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Phase 3CompletedNCT03844789

Control-IQ closed-loop in children 6–13 (DCLP5 pediatric pivotal)

A 16-week, 4-site U.S. randomized trial (n=101) in children aged 6–13 testing the t:slim X2 with Control-IQ automated insulin delivery against a sensor-augmented pump. Time in range rose to 67% with closed-loop vs 55% with control (an 11-point adjusted gain, ~2.6 extra hours/day in range) with no increase in low glucose and no DKA or severe hypoglycemia. These results supported the FDA's June 2020 expansion of the Control-IQ age indication down to 6 years.

Primary endpoints

  • Percentage of time the glucose level was in the target range of 70–180 mg/dL (3.9–10.0 mmol/L), measured by continuous glucose monitoring over the 16-week treatment period

Results so far

Closed-loop beat the control therapy. Time in the 70–180 mg/dL target range rose from 53% at baseline to 67% over 16 weeks with closed-loop, versus 51% to 55% with the sensor-augmented pump — an adjusted difference of 11 percentage points (about 2.6 more hours per day in range; 95% CI 7 to 14; P<0.001). Mean glucose was about 13 mg/dL lower with closed-loop (P<0.001). Time spent low (below 70 mg/dL) stayed low and similar in both groups (median 1.6% vs 1.8%). The system ran in closed-loop mode a median 93% of the time. No diabetic ketoacidosis or severe hypoglycemia occurred in either group. The HbA1c difference (about 0.4 points) was not statistically significant.

The full picture

What this trial tested and why it matters

Automated insulin delivery (AID), sometimes called an "artificial pancreas," links a continuous glucose monitor (CGM) to an insulin pump through software that adjusts insulin automatically every few minutes. When this trial ran, the t:slim X2 pump with Control-IQ technology had just been cleared for people aged 14 and up, but not for younger children.1 This study — part of the International Diabetes Closed-Loop (iDCL) program, known as DCLP5 — asked whether the same system was safe and effective in school-aged children, whose smaller insulin needs, unpredictable eating, and activity make glucose harder to control.2

Who it was for

The trial enrolled 101 children aged 6 to 13 with type 1 diabetes for at least a year.2 Both well-controlled and less-well-controlled children took part — baseline HbA1c ranged from 5.7% to 10.1%.2

How it was designed

This was a 16-week, multicenter, randomized, open-label trial at four U.S. sites (Stanford, the Barbara Davis Center in Colorado, the University of Virginia, and Yale).23 Children were assigned in a 3:1 ratio: 78 to the Control-IQ closed-loop system (t:slim X2 pump plus Dexcom G6 CGM) and 23 to a control group using a sensor-augmented pump.2 The main question was simple: what fraction of the day is glucose kept in the healthy target range of 70–180 mg/dL?2 The University of Virginia led the study, funded by Tandem Diabetes Care and the NIDDK.23

The key results

Closed-loop clearly won. Time in the 70–180 mg/dL range climbed from 53% to 67% with Control-IQ but barely moved (51% to 55%) in the control group — an adjusted gain of 11 percentage points, roughly 2.6 extra hours per day in range (95% CI 7 to 14; P<0.001).2 Mean glucose fell about 13 mg/dL more with closed-loop.2 Crucially, this came without more low-glucose time: time below 70 mg/dL was low in both groups (median 1.6% vs 1.8%), and there were no episodes of diabetic ketoacidosis or severe hypoglycemia in either group.2 The system ran in closed-loop mode a median 93% of the time, showing children and families could rely on it day to day.2

What it means and what came next

These results directly supported the FDA's decision on June 17, 2020 to expand the Control-IQ age indication down to 6 years, having previously cleared it only for ages 14 and older.4 A smaller earlier feasibility study had already shown the same system improved time in range in 6-to-12-year-olds during short home use, paving the way for this larger pivotal trial.5 Together, this work helped make modern automated insulin delivery a standard option for school-aged children.

References

  1. Tandem Diabetes Care. FDA Clearance of the t:slim X2 Insulin Pump with Control-IQ Technology. Tandem Diabetes Care newsroom (2019). https://investor.tandemdiabetes.com/news-releases/news-release-details/tandem-diabetes-care-announces-fda-clearance-tslim-x2-insulin ↩

  2. Breton MD, Kanapka LG, Beck RW, et al. A Randomized Trial of Closed-Loop Control in Children with Type 1 Diabetes. New England Journal of Medicine (2020); 383(9):836–845. https://doi.org/10.1056/NEJMoa2004736 ↩ ↩2 ↩3 ↩4 ↩5 ↩6 ↩7 ↩8 ↩9 ↩10 ↩11

  3. U.S. National Library of Medicine. The International Diabetes Closed Loop (iDCL) Trial: Clinical Acceptance of the Artificial Pancreas in Pediatrics (NCT03844789). ClinicalTrials.gov (2020). https://clinicaltrials.gov/study/NCT03844789 ↩ ↩2

  4. Breakthrough T1D (JDRF). Tandem Control-IQ — Now Authorized for Children. Breakthrough T1D news (2020). https://www.breakthrought1d.org/news-and-updates/tandem-control-iq-now-authorized-for-children/ ↩

  5. Forlenza GP, Ekhlaspour L, Breton M, et al. Successful At-Home Use of the Tandem Control-IQ Artificial Pancreas System in Young Children During a Randomized Controlled Trial. Diabetes Technology & Therapeutics (2019); 21(4):159–169. https://doi.org/10.1089/dia.2019.0011 ↩