A Research Study to See How Much CagriSema Lowers Blood Sugar and Body Weight Compared to Placebo in People With Type 2 Diabetes Treated With Diet and Exercise

Efficacy and Safety of Co-administered Cagrilintide and Semaglutide (CagriSema) s.c. in Doses 2.4 mg/2.4 mg and 1.0 mg/1.0 mg Once Weekly Versus Placebo in Participants With Type 2 Diabetes Inadequately Controlled on Diet and Exercise

This study will look at how much CagriSema helps participants with type 2 diabetes lower their blood sugar and body weight. CagriSema is a new investigational medicine. Doctors may not yet prescribe CagriSema. CagriSema will be compared to a "dummy" medicine (also called "placebo") that has no effect on the body. Participants will get either CagriSema or "dummy" medicine. Which treatment participants get is decided by chance. For each participant, the study will last for about one year.

Inclusion Criteria:

• Male or female
• Age 18 years or above at the time of signing the informed consent
• Diagnosed with type 2 diabetes >=30 days before screening
• HbA1c 7.0-9.5 percent (53-80 millimoles per mole [mmol/mol]) (both inclusive) as determined by central laboratory at screening
• Body mass index (BMI) >=23 kilograms per square meter (kg/m^2) at screening. BMI will be calculated in the electronic case report form (eCRF) based on height and body weight at screening

Exclusion Criteria:

• Female who is pregnant, breast-feeding or intends to become pregnant or is of childbearing potential and not using a highly effective contraceptive method
• Renal impairment with estimated Glomerular Filtration Rate less than 30 milliliter per minute per 1.73 square meter (ml/min/1.73 m^2) as determined by central laboratory at screening
• Treatment with any medication for the indication of diabetes or obesity 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
• History of use of any injectable therapy for diabetes or obesity. 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. Verified by a fundus examination performed within 90 days before screening or in the period between screening and randomisation. Pharmacological pupil-dilation is a requirement unless using a digital fundus photography camera specified for non-dilated examination