CagrilintidevsMazdutide

Cagrilintide is a long-acting analogue of amylin, a 37-amino-acid peptide hormone naturally co-secreted with insulin from pancreatic beta cells after meals. Native amylin plays a crucial but often overlooked role in metabolic regulation — it signals satiety, slows gastric emptying, and suppresses post-meal glucagon secretion through mechanisms entirely distinct from the GLP-1 pathway.

Cagrilintide activates amylin receptors, which are heterodimeric complexes formed by the calcitonin receptor (CTR) paired with receptor activity-modifying proteins (RAMP1, RAMP2, or RAMP3). These receptors are concentrated in the area postrema and the nucleus tractus solitarius in the brainstem — regions outside the blood-brain barrier that can directly sense circulating peptides. Activation of these neurons triggers ascending satiety signals to the hypothalamus, reducing meal size and food-seeking behavior through pathways that are neuroanatomically separate from GLP-1 signaling.

This distinct mechanism is why cagrilintide produces additive appetite suppression when combined with semaglutide (as CagriSema) — the two peptides target different populations of neurons within the brain's appetite control circuitry. Cagrilintide has been engineered with acylation modifications that enable albumin binding, extending its half-life from minutes (native amylin) to approximately one week, making it suitable for weekly subcutaneous dosing.

Mazdutide is a dual-receptor agonist that activates both GLP-1 and glucagon receptors, combining appetite suppression with increased energy expenditure. The GLP-1 component functions similarly to other GLP-1 agonists — binding to receptors in the hypothalamus to reduce hunger, stimulating glucose-dependent insulin secretion from pancreatic beta cells, and slowing gastric motility to prolong post-meal satiety.

The glucagon receptor component distinguishes mazdutide from pure GLP-1 agonists. Glucagon binding in the liver activates adenylyl cyclase, increasing cAMP and activating protein kinase A, which phosphorylates key enzymes in fatty acid oxidation and ketogenesis. This drives the liver to burn stored fat as fuel rather than accumulate it — a mechanism with direct therapeutic relevance for patients with metabolic-associated fatty liver disease (MAFLD). In adipose tissue, glucagon signaling promotes lipolysis and may activate thermogenic programs in brown and beige fat cells.

The engineering challenge in dual GLP-1/glucagon agonists is balancing the hyperglycemic effect of glucagon against the glucose-lowering effects of GLP-1. Mazdutide achieves this by tuning the relative receptor affinities so that GLP-1-mediated insulin secretion offsets glucagon-driven glucose production, resulting in net glycemic improvement alongside enhanced fat oxidation and energy expenditure.