Glossary
GLP-1 Receptor Agonist
A GLP-1 receptor agonist switches on the GLP-1 receptor and is built to resist proteases. The two structural families and how they differ in practice.
GLP-1 receptor agonists are molecules that bind to and switch on the GLP-1 receptor, mimicking native GLP-1 signalling while being designed to withstand enzymatic degradation. The class was created because the natural hormone survives only about two minutes in plasma.
The two structural families
Analogs of human GLP-1 — liraglutide and semaglutide — retain the human backbone and add protective features: Aib at position 8 prevents DPP-4 cleavage, and a fatty-acid chain coupled through a linker at position 26 promotes reversible binding to albumin. Exendin-based agonists follow another strategy, relying on the exendin-4 sequence from Gila monster venom, which resists DPP-4 by nature thanks to the glycine at position 2.
Practical differences
When choosing a reference standard, the relevant parameters are potency at the receptor, plasma half-life, and whether other receptors are also engaged. The acylation of liraglutide gives it about once-daily duration; semaglutide’s C18 diacid plus an extra substitution stretch this to once weekly. Molecules acting at several receptors, such as dual and triple agonists, keep a GLP-1 component but are not simply categorised as GLP-1 receptor agonists.
Related terms
incretin. Browse GLP-1 and incretin peptides, or compare Semaglutide and Liraglutide in this research comparison.