Background: Patients with heart failure (HF) have a high burden of symptoms and physical limitations, regardless of ejection fraction (EF). Whether the benefits of SGLT2 (sodium-glucose cotransporter-2) inhibitors on these outcomes vary across the full range of EF remains unclear., Methods: Patient-level data were pooled from the DEFINE-HF trial (Dapagliflozin Effects on Biomarkers, Symptoms, and Functional Status in Patients With Heart Failure With Reduced Ejection Fraction) of 263 participants with reduced EF (≤40%), and PRESERVED-HF trial (Effects of Dapagliflozin on Biomarkers, Symptoms and Functional Status in Patients With Preserved Ejection Fraction Heart Failure) of 324 participants with preserved EF (≥45%). Both were randomized, double-blind 12-week trials of dapagliflozin versus placebo, recruiting participants with New York Heart Association class II or higher and elevated natriuretic peptides. The effect of dapagliflozin on the change in the Kansas City Cardiomyopathy Questionnaire (KCCQ) Clinical Summary Score (CSS) at 12 weeks was tested with ANCOVA adjusted for sex, baseline KCCQ, EF, atrial fibrillation, estimated glomerular filtration rate, and type 2 diabetes. Interaction of dapagliflozin effects on KCCQ-CSS by EF was assessed using EF both categorically and continuously with restricted cubic spline. Responder analyses, examining proportions of patients with deterioration, and clinically meaningful improvements in KCCQ-CSS were conducted using logistic regression., Results: Of 587 patients randomized (293 dapagliflozin, 294 placebo), EF was ≤40, >40-≤60, and >60% in 262 (45%), 199 (34%), and 126 (21%), respectively. Dapagliflozin improved KCCQ-CSS at 12 weeks (placebo-adjusted difference 5.0 points [95% CI, 2.6-7.5]; P <0.001). This was consistent in participants with EF≤40 (4.6 points [95% CI, 1.0-8.1]; P =0.01), >40 to ≤60 (4.9 points [95% CI, 0.8-9.0]; P =0.02) and >60% (6.8 points [95% CI, 1.5-12.1]; P =0.01; P interaction =0.79). Benefits of dapagliflozin on KCCQ-CSS were also consistent when analyzing EF continuously ( P interaction =0.94). In responder analyses, fewer dapagliflozin-treated patients had deterioration and more had small, moderate, and large KCCQ-CSS improvements versus placebo; these results were also consistent regardless of EF (all P interaction values nonsignificant)., Conclusions: In patients with HF, dapagliflozin significantly improves symptoms and physical limitations after 12 weeks of treatment, with consistent and clinically meaningful benefits across the full range of EF., Registration: URL: https://www., Clinicaltrials: gov; Unique identifiers: NCT02653482 and NCT03030235., Competing Interests: Disclosures Dr Nassif is a consultant to Vifor and has received research support from Cytokinetics. Dr Husain reports grant/research support and company relationship at AstraZeneca, Merck, and Novo Nordisk; is a consultant and reports a company relationship at AstraZeneca, Boehringer Ingleheim, Janssen, Merck, Novo Nordisk, and Roche; and has patent pending US61/721,819 (United States), patent US61/719,075 (United States), and patent pending EP2911686A1 (European Patent Office). Dr Borlaug reports grant/research support from the National Institutes of Health/National Heart, Lung, and Blood Institute, the US Department of Defense, Axon, AstraZeneca, Corvia, Medtronic, Novo Nordisk, and Tenax Therapeutics; and consulting/advisory board with Amgen, Aria, Boehringer Ingelheim, Edwards Lifesciences, Eli Lilly, Merck, Novo Nordisk, NGMBio, ShouTi, and VADovations. Dr Kitzman reports receiving honoraria as a consultant for Bayer, Merck, Medtronic, Relypsa, Corvia Medical, Boehringer Ingelheim, Novo Nordisk, AstraZeneca, and Novartis; grant funding from Novartis, Bayer, Novo Nordisk, and AstraZeneca; and has stock ownership in Gilead Sciences. Dr Inzucchi is an advisor/consultant for AstraZeneca, Bayer, Boehringer Ingelheim, Novo Nordisk, Merck, and Pfizer; and lectures for AstraZeneca and Boehringer Ingelheim. Dr McGuire reports research support for Clinical Trials Leadership from Boehringer Ingelheim, Sanofi, Merck & Co, Pfizer, AstraZeneca, Novo Nordisk, Esperion, Lilly USA, Lexicon, and CSL Behring; and honoraria for consultancy from Lilly USA, Boehringer Ingelheim, Merck & Co, Novo Nordisk, Applied Therapeutics, Metavant, Sanofi, Intercept Pharmaceuticals, Altimmune, CSL Behring, and Bayer. Dr Pitt reports consulting fees and company relationship with AstraZeneca, Boehringer Ingelheim, Bayer, Lexicon, Merck, and Phase Bio; consulting fees and/or stock options and company relationship with Vifor, KBP Biosciences, scPharmaceuticals, Cereno Scientific, Tricida, SQinnovation, G-# Pharmaceuticals, Protonintel, and Brainstorm Medical; and patent 9931412 (site-specific delivery of eplerenone to the myocardium; United States) patent pending 63/045,783 (histone-modulating agents for the protection and treatment of organ damage; United States). Dr Scirica reports institutional research grants to Brigham and Women’s Hospital from Better Therapeutics, Boehringer Ingelheim, Merck, Novo Nordisk, and Pfizer; consulting fees from Allergan, Boehringer Ingelheim, Better Therapeutics, Elsevier Practice Update Cardiology, Esperion, Hamni, Lexicon, Lexeo, and Novo Nordisk; and equity in Health [at] Scale and Doximity. Dr Shah reports research grants from the National Institutes of Health (R01 HL107577, R01 HL127028, R01 HL140731, and R01 HL149423), Actelion, AstraZeneca, Corvia, Novartis, and Pfizer; and consulting fees from Abbott, Actelion, AstraZeneca, Amgen, Aria CV, Axon Therapies, Bayer, Boehringer Ingelheim, Boston Scientific, Bristol Myers Squibb, Cardiora, CVRx, Cytokinetics, Edwards Lifesciences, Eidos, Eisai, Imara, Impulse Dynamics, Intellia, Ionis, Ironwood, Lilly, Merck, MyoKardia, Novartis, Novo Nordisk, Pfizer, Prothena, Regeneron, Rivus, Sanofi, Shifamed, Tenax, Tenaya, and United Therapeutics. Dr Umpierrez reports research support to Emory University from AstraZeneca, Dexcom Inc, Baxter, and Bayer (since 2020). Dr Sharma is an advisory board member and consultant for Alleviant, AstraZeneca, Bayer, Boehringer Ingelheim, Bristol Myers Squibb, Cytokinetics, Janssen, Novartis, Novo Nordisk, and RIVUS and receives honoraria. Dr Kosiborod reports grant/research support and company relationship at AstraZeneca, Boehringer Ingelheim, and Pfizer; honoraria and company relationship with AstraZeneca, Boehringer Ingelheim, and Novo Nordisk; consultant and company relationship with 35Pharma, Alnylam, Amgen, Applied Therapeutics, AstraZeneca, Bayer, Boehringer Ingelheim, Cytokinetics, Dexcom, Eli Lilly, Esperion Therapeutics, Imbria Pharmaceuticals, Janssen, Lexicon, Merck (Diabetes and Cardiovascular), Novo Nordisk, Pharmacosmos, Pfizer, scPharmaceuticals, Structure Therapeutics, Vifor Pharma, Youngene Therapeutics; other research support and company relationship with AstraZeneca; and stock options and company relationship with Artera Health, and Saghmos Therapeutics.