The effects of ertugliflozin on ß-cell function: Pooled analysis from four phase 3 randomized controlled studies.

ABSTRACT

AIM: To identify potential predictors and mediators of changes in ß-cell function in response to ertugliflozin treatment in people with type 2 diabetes mellitus (T2DM). PARTICIPANTS AND METHODS: Data from patients with T2DM randomized to ertugliflozin (5 or 15 mg; observations from both doses were pooled) or placebo in four phase 3 clinical studies (clinicaltrials.gov NCT01958671, NCT02226003, NCT02036515, NCT02099110) were pooled and analysed. Change from baseline in ß-cell function at week 26 was assessed, and its potential predictors and mediators were analysed using linear and multiple regression analyses. RESULTS: Compared with placebo, ertugliflozin improved ß-cell function when assessed by mean percent change from baseline in homeostatic model assessment of ß-cell function (HOMA-%ß; ertugliflozin 14.7%, 95% confidence interval [CI] 12.3, 17.1; placebo -0.4%, 95% CI -3.4, 2.5], but not when assessed by change in C-peptide index following a mixed meal tolerance test. Change in HOMA-%ß correlated with change from baseline in glycated haemoglobin (HbA1c) and treatment with ertugliflozin, and weakly with change from baseline in body weight. In the ertugliflozin group, change in HOMA-%ß correlated with baseline fasting plasma glucose (FPG; r = 0.235, P < 0.001), baseline HbA1c (r = 0.138, P < 0.001), baseline homeostatic model assessment of insulin resistance (HOMA-IR; r = 0.162, P < 0.01), and baseline HOMA-%ß (r = -0.321, P < 0.001) in linear regression analyses. Multiple regression analyses yielded similar results. DISCUSSION: In people with T2DM, ertugliflozin treatment improved fasting ß-cell function, but no effect on postprandial ß-cell function was observed in this analysis. Improvement in HOMA-%ß was predicted by high baseline FPG, HbA1c, HOMA-IR, and low baseline HOMA-%ß, and mediated by ertugliflozin treatment, and improved HbA1c and body weight.