Patient description: The patient is a 24-year-old man who has had type 1 diabetes for 11 years. He presents to the emergency room with hyperglycemia and concern for possible diabetic ketoacidosis after not taking his insulin for 3 days. The patient reports that he is currently homeless and has lost his supply of insulin, syringes, glucometer, and glucose testing supplies. The patient states that at the time of his initial diagnosis with type 1 diabetes he was hospitalized with a glucose value >1000 mg/dL. At the time, he was experiencing polyuria, polydipsia, and polyphagia. He reports that he has been on insulin since the time of his diagnosis, and he has never been prescribed oral agents for diabetes management. Most recently, he has been using insulin glargine 55 units once daily, and insulin aspart sliding scale 3 times daily. The patient has had previous episodes of diabetic ketoacidosis, for which he was hospitalized. With this episode of hyperglycemia, he is not experiencing any nausea, vomiting, or abdominal discomfort, and he appears well. His lab studies showed: A1c: 11.3% Creatinine: 0.9 mg/dL with eGFR >60 mL/min Aspartate aminotransferase (AST): 17 U/L Alanine aminotransferase (ALT): 14 U/L Beta-hydroxybutyrate: 0.1 mmol/L Bicarbonate: 25 mEq/L Anion

Clinical trial eligibility criteria: eligible ages (years): 18.0-75.0,  Type 1 Diabetes Patients must meet ALL to be included in the study. 1. Patient age is 18-75 years. 2. Diagnosis of T1D of at least 1-year duration. 3. Has the ability to provide informed consent before any trial-related activities. 4. Treated with insulin glargine as their basal insulin in the 3 months preceding screening visit. 5. Stable insulin regimen (defined as change of <20% in the total daily dose of insulin and no change to the basal insulin agent) over the 3 months preceding the screening visit. 6. Patient willing to dose their basal insulin at bedtime. 7. Hemoglobin A1c < 9% in the 3 months preceding screening visit. 8. Able to self-administer their insulin doses. 9. Able to do self-monitoring of blood glucose using a glucose meter and willing to do this at least 2 times daily for patients using a CGM that requires calibration prior to the study and 4 times daily for patients who were not using a CGM prior to the study. 10. Agreeable to the use of a continuous glucose monitor (CGM) for the duration required in the study. If already using a CGM prior to the study, then agreeable to wearing the blinded study CGM concurrently during the study period. 11. Will be reachable by phone and/or email to comply with study procedures. 12. Will be able to comply with study procedures, per investigator's opinion. 13. Patient agrees to not use correctional insulin unless BG ≥250 for the 48 hours before and after 1st dose of IDeg  Patient must not have ANY of the to be included in the study. 1. Patients with eGFR <30 on at least 2 measurements within 1-year of the screening visit. 2. History of myocardial infarction within 6 months preceding the screening visit. 3. Patients taking non-insulin medications for the glycemic management of T1D (including metformin, DPP-4 inhibitors, GLP-1 receptor agonists, SGLT-2 inhibitors, thiazolidinediones, alpha-glucosidase inhibitors, pramlintide) 4. Known or suspected allergy to IDeg or one of its excipients. 5. Pregnant, planning to become pregnant in the next 3 months or breastfeeding. 6. Participation in a clinical trial with investigational drug within 1 month of the screening visit or at present. 7. Skin condition that prevents the insertion of the CGM. 8. Previously randomized and received drug in this study. 9. Presence of decompensated or poorly controlled psychiatric conditions. 10. Current known or suspected illicit substance use. 11. Any anticipated surgery or procedure in the next 14 days. 12. Patients using U-300 glargine as their basal insulin. 13. Patients using insulin afrezza as their short-acting insulin. 14. Use of glucocorticoid burst/pulse therapy within 14 days prior to screening visit (chronic stable glucocorticoid doses are acceptable)