Peptide Database
86 therapeutic peptides with research summaries, clinical findings, and regulatory status.
Octreotide (Sandostatin)
A synthetic octapeptide analog of somatostatin with a substantially longer half-life (90 minutes IV, 6 hours subcutaneous vs. 2 minutes for native somatostatin). Octreotide binds somatostatin receptors (primarily SSTR2 and SSTR5) to inhibit the secretion of GH, glucagon, insulin, gastrin, secretin, VIP, and other GI hormones. It reduces splanchnic blood flow, GI motility, and exocrine pancreatic secretion.
Lanreotide (Somatuline Depot)
A synthetic octapeptide analog of somatostatin with high affinity for SSTR2 and moderate affinity for SSTR5 receptors. Lanreotide is formulated as a supersaturated solution that forms a drug depot at the injection site, providing sustained release over 4 weeks. It inhibits GH secretion, GI hormone release, and has direct antiproliferative effects on neuroendocrine tumor cells through cell cycle arrest and apoptosis induction.
Pasireotide (Signifor)
A multireceptor-targeted somatostatin analog with high binding affinity for SSTR1, SSTR2, SSTR3, and SSTR5, particularly notable for its 40-fold greater affinity for SSTR5 compared to octreotide. This receptor profile makes pasireotide uniquely effective in Cushing's disease, where corticotroph adenomas predominantly express SSTR5. Pasireotide suppresses ACTH secretion from pituitary corticotroph tumors, reducing cortisol production.
Plecanatide (Trulance)
A synthetic 16-amino acid peptide structurally related to uroguanylin, an endogenous intestinal peptide that regulates fluid and electrolyte homeostasis in the GI tract. Plecanatide activates guanylate cyclase-C (GC-C) receptors on intestinal epithelial cells in a pH-dependent manner, preferentially in the proximal small intestine where pH is slightly acidic. GC-C activation increases intracellular and extracellular cGMP, stimulating chloride and bicarbonate secretion while reducing visceral pain signaling.
Linaclotide (Linzess)
A synthetic 14-amino acid peptide structurally related to the heat-stable enterotoxin of Escherichia coli and the endogenous peptide guanylin. Linaclotide activates guanylate cyclase-C (GC-C) on the luminal surface of intestinal epithelium, increasing intracellular cGMP to stimulate CFTR-mediated chloride and bicarbonate secretion, accelerating intestinal transit. Extracellular cGMP also reduces firing of visceral afferent pain fibers, providing analgesic effects in the gut.
Secretin
A 27-amino acid peptide hormone produced by S-cells of the duodenal and jejunal mucosa in response to acidic chyme entering the small intestine. Secretin stimulates pancreatic ductal cells to secrete bicarbonate-rich fluid, neutralizing duodenal acid, and promotes bile flow from hepatocytes. It was the first hormone ever identified (Bayliss and Starling, 1902) and serves as a key diagnostic tool in gastroenterology and endocrinology.
Larazotide
A synthetic octapeptide derived from Vibrio cholerae zonula occludens toxin that acts as a tight junction regulator. Larazotide acetate modulates intestinal permeability by preventing zonulin-mediated opening of tight junctions between enterocytes. By reducing paracellular permeability, it aims to prevent gluten peptide translocation across the intestinal barrier in celiac disease, reducing the immune-mediated inflammatory response triggered by gluten exposure.