Research Study in Japan to Compare Dasiglucagon With Glucagon in Treating Very Low Levels of Blood Sugar in Asian Adults With Type 1 Diabetes and Testing of Dasiglucagon for the Same Condition in Japanese Adolescents

Inclusion criteria

• For Adults: Asian male or female; For Adolescents: Japanese male or female.
• Age at the time of signing the informed consent:

For Adults: Age 18-75 years (both inclusive):

For Adolescents: Age 12-15 years (both inclusive).

• Diagnosed with T1D greater than (>)1 year before screening.
• Glycated haemoglobin (HbA1c) less than (<)10.0 percentage (%) (86 millimoles per mole [mmol/mol]) as assessed by subcontracted laboratory by the site on the day of screening.
• For adults: BMI between 18.5 and 29.9 kilogram per meter square (kg/m2) (both inclusive).

For adolescents: Body weight greater than or equal to (≥) 33.4 kilograms (kg).

• Treated with stable insulin treatment (based on the investigator's discretion preferably no more than a 10-unit daily variation in total daily insulin dose) 30 days prior to screening.
• For Japanese participants: Japanese passport or equivalent For non-Japanese participants: Asian (non- Japanese passport or equivalent).

Exclusion criteria

• Known or suspected hypersensitivity to study intervention(s) or related products (glucagon or its derivatives).
• Exposure to an investigational medicinal product (IMP) within 30 days or 5 times the half-life of the IMP (if known), whichever is longest before screening.
• Severe hypoglycaemia in the last month prior to screening.
• Hospitalisation for diabetic ketoacidosis (DKA) in the last month prior to screening.
• Presence or history of any clinically relevant respiratory, metabolic, renal, hepatic, gastrointestinal, endocrinological conditions (except conditions associated with diabetes mellitus).
• History of epilepsy or seizure disorder.
• Known presence or history of pheochromocytoma (i.e., adrenal gland tumour) or insulinoma (i.e., insulin-secreting pancreas tumour).
• Clinically significant abnormal electrocardiogram (ECG) at screening as evaluated by investigator.
• Any disorder, unwillingness or inability which in the investigator's opinion, might jeopardise the participant's safety or compliance with the protocol.

As declared by the participant or in the medical records.