Generally, somatostatin analogs are designed to emulate the structure of native somatostatins, while lacking the enzyme degradation sites of the native molecules. Octreotide and lanreotide (Fig. 2a, b) have long been used for treatment of acromegaly, hyperthyroidism, and gastroenteropancreatic neuroendocrine tumors. Another novel analog, somatoprim (DG3173), selectively binds sstr subtypes 2, 4, and 5 and has demonstrated suppression of growth hormone in octreotide-non-responsive cultured human somatotroph adenomas [34]. However, the clinical utility of somatoprim has not yet been evaluated.
Fig. 2 Chemical structures of somatostatin-14, octreotide, and pasireotide. Adapted from Bruns C, Lewis I, Briner U, Meno-Tetang G, Weckbecker G (2002) ©European Journal of Endocrinology, volume 146, page 710 [38]. Reproduced with permission