 This is a multicenter randomized controlled study.This study will recruit adult age 340 years type 2 diabetes patients who is on metformin 31500mgday currently with recent HbA1c between 7.08.5.Patient who has history of macular edema, congestive heart failure NYHA Fc III, IV, chronic renal failure stage IV, V, AST or ALT above 2.5 times upper limit, Medical history of endocrinopathies, osteoporosis with bone fracture, cancer will be excluded. Current bone fracture undergoing treatment, pregnancy, breast feeder will also be excluded. 