Prepivotal Omnipod Horizon™ Automated Glucose Control System

Inclusion Criteria:

   1. Age at time of consent/assent 6-70 years

   2. Subjects aged < 18 years must be living with parent/legal guardian

   3. Diagnosed with type 1 diabetes for at least 6 months. Diagnosis is based on
   investigator's clinical judgment.

   4. Deemed appropriate for pump therapy per investigator's assessment taking into account
   previous history of severe hypoglycemic and hyperglycemic events, and other
   comorbidities

   5. Investigator has confidence that the subject can successfully operate all study
   devices and is capable of adhering to the protocol

   6. Willing to use only the following types of insulin during the study: Humalog, Novolog,
   Admelog, or Apidra during the study

   7. Must be willing to set target glucose between 130-150 mg/dL each for approximately
   72-hours on predefined days during the hybrid closed-loop phase

   8. Must be willing to extend their participation into the pivotal study if they continue
   to meet the protocol criteria

   9. Willing to wear the system continuously throughout the study

10. A1C <10% at screening visit

11. Must be willing to use the Dexcom App on the Omnipod Horizon™ PDM as the sole source
   of Dexcom data (with the exception of the Dexcom Follow App) during the hybrid
   closed-loop phase

12. Subjects scoring ≥ 4 on the Clarke Questionnaire must agree to have an overnight
   companion, defined as someone who resides in the same home or building as the study
   subject and who can be available overnight

13. Able to read and speak English fluently

14. Subject must be in an AT&T covered area

15. Willing and able to sign the Informed Consent Form (ICF) and/or has a parent/guardian
   willing and able to sign the ICF. Assent will be obtained from pediatric and
   adolescent subjects aged < 18 years per State requirements.

Exclusion Criteria:

   1. A medical condition, which in the opinion of the investigator, would put the subject
   at an unacceptable safety risk

   2. History of severe hypoglycemia (as defined in Section 11.3.3) in the past 6 months

   3. History of DKA (as defined in Section 11.3.4) in the past 6 months, unrelated to an
   intercurrent illness, infusion set failure or initial diagnosis

   4. Diagnosed with sickle cell disease

   5. Diagnosed with hemophilia or any other bleeding disorders

   6. Plans to receive blood transfusion over the course of the study

   7. Currently diagnosed with anorexia nervosa or bulimia

   8. Acute or chronic kidney disease (e.g. estimated GFR < 45) or currently on hemodialysis

   9. History of adrenal insufficiency

10. Has taken oral or injectable steroids within the past 8 weeks or plans to take oral or
   injectable steroids during the course of the study

11. Unable to tolerate adhesive tape or has any unresolved skin condition in the area of
   sensor or pump placement

12. Plans to use insulin other than U-100 insulin intended for use in the study device
   during the course of the study

13. Use of non-insulin anti-diabetic medication other than metformin (e.g. GLP1 agonist,
   SGLT2 inhibitor, DPP-4 inhibitor, pramlintide)

14. Current or known history of coronary artery disease that is not stable with medical
   management, including unstable angina, or angina that prevents moderate exercise
   despite medical management, or a history of myocardial infarction, percutaneous
   coronary intervention, or coronary artery bypass grafting within the previous 12
   months.

15. For subjects >50 years old or with diabetes duration >20 years, abnormal
   electrocardiogram consistent with increased risk of arrhythmia, ischemia, or prolonged
   QTc interval (> 450 ms)

16. Thyroid Stimulating Hormone (TSH) is outside of normal range with clinical signs of
   hypothyroidism or hyperthyroidism

17. Pregnant or lactating, or is a woman of childbearing potential and not on acceptable
   form of birth control (acceptable includes abstinence, condoms, oral/injectable
   contraceptives, IUD or implant)

18. Participation in another clinical study using an investigational drug or device within
   the preceding 30-days or intends to participate during the study period

19. Unable to follow clinical protocol for the duration of the study or is otherwise
   deemed unacceptable to participate in the study per the investigator's clinical
   judgment.