Endocrine Abstracts

In acromegalic patients not suitable for first-line surgical treatment, pharmacotherapy is a valuable choice. Depot somatostatin analogs (SSA) represent efficacious and well-tolerated drugs; however, they normalize hormonal parameters in no more than 65–75%. Pegvisomant (PEGA), a GH receptor antagonist, has been shown to normalize IGF-I levels in more than 90% of patients. We report our experience in 13 acromegalic patients (7 M, 6 F; age: 50.2±3.9 yrs; 7 macroadenomas, 3 microadenomas and 3 empty sella) treated for 3–44 months (mean 28.8±3.7 month) with PEGA (5–25 mg/day, mean 15.8±1.6 mg/day) alone (n. 8) or combined with SSA (octreotide 10–30 mg/month). Diabetes mellitus or IGT was present in 5 patients. IGF-I and IGFBP-3 levels, glucose metabolism, clinical picture, MRI and safety parameters were monitored. Basal IGF-I and BP-3 levels were 858.3±90.4 μg/l and 6.2±0.4 μg/ml, respectively. During PEGA IGF-I normalized (222.4±20.6 μg/l, P<0.005) in 12/13 patients within 12 months with a mean PEGA dose of 15.8±1.6 mg/day. Also IGFBP-3 markedly decreased (3.8±0.3 μg/ml, P<0.005). Morning glucose levels decreased from 104.2±6.3 mg/dl to 92.6±6.2 mg/dl (P<0.05) but HbA1c didn’t change (5.7±0.2% vs 5.9±0.3%) even when only diabetic and IGT patients were considered (7.1±0.9% vs 6.8±0.4%). All patients improved clinical picture and acromegalic signs and symptoms. No change occurred at pituitary MRI imaging in any patient. One patient had slight and transient increase in transaminases. One female patient complained abdominal lipodistrophy in the injection site. Thus, PEGA normalizes IGF-I in almost all patients, improves the clinical picture and also glucose levels, in front of good safety profile.