Cagrilintide: The Amylin Analog That Only Matters in Combination

Cagrilintide's headline number is 20.4% weight loss. That result belongs to CagriSema, the two-drug combination. Cagrilintide on its own produced 10.8% over 26 weeks — a real result, less than semaglutide achieves, and roughly half what tirzepatide achieves.

Novo Nordisk filed CagriSema for FDA approval in December 2025 on the strength of that combination, and cagrilintide monotherapy is not being developed as a product at all. The full combination story is in CagriSema: the science behind the cagrilintide + semaglutide combination; this article is about the amylin half on its own, and sits in the weight loss and metabolic peptides category.

What is cagrilintide, and how does it differ from semaglutide?

Cagrilintide is a long-acting amylin analogue — CAS 1415456-99-3, molecular weight 4,409 g/mol, a lipidated peptide carrying a cyclic disulfide, with a half-life near seven days that supports once-weekly dosing. Novo Nordisk developed it under the codes NN0174-0833 and AM833. It is not a GLP-1 drug. Amylin and GLP-1 bind different receptors, which is why semaglutide, a 4,113.6 Da GLP-1 agonist, became cagrilintide's partner rather than its competitor. It has never been approved anywhere.

Amylin is a hormone co-secreted with insulin by pancreatic β-cells. It signals satiety through the brainstem and slows gastric emptying. Cagrilintide is a stabilised, long-acting version of that signal, and the compound page is cagrilintide.

The mechanistic point that matters is that this is not a GLP-1 pathway. That distinctness is the entire rationale for putting the two together.

Why does cagrilintide only become interesting alongside a GLP-1 agonist?

Cagrilintide recruits a satiety pathway that GLP-1 agonists largely do not reach. Amylin is co-secreted with insulin by pancreatic β-cells and signals fullness through the brainstem — the area postrema and nucleus tractus solitarius — while slowing gastric emptying. Preclinical work in EBioMedicine (2025) attributes cagrilintide's weight-lowering effect to brain amylin receptors 1 and 3, animal data rather than human. A pharmacology review describes amylin acting on both homeostatic and hedonic regions.

Those two words carry the argument. A pharmacology review in Cardiology in Review describes amylin's satiating effect operating on the homeostatic system, which governs energy need, and the hedonic system, which governs food reward. GLP-1 agonists work largely on the homeostatic side.

Recruiting a second, partly independent satiety circuit is therefore something a higher GLP-1 dose cannot do. It is also why "add cagrilintide to semaglutide" turned out to be a better idea than "develop cagrilintide".

How much weight loss does cagrilintide produce on its own?

Cagrilintide monotherapy produced 10.8% weight loss — 11.5 kg — at 4.5 mg once weekly over 26 weeks in its Phase 2 randomised trial, against 9.0% for liraglutide (p=0.03) and 3.0% for placebo. That is a genuine result and a modest one: semaglutide reaches 14.9% at 68 weeks. Within a single trial, Frias 2023 measured cagrilintide alone at 8.1% against 15.6% for the combination in type 2 diabetes.

The Frias 2023 row is the cleanest demonstration of the combination effect available, because all three comparisons sit inside one trial at one time point: 8.1% for cagrilintide, 5.1% for semaglutide, 15.6% for the two together. Neither component predicts the pair.

Set against the approved options, the monotherapy number is unremarkable. Full comparator detail is in semaglutide science, weight loss and safety profile.

What happened when CagriSema was tested head-to-head against tirzepatide?

CagriSema lost. REDEFINE 4 randomised patients with obesity to CagriSema or tirzepatide 15 mg for 84 weeks and reported 23.0% versus 25.5% weight loss in February 2026 — a failure to demonstrate noninferiority against the market leader. Twenty-three percent is a substantial clinical result by any historical standard. It was not, however, the result the trial was designed to produce, and summaries quoting only REDEFINE 1 omit it.

This was the first time Novo Nordisk's combination met Eli Lilly's leading agent inside the same trial, under the same protocol, in the same population. Cross-trial comparison stops being necessary at that point, which is exactly why the result carries so much weight.

The mechanism detail on the comparator is in tirzepatide science: the dual GIP/GLP-1 mechanism. The honest reading of the table is that CagriSema is a strong drug that arrived into a field where the bar had already moved.

Is cagrilintide approved anywhere?

No. Cagrilintide is not approved by the FDA or the EMA, and neither is CagriSema. Novo Nordisk filed the CagriSema new drug application in December 2025 with a decision anticipated in late 2026; standalone cagrilintide remains investigational and is not being developed as a product. Cagrilintide is also not named on the WADA Prohibited List (2026 List, checked August 2026). Any vendor claiming FDA approval is wrong, and that error is itself diagnostic.

False approval claims for this compound are already circulating, which makes the status worth stating flatly rather than hedging. Treat "FDA-approved cagrilintide" the way you would treat a wrong CAS number: not as a marketing exaggeration but as evidence that the seller does not know the product. The wider picture is in our FDA peptide regulation timeline.

Which cagrilintide claims survive contact with the evidence?

One of eight. Of the eight claims most often attached to cagrilintide, only the non-GLP-1 mechanism is supported outright, and that support is preclinical. Two are false — that it beats tirzepatide, and that it is FDA approved. One is true only of the combination, one is overstated, one has no data at all, one rests on unpublished company topline figures, and one traces to no cagrilintide publication whatsoever.

The lean-mass row is the one worth pausing on. It is not a weak finding or a contested finding — there is no published cagrilintide body-composition trial to weigh at all, and a claim with no study behind it should not be graded as "promising".

What side effects did the cagrilintide trials report?

Gastrointestinal events — nausea, vomiting and constipation — were the most frequently reported adverse events across both the cagrilintide monotherapy and CagriSema combination programmes, mostly mild to moderate and concentrated during dose escalation. No citable incidence rate exists: published rates vary by trial, dose and estimand, and the specific percentages circulating for cagrilintide do not trace to any publication. Hypoglycaemia risk rises when either drug is combined with insulin or sulfonylureas.

That profile is mechanistically unsurprising. Amylin and GLP-1 agonism both slow gastric emptying and both act on brainstem circuits that also mediate nausea, so the side-effect pattern and the efficacy pattern come from the same place.

Two further cautions attach to the combination rather than to cagrilintide itself: the medullary thyroid carcinoma and MEN 2 contraindications that come with the GLP-1 component. Long-term independent safety surveillance does not yet exist for either product, because neither is marketed. The REDEFINE 1 paper carries the combination's safety tables, and our peptide side effects hub covers the class.

What dose was cagrilintide trialled at, and can CagriSema be rebuilt from two vials?

No approved or validated cagrilintide dosing protocol exists, because no product containing cagrilintide has been approved. The Phase 2 trial used a ladder from 0.3 to 4.5 mg once weekly, reached by stepwise escalation to limit gastrointestinal effects. CagriSema is a fixed-dose combination: the ratio is set by the manufacturer, not chosen by the user. Reproducing it from two separately sourced research vials is not the intervention that was trialled.

The escalation is not optional decoration. The Phase 2 ladder existed because gastrointestinal tolerability is dose-dependent, and the trial results attach to the ladder, not just to the top dose.

The fixed-dose point has the sharper practical consequence. A combination is defined by its ratio, and in CagriSema that ratio is a manufacturing decision embedded in the product. Two vials bought separately, reconstituted separately and drawn separately reproduce neither the ratio nor the trial. For the arithmetic on any single vial, use the peptide dosing calculator alongside the reconstitution calculator.

How do you verify that a vial labelled cagrilintide really is cagrilintide?

Mass spectrometry is the only test that establishes identity. A vial of cagrilintide should return a mass near 4,409 Da, comfortably separable on a trace from semaglutide at 4,113.6 Da — which matters most when a product is sold as a combination. The label should carry CAS 1415456-99-3. HPLC purity measures how much of a single species is present, not which species, and net peptide content is a third, separate measurement.

Because cagrilintide's mass sits well clear of semaglutide's, identity testing here is genuinely straightforward — which is unusual, and worth exploiting if you are evaluating anything sold as a two-component product. See mass spectrometry for peptides, and note that purity and quantity are separate axes: why 10 mg isn't 10 mg.

Peptigrity tracks 530 shops and 11,852 independent lab tests across 118 peptides, with 1,283 community reviews (verified August 2026). Trust scores weight community reviews and independently verified HPLC purity equally, at 50% each, with no financial relationship influencing the ranking — the method is published at how we calculate trust scores. Per-compound purity and test counts are read live from the Purity Index, independent results from the lab test database, and per-milligram offers with shops-in-stock, median and lowest price from cagrilintide price data. Those figures exclude shipping, taxes and customs, coupon codes, bulk tiers, multi-vial kits and account-gated pricing.

What is still unknown about cagrilintide?

Six substantial questions remain open, and the largest is body composition: no published cagrilintide body-composition trial exists, which leaves the widely repeated lean-mass claim with nothing behind it. No dedicated cardiovascular outcome trial has reported. The longest published follow-up is REDEFINE 4 at 84 weeks. Standalone glycaemic effects were never published in a dedicated trial, and monotherapy development was effectively abandoned in favour of the combination.

The trial that would settle this. One study would close the largest gap, and it is a body-composition trial rather than another weight-loss trial.

Until that trial exists, "preserves lean mass" should be read as an untested hypothesis rather than a weak result. Discount the claim entirely if a vendor cites a study number for it, because none exists.

Frequently Asked Questions

Is cagrilintide approved?

No. Novo Nordisk filed the CagriSema NDA with the FDA in December 2025 and a decision is anticipated in late 2026. Standalone cagrilintide is not being developed as a product, and neither compound is approved by the FDA or EMA as of August 2026.

Is cagrilintide better than semaglutide?

Alone, no — 10.8% at 26 weeks versus semaglutide's 14.9% at 68 weeks. Combined with semaglutide, the pair substantially outperforms semaglutide alone, reaching 20.4% at 68 weeks in REDEFINE 1. The improvement comes from the combination, not from cagrilintide's own potency.

Did CagriSema beat tirzepatide?

No. In REDEFINE 4, CagriSema produced 23.0% against tirzepatide's 25.5% over 84 weeks and failed to demonstrate noninferiority. That is the head-to-head result, reported in February 2026, and it removes the need for cross-trial guesswork.

Is cagrilintide a GLP-1 drug?

No. Cagrilintide is an amylin analogue acting on amylin receptors, a different pathway from GLP-1. That distinctness is precisely what makes the combination with a GLP-1 agonist work, since the two recruit partly separate satiety circuits.

Can I combine research-grade cagrilintide and semaglutide myself?

CagriSema is a fixed-dose combination with a manufacturer-set ratio, developed and trialled as a single product. Combining two separately sourced, unverified research vials is not the intervention that was studied, and the ratio is doing real work in the trial results.

How do I know my vial is really cagrilintide?

Mass spectrometry showing a mass near 4,409 Da, and a CAS of 1415456-99-3 on the label. HPLC purity alone cannot confirm identity — it measures how much of one species is present, not which species that is.

Browse the weight loss and metabolic peptides category, or our complete peptide guide with 118 compounds (verified August 2026). For reconstitution and per-injection volume, use the peptide dosing calculator alongside the reconstitution calculator. Compare shops through independent lab tests and community-verified shop reviews.

This article is for educational and informational purposes only and does not constitute medical advice. Peptides discussed may be investigational compounds not approved by the FDA (or equivalent regulators in your jurisdiction) for human use. Always consult a qualified healthcare provider before using any peptide or research compound. Peptigrity is an independent review platform and does not sell, endorse, or recommend specific products or vendors.