A Research Study to See How Insulin Icodec Helps People With Type 1 Diabetes Control Their Blood Sugar

Inclusion Criteria:

• Signed consent obtained before any study-related activities (study-relatedactivities are any procedures related to recording of data according to theprotocol).

• The decision to initiate treatment with commercially available insulin icodec hasbeen made by the participant/legally acceptable representative (LAR) and thetreating physician before and independently from the decision to include theparticipant in this study.

• Male or female, age greater than or equal to (≥) 18 years at the time of signinginformed consent.

• Diagnosed with T1D ≥ 1 year before signing informed consent.

• Treated with multiple daily insulin injections (daily basal insulin analogue andbolus insulin analogue regimen) ≥ 6 months before signing informed consent.

• Available HbA1c value less than or equal to (≤) 90 days prior to the 'Initiationvisit' (V1) or HbA1c measurement taken in relation with the 'Initiation visit' (V1)if in line with local clinical practice.

• Treatment naïve to once-weekly insulin prior to the 'Initiation Visit' (V1).

Exclusion Criteria:

• Previous participation in this study. Participation is defined as having giveninformed consent in this study.

• Treatment with any investigational drug within 30 days prior to enrolment into thestudy.

• Mental incapacity, unwillingness or language barriers precluding adequateunderstanding or cooperation.