This study will look at a new medicine, called IcoSema, for treatment of type 2 diabetes.

IcoSema is a combination of a new insulin, called insulin icodec, and a GLP-1 receptor analogue, called semaglutide.

Insulin icodec is a possible new medicine. That means that the medicine has not yet been approved by the authorities. Semaglutide is a medicine already approved by the authorities in the EU, USA, China and Japan.

The study will look at the way insulin icodec and semaglutide reach and stay in participants blood after injection when given together as IcoSema or alone as insulin icodec and semaglutide.

Participants will get each of the 3 medicines (IcoSema, insulin icodec and semaglutide) at 3 different timepoints:

The order in which participants get them is decided by chance. Participants will get the 3 medicines as an injection under the skin in the thigh. The injections will be done by study staff. The time between injections is 6 to 9 weeks.

The study will last for about 19 to 26 weeks. Participants will have 31 or 32 visits to the clinic. 3 of the visits will be in-house visits, meaning that participants will stay at the clinic for 5 or 6 days (4 or 5 nights).

Women cannot take part if pregnant, breast-feeding or plan to get pregnant during the study period.

Inclusion Criteria:

• Chinese male or female

• Aged 18-64 years (both inclusive) at the time of signing informed consent

• Diagnosed with type 2 diabetes mellitus greater than or equal to 180 days prior to the day of screening

• Body mass index between 18.5 and 34.9 kg/m^2 (both inclusive)

• Body weight greater than or equal to 50 kg

• HbA1c (glycated haemoglobin) below or equal to 9.0% (75 mmol/mol)

• Insulin naïve. However, short-term insulin treatment for a maximum of 14 days prior to the day of screening is allowed, as is prior insulin treatment for gestational diabetes

• Stable daily dose(s) including any of the following anti-diabetic drug(s)/regimen within 45 days prior to the day of screening:

  • Any metformin formulation
  • DPP-4 (dipeptidyl peptidase-4) inhibitors (participants are not allowed to participate in the study if they are treated with DPP-4 inhibitors as monotherapy)
  • SGLT2 (sodium-glucose linked transporter 2) inhibitors
  • Alpha-glucosidase inhibitors
  • Oral combination products (for the allowed individual oral antidiabetic drugs)

Exclusion Criteria:

• Known or suspected hypersensitivity to trial product(s) or related products
• Female who is pregnant, breast-feeding or intends to become pregnant or is of child-bearing potential and not using highly effective contraceptive method
• Uncontrolled and potentially unstable diabetic retinopathy or maculopathy. Verified by a fundus examination performed within 90 days prior to 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
• Recurrent severe hypoglycaemia (more than 1 severe hypoglycaemic event within the past 180 days) or hypoglycaemic unawareness as judged by the investigator or hospitalisation for diabetic ketoacidosis within the past 180 days prior to the day of screening

"According to the Novo Nordisk disclosure commitment on novonordisk-trials.com"

Sponsor staff involved in the clinical trial is masked according to company standard procedures