A Trial Investigating the Effect of Oral Semaglutide Compared With Placebo on Postprandial Glucose and Triglyceride Metabolism, Energy Intake, Appetite Sensations and Gastric Emptying in Subjects With Type 2 Diabetes

Inclusion Criteria: * Male or female, aged 18-75 years (both inclusive) at the time of signing informed consent * Subjects diagnosed with type 2 diabetes mellitus for at least 90 days prior to the day of screening. * Treated with diet and exercise and/or metformin monotherapy. The metformin dose should be unchanged in a period of 30 days prior to screening * Body mass index (BMI) between 20.0-38 kg/m\^2 (both inclusive) * HbA1c (glycosylated haemoglobin) between 6.0-9.0 % (both inclusive) Exclusion Criteria: * Female who is pregnant, breast-feeding or intends to become pregnant or is of child-bearing potential and not using adequate contraceptive methods (adequate contraceptive measures as required by local regulation or practice) * Family or personal history of Multiple Endocrine Neoplasia Type 2 or Medullary Thyroids Carcinoma * History of pancreatitis (acute or chronic) * Presence of clinically significant or symptoms of gastrointestinal disorders potentially affecting absorption of drugs and/or nutrients, as judged by the investigator * History of major surgical procedures involving the stomach potentially affecting absorption of trial product (e.g. subtotal and total gastrectomy, sleeve gastrectomy, gastric bypass surgery) * History or presence of any clinically relevant respiratory, metabolic (including dyslipedimia, however mild dyslipidaemia, defined as screening total cholesterol below or equal to 7.8 mmol/L and screening triglyceride below or equal to 3.42 mmol/L is accepted), renal, hepatic, gastrointestinal, endocrinological conditions (except conditions associated with diabetes mellitus) * History or presence of malignant neoplasms within the last 5 years (except basal and squamous cell skin cancer and in-situ carcinomas) * History or presence of cardiovascular disease including stable and unstable angina, myocardial infarction, transient ischaemic attack, stroke, cardiac decompensation, clinically significant arrhythmias and conduction disorders * Renal impairment with estimated Glomerular Filtration Rate (eGFR) below 60 mL /min as defined by CKD-EPI using IDMS for serum creatinine measurement on the day of screening * Impaired liver function, defined as ALT above or equal to 2.5 times upper normal limit (UNL) on the day of screening * Smoker (defined as a subject who is smoking more than 1 cigarette or the equivalent per day). During the in-patient period, the subject must be willing to completely refrain from smoking and use of nicotine substitute products * Known or suspected alcohol abuse within 1 year from screening (defined as regular intake of more than 21 units weekly for men and 14 units weekly for women - one unit of alcohol equals about 300 mL of beer or lager, one glass (100 mL) of wine, or 25 mL spirits)