A Research Study to See How Much CagriSema Lowers Blood Sugar and Body Weight Compared to Placebo in Children and Adolescents With Type 2 Diabetes

Key Inclusion Criteria: * Informed consent of parent(s) or legally acceptable representative (LAR) of participant and child assent, as age-appropriate, obtained before any study-related activities. Study-related activities are any procedures that are carried out as part of the study, including activities to determine suitability for the study. * The parent(s) or LAR of the child must sign and date the Informed Consent Form (according to local requirements) * The child must sign and date the Child Assent Form or provide oral assent (according to local requirements) * Male or female. * Age 10 to \< 18 years at the time of signing the informed consent. * Diagnosed with T2D (according to the latest International Society for Pediatric and Adolescent Diabetes \[ISPAD\] criteria) ≥ 30 days before screening. * Treated with diet and exercise counselling alone or with a stable daily dose(a), in addition to diet and exercise counselling, of any of the following antidiabetic drugs or combination regimens: * Insulin (any regimen) * Metformin * SGLT2i * HbA1c 6.5%-11.0% (48 mmol/mol - 97 mmol/mol) (both inclusive) as determined by central laboratory at screening. * Body weight ≥ 45 kg and BMI ≥ 85th percentile(b). BMI will be calculated in the electronic case report form based on height and body weight at screening. * (a) For metformin, a stable dose is defined as at least 1000 mg daily or the maximum tolerated dose for ≥ 56 days prior to screening. For Sodium-Glucose Trans…