Conflict of Interest Disclosures: Dr Topalian reported receiving grants from Bristol-Myers Squibb, Compugen, and Potenza Therapeutics during the conduct of the study; receiving travel reimbursements from Bristol-Myers Squibb, Dragonfly Therapeutics, Five Prime Therapeutics, and Merck; receiving consulting fees from AbbVie, Amgen, Avidity NanoMedicines, Bayer, Camden Nexus, DNAtrix, Dragonfly Therapeutics, Dynavax Technologies, Ervaxx, Five Prime Therapeutics, FLX Bio, ImaginAb, Immunomic Therapeutics, Janssen Pharmaceuticals, MedImmune/AstraZeneca, Merck, Pfizer, Rock Springs Capital, and WindMIL outside the submitted work; receiving stock or stock options from Aduro, Dragonfly Therapeutics, Ervaxx, Five Prime Therapeutics, FLX Bio, Jounce Therapeutics, Potenza Therapeutics, Tizona LLC, and WindMIL; having intellectual property licensed through her institution to Bristol-Myers Squibb, Aduro, Immunomic Therapeutics, NexImmune, and WindMIL; and having patents pending for cancer therapy via a combination of epigenetic modulation and immune modulation, checkpoint blockade and microsatellite instability, and biomarkers useful for determining response to PD-1 blockade therapy. Dr Hodi reported receiving other support from Bristol-Myers Squibb to his institution during the conduct of the study; receiving grants from Bristol-Myers Squibb and Novartis; receiving personal fees from Aduro, Apricity, Bayer, Bristol-Myers Squibb, Compass Therapeutics, EMD Serono, Genentech/Roche, Merck, Novartis, Partners Therapeutics, Pionyr, Pfizer, Rheos, Sanofi, Surface, Takeda, Torque, and Verastem outside the submitted work; and having a patent to Methods for Treating MIA-related Disorders (#20100111973) pending and royalties paid, a patent to Tumor Antigens and Uses Thereof (#7250291) issued, a patent to Compositions and Methods for Identification, Assessment, Prevention, and Treatment of Melanoma Using PD-L1 Isoforms (#20160340407) pending, patents to Therapeutic Peptides (#20160046716, #20240004112, #20170022275, and #20170008962) pending, a patent to Therapeutic Peptides issued, and a patent to Methods of Using Pembrolizumab and Trebananib pending. Dr Brahmer reported receiving grants and having an uncompensated advisory committee/consulting agreement with Bristol-Myers Squibb during conduct of the study; personal fees from Amgen, AstraZeneca/MedImmune, Celgene, Genentech, Janssen Oncology, Eli Lilly, Merck, and Syndax outside the submitted work; serving on the advisory council from Amgen; consulting agreement from Celgene, Eli Lilly, and Merck; serving on the advisory board from AstraZeneca, Genentech, Janssen Oncology, Merck, and Syndax; and receiving grant support from AstraZeneca/MedImmune and Merck. Dr Gettinger reported receiving other support from Bristol-Myers Squibb outside the submitted work. Dr Smith reported receiving grant support from Bristol-Myers Squibb (Medarex) during the conduct of the study and from Astellas, Bayer, Celgene, Incyte, Eli Lilly, ESSA, F. Hoffmann-LaRoche AG, Genentech, Incyte, MedImmune, Medivation (Pfizer), Merck, Millennium, Novartis, OncoMed, and Seattle Genetics outside the submitted work. Dr McDermott reported receiving grant support and personal fees from Bristol-Myers Squibb during the conduct of the study and receiving honoraria for consulting from Array BioPharm, Bristol-Myers Squibb, Eisai, Exelixis, Genentech BioOncology, Jounce Therapeutics, Merck, Novartis, Pfizer, and Prometheus outside the submitted work. Dr Powderly reported other support from Bristol-Myers Squibb during the conduct of the study; receiving other support from Alkermes, Arcus, AstraZeneca/MedImmune, Corvus, Curis, EMD Serono, FLX Bio, Genentech, InCyte, MacroGenics, Merck, Tempest, and Top Alliance BioSciences outside the submitted work; and having a patent pending and reported being founder and owner of Carolina BioOncology Institute, PLLC, an independent Phase I Cancer Research Clinic and BioCytics Inc, a Human Applications laboratory developing cellular immunotherapies (both companies collaborate with multiple potential biopharma and biotech partners to develop future cellular immunotherapies). Dr Sosman reported receiving personal fees from Bristol-Myers Squibb, Curis, and Genentech outside the submitted work. Dr Atkins reported receiving research support (to the institution) from Bristol-Myers Squibb, Merck, Pfizer and Genentech; serving as a consultant or advisor at Bristol-Myers Squibb, Merck, Novartis, Pfizer, Genentech/Roche, Exelixis, Eisai, Aveo, Array, Arrowhead, AstraZeneca, Ideera, Aduro, ImmunoCore, Boehringer Ingelheim, Iovance, Newlink, Surface, Alexion, Acceleron, Lynx, Cota, Amgen, Galactone, Werewolf, Fathom, Pneuma, and Leads; and having stock options in Werewolf and Pyxis Oncology outside the submitted work. Dr Leming reported receiving consulting fees from Bristol-Myers Squibb for participation in an unrelated consensus panel. Dr Spigel reported receiving grants and other support from Bristol-Myers Squibb during the conduct of the study; having a leadership role at Centennial Medical Center; serving as a consultant or advisor at AbbVie, Amgen, AstraZeneca, Boehringer Ingelheim, Celgene, Evelo, Foundation Medicine, GlaxoSmithKline, Genentech/Roche, Illumina, Eli Lilly, Merck, Moderna Therapeutics, Nektar, Novartis, Pfizer, PharmaMar, Precision Oncology, Takeda, and TRM Oncology; receiving research funding (payments to institution) from AbbVie, Acerta Pharma, Aeglea Biotherapeutics, Amgen, ARMO Biosciences, Astellas, Boehringer Ingelheim, Celgene, Celldex, Clovis Oncology, Daiichi Sankyo, EMD Serono, Foundation Medicine, G1 Therapeutics, Genentech/Roche, Novartis, GlaxoSmithKline, GRAIL, Ipsen, Eli Lilly, Millennium, Nektar, Neon Therapeutics, Oncogenex, Pfizer, Takeda, Tesaro, Transgene, and UT Southwestern; and receiving reimbursement for accommodations, expenses and travel from AstraZeneca, Boehringer Ingelheim, Celgene, EMD Serono, Genentech, Genzyme, Intuitive Surgical, Eli Lilly, Merck, Pfizer, Purdue Pharma, Spectrum Pharmaceuticals, and Sysmex. Dr Antonia reported receiving grants and personal fees from Bristol-Myers Squibb during the conduct of the study; receiving grants from AstraZeneca; receiving personal fees from Amgen, Boehringer Ingelheim, CBMG, Celsius, FLX Bio, Genentech, MedImmune, Memgen, Merck, Multivir, and Venn outside the submitted work; and holding a patent to p53-DC vaccine issues and license and a patent to oncolytic virus pending. Dr Drilon reported receiving personal fees from Ariad, AstraZeneca, Bayer, BeiGene, BergenBio, Blueprint Medicines, Exelixis, Genentech, Helsinn, Hengrui, Ignyta, Loxo, Millenium, MORE Health, Pfizer, Roche, Takeda, TP Therapeutics, Tyra, and Verastem during the conduct of the study; receiving other support from GlaxoSmithKline, Taiho, and Teva outside the submitted work; receiving royalties from Wolters Kluwer for Pocket Medicine; receiving research funding from Foundation Medicine; receiving food and beverage from Merck and Puma; and receiving continuing medical education honoraria from Medscape, OncLive, PeerVoice, Physicians Education Resources, Targeted Oncology, and Research to Practice all outside the submitted work. Dr Wolchok reported receiving grants and personal fees from Bristol-Myers Squibb during the conduct of the study; receiving grants from Bristol-Myers Squibb, MedImmune, and Genentech; receiving personal fees from Adaptive Biotech, Advaxis, Amgen, Apricity, Array BioPharma, Ascentage Pharma, Astellas, Bayer, BeiGene, Bristol-Myers Squibb, Celgene, Chugai, Elucida, Eli Lilly, Esanex, F Star, Genentech, Imvaq, Janssen, Kleo Pharma, Linneaus, MedImmune, Merck, Neon Therapuetics, Ono, Polaris Pharma, Polynoma, Psioxus, Puretech, Recepta, Trieza, Sellas Life Sciences, Serametrix, Surface Oncology, and Syndax outside the submitted work; and owning equity in Potenza Therapeutics, Tizona Pharmaceuticals, Adaptive Biotechnologies, Elucida, Imvaq, BeiGene, Trieza, and Linneaus. Dr Carvajal reported receiving grants and personal fees from Bristol-Myers Squibb during the conduct of the study; receiving grants from Amgen, Astellis, AstraZeneca, Aura Biosciences, Bayer, Bellicum, Corvus, Incyte, Eli Lilly, Macrogenics, Merck, Mirati, Novartis, Roche/Genentech, Pfizer, and Plexxikon outside the submitted work; and receiving personal fees from Aura Biosciences, Chimeron, Incyte, Merck, PureTech, Regenix, Sanofi Genzyme, and Sorrento Therapeutics outside the submitted work. Drs McHenry, Harbison, and Hosein reported stock ownership and employment by Bristol-Myers Squibb. Dr Grosso reported employment by Bristol-Myers Squibb. Dr Sznol reported receiving other support from Bristol-Myers Squibb during the conduct of the study; receiving other support from Amphivena, Adaptive Biotechnologies, Intensity, Actym, Nextcure, and Torque; and receiving consulting fees from Bristol-Myers Squibb, Roche/Genentech, AstraZeneca/Medimmune, Pfizer, Novartis, Kyowa-Kirin, Seattle Genetics, Nektar, Pierre-Fabre, Eli Lilly, Merck US, Teravance, Biodesix, Vaccinex, Janssen, Modulate Therapeutics, Baxalta-Shire, Incyte, Newlink Genetics, Iovance, Agonox, Arbutus, Celldex, Inovio, Gritstone, Molecular Partners, Innate Pharma, AbbVie, Immunocore, Genmab, Almac, Hinge, Allakos, Anaeropharma, Array, GI Innovation, Genocea, Chugai-Roche, Symphogen, Adaptimmune, Omniox, Lycera, and Pieris outside the submitted work. No other disclosures were reported.