Efficacy of Initial Basal-Supported Oral Therapy with Sitagliptin in Untreated Type 2 Diabetes

Introduction: The present study assessed the efficacy of initial basal-supported oral therapy (BOT) with sitagliptin for achievement of glycemic control and subsequent switching from BOT to sitagliptin-based oral therapy. Methods: Nineteen recently diagnosed type 2 diabetic patients who had received no antidiabetic medication in the previous 2 years were sequentially examined for the 24-week study. Patients were initially treated with a combination of insulin glargine and sitagliptin. Sitagliptin was initiated and maintained at a dose of 50 mg/day, and insulin glargine was started at a dose of 4 U at bedtime and adjusted if needed. Results: During the 24-week treatment period, 12 patients (63%) achieved HbA1c levels <7% (mean BOT duration 13.7 +/- 5.6 weeks) and switched from BOT to sitagliptin monotherapy or in combination with metformin (achievers). The remaining seven patients (37%) failed to achieve HbA1c levels <7% (non-achievers) and continued on BOT. Both FPG and HbA1c in achievers significantly dropped at 4, 8, 12 and 24 weeks from baseline, while those in non-achievers significantly decreased at 12 and 24 weeks from baseline, but failed to reach target glycemic control. There were statistically significant differences in FPG at 4, 8, 12 and 24 weeks and in HbA1c at 8, 12 and 24 weeks between achievers and non-achievers. Body weight and BMI in achievers were significantly reduced at 12 and 24 weeks, but those in non-achievers did not change significantly. Dosage of concomitant insulin during BOT was significantly lower in achievers compared to non-achievers. Non-achievers had a similar CPI, a measure of insulin secretion capacity, to achievers, but significantly showed an insulin resistance index (value of 20/[fasting CPR x FPG]), in comparison to achievers. Conclusion: Initiating BOT with sitagliptin followed by sitagliptin-based oral therapy is a useful option in untreated and poorly controlled patients with type 2 diabetes.