Cagrilintide vs Retatrutide: Amylin Analog vs Triple Agonist, Compared

Cagrilintide and retatrutide come at weight research from opposite ends. Cagrilintide is a long-acting copy of amylin, a hormone that signals fullness, and it works through one system. Retatrutide is a single molecule that switches on three hormone receptors at once: GLP-1, GIP and glucagon.

People search them together to see how a focused, well-tolerated mechanism compares with the broadest molecule in the field. This guide covers their targets, how long they last, the trial numbers through 2026, and why cagrilintide is usually studied with semaglutide (as CagriSema) rather than against retatrutide. Everything below is for laboratory and research use only.

Key Takeaways

• Cagrilintide (CAS 1415456-99-3) is a long-acting amylin analog. It switches on the amylin receptors (AMY1R to AMY3R) and the calcitonin receptor, which signal fullness in research models.
• Retatrutide (CAS 2381089-83-2) is a triple agonist. It switches on GLP-1, GIP and glucagon receptors together, a much broader mechanism.
• Trial size of effect: in its Phase 3 TRIUMPH-1 trial, retatrutide 12 mg cut body weight by 25.0% at 80 weeks, against 3.9% on placebo. Cagrilintide alone reached 10.8% at 26 weeks in its Phase 2 trial.
• Cagrilintide's best data is as a pair. With semaglutide (CagriSema), it cut body weight by 20.4% at 68 weeks in REDEFINE 1, against 3.0% on placebo.
• Both are once-weekly molecules because they last for days: cagrilintide about 159 to 195 hours, retatrutide about 6 days.
• No human trial has combined cagrilintide with retatrutide. The first animal study did in 2026: in obese rats, the pair cut more weight than either alone.

Cagrilintide: The Long-Acting Amylin Analog

Cagrilintide, called AM833 in early papers, is a long-acting version of amylin. The pancreas releases amylin together with insulin after a meal, and its job is to signal fullness. Cagrilintide was built from the amylin chain so it would last far longer in the blood.

It is a 37-amino-acid peptide, close to pramlintide, with a few amino acids swapped and a fatty acid chain (C20, attached through a gamma-glutamic acid link) on its front end. That fatty acid makes it stick to albumin, the main protein in blood, which stretches its half-life from about 15 minutes for natural amylin to several days. In research it acts on all three amylin receptors (AMY1R, AMY2R and AMY3R) and on the calcitonin receptor, in the brain areas that control appetite.

Its half-life is about 159 to 195 hours, which is why published studies give it once a week (Enebo, 2021). In a Phase 2 trial, once-weekly cagrilintide alone cut body weight by up to 10.8% over 26 weeks (Lau, 2021). Labs studying fullness signals, how fast the stomach empties, or amylin biology often choose it because it isolates one mechanism cleanly. You can review specifications for the cagrilintide research peptide on the product page, including third-party HPLC data.

Retatrutide: The Triple Receptor Agonist

Retatrutide is a different kind of molecule. One synthetic peptide switches on three receptors: GLP-1, GIP and glucagon. GLP-1 and GIP are linked to appetite and blood sugar control in research models, and the glucagon part is linked to burning more energy. In trials the three together beat what any one pathway did alone.

In the Phase 2 trial, retatrutide 12 mg cut body weight by up to 24.2% at 48 weeks in adults without diabetes (Jastreboff, 2023). The Phase 3 program has since gone further. In TRIUMPH-1 (2,339 adults with obesity, no diabetes), weight fell 17.6%, 23.7% and 25.0% at the 4, 9 and 12 mg doses over 80 weeks, against 3.9% on placebo (Jastreboff, 2026). Among people who stayed on 12 mg, the loss was 28.3%. Lilly plans to file for FDA approval in early 2027.

Liver fat dropped sharply too: in a Phase 2a study, mean liver fat fell by more than 80% at the higher doses (Sanyal, 2024). The most common side effects were gastrointestinal, as with the whole GLP-1 class.

For more on the triple-agonist mechanism, see the retatrutide kit and the retatrutide vs tirzepatide vs semaglutide comparison.

Cagrilintide vs Retatrutide: Side-by-Side Comparison

The two molecules are not built to do the same job, and that is the most important point.

Retatrutide is the broader molecule, both in how it works and in the size of the effect. Cagrilintide is narrower and is usually used as a partner to a GLP-1 drug rather than on its own.

Why Cagrilintide Is Studied With Semaglutide, Not Retatrutide

People often ask why nobody tests cagrilintide directly against retatrutide. The answer is in how they work. Cagrilintide's amylin signal adds to a GLP-1 signal instead of repeating it, so pairing cagrilintide with a GLP-1 drug engages two separate fullness pathways at once.

That is the whole idea behind CagriSema, cagrilintide plus semaglutide. In REDEFINE 1 (3,417 adults with overweight or obesity), it cut body weight by 20.4% at 68 weeks, against 3.0% on placebo (Garvey, 2025). In people who stayed on treatment the figure was about 22.7%. A sister trial in people with type 2 diabetes, REDEFINE 2, also succeeded (Davies, 2025). The pairing works because the two mechanisms do not overlap.

Retatrutide already packs several pathways into one molecule, and no clinical program has combined it with cagrilintide. The first animal study has: in obese rats, cagrilintide plus retatrutide cut body weight and food intake more than either one alone, and more than cagrilintide paired with semaglutide or tirzepatide at matched doses (Petersen, 2026). The extra weight loss was more than eating less could explain. For more on the amylin side, see the cagrilintide research guide, the semaglutide kit and the ready-made cagrilintide and semaglutide blend.

Half-Life, Stability, and Lab Handling

Both peptides arrive as freeze-dried powders that are mixed before use. Both last a long time in the body for the same reason: a fatty acid chain that binds albumin. So they are handled the same way. Once mixed, keep them cold and avoid freezing and thawing them again and again.

If your lab is new to either compound, how to reconstitute research peptides and the peptide storage and stability guide cover the basics: choosing bacteriostatic water, swirling instead of shaking, splitting into portions, and how long to keep them in the fridge. Purity verification matters too. Every batch we supply ships with a published certificate of analysis, and you can learn what to look for in our how to verify research peptide purity with a COA guide.

Choosing Between Them for Research

The research question decides. Studies of amylin receptors, fullness signals or stomach emptying point to cagrilintide, because it engages one mechanism cleanly. Studies of several metabolic pathways at once, energy use or liver fat point to retatrutide, because of its triple action.

Labs testing whether two mechanisms add up tend to pair cagrilintide with a GLP-1 drug rather than compare it with retatrutide, because that is where the published evidence is. Neither molecule wins everywhere. The comparison is about matching the tool to the experiment.

Sourcing Cagrilintide and Retatrutide for Research

Material quality is the variable most under your control. Lyze Labs supplies both compounds at 99 percent or higher purity, third-party HPLC tested, with a published COA for every batch so you can confirm identity and concentration before work begins. Researchers in 150+ countries order from us, with 10,000+ orders shipped.

Each kit is ten vials from one batch. Orders paid before the daily batch closes are processed that day. Shipping is free and tracked, most orders arrive in 7 to 14 days, and delivery is guaranteed. You can pay by Visa, Mastercard, Amex, PayPal, Apple Pay, Google Pay, bank transfer, local wallets and bank apps in your region, or crypto (USDT, USDC, BTC).

Frequently Asked Questions

What is the main difference between cagrilintide vs retatrutide?

Cagrilintide is an amylin analog: it switches on amylin and calcitonin receptors to signal fullness. Retatrutide is a triple agonist: it switches on GLP-1, GIP and glucagon receptors at the same time. Cagrilintide isolates one pathway, retatrutide engages three, and they answer different research questions.

Which has shown greater weight reduction in studies, cagrilintide or retatrutide?

Retatrutide, by a wide margin as a single drug. In the Phase 3 TRIUMPH-1 trial, retatrutide 12 mg cut body weight by 25.0% at 80 weeks, while cagrilintide alone reached 10.8% at 26 weeks in its Phase 2 trial. Cagrilintide's strongest results come from its pairing with semaglutide, which reached 20.4% at 68 weeks.

Why is cagrilintide combined with semaglutide as CagriSema?

Cagrilintide's amylin signal adds to semaglutide's GLP-1 signal instead of repeating it, so the pair engages two separate fullness pathways. In the REDEFINE 1 trial, CagriSema cut body weight by 20.4% at 68 weeks against 3.0% on placebo. That is why cagrilintide is studied with semaglutide rather than against retatrutide.

Can cagrilintide and retatrutide be combined in research?

Not yet in people: no clinical program has combined them. The first animal study, in obese rats (2026), found the pair cut more weight than either alone and more than cagrilintide with semaglutide or tirzepatide. Combination work is new ground, which makes it an open research question.

What are the half-lives of cagrilintide and retatrutide?

Cagrilintide's half-life is about 159 to 195 hours, and retatrutide's is about 6 days. Both are given once a week in published studies, because a fatty acid chain that binds albumin keeps them in the blood. Both arrive as freeze-dried powders that are mixed before use.

How can I verify the purity of cagrilintide or retatrutide before research?

Request the third-party HPLC certificate of analysis for the specific batch, which confirms purity at 99 percent or higher along with identity and concentration. Lyze Labs publishes a COA for every batch. Our guide on verifying research peptide purity explains how to read the chromatogram, mass spec data, and batch identifiers so you can confirm material quality before any work begins.

Order Cagrilintide for Your Research

Whether your study needs a focused amylin analog or you are mapping the wider metabolic field, start with material you can check. View specifications and the published COA on the cagrilintide product page. Free discreet worldwide shipping, 99 percent or higher purity, and a COA in every order, with 10,000+ orders shipped to researchers in 150+ countries.

Studies Cited

• Jastreboff AM, et al. (2023). Triple-hormone-receptor agonist retatrutide for obesity: a phase 2 trial. New England Journal of Medicine.
• Jastreboff AM, et al. (2026). Retatrutide, a triple hormone receptor agonist, for treatment of obesity. New England Journal of Medicine.
• Sanyal AJ, et al. (2024). Triple hormone receptor agonist retatrutide for metabolic dysfunction-associated steatotic liver disease: a randomized phase 2a trial. Nature Medicine.
• Garvey WT, et al. (2025). Coadministered cagrilintide and semaglutide in adults with overweight or obesity. New England Journal of Medicine.
• Davies MJ, et al. (2025). Cagrilintide-semaglutide in adults with overweight or obesity and type 2 diabetes. New England Journal of Medicine.
• Lau DCW, et al. (2021). Once-weekly cagrilintide for weight management in people with overweight and obesity: a dose-finding phase 2 trial. The Lancet.
• Petersen J, et al. (2026). Cagrilintide and retatrutide combination therapy enhances weight loss and metabolic outcomes in obese male rats. Nature Metabolism.
• Enebo LB, et al. (2021). Safety, tolerability, pharmacokinetics, and pharmacodynamics of cagrilintide with semaglutide 2.4 mg: a phase 1b trial. The Lancet.