Continuous Glucose Monitoring-Informed Basal Insulin Optimization System in Adults with Type 2 Diabetes: Initial Evaluation of Efficacy, Safety, and Impact on Patient-Reported Outcomes.

INTRODUCTION: Clinical inertia and the complexity of basal insulin titration are major barriers to optimal glycemic control in adults with type 2 diabetes (T2D). A prototype of the Dexcom Smart Basal system known as basal therapy optimization (BTO), a continuous glucose monitoring (CGM)-informed basal insulin optimization system, was evaluated for its efficacy, safety, and impact on patient-reported outcomes (PRO). METHODS: In this prospective, single-arm study, 14 adults with T2D (three initiating and 11 optimizing basal insulin) used the BTO system. The study consisted of three phases: a ten-day baseline, up to 35 days of active titration, and a 20-day post-titration follow-up. Outcomes included change in CGM-derived glycemic metrics (mean glucose, time in range [TIR], time above range [TAR], time below range [TBR]), fasting blood glucose (FBG), and PROs (diabetes treatment satisfaction, glucose monitoring satisfaction, and patient-doctor depth of relationship) assessed using validated questionnaires. Safety was also assessed by the number of adverse events. RESULTS: All participants completed the study. The BTO system generated 401 insulin dose recommendations, with 96.5% accepted by the healthcare provider. After BTO-guided titration, mean glucose decreased by median (IQR) 26.3 (- 64.6, - 6.0) mg/dl (p = 0.0031), TIR 70-180 mg/dl increased by 16.0 (2.5, 43.7) percentage points (p = 0.0017), TAR > 180 mg/dl decreased by 15.9 (- 43.7, - 2.5) percentage points (p = 0.0017), and TBR < 70 mg/dl remained low (0.0-0.1%), with no clinically significant change in TBR. Median FBG decreased by 17.8 (- 54.4, 2.3) mg/dl (p = 0.052). No BTO- or study-related- adverse or severe adverse events were reported. Treatment satisfaction was significantly higher; median post-titration Diabetes Treatment Satisfaction Questionnaire (DTSQ) Change score was 17 (14, 18) on a scale ranging from - 18 to 18 and was significantly different from baseline DTSQ status score (p = 0.001). High satisfaction with glucose management and strong patient-provider relationships were preserved. Three illustrative cases highlighted successful insulin dose optimization through dose increases or decreases. CONCLUSIONS: CGM-informed basal insulin optimization with a prototype of Dexcom Smart Basal was associated with improvements in glycemic control and treatment satisfaction in adults with T2D, with a favorable safety profile. The system may help overcome clinical inertia and support individualized insulin titration in real-world settings. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT07681375 (Submitted for retrospective registration on 1/28/2026 and registered on 7/1/2026).