Efficacy and Safety Study of Empagliflozin as add-on to Insulin in Japanese Patients With Type 2 Diabetes Mellitus

Inclusion criteria: * Diagnosis of type 2 diabetes mellitus * Patients on diet and exercise regimen who are pre-treated with any insulin therapy alone or in combination with 1 oral antidiabetic drug for at least 12 weeks prior to screening * Fasting C-peptide must be \> 0.5 ng/mL * HbA1c at screening in Patients who are treated with insulin alone must be \>=7.5% and \<=10.0% * HbA1c in Patients who are treated with insulin with 1 oral antidiabetic drug (OAD) must be \>=7.0% and \<=9.5% at screening, and \>=7.5% and \<=10.0% at placebo run-in period * Age at informed consent must be \>=20 and \<75 years * BMI at screening must be \>22 and \<=40 kg/m2 * Further inclusion criteria apply Exclusion criteria: * Patients who experience uncontrolled hyperglycaemia before randomization * Patients who are treated with sulfonylurea whose dose is more than a half of daily maximum approval dose, glucagon-like peptide-1 (GLP-1) analogue, thiazolidinedione and sodium-glucose co-transporter 2 (SGLT-2) inhibitor * Patients with recent cardiovascular and/or stroke events * Patients with hepatic and/or renal dysfunction * Patients who received anti-obesity drugs or other treatment leading to unstable body weight * Patients who have known allergy or hypersensitivity to insulin and/or empagliflozin * Pre-menopausal women who are nursing or pregnant * Further exclusion criteria apply