Comparison of efficacy of ipraglifrozine and high-dose metformin in patients with type 2 diabetes

INTERVENTION: arm metformine:increase the dose of metformine from 750 mg/day to 1500 mg/day or from 500mg/day to 1000mg/day and observe for 52 weeks arm ipraglyfrozine:add 50 mg of ipraglyfrozine on 750 mg/day of metformine and observe for 52 weeks CONDITION: D003924 Diabetes Mellitus, Type 2 ; Diabetes Mellitus, Type 2 PRIMARY OUTCOME: The amount of change in HbA1c before and after the study SECONDARY OUTCOME: safety and body weight, blood pressure, changes in various blood / urine tests INCLUSION CRITERIA: 1. age>=20, <75 2. HbA1c>=6.5%, <10% 3. treated by 500‐750 mg/day of metformine in addition to diet and exercise therapy 4. no need for additional drug for hypertension or dyslipidemia 5. written informed consent obtained