Effects of Sandostatin LAR® in Acromegaly

A major goal of treatment of acromegaly is to normalize serum IGF-1 levels. Recently developed new normative data for serum IGF-1 levels has lowered the upper limit of normal for this hormone level. Octreotide, an analog of somatostatin, a synthetic form of the hypothalamic hormone somatostatin, which inhibits growth hormone (GH) release by blocking somatostatin receptors in the pituitary and on the tumor, is now available in a long acting depot formulation, Sandostatin LAR, that suppresses tumoral GH secretion and normalizes GH and IGF-1 levels in about 60% of patients. Although sandostatin LAR is Food and Drug Administration (FDA) approved for the therapy of acromegaly and is used clinically, its efficacy with respect to new normative IGF-1 ranges has not been studied. In addition, an important goal of therapy of acromegaly is to treat co-morbidities of the disease such as insulin resistance, which is common in acromegaly. Other important morbidities in acromegaly are hypertension and cardiovascular disease such as left ventricular hypertrophy (LVH). In this study the investigators will assess the effect of LAR therapy on biochemical parameters as well as important clinical endpoints of therapy of acromegaly.