The Food and Drug Administration recently cleared the t:slim X2 with Control-IQ technology in the United States. This advanced hybrid closed-loop system automatically adjusts insulin based on predicted sensor glucose (SG) levels to help increase sensor time in range (TIR) (70-180 mg/dL). The pivotal DCLP3 trial demonstrated noteworthy glycemic improvements in people with type 1 diabetes (PwT1D) using Control-IQ technology. However, DCLP3 did not include people with type 2 diabetes (PwT2D). We performed retrospective analysis of users who uploaded at least 14 days of pre and 14 days of post Control-IQ software usage data to Tandem’s t:connect® web application as of March 11, 2020 and had ≥75% CGM use during this time. Glycemic outcomes, total daily insulin (TDI), and time in closed loop were analyzed by diabetes type. Of the 3,278 PwDs included in the sample, 144 had T2D, 52% were female, mean age=43 years (SD=17.47), diabetes duration=23 years (SD=15). Wilcoxon signed-rank tests were used to examine pre-post differences in outcomes by diabetes type. Post 14-day Control-IQ technology use, PwT1Ds recorded 96% time in closed loop and showed significant improvements in their TIR (+9% from pre, p<0.001), reduced time in SG<70 (-0.04% from pre, p<0.001), and SG>180 (-8.45% from pre, p<0.001). Median TDI at post was 48 units (pre=46 units, p<0.001). Similar trends were observed for the type 2 sample, in that PwT2Ds recorded 96% time in closed loop and showed significant improvements in TIR (+6% from pre, p<0.001) and reduced SG time >180 (-5.8% from pre, p<0.001). Median SG time <70 remained unchanged (0.2%). Median total daily insulin for PwT2Ds increased to 82 units from pre-CIQ use of 73 units (p=0.003). These results from early adopters of Control-IQ technology confirm its efficacy in assisting both PwT1Ds and PwT2Ds achieve their recommended glycemic targets and improve their glycemic control.


S. Habif: Employee; Self; Tandem Diabetes Care. A. Constantin: Employee; Self; Tandem Diabetes Care. Other Relationship; Self; Bigfoot Biomedical. L. Mueller: Research Support; Self; Dexcom, Inc., Tandem Diabetes Care. H. Singh: Employee; Self; Tandem Diabetes Care.

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