The novel dual glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist tirzepatide (TZP) is in development for type 2 diabetes (T2D). Efficacy and safety of once weekly TZP vs. semaglutide (SEMA) was assessed in people with T2D on background metformin. In this open-label, 40-wk Phase 3 study, people with T2D (N=1879; mean baseline [BL] HbA1c 8.28%; age 56.6 y; T2D duration 8.6 y; BMI 34.2 kg/m2) were randomized (1:1:1:1) to TZP (5, 10, 15 mg) or SEMA (1 mg). Primary efficacy objective was noninferiority of TZP 10 and/or 15 mg vs. SEMA for mean change in HbA1c from BL at 40 wk. Secondary objectives included noninferiority (TZP 5 mg) for HbA1c change and superiority (all TZP doses) for change in HbA1c, body weight (BW) and fasting serum glucose (FSG), and proportion of patients with HbA1c Disclosure J. Frias: Consultant; Self; 89bio, Inc., Altimmune, Axcella Health Inc., Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly and Company, Gilead Sciences, Inc., Intercept Pharmaceuticals, Inc., Merck & Co., Inc., Novo Nordisk, Pfizer Inc., Sanofi, Research Support; Self; AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Bristol-Myers Squibb Company, CymaBay Therapeutics, Eli Lilly and Company, Intercept Pharmaceuticals, Inc., Janssen Pharmaceuticals, Inc., Madrigal Pharmaceuticals, Inc., Merck & Co., Inc., Novartis Pharmaceuticals Corporation, Novo Nordisk, Pfizer Inc., Sanofi, Speaker’s Bureau; Self; Merck & Co., Inc., Sanofi. M. J. Davies: Advisory Panel; Self; Boehringer Ingelheim International GmbH, Boehringer Ingelheim Limited (UK), Eli Lilly and Company, Lexicon Pharmaceuticals, Inc., Novo Nordisk A/S, Sanofi, Other Relationship; Self; AstraZeneca, NIHR Leicester Biomedical Research Centre, Novo Nordisk, Speaker’s Bureau; Self; Astra Zeneca Pharma India Ltd, Boehringer Ingelheim (China), Boehringer Ingelheim (Philippines), Inc., Boehringer Ingelheim International GmbH, Boehringer Ingelheim Limited (UK), Boehringer Ingelheim Saudi Arabia Trading, Boehringer Ingelheim Singapore Pte. Ltd, Boehringer Ingelheim Sp. Z o. o., Eli Lilly and Company, Napp Pharmaceuticals, Novo Nordisk, Novo Nordisk A/S, S. C. Sanofi Romania SRL, Sanofi K. K. J. Rosenstock: Board Member; Self; Applied Therapeutics, Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly and Company, Intarcia Therapeutics, Inc., Novo Nordisk, Oramed Pharmaceuticals, Inc., Sanofi, Consultant; Self; Applied Therapeutics, Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly and Company, Intarcia Therapeutics, Inc., Novo Nordisk, Oramed Pharmaceuticals, Inc., Sanofi, Research Support; Self; Applied Therapeutics, AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly and Company, Genentech, Inc., Intarcia Therapeutics, Inc., Lexicon Pharmaceuticals, Inc., Novartis Pharmaceuticals Corporation, Novo Nordisk, Oramed Pharmaceuticals, Inc., Pfizer Inc., REMD Biotherapeutics, Sanofi. F. C. Perez manghi: None. L. Fernandez lando: Employee; Self; Eli Lilly and Company, Stock/Shareholder; Self; Eli Lilly and Company. B. Bergman: Employee; Self; Eli Lilly and Company, Employee; Spouse/Partner; Eli Lilly and Company. B. Liu: Employee; Self; Eli Lilly and Company, Stock/Shareholder; Self; Eli Lilly and Company. X. Cui: Employee; Self; Eli Lilly and Company. K. Brown: Employee; Self; Eli Lilly and Company. Funding Eli Lilly and Company