Tandem Freedom Feasibility Study 1

This feasibility study is a prospective, single arm study evaluating the Tandem Freedom system in adults with type 1 diabetes. Existing Control-IQ technology users will use Control-IQ technology at home for a 1 week run-in, then will use Tandem Freedom in a supervised hotel setting.

Study Overview

• Status: Completed
• Conditions: Diabetes Mellitus, Type 1
• Intervention / Treatment: Device: t:slim X2 insulin pump with Tandem Freedom Algorithm

Detailed Description

After a 1 week Control-IQ run-in at home, 10 adults who are existing Control-IQ users with type 1 diabetes will use the Tandem Freedom System for 1 day with boluses, and 1 day without boluses, in a supervised hotel setting. Participants will perform meal and exercise challenges. The primary outcome is safety events. CGM time in ranges will also be evaluated.

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• New Zealand
  • Christchurch, New Zealand, 8140
    • University of Otago

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age ≥18 years old
• Diagnosis of type 1 diabetes for at least 1 year
• Current Control-IQ user, having been prescribed Control-IQ for at least 3 months
• HbA1c ≤10%, recorded in the last 3 months
• Investigator has confidence that the participant can successfully operate all study devices and is capable of adhering to the protocol, including performing the weekend hotel observed setting portion of the study.
• Willing to use only aspart (novorapid) or lispro (humalog) insulin with the study pump, with no use of long-acting basal insulin injections, or inhaled insulin with the study pump.
• Have current glucagon product to treat severe hypoglycemia (injectable or nasal) at home (site will provide prescription if they do not have one)

Exclusion Criteria:

• More than 1 episode of diabetic ketoacidosis (DKA) in the past 6 months
• More than 1 episode of severe hypoglycemia (needing assistance) in the past 6 months
• Inpatient psychiatric treatment in the past 6 months

• For Female: Currently pregnant or planning to become pregnant during the time period of study participation

  1. A negative pregnancy test will be required for all females of child-bearing potential
  2. Counseling on appropriate birth control options will be provided to all females of child-bearing potential
• 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).
• Hemophilia or any other bleeding disorder
• Hemoglobinopathy
• History of heart, liver, lung or kidney disease determined by investigator to interfere with the study
• History of allergic reaction to Humalog or Novorapid
• Use of any medications determined by investigator to interfere with study
• Significant chronic kidney disease (which could impact CGM accuracy in investigator's judgment) or hemodialysis
• Concurrent use of any medication that could interfere with the study CGM, such as hydroxyurea
• History of adrenal insufficiency
• History of abnormal TSH consistent with hypothyroidism or hyperthyroidism that is not appropriately treated
• History of gastroparesis
• A condition, which in the opinion of the investigator or designee, would put the participant or study at risk
• Participation in another pharmaceutical or device trial at the time of enrollment or anticipated for during the time period of study participation
• Employed by, or having immediate family members employed by Tandem Diabetes Care, Inc., or having a direct supervisor at place of employment who is also directly involved in conducting the clinical trial (as a study investigator, coordinator, etc.); or having a first-degree relative who is directly involved in conducting the clinical trial

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Tandem Freedom; After a one week run-in period with Control-IQ technology, participants used the Tandem Freedom system for one day with insulin boluses and one day without insulin boluses. Participants performed meal and exercise challenges in a supervised hotel setting.	Device: t:slim X2 insulin pump with Tandem Freedom Algorithm; Participants will use the Tandem Freedom system for one day with insulin boluses and one day without insulin boluses.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Severe Hypoglycemia Events	Number of severe hypoglycemia events (with cognitive impairment such that assistance of another individual is needed for treatment)	Control-IQ Run-in with boluses 7 days, day 8 freedom with meal bolus and day 9 freedom without meal bolus
Diabetic Ketoacidosis Events	Number of diabetic ketoacidosis events	Control-IQ Run-in with boluses 7 days, day 8 freedom with meal bolus and day 9 freedom without meal bolus

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent Time <54 mg/dL	CGM measured percent time <54 mg/dL	Control-IQ Run-in with boluses 7 days, day 8 freedom with meal bolus and day 9 freedom without meal bolus
Percent Time <70 mg/dL	CGM measured percent time <70 mg/dL	Control-IQ Run-in with boluses 7 days, day 8 freedom with meal bolus and day 9 freedom without meal bolus
Percent Time in Range 70 - 180 mg/dL	CGM measured percent time in range 70 - 180 mg/dL	Control-IQ Run-in with boluses 7 days, day 8 freedom with meal bolus and day 9 freedom without meal bolus
Percent Time in Range 70 - 140 mg/dL	CGM measured percent time in range 70 - 140 mg/dL	Control-IQ Run-in with boluses 7 days, day 8 freedom with meal bolus and day 9 freedom without meal bolus
Percent Time >180 mg/dL	CGM measured percent time >180 mg/dL	Control-IQ Run-in with boluses 7 days, day 8 freedom with meal bolus and day 9 freedom without meal bolus
Percent Time >250 mg/dL	CGM measured percent time >250mg/dL	Control-IQ Run-in with boluses 7 days, day 8 freedom with meal bolus and day 9 freedom without meal bolus
Mean Glucose (mg/dL)	CGM measured mean glucose (mg/dL)	Control-IQ Run-in with boluses 7 days, day 8 freedom with meal bolus and day 9 freedom without meal bolus
Glucose Coefficient of Variation (%)	CGM measured Coefficient of Variation (%)	Control-IQ Run-in with boluses 7 days, day 8 freedom with meal bolus and day 9 freedom without meal bolus
Glucose Standard Deviation (mg/dL)	CGM measured Standard Deviation (mg/dL)	Control-IQ Run-in with boluses 7 days, day 8 freedom with meal bolus and day 9 freedom without meal bolus

Collaborators and Investigators

• Sponsor: Tandem Diabetes Care, Inc.
• Investigators: Study Director: Jordan Pinsker, MD, Tandem Diabetes Care

Study record dates

Study Major Dates

• Study Start (Actual): May 29, 2024
• Primary Completion (Actual): June 10, 2024
• Study Completion (Actual): June 10, 2024

Study Registration Dates

• First Submitted: May 20, 2024
• First Submitted That Met QC Criteria: May 20, 2024
• First Posted (Actual): May 24, 2024

Study Record Updates

• Last Update Posted (Actual): November 18, 2025
• Last Update Submitted That Met QC Criteria: November 3, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: T1D; type 1 diabetes; automated insulin delivery; Tandem; t:slim X2
• Additional Relevant MeSH Terms: Endocrine System Diseases; Metabolic Diseases; Autoimmune Diseases; Immune System Diseases; Glucose Metabolism Disorders; Diabetes Mellitus; Nutritional and Metabolic Diseases; Diabetes Mellitus, Type 1; Hypoglycemic Agents; Physiological Effects of Drugs; Insulin
• Other Study ID Numbers: TP-0017517; U1111-1307-6267 (Other Identifier: ICTRP)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes