A multicenter, randomized, double-blind, parallel group, placebo-controlled, phase 3 study to evaluate the efficacy and safety of the combination of A51R3 and AJU-A51 compared with the combination of A51R3 and A51R2 in patients with Type 2 diabetes mellitus who have inadequate glycemic control with the combination of A51R3 and A51R2

Inclusion Criteria:

• Those who voluntarily signed the informed consent to participate in this study.
• Adults aged 19-75 years.
• Those diagnosed with type 2 diabetes mellitus.
• 7% ≤ HbA1c ≤ 10.5%
• FPG ≤ 270 mg/dL
• BMI ≤ 40 kg/㎡
• Subjects able to understand the study, comply with study procedures, and attend all scheduled visits.

Exclusion Criteria:

• Those who suffered from acute or chronic metabolic acidosis, lactic acidosis and diabetic ketoacidosis.
• Those who had genetic disorders such as galactose intolerance, Lapp lactose deficiency, or glucose-galactose malabsorption.
• Those with heart failure (NYHA class II~IV) or who had suffered from heart failure.
• Those with a history of malignant tumor within 5 years
• Those who have a clinically significant liver disease
• Those who have a clinically significant renal disease
• SBP > 180 mmHg or DBP > 110 mmHg
• Those who had allergic reaction to main ingredients or components of the investigational products.
• Patients planning to become pregnant or of childbearing potential, but not using any recognized contraceptive method
• Females who are pregnant or breastfeeding.
• AST or ALT ≥ LRN*3
• TG ≥ 500 mg/dL