The purpose of this trial is to test and refine the PACTAID smart phone application in adults with type 1 diabetes mellitus to help manage exercise while on automated insulin delivery systems with the goal of improving glycemic control during and after exercise as well as improving multiple other cardiovascular risk factors.

This trial will be conducted in two phases. In Phase 1, we will test the PACTAID app in adults with type 1 diabetes mellitus to help manage exercise while on an automated insulin delivery system for four weeks. In phase 2, we will use a refined version of the PACTAID app in those same adults from phase 1 for four weeks. A 2-4-week period will be between phase 1 and phase 2 in which the app will be refined. There is one clinical site, Mayo Clinic, and two sites creating the app, Arizona State University and University of Houston. The study will enroll up to 8 subjects at Mayo Clinic.

Inclusion Criteria:

• Male or Female between age of 18-65 yrs.
• T1D diagnosis will be confirmed by C- Peptide (≤0.6 ng/ml) with a simultaneous fasting glucose concentration 80-225 mg/dL.
• T1D using AID either tandem Control IQ, Medtronic 780G, Omnipod 5 or Ilet bionic pancreas for diabetes management at the time of screening for at least 3-month duration.
• CGM and insulin pump data available for > 70% for last 2 weeks.
• T1D without atherosclerotic cardiovascular disease
• HbA1c ≤10 %
• Able to understand English language.
• Currently using an insulin-to-carbohydrate ratio to calculate meal bolus sizes.
• Willing to complete study procedures.
• Willing to wear study devices.
• An understanding of and willingness to follow the protocol, perform all 3 types of exercises as per protocol, and sign the informed consent.
• Non-smoker
• Satisfactory EKG in last one year or if not available, satisfactory baseline EKG at screening

Exclusion Criteria:

• Anti-hyperglycemic drugs other than insulin including metformin.

• Pregnancy or contemplating pregnancy in study

• Untreated hyperthyroidism or hypothyroidism, abnormal (out of Reference range) TSH at the time of screening

• Severe hypoglycemia or DKA in last 3 months.

• Baseline exercise status-those already doing vigorous exercise such as 1 hour per day will be excluded.

• BMI ≥35 kg/m2

• Obstructive sleep apnea not controlled on CPAP.

• Chronic obstructive pulmonary disease

• Asthma limiting exercise.

• Uncontrolled hypertension, Blood pressure ≥ 140/90 mmHg with ≥ 2 antihypertensive medications

• Clinically diagnosed obstructive coronary artery disease or any other significant cardiac condition or heart failure

• Uncontrolled or recurrent ventricular tachycardia

• Any medication affecting heart rate.

• Clinical diagnosis of unstable proliferative diabetic retinopathy

• Previous Organ Transplant with or without current graft function

• Currently receiving chemotherapy or long-term immunosuppressant (glucocorticoids etc.) therapy

• COVID positive at the time of screening

• Clinically diagnosed autonomic neuropathy

• Abnormal liver function test results (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.

• Abnormal renal function test results (calculated GFR <60 mL/min/1.73m2)

• Active gastroparesis

• Abuse of alcohol or recreational drugs

• Infectious process not anticipated to resolve prior to study procedures (e.g., meningitis, pneumonia, osteomyelitis).

• If on anti-depressant, lack of stability on the medication for the past 2 months prior to enrollment in the study

• Any known medical condition that in the judgment of the investigator might interfere with the completion of the protocol such as the following examples:

  1. Inpatient psychiatric treatment in the past 6 months
  2. Presence of a known adrenal disorder
  3. 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
  4. Participating in any other treatment study

Note: Other protocol defined Inclusion/Exclusion Criteria may apply.

Eligibility last updated 08/15/2024. Questions regarding updates should be directed to the study team contact.