Ellis SL et al. – Sitagliptin significantly improved overall glucose control, including postprandial and 24–h glucose control, in adult patients with Type 1 diabetes, while significantly reducing prandial insulin requirements. Further investigation is warranted in patients with Type 1 diabetes in a larger cohort designed to assess both clinical outcomes and mechanism of action.

• This investigator–initiated, double–blind, randomized, crossover, 8–week, pilot study enrolled 20 adult subjects with Type 1 diabetes. Subjects received sitagliptin 100 mg/day or placebo for 4 weeks and then crossed over.
• Outcomes included 2–h postprandial blood glucose and 24–h area under the curve changes in glucose measurements from continuous glucose monitoring, HbA1c, fructosamine and insulin dose.

• Sitagliptin significantly reduced blood glucose (2–h postprandial and 24–h area under the curve) despite reduced total and prandial insulin dose.
• Based on continuous glucose monitor findings, sitagliptin improved measures of glycaemic control, including mean blood glucose (–0.6 mmol/l; P = 0.012) and time in euglycaemic range 4.4–7.8 mmol/l (0.4 ± 0.2 h; P = 0.046).
• Significant reductions were also observed in M100, Glycemic Risk Assessment Diabetes Equation (GRADE) and J–index.
• After controlling for period, treatment and insulin dose, the HbA1c was also significantly reduced [-0.27 ± 0.11% (–2.91 ± 1.16 mmol/mol); P = 0.025] when patients were taking sitagliptin.