Safety and Efficacy of Bexagliflozin Compared to Sitagliptin as Add-on Therapy to Metformin in Type 2 Diabetes Subjects

The purpose of this study is to investigate the effect of bexagliflozin compared to sitagliptin as an add-on therapy to metformin in lowering hemoglobin A1c (HbA1c) levels in subjects with type 2 diabetes mellitus (T2DM).

This was a phase 3, multi-center, randomized, double-blind, parallel-group study to demonstrate that bexagliflozin was non-inferior to sitagliptin as add-on therapy in subjects whose T2DM was not adequately controlled by metformin treatment alone. The primary effectiveness endpoint was the change in HbA1c from baseline at week 24. At the time of screening, all subjects were to have taken metformin at a stable dose of ≥ 1500 mg per day for ≥ 8 weeks and have received diet and exercise counseling. A total of 374 eligible subjects were to be enrolled in the study. Subjects who successfully completed a 1-week run-in and who met all eligibility criteria were to be randomized in a 1:1 ratio to receive once daily double-blind treatment of either active bexagliflozin tablets with placebo sitagliptin tablets or placebo bexagliflozin tablets and active sitagliptin tablets. The study subjects were to continue receiving open-labeled metformin during the entire study at a stable dose and frequency. The treatment period was 24 weeks and was conducted in an outpatient setting. Randomization was stratified by HbA1c (≤ 8.5% vs. ˃ 8.5%) values. Symptoms and blood sugars related to the occurrence of hyperglycemia, hypoglycemic events or symptoms that could indicate ketoacidosis were to be recorded. Bexagliflozin tablets, 20 mg or placebo, and sitagliptin tablets, 100 mg or placebo, were to be taken once daily at approximately the same time each day either before or after breakfast. Background metformin was to be taken at the same dose and frequency from screening throughout the entire study. Each subject was advised to return to the clinic at weeks 6, 12, 18 and 24 for efficacy assessment and safety monitoring, including review of AEs and concomitant medication, vital signs, ECG, physical examination and blood and urine specimen collections. Subjects were to return to the clinic for a follow-up exit visit at week 26 or 2 weeks after the last dose of study drugs if subjects withdrew from the study prior to week 24.