OBJECTIVES: Dapagliflozin, a novel, selective, oral sodium-glucose co-transporter 2 (SGLT2) inhibitor, lowers glycated hemoglobin (HbA1c) along with reduction in body weight.  This study evaluated health-related quality of life (HRQOL) among type 2 diabetes mellitus (T2DM) patients treated with dapagliflozin in triple therapy during a 24-week period. METHODS: Patients with T2DM (mean age 61 years, 49% men, 96% with body mass index  ≥25 kg/m) who had inadequate glycemic control on combination of metformin (MET) and sulfonylurea (SU) were enrolled in a 24-week, international, double-blind, randomized, placebo-controlled study (NCT01392677) to evaluate the effect of dapagliflozin in combination with MET plus  SU on HbA1c and body weight.  Patients completed the EuroQol Group EQ-5D survey at baseline and at week 24 for evaluation as a secondary objective.  Patients treated with dapagliflozin 10 mg + MET + SU (n = 108) were compared with patients treated with placebo + MET + SU (n = 108), based on ANCOVA model with treatment group as an effect and baseline value as a covariate. RESULTS: EQ-5D visual analog scale (VAS, 0-100) baseline means (SD) were 74.6 (20.0) and 73.1 (20.5) for the dapagliflozin and placebo groups, respectively.  Corresponding 24-week values were 78.4 (15.2) and 76.8 (16.9), respectively.  VAS scores improved in both groups from baseline to week 24; however, there was no significant difference between groups (0.9; CI: -2.9, 4.8; p-value: 0.63) in adjusted change from baseline.  EQ-5D index (scores 0-1) baseline means were 0.84 (0.16) and 0.85 (0.16) for dapagliflozin and placebo, respectively.  Corresponding 24-week values were 0.83 (0.17) and 0.83 (0.16), respectively.  There was no difference in adjusted change from baseline between treatment groups (0.01; CI: -0.03, 0.05; p-value: 0.68). CONCLUSIONS: Similar to other dapagliflozin studies, patients in the present study maintained high HRQOL scores with dapagliflozin over a 24-week period.