Purpose: CAPTIVATE (NCT02910583), a randomized phase II study, evaluates minimal residual disease (MRD)-guided treatment discontinuation following completion of first-line ibrutinib plus venetoclax treatment in patients with chronic lymphocytic leukemia (CLL)., Methods: Previously untreated CLL patients age < 70 years received three cycles of ibrutinib and then 12 cycles of combined ibrutinib plus venetoclax. Patients in the MRD cohort who met the stringent random assignment criteria for confirmed undetectable MRD (Confirmed uMRD) were randomly assigned 1:1 to double-blind placebo or ibrutinib; patients without Confirmed uMRD (uMRD Not Confirmed) were randomly assigned 1:1 to open-label ibrutinib or ibrutinib plus venetoclax. Primary end point was 1-year disease-free survival (DFS) rate with placebo versus ibrutinib in the Confirmed uMRD population. Secondary end points included response rates, uMRD, and safety., Results: One hundred sixty-four patients initiated three cycles of ibrutinib lead-in. After 12 cycles of ibrutinib plus venetoclax, best uMRD response rates were 75% (peripheral blood) and 68% (bone marrow). Patients with Confirmed uMRD were randomly assigned to receive placebo (n = 43) or ibrutinib (n = 43); patients with uMRD Not Confirmed were randomly assigned to ibrutinib (n = 31) or ibrutinib plus venetoclax (n = 32). Median follow-up was 31.3 months. One-year DFS rate was not significantly different between placebo (95%) and ibrutinib (100%; arm difference: 4.7% [95% CI, -1.6 to 10.9]; P = .15) in the Confirmed uMRD population. After ibrutinib lead-in tumor debulking, 36 of 40 patients (90%) with high tumor lysis syndrome risk at baseline shifted to medium or low tumor lysis syndrome risk categories. Adverse events were most frequent during the first 6 months of ibrutinib plus venetoclax and generally decreased over time., Conclusion: The 1-year DFS rate of 95% in placebo-randomly assigned patients with Confirmed uMRD suggests the potential for fixed-duration treatment with this all-oral, once-daily, chemotherapy-free regimen in first-line CLL., Competing Interests: William G. WierdaConsulting or Advisory Role: SanofiResearch Funding: GlaxoSmithKline/Novartis, AbbVie, Genentech, Pharmacyclics, Acerta Pharma, Gilead Sciences, Janssen, Juno Therapeutics, Kite, a Gilead Company, Oncternal Therapeutics, Loxo, Xencor, miRagen, Sunesis Pharmaceuticals, Cyclacel John N. AllanHonoraria: AstraZeneca, AbbVie, Pharmacyclics/Janssen, BeiGeneConsulting/Advisory Role: AbbVie/Genentech, Pharmacyclics, Ascentage Pharma, BeiGene, Janssen Oncology, Epizyme, AstraZeneca, TG Therapeutics, ADC TherapeuticsResearch Funding: Genentech, Janssen, Celgene, TG Therapeutics Tanya SiddiqiConsulting/Advisory Role: Juno Therapeutics, AstraZeneca, BeiGene, Celgene, Pharmacyclics, Bristol Myers Squibb/Celgene, Pharmacyclics/JanssenSpeakers Bureau: Pharmacyclics/Janssen, AstraZeneca, BeiGene, Bristol Myers Squibb/CelgeneResearch Funding: Juno Therapeutics (Inst), Kite, a Gilead Company (Inst), Acerta Pharma (Inst), TG Therapeutics (Inst), BeiGene (Inst), Pharmacyclics (Inst), Celgene (Inst), Oncternal Therapeutics (Inst) Thomas J. KippsEmployment: Moores Cancer CenterStock and Other Ownership Interests: Oncternal TherapeuticsHonoraria: Pharmacyclics, AbbVie, Janssen, Genentech, Gilead Sciences, DAVAOncology, AstraZenecaConsulting/Advisory Role: AbbVie, Pharmacyclics, Genentech, Janssen, DAVAOncologySpeakers Bureau: Verastem/Pharmacyclics, Pharmacyclics/Janssen, AbbVie/Genentech, Gilead Sciences, DAVA PharmaceuticalsResearch Funding: Pharmacyclics/Janssen (Inst), Breast Cancer Research Foundation (Inst), Oncternal Therapeutics (Inst), Leukemia and Lymphoma Society (Inst), California Institute for Regenerative Medicine (CIRM) (Inst), National Cancer Institute (Inst), NIH (Inst)Patents, Royalties, Other Intellectual Property: Cirmtuzumab was developed by Thomas J. Kipps in the Thomas J. Kipps laboratory and licensed by the University of California to Oncternal Therapeutics, Inc, which provided stock options and research funding to the Thomas J. Kipps laboratory. (Inst)Travel, Accommodations, Expenses: AbbVie/Pharmacyclics, Genentech/Roche, Janssen, Gilead Sciences, Celgene, DAVAOncology, Breast Cancer Research Foundation, TG Therapeutics, Verastem, AstraZeneca Stephen OpatHonoraria: AbbVie, AstraZeneca, Janssen, Roche, Gilead Sciences, Mundipharma, Takeda, Merck, and CSL BehringConsulting/Advisory Role: AbbVie, AstraZeneca, Janssen, Celgene, Novartis, Gilead Sciences, Takeda, Merck, Mundipharma, CSL BehringResearch Funding: AstraZeneca (Inst), BeiGene (Inst), Roche (Inst), AbbVie (Inst), Gilead Sciences (Inst), Takeda (Inst), Pharmacyclics (Inst), Janssen (Inst), Celgene (Inst), Merck (Inst), Epizyme (Inst)Travel, Accommodations, Expenses: Roche Alessandra TedeschiConsulting/Advisory Role: Janssen, BeiGene, AstraZeneca, AbbVieSpeakers Bureau: AbbVie, AstraZeneca, Janssen, BeiGene Xavier C. BadouxHonoraria: Janssen/Pharmacyclics, AbbVie Bryone J. KussStock and Other Ownership Interests: Commonwealth Serum Laboratories (CSL)Honoraria: Roche, Janssen Oncology, AstraZeneca, AbbVie, Merck, Mundipharma, Takeda, SandozConsulting/Advisory Role: AbbVie, Janssen Oncology, Kyowa Kirin International, AstraZenecaSpeakers Bureau: AstraZeneca, Janssen-Ortho Sharon JacksonHonoraria: AbbVie NZ LtdConsulting/Advisory Role: AbbVie NZSpeakers Bureau: AbbVie NZTravel, Accommodations, Expenses: Roche NZ Carol MorenoConsulting/Advisory Role: Janssen Oncology, Abbott/AbbVie, AstraZeneca, BieGeneSpeakers Bureau: Janssen OncologyResearch Funding: AbbVie Ryan JacobsConsulting/Advisory Role: AstraZeneca, Janssen Oncology, Secura Bio, Genentech, Adaptive Biotechnologies, ADC Therapeutics, TG TherapeuticsSpeakers Bureau: Pharmacyclics, Janssen Oncology, AbbVie, TG Therapeutics, AstraZenecaResearch Funding: TeneoBio (Inst), Pharmacyclics (Inst), TG Therapeutics (Inst), MEI Pharma (Inst) John M. PagelConsulting/Advisory Role: Gilead Sciences, AstraZeneca, Actinium Pharmaceuticals, BeiGene, Loxo, MEI Pharma, TG Therapeutics, MorphoSys, Epizyme Ian FlinnConsulting/advisory role: AbbVie (Inst), Seattle Genetics (Inst), TG Therapeutics (Inst), Verastem (Inst), Roche (Inst), Gilead Sciences (Inst), Kite, a Gilead Company (Inst), Janssen (Inst), BeiGene (Inst), Takeda (Inst), AstraZeneca (Inst), Juno Therapeutics (Inst), Unum Therapeutics (Inst), MorphoSys (Inst), Nurix (Inst), Shanghai Yingli Pharmaceuticals (Inst), Genentech (Inst), Great Point Partners (Inst), Iksuda Therapeutics (Inst), Novartis (Inst), Pharmacyclics (Inst), Century Therapeutics (Inst), Hutchison MediPharma (Inst), Servier (Inst), Vincerx (Inst)Research Funding: Acerta Pharma (Inst), Agios (Inst), Calithera Biosciences (Inst), Celgene (Inst), Constellation Pharmaceuticals (Inst), Genentech (Inst), Gilead Sciences (Inst), Incyte (Inst), Infinity Pharmaceuticals (Inst), Janssen (Inst), Karyopharm Therapeutics (Inst), Kite, a Gilead Company (Inst), Novartis (Inst), Pharmacyclics (Inst), Portola Pharmaceuticals (Inst), Roche (Inst), TG Therapeutics (Inst), Trillium Therapeutics (Inst), AbbVie (Inst), ArQule (Inst), BeiGene (Inst), Curis (Inst), Forma Therapeutics (Inst), Forty Seven (Inst), Merck (Inst), Pfizer (Inst), Takeda (Inst), Teva (Inst), Verastem (Inst), AstraZeneca (Inst), Juno Therapeutics (Inst), Unum Therapeutics (Inst), MorphoSys (Inst), Seattle Genetics (Inst), IGM Biosciences (Inst), Loxo (Inst), Rhizen Pharmaceuticals (Inst), Triact Therapeutics (Inst) Yvonne PakEmployment: BridgeBio Pharma, AbbVieStock and Other Ownership Interests: BridgeBio Pharma, AbbVie Cathy ZhouEmployment: Abbvie/PharmacyclicsStock and Other Ownership Interests: Abbvie/Pharmacyclics Edith Szafer-GlusmanStock and Other Ownership Interests: AbbVie Joi NinomotoEmployment: AbbVieStock and Other Ownership Interests: AbbVie James P. DeanEmployment: PharmacyclicsStock and Other Ownership Interests: AbbVie Danelle F. JamesEmployment: Abbvie/PharmacyclicsLeadership: Abbvie/PharmacyclicsStock and Other Ownership Interests: AbbVie/PharmacyclicsPatents, Royalties, Other Intellectual Property: AbbVie/PharmacyclicsTravel, Accommodations, Expenses: Abbvie/Pharmacyclics Paolo GhiaHonoraria: AbbVie, BeiGene, Janssen Oncology, Gilead Sciences, Juno Therapeutics, Sunesis Pharmaceuticals, ArQule, Adaptive Biotechnologies, Dynamo Therapeutics, MEI Pharma, Acerta Pharma/AstraZeneca, Juno/Celgene/Bristol Myers Squibb, MSD, Lilly, RocheConsulting/Advisory Role: AbbVie, BieGene, Janssen, Gilead Sciences, Sunesis Pharmaceuticals, Juno Therapeutics, ArQule, Adaptive Biotechnologies, Dynamo Therapeutics, MEI Pharma, Acerta Pharma/AstraZeneca, MSD, Lilly, RocheResearch Funding: AbbVie, Janssen Oncology, Gilead Sciences, Sunesis Pharmaceuticals, Novartis, AstraZeneca Constantine S. TamHonoraria: Janssen-Cilag, AbbVie, Novartis, BeiGene, PharmacyclicsConsulting/Advisory Role: Janssen, Loxo, Roche, BeiGene, AbbVieResearch Funding: Janssen-Cilag, AbbVieNo other potential conflicts of interest were reported.