The potential role of the investigational somatostatin analog pasireotide (SOM230) in the treatment of neuroendocrine disorders

Purpose of reviewMany neuroendocrine tumors express a variety of somatostatin receptor subtypes and somatostatin analogues are used in medical treatment. The development of pasireotide (SOM230), a novel somatostatin analogue with multiligand properties, may offer a new potential therapy for these tumors. This review considers in-vitro, animal and early human clinical studies of pasireotide (SOM230). Recent findingsSomatostatin analogues, such as lanreotide and octreotide, are effective in many patients, but biochemical control is not achieved in over one third of patients with acromegaly, and in carcinoid, symptoms may become refractory after chronic use. Pasireotide, with high affinity binding to four of the five subtypes of somatostatin receptors (1, 2, 3, and 5) may control hormone oversecretion or tumor proliferation. Somatostatin receptor-5 appears to be important in regulating adrenocorticotropic hormone secretion, suggesting the possible use of pasireotide in Cushing's disease. Preliminary results from phase II studies of pasireotide in acromegaly, Cushing's, and carcinoid are presented. SummaryShort-term, small clinical studies using pasireotide for acromegaly and pituitary Cushing's and for symptomatic relief in refractory carcinoid are promising. Further investigation will determine whether pasireotide will be effective and safe for treating hormone excess, clinical symptoms or tumor proliferation in neuroendocrine disorders.