Amylin, a pancreatic β-cell hormone co-secreted with insulin, acts on central nervous system circuits to produce satiation, slow gastric emptying, and suppress glucagon — mechanisms fundamentally separate from GLP-1 receptor pathways. A new class of long-acting analogs — cagrilintide, eloralintide, petrelintide, and NN1213 — engineered through lipidation and reversible albumin binding, differ critically in whether they activate amylin receptors selectively or engage calcitonin receptors simultaneously. That distinction, the authors argue, governs whether appetite reduction reflects genuine satiation or aversive nausea signaling through hindbrain and parabrachial circuits.
This review arrives at a clinically pivotal moment. GLP-1 receptor agonists like semaglutide have transformed obesity treatment but carry substantial nausea, vomiting, and muscle-loss burdens that cause significant discontinuation. The amylin pathway offers a mechanistically orthogonal route — and early trial data on cagrilintide in combination with semaglutide (CagriSema) already show additive weight loss. The central question this paper frames sharply is whether calcitonin receptor co-engagement is a liability for tolerability, which has direct implications for which compounds advance. Limitations are significant: this is a narrative review, not original trial data, and species differences in amylin receptor distribution complicate translating preclinical tolerability findings to humans. Still, the framework connecting receptor pharmacology to neural circuit recruitment represents a meaningful conceptual advance for rational drug design — making this a valuable orientating piece for anyone tracking the next wave beyond GLP-1 dominance.
