Introduction and Objective: The efficacy of glucagon-like peptide 1 receptor agonists (GLP-1RA) as monotherapy in newly diagnosed youth with type 2 diabetes (YT2D) is unknown. We hypothesize that GLP-1RA are superior to metformin in HbA1c and BMI reduction in YT2D. Methods: This retrospective review extracted data from YT2D from one urban pediatric hospital. Inclusion criteria included age <21, prescription of GLP1-RA or metformin at diagnosis between September 2019 and December 2023. Study observation (up to one year) excluded visits that included concurrent use of metformin and GLP-1RA. Linear regression models comparing monthly changes in HbA1c and BMI z-score adjusted for initial BMI z-score and HbA1c, gender, and age. Results: The GLP-1RA group was majority female (GLP-1RA [n=12] 84%, metformin [n=118] 50%). The median age of the entire cohort was 14.6 years [IQR 13.0, 16.5] and study duration was 242 [143, 315] days. Monthly HbA1c change was comparable between the groups: GLP-1RA -0.16 [-0.23, -0.11], metformin -0.11 [-0.23, -0.04]. Monthly BMI z-score change favored the GLP-1RA group: GLP-1RA -0.02 [-0.04, -0.01], metformin -0.01 [-0.02, 0.00]. In regression analysis, GLP1-1RA showed greater reductions of BMI z-score (β = -0.031, p = 0.036) but not HbA1c (β = -0.09, p = 0.35). Conclusion: Compared to metformin, GLP-1RA monotherapy in newly diagnosed YT2D lowered BMI z-score but had comparable effect in HbA1c. A randomized controlled study is needed to validate these preliminary findings. Disclosure I. Tejeji: None. T. Zeier: None. N.T. Chang: Consultant; Novo Nordisk. J. Smith: None. L.C. Chao: None. Funding National Institute of Diabetes and Digestive and Kidney Diseases (1R25DK113652)