Peptide Database

CCK · CCK-8

Cholecystokinin (CCK) is a peptide hormone produced by duodenal I-cells and neurons in the CNS. It triggers gallbladder contraction, pancreatic enzyme secretion, and potently suppresses appetite via vagal nerve CCK1 receptors. In the brain, CCK neurons modulate anxiety, pain, memory consolidation, and dopamine release. CCK antagonists are studied for anxiety and pain; CCK agonists for obesity and eating disorders.

Byetta · Bydureon

Exenatide is a GLP-1 receptor agonist derived from exendin-4, a peptide found in Gila monster saliva. The first GLP-1 RA approved for type 2 diabetes, it established the GLP-1 drug class. Extended-release formulations (Bydureon) allow once-weekly dosing. Emerging research explores repurposing for Parkinson's disease, where small trials show motor improvement, and Alzheimer's disease neuroprotection.

GAL

Galanin is a 29-30 amino acid neuropeptide widely distributed throughout the CNS and peripheral nervous system. It modulates memory, mood, pain, seizures, appetite, and sleep via three receptor subtypes (GALR1–3). Research focuses on its roles in Alzheimer's disease (galanin hyperinnervation of cholinergic neurons), depression, epilepsy, and eating behavior. Both agonists and antagonists have therapeutic potential depending on the target condition.

Glucose-dependent Insulinotropic Polypeptide · Gastric Inhibitory Polypeptide

GIP is a 42-amino-acid incretin hormone secreted by duodenal K-cells in response to fat and carbohydrate ingestion. Like GLP-1, it enhances glucose-dependent insulin secretion. Unlike GLP-1, it also promotes insulin secretion during hypoglycemia, protects β-cells, and at high doses may stimulate glucagon in a glucose-independent manner. The GIP receptor's role in energy homeostasis underlies the efficacy of dual GIP/GLP-1 agonists like tirzepatide.

GCG

Glucagon is a 29-amino-acid pancreatic alpha-cell hormone and physiological counter-regulator to insulin. It raises blood glucose through hepatic glycogenolysis and gluconeogenesis and is also lipolytic and thermogenic at supraphysiological doses. FDA-approved for hypoglycemia rescue and GI relaxation, it is now a major drug design target as a component of dual (GLP-1/glucagon) and triple agonists for obesity and NASH treatment.

Victoza · Saxenda

Liraglutide is a once-daily GLP-1 receptor agonist approved for type 2 diabetes (Victoza) and obesity (Saxenda). It achieves fatty acid attachment to albumin for extended half-life, enabling daily dosing. The LEADER trial established significant cardiovascular mortality benefit in high-risk patients, and research continues into neuroprotective and anti-inflammatory properties beyond metabolic indications.

LY3437943

Retatrutide is a triple agonist targeting GIP, GLP-1, and glucagon receptors simultaneously. Phase 2 trials demonstrated up to 24.2% body weight reduction — the highest achieved by any pharmacotherapy to date. The addition of glucagon agonism enhances energy expenditure and lipid metabolism beyond dual incretin agonists. Phase 3 trials are underway for obesity and NASH.

Ozempic · Wegovy

Semaglutide is a long-acting GLP-1 receptor agonist approved for type 2 diabetes (Ozempic, Rybelsus) and obesity (Wegovy). By mimicking the incretin hormone GLP-1, it enhances glucose-dependent insulin secretion, suppresses glucagon, slows gastric emptying, and reduces appetite via central hypothalamic pathways. Landmark trials demonstrate up to 15–17% body weight reduction and significant cardiovascular mortality benefit.

Mounjaro · Zepbound

Tirzepatide is the first dual GIP/GLP-1 receptor agonist, approved for type 2 diabetes (Mounjaro) and obesity (Zepbound). By co-activating both incretin receptors, it achieves superior glycemic control and weight reduction compared to GLP-1 monotherapy — SURMOUNT trials showed up to 22.5% body weight reduction. It represents a new class of metabolic peptide therapeutics with broad cardiovascular and metabolic benefits.