A Research Study Comparing How Well Different Doses of the Medicine NNC0662-0419 Lower Blood Sugar in People With Type 2 Diabetes

This study is being done to look at the effect and safety of different doses of NNC0662-0419 in people living with type 2 diabetes when compared to placebo or semaglutide. The purpose of this clinical study is to find out if NNC0662-0419 is effective and safe for treating people living with type 2 diabetes. Participants will get either NNC0662-0419, semaglutide or placebo. Which treatment participants get is decided by chance. NNC0662-0419 is a new medicine which cannot be prescribed by doctors but has previously been tested in humans. Semaglutide is an approved medication to treat type 2 diabetes.

Inclusion criteria * Male or female (sex at birth). * Age 18-75 years (both inclusive) at the time of signing the informed consent. * Glycated haemoglobin (HbA1c) of 7.0-10.0 percent (%) (53-86 millimoles per mole \[mmol/mol\]) (both inclusive) as assessed by central laboratory at screening. * Willingness to obtain a high weight loss (greater than \[\>\] 25% of weight at baseline). Exclusion criteria * Treatment with any medication for the indication of diabetes or obesity other than stated in the inclusion criteria within 90 days before screening. However, short term insulin treatment for a maximum of 14 consecutive days and prior insulin treatment for gestational diabetes are allowed. * Uncontrolled and potentially unstable diabetic retinopathy or maculopathy. Pharmacological pupil-dilation is a requirement unless using a digital fundus photography camera specified for non-dilated examination. * Known hypoglycaemic unawareness as indicated by the investigator according to Clarke's Questionnaire.