The t:slim X2 insulin pump with Control-IQ technology from Tandem Diabetes Care, Inc. was cleared by the Food and Drug Administration in December 2019. This study examined the commercial introduction of Control-IQ technology in the U.S. We performed a retrospective analysis of users who uploaded at least 30 days of pre and 30 days of post Control-IQ software update usage data to Tandem’s t:connect® web application as of March 11, 2020 and had ≥75% CGM use during this time (n=1,659). Outcomes included total daily insulin and sensor glucose values during open and closed-loop use of Control-IQ technology. Changes in glycemic outcomes were analyzed using the Wilcoxon signed-rank test. The mean age of patients was 43 years, 52% female, and mean diabetes duration was 21 years. Ninety percent of patients reported type 1 diabetes, 4% type 2 diabetes, and 6% “other” or unknown. The Control-IQ software update led to a 10% increase (p<0.001) of median sensor time in range (70-180 mg/dL) to 78% (IQR =69%-85%) due to a 10% decrease in sensor time >180mg/dL to 21% (IQR= 13%-30%) and a 0.1% decrease of sensor time <70mg/dL to 1.1.% (IQR=0.5%-2.2%). Improvements in sensor time in range were consistent across age groups. Mean sensor glucose fell from 161 mg/dL to 148 mg/dL while the median total daily insulin increased from 48u to 49u. Median time in closed-loop was 96% (IQR = 93%-98%). These real-world data demonstrate improved sensor time in range without increasing hypoglycemia.


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

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