Insulin Pump to Multiple Daily Injection Transition Clinical Trial

Inclusion Criteria: 1. Age ≥18 years and ≤ 65 years 2. Patients with T1D diagnosed for at least 12 months 3. Point-of-care HbA1c levels between ≥6.5% and ≤ 8.5% 4. Patients on CSII (any insulin pump) for at least past 6 months 5. Willing and able to wear a blinded CGM during the time of study period 6. Willing to perform self-monitoring of blood glucose (SMBG) at least 4 times a day 7. Ability to provide informed consent before any trial-related activities 8. Not willing to or plan any travel out of Colorado during the 3 weeks of study period 9. Willing to use insulin degludec in the morning once a day Exclusion Criteria: 1. Age \<18 years and \> 65years 2. HbA1c \>8.5 % at screening 3. Less than 12 months of insulin treatment 4. Patients on 670G or Tandem Control IQ (Medtronic and Tandem Hybrid Closed-loop systems) and not willing use manual mode during the study period 5. Patients with T1D using any glucose lowering medications other than insulin 6. Pregnancy, breast feeding, and positive pregnancy test during screening 7. Women of childbearing age wanting to become pregnant or not using adequate contraceptive measures 8. Current or recent (\< 2 weeks prior to visit 1) use of any steroidal medication, or anticipated steroidal treatment, during the study period 9. eGFR below 45 ml/min/1.73 m\^2 using MDRD formula 10. History of severe hypoglycemia in the previous 3 months 11. History of diabetic ketoacidosis (DKA) requiring hospitalization in the past 3 months 12. History of allergy to any form of insulin or its excipients 13. History of allergy to adhesives 14. Unwilling to use blinded CGM during the study period 15. Unwilling to perform SMPG at least 4 times a day 16. Known history of alcohol abuse or illicit drug use within 6 months prior to screening 17. Use of investigational drugs within 5 half-lives prior to screening 18. Participation to other study trials during the study period 19. Elevated liver enzymes (AST and ALT) 3 times the upper limit of normal 20. Hypoglycemia unawareness defined as GOLD score ≥4 \[20\] 21. Any comorbidities or medical conditions that make a person unfit for the study at the discretion of the investigators 22. Anticipated travel across different time zones (difference greater than 4 hours) or anticipated change in physical activities or diet at the discretion of the investigators.