Current status and future directions of pharmacological therapy for acromegaly

Acromegaly is a chronic systemic disorder caused in the vast majority of cases by a GH-secreting pituitary adenoma and resulting in significant morbidity and mortality if left untreated. The treatment of choice is the trans-sphenoidal resection of the adenoma, and although 80% of patients with microadenomas or confined macroadenomas achieve biochemical remission, the surgical success rate for patients harboring tumors with extrasellar extension is below 50%. Thus, a considerable proportion of patients will require some form of adjuvant treatment. Acromegaly can be approached pharmacologically by inhibiting GH secretion by the tumor (somatostatin analogues, dopamine agonists) or by antagonizing GH actions at its target tissues (GH receptor antagonists). The primary pharmacological treatment of acromegaly is increasingly gaining acceptance by both physicians and patients. The decision to use primary pharmacological treatment has to take into account the clinical characteristics of the patient (presence of comorbidities that significantly increase the surgical risk) and the biological nature of the adenoma (tumor size and location), as well as other aspects such as the availability of a pituitary surgeon and the cost of medications. This review provides a critical summary and update of the pharmacological treatment of acromegaly focusing both, on well-established agents and strategies as well as on novel compounds that are currently being developed.