Comparison of Insulin Degludec With Insulin Glargine U100 for Adults With Type 1 Diabetes Crossing Multiple Time Zones.

Inclusion Criteria: 1. Males or females ≥18 and ≤65 years of age. 2. Type 1 diabetes mellitus (diagnosed clinically and treated with multiple daily injections of insulin) for ≥12 months. 3. HbA1c \<10% within 30 days of being enrolled in the study 4. Current treatment with any basal insulin analogue as the once daily basal insulin given in the evening (22) and no fewer than three injections with rapid acting bolus insulin (e.g. insulin aspart, insulin lispro, or insulin glulisine) as mealtime bolus insulin therapy. 5. No contraindication to long-haul travel. 6. No recurrent severe hypoglycemia (more than 1 severe hypoglycemic event requiring hospitalization during the last 12 months), or hypoglycemia unawareness as judged by a score of \>4 on the Gold score (23), or hospitalization for diabetic ketoacidosis during the previous 6 months. 7. Willing and able to use a continuous glucose monitoring device (e.g. Dexcom G4). 8. Ability to self-manage insulin therapy (verbal confirmation at screening visit) of a changed bolus insulin dose the preceding 2 months prior to screening. 9. Ability and willingness to adhere to the protocol, including performance of self-monitored blood glucose (SMBG) readings and self-adjustment of insulin doses according to protocol. \- Exclusion Criteria: 1. Current use of an insulin pump. 2. Use within the last 3 months prior to enrollment visit 1 of any glucose-lowering drug other than insulin. 3. Initiation or significant change of any systemic treatment which, in the investigator's opinion, could interfere with glucose metabolism, such as systemic corticosteroids, beta-blockers or monoamine oxidase inhibitors (inhaled corticosteroids allowed). 4. Proliferative retinopathy or maculopathy requiring treatment, according to the investigator. 5. Pregnancy, breast-feeding, the intention of becoming pregnant or not using adequate contraceptive measures. 6. Any clinically significant disease or disorder, which in the investigator's opinion could interfere with the results of the trial. 7. Mental incapacity, psychiatric disorder, unwillingness or language barriers precluding adequate understanding or cooperation, including subjects not able to read or write, and known or suspected abuse of alcohol, narcotics, or illicit drugs. 8. Known or suspected allergy to any of the trial products or related products. 9. Receipt of any investigational drug or participation in other trials within 1 month prior to Visit 1. \-