The Definitive Peptide Research Reference Guide — Compound Review

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GLP-1 Peptides Research Hub

The complete research reference for GLP-1 receptor agonists — covering all three generations of the drug class, from semaglutide through retatrutide.

What Are GLP-1 Peptides?

GLP-1 (glucagon-like peptide-1) is an incretin hormone secreted by L-cells in the small intestine in response to food intake. It acts on receptors in the pancreas to stimulate insulin secretion, suppress glucagon, slow gastric emptying, and signal satiety to the hypothalamus.

The Three Generations

First generation: GLP-1 monotherapy (semaglutide, liraglutide). Second generation: GIP/GLP-1 dual agonism (tirzepatide). Third generation: GIP/GLP-1/glucagon triple agonism (retatrutide). Each generation expands receptor coverage to produce progressively greater metabolic effects.

Complete GLP-1 Research Index

All GLP-1 content on CompoundReview, organized by topic — mechanism guides, dosage protocols, head-to-head comparisons, and clinical trial summaries.