To assess the safety and performance of the Insulet AP (artificial pancreas) system, using the Omnipod® insulin management system, Dexcom G4 Share® AP System and personalized model predictive control algorithm in adults with type 1 diabetes consuming high fat meals and undertaking moderate intensity exercise.

The two-part study schedule consists of a 7±1 day outpatient, open-loop phase, followed by one 54-hour, hybrid closed-loop phases conducted in a supervised CRC or hotel/rental house setting.

Inclusion Criteria:

1. Age at time of consent 18.0 to 65.0 years
2. Diagnosed with type 1 diabetes for at least one year. Diagnosis is based on investigator's clinical judgment.
3. Total daily dose (TDD) of insulin ≥0.3 units/kg/day and A1C >6% at screening
4. Currently using an insulin pump with U-100 rapid-acting insulin analogs and on pump therapy for at least 6 months prior to study start
5. Willing to use the study CGM device for the duration of the study
6. Willing to use the Omnipod® Insulin Management System during the study
7. Willing to perform all fingerstick BG testing with the study-approved glucose meter at the frequency specified in the study protocol
8. Willing to abide by meal recommendations for breakfast, lunch and dinner during the study
9. Willing to participate in moderate intensity exercise for up to 45 minutes if taking part in Option B
10. Willing to refrain from use of acetaminophen and supplemental vitamin C (>2000 mg/daily) for the entire duration of participation in the study
11. Willing and able to sign the Informed Consent Form (ICF)

Exclusion Criteria:

1. A1C >10% at the screening visit
2. One or more episodes of severe hypoglycemia requiring emergency room (ER) visit or hospitalization within the past 6 months
3. Hypoglycemic unawareness as determined by a score of ≥4 "R" responses on the Clarke Questionnaire
4. One or more episodes of diabetic ketoacidosis requiring ER visit or hospitalization within the past 6 months
5. Used non-insulin anti-diabetic medication within last 30 days
6. 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)
7. Dermatological conditions at the proposed sensor wear sites that in the investigator's opinion could preclude ability to wear the Pod and/or the Dexcom sensor
8. Current or known history of cardiovascular disease, arrhythmia, myocardial infarction (MI) or stroke. An electrocardiogram (ECG) must be obtained within 6 months.
9. Currently undergoing systemic treatment with steroids or immunosuppressive medication
10. Current illness that would interfere with participation in the study
11. Currently participating in another clinical study using an investigational drug or device
12. Recent (within the preceding 30 days) participation in a clinical study using an investigational drug.