Dual Action of Liraglutide and Insulin Degludec in Type 2 Diabetes: A Trial Comparing the Efficacy and Safety of Insulin Degludec/Liraglutide, Insulin Degludec and Liraglutide in Subjects With Type 2 Diabetes

Inclusion Criteria: * Subjects with type 2 diabetes * HbA1c 7.0-10.0 % (both inclusive) with the aim of a median HbA1c of 8.3%. Accordingly, when approximately 50% of the randomised subjects have a HbA1c above 8.3%, the remaining subjects randomised must have a HbA1c of below or equal to 8.3%, or when approximately 50% of the randomised subjects have a HbA1c of below or equal to 8.3%, the remaining subjects randomised must have a HbA1c above 8.3% * Male or female, age 18 years or above (Taiwan: 20 years or above for a site 653 in Taiwan: Taichung Veterans General Hospital) * Subjects on stable dose of 1-2 OADs (metformin \[at least 1500 mg or max tolerated dose\] or metformin \[at least 1500 mg or max tolerated dose\] + pioglitazone \[at least 30 mg\]) for at least 90 days prior to screening * Body Mass Index (BMI) maximum 40 kg/m\^2 Exclusion Criteria: * Treatment with insulin (except for short-term treatment due to intercurrent illness at the discretion of the Investigator) * Treatment with GLP-1 (glucagon-like peptide-1) receptor agonists (eg exenatide, liraglutide), sulphonylurea or dipeptidyl peptidase 4 (DPP-4) inhibitors within 90 days prior to trial * Impaired liver function, defined as alanine aminotransferese (ALAT) at least 2.5 times Upper Normal Range (UNR) (one retest analysed at the central laboratory within a week from first sample taken is permitted with the result of the last sample being the conclusive) * Impaired renal function defined as serum-creatinine at least 133 mcmol/l (at least 1.5 mg/dl) for males and at least 125 mcmol/l (at least 1.4) for females, or as allowed according to local contraindications for metformin (one retest analysed at the central laboratory within a week from first sample taken is permitted with the result of the last sample being the conclusive) * Screening calcitonin at least 50 ng/L * Subjects with personal or family history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia type 2 (MEN 2) * Cardiac disorder defined as: congestive heart failure (NYHA class III-IV), diagnosis of unstable angina pectoris, cerebral stroke and/or myocardial infarction within the last 12 months and planned coronary, carotid or peripheral artery revascularisation procedures * Severe uncontrolled treated or untreated hypertension (systolic blood pressure at least 180 mm Hg or diastolic blood pressure at least 100 mm Hg) * Acute treatment required proliferative retinopathy or maculopathy (macular oedema) * History of chronic pancreatitis or idiopathic acute pancreatitis