Objective To compare the efficacy and safety of an initial triple therapy using metformin, a dipeptidyl peptidase-4 (DPP4) inhibitor, and thiazolidinedione with a stepwise approach using sulfonylurea and metformin in new-onset, drug-naïve patients with type 2 diabetes.

Research design and methods Among drug-naïve patients with 9.0%–12.0% glycated hemoglobin (HbA1c) but no hyperglycemic symptoms, 100 subjects who started triple medications (metformin 1000 mg/day, sitagliptin 100 mg/day, and lobeglitazone 0.5 mg/day) were selected as an initial triple therapy group. Age and body mass index-matched subjects (n=100) who started glimepiride (≥2 mg/day with uptitration) and metformin (≥1000 mg/day with uptitration) were selected as a conventional therapy group. We investigated changes in HbA1c level, dynamic indexes for insulin sensitivity and β-cell function, and hypoglycemia.

Results After 12 months of treatment, HbA1c levels decreased significantly in both groups: from 10.7%±1.0% to 6.7%±1.3% in the triple group, and from 10.5%±1.0% to 7.3%±1.2% in the conventional therapy group. At 12 months, achievement of the HbA1c target (<7.0%) was higher in the triple group than in the conventional group (70% vs 52%, p<0.01). Dynamic indexes related to β-cell function and insulin sensitivity improved, and albuminuria reduced significantly only in the triple group. Hypoglycemia was more common in the conventional group.

Conclusions Initial triple combination therapy with the DPP4 inhibitor, metformin, and thiazolidinedione showed a higher achievement of the target HbA1c goal with a lower risk of hypoglycemia, better restoration of β-cell function, and multiple metabolic benefits, implying durable glycemic control. This strategy may be useful for patients presenting with type 2 diabetes and high HbA1c levels.