Temporary Preservation of β-Cell Function by Diazoxide Treatment in Childhood Type 1 Diabetes

OBJECTIVE —We examined the effect of diazoxide, an ATP-sensitive K+ channel opener and inhibitor of insulin secretion, on β-cell function and remission in children at clinical onset of type 1 diabetes. RESEARCH DESIGN AND METHODS —A total of 56 subjects (21 girls and 35 boys, age 7–17 years) were randomized to 3 months of active treatment (diazoxide 5–7.5 mg/kg in divided doses) or placebo in addition to multiple daily insulin injections and were followed for 2 years. RESULTS —Diazoxide decreased circulating C-peptide concentrations by ∼50%. After cessation of the treatment, basal and meal-stimulated C-peptide concentrations increased to a maximum at 6 months, followed by a decline. Meal-stimulated C-peptide concentration was significantly higher at 12 months (0.43 ± 0.22 vs. 0.31 ± 0.26 nmol/l, P = 0.018) and tended to fall less from clinical onset to 24 months in the diazoxide- vs. placebo-treated patients (−0.05 ± 0.24 vs. −0.18 ± 0.26 nmol/l, P = 0.064). At 24 months, the meal-stimulated C-peptide concentrations were 0.24 ± 0.20 and 0.20 ± 0.17 nmol/l, respectively. Side effects of diazoxide were prevalent. CONCLUSIONS —This study demonstrates that partial inhibition of insulin secretion for 3 months at onset of childhood type 1 diabetes suspends the period of remission and temporarily preserves residual insulin production. Further evaluation of the full potential of β-cell rest will require compounds with less side effects as well as protocols optimized for sustained secretory arrest.