The Monitoring Study

To conduct an outpatient study testing two configurations of the bionic pancreas (bi-hormonal and insulin-only) with and without remote monitoring of hypoglycemia in 25 adult (≥ 18 years of age) subjects with type 1 diabetes in a random-order crossover study versus usual care with an insulin pump with and without remote monitoring of hypoglycemia.

The rationale for this study is to measure the safety of eliminating the glycemic monitoring that the investigators have done in all of the previous outpatient studies under both insulin only and bihormonal bionic pancreas control. The investigators are planning to transition the outpatient studies to an integrated bionic pancreas, the iLet, in the near future. The intended use of this device does not include remote monitoring, which would not be feasible on a commercial scale. Therefore, in this trial the investigators will test the effects on hypoglycemia of eliminating blood glucose related monitoring. In addition, the investigators will perform a pilot trial testing the effects of the bionic pancreas on food intake, exercise, weight and body composition. The primary purpose of this pilot is to assess the feasibility of performing these measurements in the context of a larger trial and to collect data that can be used to power sub-studies of pivotal trials looking at these outcomes. Finally, the investigators will test the accuracy of two new CGM devices to see if they have sufficient accuracy to provide glucose data to the bionic pancreas. If so, this would provide new options for users who may have difficulties with the only currently validated CGM for this purpose, the Dexcom G4 AP / G5 platform.

Eligibility Criteria:
Inclusion Criteria:

* Age ≥ 18 years and have had clinical type 1 diabetes for at least one year managed using an insulin pump for ≥ 6 months
* Prescription medication regimen stable for \> 1 month (except for medications that will not affect the safety of the study and are not expected to affect any outcome of the study, in the judgment of the principal investigator)
* Live within a 60 minute drive-time radius of the central monitoring location
* Willing to remain within a 120 minute drive-time radius of the central monitoring location throughout the study
* Have someone over 18 years of age who lives with them, has access to where they sleep, is willing to be in the house when the subject is sleeping, and is willing to receive calls from the study staff and check the welfare of the study subject if telemetry shows a technical problem or severe biochemical hypoglycemia without subject response and the subject does not answer their telephone (up to two individuals can share this role, but they must be willing to carefully coordinate with each other and the subject so that one of them is clearly designated as having this responsibility at any given time)
* Willing to wear one or two infusion sets and one Dexcom CGM sensor and change sets frequently (at least one new glucagon infusion set daily during bi-hormonal arms, and insulin infusion set every other day throughout the study)
* Willing to wear two additional CGM sensors that must be placed in the upper arm

Exclusion Criteria:

* Unable to provide informed consent (e.g. impaired cognition or judgment)
* Unable to safely comply with study procedures and reporting requirements (e.g. impairment of vision or dexterity that prevents safe operation of the bionic pancreas, impaired memory, unable to speak and read English)
* Current participation in another diabetes-related clinical trial that, in the judgment of the principal investigator, will compromise the results of this study or the safety of the subject
* Pregnancy (positive urine HCG), breast feeding, plan to become pregnant in the immediate future, or sexually active without use of contraception Subjects must use acceptable contraception for the two weeks prior to the study, throughout the study and for the two weeks following the study.

Acceptable contraception methods include: Oral contraceptive pill (OCP), Intrauterine Device (IUD, hormonal or copper), Male condoms, Female condoms, Diaphragm or cervical cap with spermicide, Contraceptive patch (such as OrthoEvra), Contraceptive implant (such as Implanon, Nexplanon), Vaginal ring (such as NuvaRing), Progestin shot (such as Depo-Provera), Male partner with a vasectomy proven to be effective by semen analysis

* Need to go outside of the designated geographic boundaries during the study
* Current alcohol abuse (intake averaging \> 3 drinks daily in last 30 days), use of marijuana within 1 month of enrollment, or other substance abuse (use within the last 6 months of controlled substances other than marijuana without a prescription)
* Unwilling or unable to refrain from drinking more than 2 drinks in an hour or more than 4 drinks in a day or use of marijuana during the trial
* Unwilling or unable or to avoid use of drugs that may dull the sensorium, reduce sensitivity to symptoms of hypoglycemia, or hinder decision making during the period of participation in the study (use of beta blockers will be allowed as long as the dose is stable and the subject does not meet the criteria for hypoglycemia unawareness while taking that stable dose, but use of benzodiazepines or narcotics, even if by prescription, may be excluded according to the judgment of the principal investigator)
* History of liver disease that is expected to interfere with the anti-hypoglycemia action of glucagon (e.g. liver failure or cirrhosis). Other liver disease (i.e. active hepatitis, steatosis, active biliary disease, any tumor of the liver, hemochromatosis, glycogen storage disease) may exclude the subject if it causes significant compromise to liver function or may do so in an unpredictable fashion.
* Renal failure on dialysis
* Personal history of cystic fibrosis, pancreatitis, pancreatic tumor, or any other pancreatic disease
* Any known history of coronary artery disease including, but not limited to, history of myocardial infarction, stress test showing ischemia, history of angina, or history of intervention such as coronary artery bypass grafting, percutaneous coronary intervention, or enzymatic lysis of a presumed coronary occlusion)
* Abnormal EKG consistent with coronary artery disease or increased risk of malignant arrhythmia including, but not limited to, evidence of active ischemia, prior myocardial infarction, proximal LAD critical stenosis (Wellen's sign), prolonged QT interval (\> 440 ms). Non-specific ST segment and T wave changes are not grounds for exclusion in the absence of symptoms or history of heart disease. A reassuring evaluation by a cardiologist after an abnormal EKG finding may allow participation.
* Congestive heart failure (established history of CHF, lower extremity edema, paroxysmal nocturnal dyspnea, or orthopnea)
* History of TIA or stroke
* Seizure disorder, history of any non-hypoglycemic seizure within the last two years, or ongoing treatment with anticonvulsants
* History of hypoglycemic seizures (grand-mal) or coma in the last year
* History of pheochromocytoma: fractionated metanephrines will be tested in patients with history increasing the risk for a catecholamine secreting tumor:

  * Episodic or treatment refractory (requiring 4 or more medications to achieve normotension) hypertension
  * Paroxysms of tachycardia, pallor, or headache
  * Personal or family history of MEN 2A, MEN 2B, neurofibromatosis, or von Hippel-Lindau disease
* History of adrenal disease or tumor
* Hypertension with systolic BP ≥160 mm Hg or diastolic BP ≥100 despite treatment
* Untreated or inadequately treated mental illness (indicators would include symptoms such as psychosis, hallucinations, mania, and any psychiatric hospitalization in the last year), or treatment with anti-psychotic medications that are known to affect glucose regulation.
* Electrically powered implants (e.g. cochlear implants, neurostimulators) that might be susceptible to RF interference
* The presence of any other active implanted device
* Unable to completely avoid acetaminophen for duration of study
* Unable to completely avoid ascorbic acid (Vitamin C) for duration of study
* Unable to completely avoid salicylic acid (used in some pain relievers such as Aspirin and some skin care products)
* History of adverse reaction to glucagon (including allergy) besides nausea and vomiting
* Established history of allergy or severe reaction to adhesive or tape that must be used in the study
* History of eating disorder within the last 2 years, such as anorexia, bulimia, or diabulemia or omission of insulin to manipulate weight
* History of intentional, inappropriate administration of insulin leading to severe hypoglycemia requiring treatment
* Use of oral (e.g. thiazolidinediones, biguanides, sulfonylureas, glitinides, DPP-4 inhibitors, SGLT-2 inhibitors) anti-diabetic medications
* Lives in or frequents areas with poor Verizon wireless network coverage (which would prevent remote monitoring)
* Any factors that, in the opinion of the principal investigator would interfere with the safe completion of the study
* A condition preventing or complicating the placement, operation or removal of the Senseonics sensor or wearing of transmitter, including upper extremity deformities or skin condition
* Currently receiving (or likely to need during the study period): immunosuppressant therapy, chemotherapy, anticoagulant/antithrombotic therapy (excluding aspirin), glucocorticoids (excluding ophthalmic or nasal). This does include the use of inhaled and topical glucocorticoids and antibiotics for chronic infection
* A condition requiring or likely requiring magnetic resonance imaging (MRI), Computed Tomography (CT) scan, or high-frequency electrical heat (diathermy)
* A known topical or local anesthetic allergy
* A known glucocorticoids allergy
* The presence of any other CGM sensor or transmitter located in the upper arm (other location is acceptable)
* Hemoglobin \< 12 g/dl