Octreotide

Category: peptide

Aliases: SMS 201-995, Sandostatin, Sandostatin LAR

Pharmacological Mechanism

Cyclic octapeptide with a disulfide bridge (Cys-2 – Cys-7) and D-Phe, D-Trp, Thr-ol modifications — producing 30× longer t½ than native somatostatin (1.5 h vs 2 min) and SSTR2 > SSTR5 selectivity. Suppresses GH + IGF-1 (acromegaly), inhibits hormone release from functional neuroendocrine tumours (carcinoid, VIPoma, glucagonoma), and reduces portal pressure acutely (variceal bleeding). LAR formulation: biodegradable PLGA microspheres release drug over ~4 weeks.

Half-Life (t½)

SC: 1.5h, IV: 1.5h, IM: 1.5h

Dosing Guidelines

• SC: Typical 100 mcg (Range: 50–200 mcg)
• IM: Typical 100 mcg (Range: 50–200 mcg)
• IV: Typical 100 mcg (Range: 50–200 mcg)

Target Organ Systems

• endocrine

Pathways It Modulates

• GI endocrine peptides (activator) — SST2 + SST5

Chemical Identifiers

• PubChem CID: 448601
• Formula: C49H66N10O10S2
• Molecular weight: 1019.2 g/mol
• InChIKey: DEQANNDTNATYII-OULOTJBUSA-N
• SMILES: C[C@H]([C@H]1C(=O)N[C@@H](CSSC[C@@H](C(=O)N[C@H](C(=O)N[C@@H](C(=O)N[C@H](C(=O)N1)CCCCN)CC2=CNC3=CC=CC=C32)CC4=CC=CC=C4)NC(=O)[C@@H](CC5=CC=CC=C5)N)C(=O)N[C@H](CO)[C@@H](C)O)O

References

• PMID 2876508