Hydroxychloroquine in decompensated, treatment-refractory noninsulin-dependent diabetes mellitus: A new job for an old drug?

Study Objective: To evaluate the usefulness and safety of hydroxychloroquine in patients with decompensated, treatmentrefractory noninsulin-dependent diabetes mellitus. Design: Prospective, randomized, placebo, double-blind 6-month trial. Patients: Thirty-eight patients with noninsulin-dependent diabetes resistant to commonly used therapies (oral drugs, insulin, combination of insulin and oral drugs). Interventions: Two study groups: one received insulin (n = 22) and the other, glibenclamide (n = 16). In each group, half of the patients were randomly allocated into two subgroups who continued the previous treatment but took either placebo tablets or hydroxychloroquine, 200 mg three times a day. The four subgroups were as follows: insulin and placebo (n = 11); insulin and hydroxychloroquine (n = 11); glibenclamide and placebo (n = 8); and glibenclamide and hydroxychloroquine (n = 8). Measurements and Main Results: At 6 months, relevant and statistically significant improvement occurred in the 11 patients who received the insulin and hydroxychloroquine (glucose profile decrease, -11.7 mmol/L; 95% CI, -13.9 to -9.5, P = 0.001; glycated hemoglobin A1c decrease, -3.3%; 95% CI, -3.9 to -2.7, P = 0.001). No significant changes were seen in patients on placebo. The daily insulin dose in patients treated with the combined insulin and hydroxychloroquine therapy had to be reduced an average of 30%. No important side effects were detected. Conclusions: Combining antidiabetic therapy with hydroxychloroquine in decompensated, treatment-refractory patients with noninsulin-dependent diabetes may help to break the vicious circle of hyperglycemia and lead to better management of the disease.