Somatostatin agonists for treatment of acromegaly

The discovery of somatotropin-release inhibitory factor (SRIF) in hypothalamic extract in 1970 led to the synthesis of the first somatostatin analog octreotide, discovery of five somatostatin receptor subtypes, and development of additional somatostatin receptor ligands (SRL) as pharmacotherapy for acromegaly and other neuroendocrine tumors. Long-acting formulations of SRL (octreotide LAR Depot, lanreotide SR and lanreotide autogel) assure improved patient compliance with weekly up to monthly injections, and are commonly used as primary or adjuvant treatment of acromegaly. We review SRL currently available, emphasizing long-acting compounds and their efficacy in controlling acromegaly. Disease control is evaluated by biochemical markers, tumor shrinkage, and disease-symptom improvement balanced against drug-related side effects.