Cagrilintide

Cagrilintide is an investigational analogue of amylin, a pancreatic hormone released alongside insulin that contributes to meal-ending satiety. Amylin signalling works through a different circuit from GLP-1 — the hindbrain rather than the hypothalamus — which is the whole rationale for combining the two hormones instead of escalating one. It matters to readers because the combination products now dominate late-stage metabolic research, and because cagrilintide appears in grey-market listings even though no country has approved it. As with every unapproved compound in this library, the appeal is a mechanism with plausible biology and the risk is that the human safety record simply does not exist yet.

Cagrilintide is a modified human amylin with fatty-acid acylation that extends its action to a weekly dosing interval. It activates amylin receptors in the area postrema of the hindbrain, which reduces food intake and slows gastric emptying, and it appears to restore the satiety response that is blunted in obesity. Combined with a GLP-1 agonist, the two hormones act on separate appetite circuits, which is why the combination produces greater weight loss than either alone at the doses tested.

• Adds measurable weight reduction on top of a GLP-1 agonist in combination trials
• Acts on a satiety pathway distinct from GLP-1, which is the reason for pairing it
• Weekly subcutaneous dosing in trial protocols
• Reduced food intake and slower gastric emptying in mechanistic studies

Reported benefits describe what the published literature and user reports suggest — not a promise of outcome for any individual.

The evidence is concentrated in the phase 3 combination programme and in earlier phase 2 work on the amylin analogue alone. In the combination trials, participants reaching the highest dose lost more weight than those on semaglutide alone, with reductions of the order of 20% at around 68 weeks in the pivotal study — a result that made the pairing one of the most watched in the field. Safety findings have largely mirrored the incretin class: gastrointestinal effects during escalation, gallbladder events, and modest heart-rate changes. As with all of these compounds, the unresolved questions are about lean-mass loss, long-term cardiovascular effects and what happens after treatment stops rather than about whether appetite suppression works.

• Nausea, vomiting and diarrhoea during escalation
• Constipation
• Reduced appetite to the point of inadequate protein and calorie intake in some users
• Gallbladder disease
• Injection-site reactions

Unapproved and unstudied in long-term trials as a standalone product. Anyone self-administering a research-grade amylin analogue alongside a GLP-1 agonist is combining two appetite-suppressing mechanisms with no monitoring, no titration support and no adverse-event reporting. Personal or family history of medullary thyroid carcinoma or MEN2, previous pancreatitis, and pregnancy all argue against it. Loss of lean mass during rapid weight loss is a real consideration, which is why trials pair these compounds with protein targets and resistance training.

It is designed to be stacked with a GLP-1 agonist, but only inside a clinical protocol with titration and monitoring. Outside that setting there is no sensible way to assess the interaction.