekly shot. Only CagriSema has been sent for approval.
How much weight do you lose on cagrilintide?
Inside CagriSema, people lost 20.4% of body weight over 68 weeks in a study of 3,417 people, counting everyone who started. On its own, people lost 6.0% to 10.8% over 26 weeks, depending on the dose, in a 2021 study of 706 people.
When will CagriSema be approved?
Novo Nordisk asked the FDA to approve it on December 18, 2025 and expected a review in 2026. As of September 2026, no decision had been announced.
Can you take cagrilintide with retatrutide?
Nobody has tested the two together. Neither drug is approved, and rival companies own them. There is no information from people on whether the pair is safe or works.
Compound profiles mentioned
- CagrilintideStrong. At least two finished studies in people, and at least 1,000 people who took it. 5 completed trials, 5,752 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
- EloralintideLimited. People have taken it in a published study, but fewer than 100 of them. 1 completed trial, none stating how many people.Metabolic
- PetrelintideModerate. At least one finished study in people, and at least 100 people who took it. 1 completed trial, 493 people given it.Metabolic
- AZD6234Limited. People have taken it in a published study, but fewer than 100 of them. 1 completed trial, none stating how many people.Metabolic
- 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
- 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
- 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
- PramlintideModerate. At least one finished study in people, and at least 100 people who took it. 3 completed trials, 684 people given it.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
Sources
- Study in people2025
Coadministered cagrilintide and semaglutide in adults with overweight or obesity (REDEFINE 1)
3,417 people without diabetes lost 20.4% of body weight at 68 weeks on CagriSema, against 3.0% on a dummy shot, counting everyone who started.
New England Journal of Medicine - Study in people2025
Cagrilintide and semaglutide in adults with overweight or obesity and type 2 diabetes (REDEFINE 2)
1,206 people with type 2 diabetes lost 13.7% at 68 weeks, against 3.4% on a dummy shot.
New England Journal of Medicine - Study in people2026
CagriSema demonstrated 23 percent weight loss in an open-label head-to-head REDEFINE 4 trial in people with obesity, the primary endpoint was not achieved
809 people over 84 weeks: 23.0% on CagriSema against 25.5% on tirzepatide. CagriSema did not match tirzepatide.
Novo Nordisk company announcement - Study in people2021
Once-weekly cagrilintide for weight management in people with overweight and obesity: a multicentre, randomised, double-blind, placebo-controlled and active-controlled, dose-finding phase 2 trial
706 people: 6.0% to 10.8% weight loss at 26 weeks on cagrilintide alone, against 3.0% on a dummy shot and 9.0% on liraglutide.
The Lancet - Study in people2026
Roche announces positive Phase II results for petrelintide (ZUPREME-1)
493 people: up to 10.7% weight loss at 42 weeks. 4.8% quit, against 4.9% on a dummy shot.
Roche media release - Study in people2025
Eloralintide, a selective amylin receptor agonist for the treatment of obesity: a 48-week phase 2 trial
263 people: 9.5% to 20.1% weight loss at 48 weeks, against 0.4% on a dummy shot.
The Lancet - Study in people2025
Novo Nordisk files for FDA approval of CagriSema, the first once-weekly combination of GLP-1 and amylin analogues for weight management
Sent to the FDA on December 18, 2025; review expected in 2026.
Novo Nordisk company announcement - Study in people2026
A study to evaluate effect of AZD6234 in adult participants with obesity (Phase 3)
Final-stage study of 2,500 people, starting August 2026. Results of the earlier study are not published.
ClinicalTrials.gov NCT07784725 - Review of studies2025
Amylin: from mode of action to future clinical potential in diabetes and obesity
How amylin works in the brain, and the amylin drugs being developed.
Diabetes Therapy
Read next
- Retatrutide vs Tirzepatide vs Semaglutide vs the Pill: The 2026 GLP-1 Field Guide
- FDA Peptide Status in 2026: The Category 2 Removals, the July Votes, and What Actually Changed
- How to Read a Peptide Certificate of Analysis: HPLC Purity, Mass Spec Identity, Endotoxin, and Janoshik Verification
- New Peptides and Longevity Compounds in 2026: What Is Actually New, What Is Newly Legal, and What Is Just New to Vendors
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.