Cagrilintide: What It Is and What It Does

What Cagrilintide is

Cagrilintide is a synthetic, long-acting analogue of amylin, a hormone the pancreas releases with insulin after a meal. A fatty-acid chain lets it bind albumin in the blood, which is what stretches its action to about a week. It is supplied as an analytical-grade reference material for laboratory research.

Where it comes from

Amylin itself was identified in the 1980s, but the natural hormone clears from the blood in minutes, which made it an awkward research tool. Cagrilintide was designed at Novo Nordisk as a stabilised amylin analogue carrying a C20 fatty-diacid side chain, the same lipidation idea used in semaglutide. The 2021 medicinal-chemistry paper describes how the sequence was altered to resist breakdown and to keep the molecule from forming fibrils, while the side chain gave it a half-life long enough for once-weekly dosing.

What it does — in plain terms

Amylin is one of the signals that tells the brain a meal has arrived. In research, cagrilintide acts on the same amylin receptors, and trial participants receiving it ate less and their body weight changed in a dose-dependent way. Much of the current interest is in pairing it with a GLP-1 analogue, because the two signals reach the brain by different routes.

How it works

Amylin receptors are built from a calcitonin receptor plus a small partner protein called a RAMP. Cagrilintide binds these receptor complexes, and a 2025 mechanism study in mice traced the body-weight effect specifically to amylin receptors 1 and 3 in the brain.

The downstream picture is a satiety signal: activity in the area postrema and related brainstem regions, slower gastric emptying, and reduced food intake. This is a different pathway from GLP-1 receptor agonists, which is the rationale for studying the two together.

Because the molecule is albumin-bound, its concentration in blood rises and falls slowly. Trial protocols therefore escalate the dose over weeks, and the phase 1 combination study looked closely at how the two long-acting molecules behaved side by side.

What the research shows

Cagrilintide is unusual among research peptides in having a large, published human-trial record: a phase 2 dose-finding trial, a phase 1 combination study, and phase 3 trials of the cagrilintide plus semaglutide pairing. The honest caveat is that all of this comes from one sponsor's development programme, and the peptide is not an approved product on its own.

• Lancet, 2021 — in a 26-week, placebo- and active-controlled dose-finding trial, once-weekly cagrilintide produced dose-dependent body-weight change versus placebo, with the highest doses comparing favourably with the active control.
• Journal of Medicinal Chemistry, 2021 — described the design of cagrilintide: sequence changes for stability and against fibril formation, plus a fatty-diacid side chain for albumin binding and a week-long action.
• EBioMedicine, 2025 — showed in mice that cagrilintide's effect on body weight depends on amylin receptors 1 and 3 in the brain, narrowing down where the signal acts.
• Lancet, 2021 (phase 1) — tested multiple doses of cagrilintide given alongside semaglutide 2.4 mg, reporting on safety, tolerability and the pharmacokinetics of the two molecules together.
• New England Journal of Medicine, 2025 — reported a phase 3 trial of co-administered cagrilintide and semaglutide in adults with overweight or obesity, the largest published test of the pairing.

What Cagrilintide is studied for

Body-weight change. The central question of the trial programme. Results are reported as the percentage change in body weight over the trial period against placebo, not as a treatment claim.

Amylin-receptor signalling. Cell and animal work maps which receptor complexes the molecule binds and which brain regions carry the effect, most recently pointing at amylin receptors 1 and 3.

Co-administration with semaglutide. Because amylin and GLP-1 signal through different routes, the combination has been studied from phase 1 through phase 3 to see whether the effects add.

Appetite and energy intake. Trial sub-studies and animal work measure food intake and gastric emptying to explain how the weight change comes about.

Storage & handling

As a lyophilized (freeze-dried) powder, cagrilintide reference material is most stable kept cold and dark, refrigerated or frozen for longer holds. Once reconstituted with bacteriostatic water it should be refrigerated at roughly 2-8 °C, kept out of light, and protected from repeated freeze-thaw cycles. See the VNG reconstitution guide for the concentration math.