Feasibility Study of Extended Wear Insulin Infusion Set Options During Home Use in People With Type 1 Diabetes

All participants will use the SteadiSet insulin infusion set for 6 wear periods of up to 7 days each.

The 2 treatment arms are:

Existing t:slim X2 Users:

• t:slim X2 insulin pump with SteadiSet (43 inches) and an enhanced filling process (3 wear periods)
• t:slim X2 insulin pump with SteadiSet (43 inches) with no side ports (3 wear periods)

Existing Mobi Users:

• Mobi Insulin Pump with SteadiSet (5 inches) and an enhanced filling process (3 wear periods)
• Mobi Insulin Pump and SteadiSet (5 inches) (3 wear periods)

Inclusion criteria

• Age 18 to 80 years old inclusive
• Generally in good health, as determined by the investigator
• Living in the United States with no plans to move outside the United States during the study
• Diagnosis of T1D for at least 12 months
• Currently using a Tandem pump
• Current Dexcom CGM user
• HbA1c <9.0% in the last 6 months.
• Willing to implement and adhere to pump alert/alarm settings on a study-provided pump as instructed during the study
• Willing to wear each investigational infusion set for up to 7 days during each of the wear periods in the study
• Willing to perform blood ketone and blood glucose (fingerstick) measurements as directed using provided ketone and blood glucose meters and strips
• If using Tandem Mobi, has a compatible cellular phone that can run the Tandem Mobi Mobile App
• BMI in the range 18-35 kg/m2, both inclusive
• Currently using one of the following insulins with no expectation of a need to change insulin type during the study:

• Humalog™ (or generic insulin lispro)
• NovoLog™ (or generic insulin aspart)
• Willing to change insulin cartridge every 48-72 hours, as recommended by patient's healthcare provider during the study
• Has the ability to understand and comply with protocol procedures and to provide informed consent

Exclusion criteria

• Concurrent use of any non-insulin glucose-lowering agent, other than metformin (for example, GLP-1 agonists, Symlin, DPP-4 inhibitors, SGLT-2 inhibitors, sulfonylureas)
• Female subject is pregnant, planning to become pregnant, or not using adequate method of contraception
• Episodes of severe hypoglycemia in the last 6 months resulting in:

• Medical Assistance (i.e., paramedics, hospital evaluation or hospitalization)
• Loss of consciousness
• Seizures
• One or more episodes of diabetic ketoacidosis (DKA) in the last 6 months requiring hospitalization
• Currently on a ketogenic or low-carbohydrate diet of less than 60 grams of carbohydrates per day, or intending to begin one during the study period
• Known history of any of the following conditions:

• Cushing's Disease
• Adrenal insufficiency
• Pancreatic islet cell tumor
• Insulinoma
• Lipodystrophy
• Extensive lipohypertrophy, as assessed by the investigator
• Undergoing treatment with systemic oral or intravenous corticosteroids, at or within the last 8 weeks from screening. Inhaled glucocorticoids are allowed.
• Significant history of any of the following, that in the opinion of the investigator would compromise safety or successful study participation:

• Alcoholism
• Drug abuse
• Significant acute or chronic illness, that in the opinion of the investigator might interfere with safety or integrity of study results
• Current participation in another clinical drug or device study
• Immediate family member (spouse, biological or legal guardian, child, sibling, parent) who is a study site personnel directly affiliated with this study or who is an employee of Tandem Diabetes Care