A Trial Comparing the Efficacy and Safety of Insulin Degludec/Liraglutide Versus Insulin Glargine in Subjects With Type 2 Diabetes Mellitus

Inclusion Criteria: - Type 2 diabetes mellitus - HbA1c 7.0-10.0% [53-86 mmol/mol] (bothinclusive) by central laboratory analysis - Current treatment with insulin glargine for atleast 90 days prior to screening - Stable daily dose of insulin glargine between 20 unitsand 50 units (both inclusive) for at least 56 days prior to screening. Total daily doseshould be within the range of 20-50 units, both inclusive, on the day of screening, butindividual fluctuations of plus/minus 10 procent within the 56 days prior to screening areacceptable - Stable daily dose of metformin (above or equal to 1500 mg or max tolerateddose) for at least 90 days prior to screening - Body mass index (BMI) below or equal to 40

kg/m^2 Exclusion Criteria: - Any use of oral antidiabetic agents (OADs) (except formetformin) within 90 days prior to Visit 1 (screening) - Current use of any drug (exceptmetformin and insulin glargine) or anticipated change inconcomitant medication, which inthe investigator's opinion could interfere with the glucose metabolism (e.g. systemiccorticosteroids) - Previous and/or current treatment with any insulin regimen other thanbasal insulin, e.g. prandial or pre-mixed insulin (short term treatment due to intercurrentillness includinggestational diabetes is allowed at the discretion of the investigator) -Previous and/or current treatment with glucagon-like peptide-1 (GLP-1) receptor agonists (e.g. exenatide, liraglutide) - Impaired liver function, defined as ALAT (alanineaminotransferase) above or equal to 2.5 times upper normal range (UNR) - Impaired renalfunction defined as serum-creatinine above or equal to 133 micromol/L (above or equal to 1.5 mg/dL) for males and above or equal to 125 micromol/L (1.4 mg/dL) for females, or asallowed according to local contraindications for metformin - Screening calcitonin above orequal to 50 ng/L - Personal or family history of medullary thyroid carcinoma (MTC) ormultiple endocrine neoplasia type 2 (MEN2) - History of chronic pancreatitis or idiopathicacute pancreatitis