Research Library

Cagrilintide vs SM: Amylin and Incretin Compared

Cagrilintide is a long-acting amylin analogue; SM is a GLP-1 receptor agonist. They act through different satiety pathways, which is why the interesting research question has been combination rather than substitution — the CagriSema programme tests exactly that.

Summary

Last reviewed 2026-09-01

What it is

A comparison of two distinct satiety mechanisms: amylin receptor signalling in the area postrema and GLP-1 receptor signalling in the hypothalamus and brainstem.

Pramlintide established amylin analogue pharmacology clinically. Cagrilintide is a long-acting successor developed for weekly dosing, studied alone and combined with SM as CagriSema in the REDEFINE programme.

Cagrilintide is an acylated amylin analogue; SM is an acylated GLP-1 analogue.

Non-overlapping mechanisms raise the possibility of additive effect without simply amplifying one pathway's adverse effects.

How it works

In plain terms

Amylin is released with insulin after meals and signals fullness through a different brain route than GLP-1. Combining the two targets appetite from two directions at once.

Technical detail

Amylin is co-secreted with insulin by pancreatic beta cells and acts at amylin receptors — calcitonin receptor complexed with RAMP proteins — concentrated in the area postrema, slowing gastric emptying and suppressing glucagon. SM acts at GLP-1 receptors in the hypothalamic arcuate nucleus and brainstem. Because the receptors and circuits differ, combined administration produces effects greater than either alone in trial data, and cagrilintide has been proposed to preserve lean mass proportion better than incretin monotherapy, though that remains inadequately measured.

Pathways involved

Amylin receptor (CTR + RAMP) signalling in the area postrema
GLP-1R signalling in arcuate nucleus and brainstem
Shared downstream effects on gastric emptying and glucagon suppression

Current research

Laboratory research

Receptor pharmacology of both classes is well characterised; RAMP-dependent amylin receptor composition is established.

Animal research

Combination amylin plus GLP-1 agonism produced greater food intake reduction than either alone across rodent models.

Human research

The CagriSema combination in phase 2 reported greater reduction than either component alone.

Ongoing research

The REDEFINE programme continues; long-term outcome data does not yet exist for cagrilintide.

What is being investigated

Additive effect of combining non-overlapping satiety mechanisms
Whether amylin agonism preserves lean mass proportion
Tolerability of combination versus incretin monotherapy
Glucagon suppression and glycaemic contribution

These are research directions reported in the literature, not established effects or recommendations.

Risks, limitations and unknowns

Read this section before the rest

Cagrilintide has no cardiovascular outcome data, unlike SM
Combination therapy compounds gastrointestinal adverse effects
Lean mass preservation claims are mechanistically plausible but not adequately demonstrated
REDEFINE-1 dose-adjustment rates suggest tolerability is a real constraint
Comparing monotherapy cagrilintide to SM favours SM; the combination is the actual research proposition

Evidence ratings

SM human data

Strong

Large phase 3 programme plus outcome trial.

Cagrilintide monotherapy

Moderate

Phase 2 data; weaker alone than SM.

CagriSema combination

Moderate

REDEFINE-1 phase 3 reported; outcome data absent.

Lean mass preservation

Limited

Plausible but not properly measured.

Comparisons

TZ vs SM

Direct head-to-head incretin data.

RT vs tz

Triple versus dual agonism.

References

[1]Cagrilintide phase 2 obesity trial — PubMed / Lancet, 2021
[2]CagriSema REDEFINE-1 — PubMed / ClinicalTrials.gov, 2024–2025
[3]Amylin receptor pharmacology — PubMed, 2015–present
Reference links open searches and records on PubMed and ClinicalTrials.gov so that every statement above can be traced to primary literature.

Frequently asked questions

What is cagrilintide?+

A long-acting amylin analogue designed for weekly dosing, studied alone and combined with SM as CagriSema.

How does amylin differ from GLP-1?+

Amylin acts at calcitonin-receptor-based amylin receptors in the area postrema; GLP-1 acts at GLP-1 receptors in the hypothalamus and brainstem.

Does cagrilintide preserve muscle?+

It has been proposed, and is mechanistically plausible, but body composition has not been measured well enough to conclude it.

Does combining the two worsen side effects?+

Combination therapy adds gastrointestinal burden from both mechanisms; dose adjustment was common in phase 3.

Is there outcome data for cagrilintide?+

No cardiovascular or long-term outcome data exists, in contrast to SM's SELECT trial.

What was pramlintide?+

The first clinically used amylin analogue, requiring frequent injection, which established the pharmacology cagrilintide builds on.

Continue your research

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