Retrospective analysis of safety and efficacy of insulin-to-liraglutide switch in Japanese type 2 diabetes: A caution against inappropriate use in patients with reduced β-cell function.

AIMS/INTRODUCTION: The safety and efficacy of insulin-to-liraglutide switch in type 2 diabetes has not been studied adequately. Here, we retrospectively characterize clinical parameters that might predict insulin-to-liraglutide treatment switch without termination due to hyperglycemia, and examine the effects of switching the therapies on glycated hemoglobin (HbA1c) and bodyweight in Japanese type 2 diabetes. MATERIALS AND METHODS: Japanese type 2 diabetes patients who underwent the switch of therapy were evaluated for their clinical data including β-cell function-related indices, such as increment of serum C-peptide during glucagon stimulation test (GST-ΔCPR). HbA1c and bodyweight were analyzed in patients continuing with liraglutide after switching from insulin for 12 weeks. RESULTS: Of 147 patients, 28 failed in the switch due to hyperglycemia, nine failed because of other reasons and 110 continued with liraglutide for the 12-week period. Patients failing in the switch due to hyperglycemia showed longer duration and higher daily insulin dose, as well as lower GST-ΔCPR. Receiver-operating characteristic analysis showed that GST-ΔCPR of 1.34 ng/mL is a cut-off point for insulin-to-liraglutide switch without termination due to hyperglycemia. In patients continuing liraglutide for 12 weeks, the switch significantly reduced HbA1c and bodyweight with no severe hypoglycemia, irrespective of sulfonylurea co-administration, body mass index, duration and total daily insulin dose. The switch also significantly reduced the percentage of body fat and visceral fat areas. CONCLUSIONS: Insulin-to-liraglutide switch can improve glycemic control and reduce bodyweight in Japanese type 2 diabetes patients. However, caution must be taken with the switch in patients with reduced insulin secretory capacity as predicted by GST-ΔCPR.