Metabolic Effects of Long-Acting Somatostatin Analogue (Sandostatin) in Type I Diabetic Patients on Conventional Therapy

We evaluated the effectiveness of a more potent and longer-acting somatostatin analogue (SMS 201–995) as an adjunct to insulin therapy, in a double-blind placebo-controlled randomized study of 26 C-peptide-negative type I (insulin-dependent) diabetic patients (20 women, 6 men, aged 22–40 yr) on their conventional drug regimens for 12 wk. Eight patients received a low dose (10 μg) of the analogue, 9 received a high dose (50 μg) of the analogue, and 9 received placebo subcutaneously before breakfast and dinner. Twenty-four-hour serum glucose, free insulin, plasma growth hormone (GH), and glucagon profiles were obtained before and during treatment at 4-wk intervals. The mean age, duration of diabetes, daily insulin dose, and body weight were not significantly different among the groups. The mean weekly capillary blood glucose values and exogenous insulin requirements were not changed by the SMS 201–995 therapy. Mean glycosylated hemoglobin A₁ levels were unchanged in both the analogue- and placebo-treated groups at wk 12. Basal and postprandial glucose, free insulin, GH, and glucagon profiles were not influenced by the SMS 201–995 therapy throughout the study. Nocturnal glucose turnover rates (D-[3-³H]glucose technique) remained unaltered by the analogue therapy. Dose-dependent gastrointestinal (GI) adverse effects (e.g., diarrhea) were documented in the analogue-treated patients. Visual acuity and fundic photomicrographs of our patients were not changed by the analogue therapy. In conclusion, the prominent adverse GI effects our patients experienced preclude the use of larger doses of the analogue that may be necessary to suppress GH and glucagon and improve glucose control in type I diabetic patients.