The primary objective of this study is to evaluate the long-term safety of ASP1941 in patients with type 2 diabetes mellitus. The second objectives are to compare the efficacy and pharmacokinetics of ASP1941 administered before or after food intake.

Subject will be randomized into either ASP1941 before meal or ASP1941 after meal groups. Subjects will undergo a screening period before entering the long-term treatment. Dosage may be increased during the treatment period if subjects fulfill increasing criteria and the investigators adjudicate that no impact for subjects safety.

Inclusion Criteria:

• Type 2 diabetic patients for at least 12 weeks
• HbA1c value between 6.5 and 9.5%
• Body Mass Index ( BMI )20.0 - 45.0kg/m2

Exclusion Criteria:

• Type 1 diabetes mellitus patients
• Serum creatinine > upper limit of normal
• Proteinuria (albumin/creatinine ratio > 300mg/g)
• Dysuria and/or urinary tract infection, genital infection
• Significant renal, hepatic or cardiovascular diseases
• Severe gastrointestinal diseases
• Proliferative diabetic retinopathy

Access to anonymized individual participant level data will not be provided for this trial. Further details on Astellas' data sharing policy can be found at https://www.clinicaltrials.astellas.com/transparency/.