Background: The optimal duration of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) among patients at high bleeding risk (HBR) is unknown., Objectives: The purpose of this analysis was to compare 1 vs 3 months of DAPT in HBR patients undergoing drug-eluting stent implantation., Methods: The XIENCE Short DAPT program comprised 3 prospective, multicenter, single-arm studies of HBR patients treated with a short DAPT course followed by aspirin monotherapy after PCI with a cobalt-chromium everolimus-eluting stent. In this exploratory analysis, patients who received 1-month DAPT (XIENCE 28 USA and 28 Global) were compared with those on 3-month DAPT (XIENCE 90) using propensity score stratification. Ischemic and bleeding outcomes were assessed between 1 and 12 months after index PCI., Results: A total of 3,652 patients were enrolled and 1,392 patients after 1-month DAPT and 1,972 patients after 3-month DAPT were eligible for the analyses. The primary endpoint of all-cause mortality or myocardial infarction was similar between the 2 groups (7.3% vs 7.5%; difference -0.2%; 95% CI: -2.2% to 1.7%; P = 0.41). The key secondary endpoint of BARC (Bleeding Academic Research Consortium) type 2-5 bleeding was lower with 1-month DAPT compared with 3-month DAPT (7.6% vs 10.0%; difference -2.5%; 95% CI: -4.6% to -0.3%; P = 0.012). Major BARC type 3-5 bleeding did not differ at 12 months (3.6% vs 4.7%; difference -1.1%; 95% CI: -2.6% to 0.4%; P = 0.082), but was lower with 1-month DAPT at 90 days (1.0% vs 2.1%; P = 0.015)., Conclusions: Among HBR patients undergoing PCI, 1 month of DAPT, compared with 3 months of DAPT, was associated with similar ischemic outcomes and lower bleeding risk. (XIENCE 90 Study; NCT03218787; XIENCE 28 USA Study; NCT03815175; XIENCE 28 Global Study; NCT03355742)., Competing Interests: Funding Support and Author Disclosures The study was sponsored by Abbott. Dr Valgimigli has received grants and personal fees from Terumo; has received personal fees from AstraZeneca, Alvimedica/CID, Abbott Vascular, Daiichi-Sankyo, Bayer, CoreFLOW, Idorsia Pharmaceuticals Ltd, Universität Basel Department Klinische Forschung, and Vifor; and has received personal fees from Bristol Myers Squibb SA, Biotronik, Boston Scientific, Medtronic, Vesalio, Novartis, Chiesi, and PhaseBio, outside of the submitted work. Dr Angiolillo has received consulting fees or honoraria from Abbott, Amgen, Aralez, AstraZeneca, Bayer, Biosensors, Boehringer Ingelheim, Bristol Myers Squibb, Chiesi, Daiichi-Sankyo, Eli Lilly, Haemonetics, Janssen, Merck, PhaseBio, PLx Pharma, Pfizer, Sanofi, and The Medicines Company; has received payments for participation in review activities from CeloNova and St Jude Medical, outside the present work; and his institution has received research grants from Amgen, AstraZeneca, Bayer, Biosensors, CeloNova, CSL Behring, Daiichi-Sankyo, Eisai, Eli Lilly, Gilead, Janssen, Matsutani Chemical Industry Co, Merck, Novartis, Osprey Medical, Renal Guard Solutions, and Scott R. MacKenzie Foundation. Dr Bangalore has received grants from Abbott Vascular; and has received personal fees from Abbott Vascular, Biotronik, Amgen, and Pfizer. Dr Bhatt has served on the advisory board of Cardax, CellProthera, Cereno Scientific, Elsevier Practice Update Cardiology, Janssen, Level Ex, Medscape Cardiology, MyoKardia, Novo Nordisk, PhaseBio, PLx Pharma, and Regado Biosciences; has served on the Board of Directors of Boston VA Research Institute, Society of Cardiovascular Patient Care, and TobeSoft; has served as Chair of the American Heart Association Quality Oversight Committee, NCDR-ACTION Registry Steering Committee, and VA CART Research and Publications Committee; has served on Data Monitoring Committees for Baim Institute for Clinical Research (formerly Harvard Clinical Research Institute, for the PORTICO trial, funded by St Jude Medical, now Abbott), Cleveland Clinic (including for the ExCEED trial, funded by Edwards), Contego Medical (Chair, PERFORMANCE 2), Duke Clinical Research Institute, Mayo Clinic, Mount Sinai School of Medicine (for the ENVISAGE trial, funded by Daiichi-Sankyo), and the Population Health Research Institute; has received honoraria from the American College of Cardiology (Senior Associate Editor, Clinical Trials and News, ACC.org; Vice-Chair, ACC Accreditation Committee), Baim Institute for Clinical Research (formerly Harvard Clinical Research Institute; RE-DUAL PCI clinical trial steering committee funded by Boehringer Ingelheim; AEGIS-II executive committee funded by CSL Behring), Belvoir Publications (Editor-in-Chief, Harvard Heart Letter), Canadian Medical and Surgical Knowledge Translation Research Group (clinical trial steering committees), Duke Clinical Research Institute (clinical trial steering committees, including for the PRONOUNCE trial, funded by Ferring Pharmaceuticals), HMP Global (Editor-in-Chief, Journal of Invasive Cardiology), Journal of the American College of Cardiology (Guest Editor; Associate Editor), K2P (Co-Chair, interdisciplinary curriculum), Level Ex, Medtelligence/ReachMD (CME steering committees), MJH Life Sciences, Population Health Research Institute (for the COMPASS operations committee, publications committee, steering committee, and USA national coleader, funded by Bayer), Slack Publications (Chief Medical Editor, Cardiology Today’s Intervention), Society of Cardiovascular Patient Care (Secretary/Treasurer), and WebMD (CME steering committees); has served as Deputy Editor of Clinical Cardiology; has received research funding from Abbott, Afimmune, Amarin, Amgen, AstraZeneca, Bayer, Boehringer Ingelheim, Bristol Myers Squibb, Cardax, CellProthera, Cereno Scientific, Chiesi, CSL Behring, Eisai, Ethicon, Ferring Pharmaceuticals, Forest Laboratories, Fractyl, Garmin, HLS Therapeutics, Idorsia, Ironwood, Ischemix, Janssen, Lexicon, Lilly, Medtronic, MyoKardia, Novartis, Novo Nordisk, Owkin, Pfizer, PhaseBio, PLx Pharma, Regeneron, Roche, Sanofi, Synaptic, The Medicines Company, and 89Bio; has received royalties from Elsevier (Editor, Cardiovascular Intervention: A Companion to Braunwald’s Heart Disease); has served as Site Co-Investigator for Abbott, Biotronik, Boston Scientific, CSI, St Jude Medical (now Abbott), and Svelte; is a Trustee of the American College of Cardiology; and has performed unfunded research for FlowCo, Merck, and Takeda. Dr Makkar has received research grants from Edwards Lifesciences, Abbott, Medtronic, and Boston Scientific; has served as national Principal Investigator for Portico (Abbott) and Acurate (Boston Scientific) U.S. investigation device exemption trials; has received personal proctoring fees from Edwards Lifesciences; and has received travel support from Edwards Lifesciences, Abbott, and Boston Scientific. Dr Hermiller has received consulting and proctoring fees from Abbott and Edwards; and has received consulting fees from Medtronic. Dr Toelg has received speaker honoraria from Boston Scientific, Abbott Vascular, and Biotronik. Dr Neumann has received grants and/or personal fees from Amgen, Boehringer Ingelheim, Daiichi-Sankyo, Novartis, Pfizer, Biotronik, Edwards Lifesciences, Medtronic, Bayer Healthcare, GlaxoSmithKline, Boston Scientific, and Ferrer. Dr Maksoud has served on the Speakers Bureau of Abbott Vascular, Pfizer, and Bristol Myers Squibb. Dr Chehab has received research grants from Edwards Lifesciences and Abbott; and has received speakers honoraria and/or personal fees from Edwards, Abbott, and Biotronics. Dr Choi has received consulting fees from Medtronic. Dr Campo has received research grants from AstraZeneca, Boston Scientific, Medis, SMT, and Siemens. Dr de la Torre Hernandez has received grants/research supports from Abbott Medical, Biosensors, Bristol Myers Squibb, and Amgen; and he has received honoraria or consultation fees from Boston Scientific, Medtronic, Biotronik, AstraZeneca, and Daiichi-Sankyo. Dr Kunadian has received personal fees/honoraria from Bayer, AstraZeneca, Abbott, Amgen, and Daiichi-Sankyo. Dr Varenne has received personal fees/honoraria from Abbott Vascular, Boston Scientific, Biosensors, and AstraZeneca. Dr Vranckx has received grants and/or personal fees from AstraZeneca, Terumo, Abbott Vascular, Daiichi-Sankyo, Bayer AG, and CLS Behring. Dr Windecker has received research and educational grants to the institution from Abbott, Amgen, AstraZeneca, Bristol Myers Squibb, Bayer, Biotronik, Boston Scientific, Cardinal Health, CardioValve, CSL Behring, Daiichi-Sankyo, Edwards Lifesciences, Guerbet, InfraRedx, Johnson & Johnson, Medicure, Medtronic, Novartis, Polares, OrPha Suisse, Pfizer, Regeneron, Sanofi, Sinomed, Terumo, and V-Wave; has served as unpaid advisory board member and/or unpaid member of the steering/executive group of trials funded by Abbott, Abiomed, Amgen, AstraZeneca, Bristol Myers Squibb, Boston Scientific, Biotronik, Cardiovalve, Edwards Lifesciences, MedAlliance, Medtronic, Novartis, Polares, Sinomed, V-Wave, and Xeltis, but has not received personal payments by pharmaceutical companies or device manufacturers; has served as a member of the steering/executive committee group of several investigator-initiated trials that receive funding by industry without impact on his personal remuneration; and is an unpaid member of the Pfizer Research Award selection committee in Switzerland. Dr Krucoff has received grants and/or personal fees from Abbott Vascular, Biosensors, Boston Scientific, Celonova, Medtronic, OrbusNeich, and Terumo. Dr Mehran has received institutional research grants from Abbott, Abiomed, Applied Therapeutics, Arena, AstraZeneca, Bayer, Biosensors, Boston Scientific, Bristol Myers Squibb, CardiaWave, CellAegis, CERC, Chiesi, Concept Medical, CSL Behring, DSI, Insel Gruppe AG, Medtronic, Novartis Pharmaceuticals, OrbusNeich, Philips, Transverse Medical, and Zoll; has received personal fees from ACC, Boston Scientific, California Institute for Regenerative Medicine, Cine-Med Research, Janssen, WebMD, and SCAI; has received consulting fees paid to the institution from Abbott, Abiomed, AM-Pharma, Alleviant Medical, Bayer, Beth Israel Deaconess, CardiaWave, CeloNova, Chiesi, Concept Medical, DSI, Duke University, Idorsia Pharmaceuticals, Medtronic, Novartis, and Philips; has <1% equity in Applied Therapeutics, Elixir Medical, STEL, and CONTROLRAD (spouse); and has served on the Scientific Advisory Board for AMA and Biosensors (spouse). All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)