Evaluation of Extended Wear Infusion Set With 670G Hybrid Closed-Loop Therapy

Inclusion Criteria:

   1. Clinical diagnosis of type 1 diabetes for more than one year, using an insulin
   infusion pump for at least 6 months, and using the 670G pump for at least 3 months

   2. Age ≥18 years

   3. Using Novolog or Humalog insulin at time of enrollment

   4. For females, not currently known to be pregnant

   5. An understanding of and willingness to follow the protocol and sign the informed
   consent

   6. Willing to have photographs taken of their infusion sites

   7. Willing to download their 670G pump every week to a research Carelink account

   8. Willing to submit a brief online questionnaire at the time of any infusion set failure

   9. Able to understand spoken or written English

10. Hemoglobin A1c <8.5% at the time of enrollment

11. Willing to perform three or more fingerstick glucose measurements each day

12. Willing to sign a consent for release of medical information at the time of enrollment

13. Willing to change their infusion pump insulin reservoirs at least every 6 days

Exclusion Criteria:

   1. Hypoglycemic seizure or loss of consciousness in the past 6 months

   2. Severe episode of DKA in the 6 months prior to study enrollment that was unrelated to
   an infusion set failure

   3. A known cardiovascular disease

   4. Active proliferative diabetic retinopathy

   5. Known tape allergy

   6. Current treatment for a seizure disorder

   7. Cystic fibrosis

   8. Active infection

   9. A known medical condition that in the judgment of the investigator might interfere
   with the completion of the protocol

10. Inpatient psychiatric treatment in the past 6 months

11. Presence of a known adrenal disorder

12. If on antihypertensive, thyroid, anti-depressant or lipid lowering medication, lack of
   stability on the medication for the last 2 months prior to enrollment in the study

13. Abuse of alcohol

14. History of dialysis, renal failure or known eGFR <60 ml/min/1.73m2

15. Has received a blood transfusion or required treatment for anemia in the three months
   prior to enrollment