Dapagliflozin as monotherapy in drug-naive Asian patients with type 2 diabetes mellitus: a randomized, blinded, prospective phase III study

Objective: Dapagliflozin is a highly selective, orally active inhibitor of renal sodium-glucose cotransporter 2 that reduces hyperglycemia by increasing urinary glucose excretion. The goal of this study was to evaluate dapagliflozin as monotherapy in drug-naive Asian patients with type 2 diabetes whose disease was inadequately controlled with diet and exercise.

Methods: In this Phase III, multicenter, parallel-group, double-blind study, drug-naive patients with glycosylated hemoglobin (HbA1c) levels ≥7.0% to ≤10.5% (≥53-≤91 mmol/mol) were randomized (by using an interactive voice response system) to receive placebo (n = 132), dapagliflozin 5 mg (n = 128), or dapagliflozin 10 mg (n = 133). The primary end point was mean change from baseline in HbA1c level at week 24 (last-observation-carried-forward). Secondary end points included changes in fasting plasma glucose, 2-hour postprandial glucose, body weight, and other glycemic parameters.

Results: Baseline characteristics were balanced across groups. Most patients (89%) were Chinese, median disease duration was 0.2 year, and mean HbA1c level was 8.26%. Most patients (87%) completed the study. At week 24, mean reductions in HbA1c were -0.29% for placebo versus -1.04% and -1.11% for dapagliflozin 5 and 10 mg, respectively (P < 0.0001 for both doses). Changes in fasting plasma glucose were 2.5, -25.1, and -31.6 mg/dL (0.14, -1.39, and -1.75 mmol/L) for placebo, dapagliflozin 5 mg, and dapagliflozin 10 mg. Changes in 2-hour postprandial glucose were 1.1, -46.8, and -54.9 mg/dL (0.06, -2.60, and -3.05 mmol/L). Reductions in body weight were -0.27, -1.64, and -2.25 kg. Proportions of patients achieving HbA1c levels <7.0% (53 mmol/mol) were 21.3%, 42.6%, and 49.8%. Adverse events (AEs) occurred in 63.6%, 61.7%, and 60.9% of patients, and serious AEs occurred in 1.5%, 3.9%, and 3.0% of patients. No deaths occurred. Hypoglycemia was uncommon (1.5%, 0.8%, and 0.8%); no hypoglycemic event led to discontinuation. Genital infections occurred in 0.8%, 3.1%, and 4.5% of patients and urinary tract infections in 3.0%, 3.9%, and 5.3% of patients. No AEs of renal infection or pyelonephritis were reported. No changes in renal function or AEs of renal failure occurred.

Conclusions: Compared with placebo, dapagliflozin 5 and 10 mg demonstrated clinically and statistically significant improvements in HbA1c levels after 24 weeks of treatment. Dose-dependent, statistically significant reductions in fasting plasma glucose, postprandial glucose, and weight were also observed for both doses compared with placebo. AEs and serious AEs were balanced across groups, with low rates of hypoglycemia and no increase in renal events. Genital infections and urinary tract infections were more common with dapagliflozin. Dapagliflozin as monotherapy in these drug-naive Asian patients was well tolerated, significantly improving glycemic control with the additional benefit of weight loss.