Amylin and GLP-1 Together: The Science Behind Cagrilintide and CagriSema

What amylin is and what it does

Amylin is a 37 amino acid peptide secreted alongside insulin from pancreatic beta cells in proportion to meal size. It was first identified in 1987 in deposits of amyloid found in the pancreases of people with type 2 diabetes, which initially made it seem like a byproduct of disease rather than a useful hormone. Subsequent research established that it was a normal physiologic signal that becomes deficient as beta cell function declines.

The hormone acts on receptors in the hindbrain and hypothalamus, distinct from the GLP-1 receptor but working toward related goals. Amylin slows the rate of gastric emptying, suppresses glucagon release after meals, and signals satiety to the brain. In normal physiology it works alongside insulin and GLP-1 to manage the response after eating. In people with advanced type 2 diabetes or type 1 diabetes, amylin is absent or deficient because the same beta cells that produce insulin also produce amylin.

Why native amylin is not therapeutic

The problem with native amylin as a drug is its physical chemistry. Amylin in concentrated form tends to aggregate into insoluble fibrils, the same kind seen in pancreatic amyloid deposits in type 2 diabetes. This property makes it impractical for injection at therapeutic concentrations. It also clears rapidly from circulation, which would require frequent dosing to maintain any effect.

Researchers solved both problems differently for the two generations of amylin therapeutics. The first generation modified specific amino acids to prevent aggregation while preserving receptor activity. The second generation also added a fatty acid chain that anchors the molecule to albumin in circulation, extending the half life to roughly one week and making once weekly dosing feasible.

Pramlintide and the proof of concept

Pramlintide is a synthetic amylin analog developed by Amylin Pharmaceuticals that substitutes three amino acids to prevent fibril formation. It was approved by the FDA in 2005 as Symlin for adults with type 1 diabetes and for adults with type 2 diabetes taking mealtime insulin.

The approval was supported by randomized controlled trials showing that adding pramlintide to insulin therapy improved postprandial glucose control and modestly reduced body weight compared with insulin alone. However, pramlintide requires multiple daily injections before meals and has a narrow dosing window, which limited adoption in practice. The convenience advantage of once weekly GLP-1 receptor agonists has overshadowed it in most clinical settings.

The clinical value of pramlintide established something important: activating the amylin receptor in humans produces meaningful effects on glucose and body weight beyond what insulin alone achieves. That proof of concept supported the development of longer acting analogs designed for a once weekly schedule.

Cagrilintide: the once weekly amylin analog

Cagrilintide, developed by Novo Nordisk under the code AM833, is a synthetic amylin analog engineered for once weekly subcutaneous administration. It carries the same aggregation-preventing amino acid substitutions as pramlintide plus a fatty acid chain that extends its half life to approximately seven days, allowing it to be dosed on the same weekly schedule as semaglutide.

A phase 1b/2a trial of cagrilintide as monotherapy for weight management was published in The Lancet in 2021. The study examined five dose levels in adults with overweight or obesity over 26 weeks and reported dose dependent reductions in body weight compared with placebo. These results established that a once weekly amylin analog could produce meaningful effects on its own and supported advancing the compound to combination studies with semaglutide.

CagriSema: the dual pathway approach

CagriSema is a single injection combining cagrilintide and semaglutide in fixed doses. The two components target separate receptor pathways that each independently reduce food intake and slow gastric emptying. The hypothesis driving the combination is that activating both pathways produces weight and glucose effects that neither agent achieves alone at comparable doses.

• •Semaglutide component activates GLP-1 receptors in the hypothalamus and brainstem, suppresses appetite, and slows gastric emptying
• •Cagrilintide component activates amylin receptors in the area postrema and nucleus tractus solitarius through a separate circuit
• •Both components slow gastric emptying through different receptor mechanisms, potentially producing additive effects on postprandial satiety
• •The combination retains the once weekly dosing convenience of semaglutide alone

A phase 2 study of CagriSema in adults with type 2 diabetes was published in The Lancet in 2021, and early combination data from obesity studies supported advancement to phase 3. The REDEFINE program comprises multiple phase 3 trials evaluating CagriSema against semaglutide alone and placebo. Novo Nordisk reported topline results from REDEFINE 1, which evaluated CagriSema for weight management in adults with obesity or overweight, in late 2024. As of early 2025, detailed results were being prepared for regulatory submission and CagriSema had not been approved by any regulatory agency.

Safety and regulatory context

Adverse events reported across amylin receptor agonist trials have been predominantly gastrointestinal, consistent with the mechanism of slowing gastric emptying. Nausea and vomiting are the most commonly reported effects and tend to be most pronounced early in treatment or during dose escalation, a pattern similar to what is seen with GLP-1 receptor agonists.

Pramlintide carries a boxed warning in its prescribing information for severe hypoglycemia when used with insulin, particularly in people with type 1 diabetes. This is not an intrinsic property of amylin receptor activation but reflects the interaction with insulin dosing adjustments required when adding pramlintide. Cagrilintide is not administered with mealtime insulin in the CagriSema trials, so this specific interaction concern does not directly apply.

Cagrilintide and CagriSema are investigational compounds with no approved prescribing information. Material sold under these names as research chemicals is intended strictly for laboratory use and is not cleared for human administration. The absence of regulatory approval means there is no established safety database outside the controlled trial setting.

Compound reference pages