Background: The t:slim X2 with Control-IQ technology (“Control-IQ”) is an advanced hybrid closed-looped system. This analysis evaluated glycemic outcomes in Control-IQ users by payer type using Healthcare Effectiveness Data and Information Set (HEDIS) quality thresholds. HEDIS is used by >90% of health plans to measure performance and includes a metric to identify A1c control (<8.0%) and poor control (>9.0%). Glucose management indicator (GMI) is a recognized surrogate for A1c when sufficient data are provided (≥14 days, 70% CGM use). Methods: We retrospectively analyzed glycemic data for individuals with type 1 diabetes from 1/1/20 to 3/4/23 who used Control-IQ for ≥1 year (with ≥70% of CGM use in final 3 months) and had a recorded baseline A1c prior to Control-IQ initiation. Results were stratified by payer type, prior therapy, and baseline A1c. GMI was calculated for last 3 months and compared to baseline A1c. Results: Analysis included 20,319 users, with 42% (n= 8,493) on multiple daily injections (MDI) and 58% (n=11,826) on pump therapy at baseline. Control-IQ use significantly improved glycemic outcomes and mean HEDIS thresholds were achieved for all payer types and strata (table). Conclusion: Control-IQ use improved HEDIS A1c (GMI) outcomes across all payer types, with the largest glycemic improvement seen in those with the highest A1c at baseline and for prior MDI users. Disclosure B. V. Patel: Employee; Tandem Diabetes Care, Inc. Stock/Shareholder; Tandem Diabetes Care, Inc. G. Alencar: Employee; Tandem Diabetes Care, Inc. S. M. Wang: Employee; Tandem Diabetes Care, Inc. Stock/Shareholder; Tandem Diabetes Care, Inc. S. Leas: Employee; Tandem Diabetes Care, Inc. L. H. Messer: Employee; Tandem Diabetes Care, Inc. Consultant; Dexcom, Inc. Advisory Panel; Lilly. Consultant; Capillary Biomedical, Inc. Research Support; Beta Bionics, Inc., Medtronic, Insulet Corporation. J. E. Pinsker: Employee; Tandem Diabetes Care, Inc.

The Control-IQ Observational (CLIO) Study is an ongoing prospective, real-world evaluation of the Tandem Diabetes Care t:slim X2 insulin pump with Control-IQ technology in people with T1D. We assessed baseline HbA1c and Glucose Management Indicator (GMI) derived from sensor data from adult participants who completed the 12-month CLIO study. Adults ages ≥18 years who had ≥75% overall CGM use during this time were included in the analysis. Outcomes were analyzed using a Wilcoxon test. In all, 1,1participants (882 prior pump and 225 prior MDI users) , median age 41 years (IQR 30-54) , 57.2% female met the inclusion criteria. Median GMI was significantly lower at 12 months (7.0% [6.7-7.4]) vs. baseline HbA1c (7.2% [6.7-8.1]) (p<0.0001) . Participants ages 18-30 and 46-64 showed the greatest improvement from baseline (0.3% reduction) (p<0.0001) , while older adults (≥65-years) showed the lowest GMI at study end (6.9% [6.6-7.2]) . Prior MDI users reported higher HbA1c at baseline (7.7% [IQR=6.8-9.0]) vs. prior pumpers (7.2% [6.7-8.0]) . However, GMI at 12 months reflected glycemic improvements across all prior therapy modalities (prior MDI=7.0% [6.7-7.3]; prior pump=7.1% [6.7-7.4]) (p<0.0001) . This real-world evidence demonstrates significant glycemic improvements with Control-IQ technology in adults, regardless of prior therapy modality, that are sustained long-term across diverse groups of users. Disclosure R.Graham: Research Support; Tandem Diabetes Care, Inc. S.Habif: Employee; Tandem Diabetes Care, Inc. J.E.Pinsker: Employee; Tandem Diabetes Care, Inc., Stock/Shareholder; Tandem Diabetes Care, Inc. H.Singh: Employee; Tandem Diabetes Care, Inc. G.Alencar: Employee; Tandem Diabetes Care, Inc. L.Mueller: Employee; Tandem Diabetes Care, Inc., Research Support; Dexcom, Inc., Stock/Shareholder; Tandem Diabetes Care, Inc. M.L.Manning: Employee; Tandem Diabetes Care, Inc. K.N.White: Employee; Tandem Diabetes Care, Inc. A.Wheatcroft: Employee; Tandem Diabetes Care, Inc. K.Carmelo: None. E.S.Aronoffspencer: Research Support; Tandem Diabetes Care, Inc. Funding Tandem Diabetes Care

There is mounting evidence supporting the benefits of hybrid closed loop systems for type 1 diabetes (T1D) management. However, published studies lack long-term evaluation of these technologies in ethnically diverse patients including patient-reported outcomes (PROs) assessing lived experiences with these devices. As part of the Control-IQ Observational (CLIO) study, we evaluated psychosocial outcomes in T1D adults using the Tandem Diabetes Care t:slim X2 insulin pump with Control-IQ technology. Participants completed PRO measures including open-ended items at baseline (pre) , 3, 6, and 12 months (post) . Wilcox signed rank-test was used to assess differences and qualitative data was analyzed using thematic analysis. In all, 13adult study completers (57.6% female) (White=1084, Hispanic=86, Black=38, Asian=16, Mixed=42) were included in the analysis. Overall, there was a 25.2% improvement in satisfaction with insulin delivery device (IDD) using Control-IQ technology at post (mean=8.83±1.15) vs. pre (i.e., previous IDD) (7.06±2.04) (p<0.001) . The Asian cohort reported greater improvement (33.2%) than others. A significant reduction in diabetes impact (33.6%) was noted overall at post (p<0.001) with Hispanic participants reporting greater reduction in diabetes burden (42.8%) than others. For perceived impact of diabetes on quality of life, there was an overall reduction in diabetes impact at post (p<0.001) with Asians showing greater reduction (26.3%) vs. others, specifically in the “freedom to eat as you wish” aspect of life. At post, 71% reported improved sleep quality using Control-IQ technology. Thematic analysis supported these findings highlighting improved diabetes control, quality of life, and ease of use as valuable experiences supporting long-term use of Control-IQ technology. These data demonstrate substantial and sustained psychosocial improvements using Control-IQ technology in diverse ethnic cohorts with T1D. Disclosure H.Singh: Employee; Tandem Diabetes Care, Inc. E.S.Aronoffspencer: Research Support; Tandem Diabetes Care, Inc. J.E.Pinsker: Employee; Tandem Diabetes Care, Inc., Stock/Shareholder; Tandem Diabetes Care, Inc. S.Habif: Employee; Tandem Diabetes Care, Inc. G.Alencar: Employee; Tandem Diabetes Care, Inc. H.Sanchez: Employee; Tandem Diabetes Care, Inc. M.L.Manning: Employee; Tandem Diabetes Care, Inc. K.N.White: Employee; Tandem Diabetes Care, Inc. A.Wheatcroft: Employee; Tandem Diabetes Care, Inc. K.Carmelo: None. R.Graham: Research Support; Tandem Diabetes Care, Inc. L.Mueller: Employee; Tandem Diabetes Care, Inc., Research Support; Dexcom, Inc., Stock/Shareholder; Tandem Diabetes Care, Inc. Funding Tandem Diabetes Care

Despite increasing prevalence of T1D in ethnic minorities, they remain underrepresented in research studies evaluating diabetes technologies. Experiences of diverse cohorts are essential to assessing acceptability of diabetes devices. The Control-IQ Observational (CLIO) Study is an ongoing prospective, real-world evaluation of the Tandem Diabetes Care t:slim X2 insulin pump with Control-IQ technology in diverse people with T1D. We evaluated glycemic metrics from adults completing the 12-month CLIO study. Participants with ≥75% overall CGM use during this time were included in the analysis. Outcomes were analyzed using a Wilcoxon test. Sample included 1,045 adults (921 Whites, 74 Hispanics, 34 Blacks, 16 Asians) with Black participants reporting the highest baseline HbA1c (median=8% [IQR=7-8.6)) . Glucose Management Indicator (GMI) at study end reflected glycemic improvements for participants with Blacks showing a clinically relevant 0.7% overall reduction (7.3% [6.9-7.6]) (p<0.001) (Figure 1) . Overall, sensor time in range (TIR) at 12 months ranged from 64.9% [56.8-70.5] for Black participants to 72.6% [62.8-80.8] for the White cohort. These findings confirm long-term successful use of Control-IQ technology across diverse ethnicities. Further evaluation of glycemic disparities is recommended to help inform patient support systems. Disclosure R.Graham: Research Support; Tandem Diabetes Care, Inc. E.S.Aronoffspencer: Research Support; Tandem Diabetes Care, Inc. J.E.Pinsker: Employee; Tandem Diabetes Care, Inc., Stock/Shareholder; Tandem Diabetes Care, Inc. S.Habif: Employee; Tandem Diabetes Care, Inc. H.Singh: Employee; Tandem Diabetes Care, Inc. L.Mueller: Employee; Tandem Diabetes Care, Inc., Research Support; Dexcom, Inc., Stock/Shareholder; Tandem Diabetes Care, Inc. M.L.Manning: Employee; Tandem Diabetes Care, Inc. G.Alencar: Employee; Tandem Diabetes Care, Inc. K.N.White: Employee; Tandem Diabetes Care, Inc. A.Wheatcroft: Employee; Tandem Diabetes Care, Inc. K.Carmelo: None. R.Katchalski: Employee; Tandem Diabetes Care, Inc. Funding Tandem Diabetes Care