Glycaemic control with add-on thiazolidinedione or a sodium-glucose co-transporter-2 inhibitor in patients with type 2 diabetes after the failure of an oral triple antidiabetic regimen: A 24-week, randomized controlled trial

Aim: To evaluate the effectiveness and safety of adding either a sodium-glucose co-transporter-2 inhibitor (SGLT2i) or thiazolidinedione (TZD) in patients with type 2 diabetes (T2D) inadequately controlled with triple therapy. Materials and Methods: In this prospective, open-label, multicentre, 24-week clinical trial, we randomly assigned 119 patients with T2D who failed to achieve glycaemic control (7% < HbA1c ≤ 10%) with conventional triple oral antidiabetic agents (OADs; metformin, sulphonylurea and dipeptidyl peptide-4 [DPP-4] inhibitor) into two groups who received either an SGLT2i or TZD. The primary endpoint was mean change in HbA1c level between the two groups at 24 weeks. Results: In total, 119 patients were enrolled in the SGLT2i (n = 60) and TZD (n = 59) groups. Mean age of the study subjects was 61.86 years, and the mean duration of T2D was 13.89 years. After 24 weeks, both groups showed significant reductions in HbA1c (from 7.94% ± 0.74% to 6.97% ± 0.84% in the SGLT2i group and from 8.00% ± 0.78% to 7.18% ± 0.98% in the TZD group), without a significant between-group difference (P =.235). A significant body mass index (BMI) reduction was noted in the SGLT2i group, whereas an increase in BMI was noted in the TZD group (−0.79 ± 1.37 vs. 0.92 ± 0.86 kg/m², P <.001). Other safety profiles were favourable in both groups. Conclusions: The current study shows that an SGLT2i or TZD could be a valid option as a fourth OAD for treatment of patients with T2D inadequately controlled with a triple combination of OADs.