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).