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): 12.0-70.0,  Type 1 Diabetes Mellitus Clinical diagnosis of type 1 diabetes for at least 1 year. For an individual to be enrolled at least one criterion from each list must be met: for documented hyperglycemia (at least 1 must be met): 1. Fasting glucose ≥126 mg/dL (confirmed) 2. Two-hour oral glucose tolerance test (OGTT) glucose ≥200 mg/dL (confirmed) 3. HbA1c ≥6.5% (confirmed) 4. Random glucose ≥200 mg/dL with symptoms 5. No data at diagnosis is available but the participant has a convincing history of hyperglycemia consistent with diabetes or in the opinion of the investigator participant has history consistent with type 1 diabetes. for requiring insulin at diagnosis (at least 1 must be met): 1. Participant required insulin at diagnosis and continually thereafter 2. Participant did not start insulin at diagnosis but upon investigator review likely needed insulin (significant hyperglycemia that did not respond to oral agents) and did require insulin eventually and used continually 3. Participant required insulin at diagnosis but continued to be hyperglycemic, had positive islet cell antibodies consistent with latent autoimmune diabetes in adults (LADA) and did require insulin eventually and used continually thereafter Use of insulin for the last 12 months or more Use of an insulin infusion pump for the last 6 months or longer Age 12-70 years old HbA1c <10.0% as measured with DCA2000 or equivalent device; if HbA1c <6.0% then total daily insulin must be ≥0.5 U/kg Risk of hypoglycemia or hypoglycemia unawareness as defined by any of the following Clarke Hypoglycemia Perception Awareness questionnaire score of ≥4 Average Daily Risk Range (ADRR) >40 as assessed from Self-Monitoring Blood Glucose (SMBG) readings from the prior month. Subject must have a glucometer that can be downloaded for this assessment. The subjects may alternatively provide a spreadsheet of their past 30 days of blood glucose values Low Blood Glucose Index (LBGI) >2.5 as assessed from SMBG from the prior month or LBGI >1.1 as assessed from 1 week of CGM readings from the prior three weeks. Subject must have a glucometer or CGM that can be downloaded for this assessment. For the glucometer data, the subjects may alternatively provide a spreadsheet of their past 30 days of blood glucose values  The presence of any of the following is an for the study: 1. Admission for diabetic ketoacidosis in the 12 months prior to enrollment. 2. Severe hypoglycemia resulting in seizure or loss of consciousness in the 3 months prior to enrollment. 3. Hematocrit less that the lower limit of normal for the assay. 4. Pregnancy, breast-feeding, or intention of becoming pregnant over time of study procedures; If female and sexually active, must agree to use a form of contraception to prevent pregnancy while a participant in the study. A negative urine pregnancy test will be required for all premenopausal women who are not surgically sterile. Subjects who become pregnant will be discontinued from the study. 5. Conditions which may increase the risk of induced hypoglycemia such as: known coronary artery disease, congestive heart failure, history of any cardiac arrhythmia (benign premature atrial contractions and premature ventricular contractions allowed), history of seizure disorder, history of cerebrovascular event or transient ischemic attack, hypoglycemia-induced migraine within the last 6 months, or neurological disease. 6. Cystic fibrosis 7. A known medical condition that in the judgment of the investigator might interfere with the completion of the protocol such as the following examples: 8. Inpatient psychiatric treatment in the past 6 months for either the subject or the subject's diabetes care partner 9. Presence of a known adrenal disorder 10. Abnormal liver function tests (transaminase >3 times the upper limit of normal); testing required for subjects taking medications known to affect liver function or with diseases known to affect liver function 11. Abnormal renal function test results (estimated Glomerular filtration rate (GFR) <60 mL/min/1.73m2); testing required for subjects with diabetes duration of greater than 5 years post onset of puberty 12. Active gastroparesis 13. If on antihypertensive, thyroid, anti-depressant or lipid lowering medication, lack of stability on the medication for the past 2 months prior to enrollment in the study 14. Uncontrolled thyroid disease (TSH undetectable or >10 mIU/L); testing required within 3 months prior to admission for subjects with a goiter, positive antibodies, or who are on thyroid hormone replacement, and within one year otherwise 15. Current or recent abuse of alcohol or recreational drugs by patient history 16. Infectious process not anticipated to resolve prior to study procedures (e.g. meningitis, pneumonia, osteomyelitis) 17. Any skin condition in the area of insertion that prevents safe sensor or pump placement (e.g. bad sunburn, pre-existing dermatitis, intertrigo, psoriasis, extensive scarring, cellulitis) 18. Diagnosed with celiac disease and not currently following a gluten free diet A recent injury to body or limb, muscular disorder, use of any medication, any carcinogenic disease, or other significant medical disorder if that injury, medication, or disease in the judgment of the investigator will affect the completion of the protocol Current use of any of the following drugs and supplements: 19. Any medication being taken to lower blood glucose, such as Pramlintide, Metformin, Glucagon-like peptide-1 (GLP-1) Analogs such as Liraglutide, and nutraceuticals intended to lower blood glucose 20. Beta blockers 21. Oral glucocorticoids 22. Pseudoephedrine 23. Any other medication that the investigator believes is a contraindications to the subject's participation