NEW YORK (Reuters Health) – Daily treatment with diazoxide prompts a decrease in HbA1c in patients with newly diagnosed type 1 diabetes, Norwegian researchers report in the December 22nd online issue of Diabetes Care.

"Our results demonstrate a safe and beneficial effect of intervention with diazoxide" in these patients, lead author Dr. Maria Anita Radtke told Reuters Health by email.

Dr. Radtke of the Norwegian University of Science and Technology, Trondheim, and colleagues observe that in prior studies, diazoxide preserved insulin production in type 1 diabetics, but side effects were common. In those trials, however, diazoxide was given three times a day, with total daily doses often exceeding 300 mg.

In the current study, the researchers used once-daily treatment with 100 mg, a regimen that’s been successful in type 2 diabetics.

Forty-one newly diagnosed type 1 diabetics were randomized to 6 months treatment with placebo or diazoxide, given at bedtime.

In the active treatment group, mean HbA1c fell from 8.6% at baseline to 6.0% at 6 months. The effect persisted, and HbA1c was 6.5% at 12 months. This was a significant improvement over the 8.3%, 7.3% and 7.5% seen in placebo patients (p < 0.05).

The reason for the improved glycemic control is not clear, however. Fasting and stimulated C-peptide decreased similarly in both groups, and the proportion of FoxP3+ regulatory T-cells also remained comparable and stable over 12 months.

One possibility, the authors suggest, is that improved insulin production was not picked up by the testing methods employed.

Only three patients dropped out of the study due to treatment-related side effects (dizziness, rash, and sleep disturbance). No others had adverse effects.

While diazoxide appears to be beneficial in these patients, "we need to do further studies in order to pinpoint the exact mechanisms behind the effect," Dr. Radtke said.

Diabetes Care 2009.