Bartlett, Nancy L.

LBA7564 Background: Patients with r/r B-NHL have a dismal prognosis. DIAL (Dual Immunomodulation in Aggressive Lymphoma) was a multi-center randomized phase II study testing the efficacy of nivolumab (PD-1 inhibitor) plus varlilumab (CD27 agonist) in this population. Methods: Patients were randomized (1:1) to nivolumab (240 mg IV every 2 weeks for 4 months, 480 mg IV monthly thereafter; group 1) alone or combined with varlilumab (3 mg/kg IV monthly; group 2). Cross-over (group 1 to 2) was allowed for progression. Primary endpoint was overall response (ORR) per LYRIC criteria. A sample size of 48 patients per arm would provide 80% power to detect increase in ORR from 25% to 45% using a one-sided test (p = 0.15). Pre-specified interim analysis occurred after half of the patients completed first radiologic assessment. Secondary endpoints included overall survival (OS), progression-free survival (PFS), and adverse events (AEs). Exploratory endpoints included tumor genomic assessment and immune profiling of blood and tumor. Results: 53 patients were enrolled (27 in group 1; 26 in group 2). Interim analysis included 24 patients from each arm. Mean age was 65.2 years, 34 (70.8%) were male, and 36 (75%) received prior CAR-T cell therapy. Baseline characteristics were balanced between arms. Grade ≥ 3 AEs were observed in 8 (33.3%) and 7 (30.4%) of patients in groups 1 and 2, respectively. Common AEs (> 5%) of any grade included fatigue, lymphopenia, diarrhea, rash. There were no treatment-associated deaths. Toxicity profile was similar between arms. Table summarizes efficacy outcomes. ORR was achieved in 6 patients (12.5%), not statistically different between arms; 4 responses were complete. Seven patients crossed over (1 responded after crossing). Median OS (8.6 vs 7.3 months; p = 0.39) and PFS (2.7 vs 1.4 months; p = 0.06) were similar between arms. Subgroup analysis of patients with prior CAR-T cell therapy showed similar ORR (5/36; 14%), not statistically different between arms. Correlative analysis results will be presented at conference. The trial met futility criterion on interim analysis and enrollment ceased based on pre-specified stopping rule. Conclusions: Dual immunomodulatory therapy did not enhance anti-tumor activity in patients with aggressive B-NHL compared to nivolumab alone. Response rates were low and consistent with previous data using PD-1 inhibitors in this population. Prior therapy with CAR-T cell does not seem to sensitize patients to PD-1 blockade. Toxicity profile was acceptable and dual therapy did not increase the rate of AEs. Clinical trial information: NCT03038672. [Table: see text]

7559 Background: Patients (pts) with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) who relapse after or are ineligible for hematopoietic stem cell transplant (HSCT) or chimeric antigen receptor T cell (CAR-T) therapy generally have poor outcomes. Preclinical data provide the rationale for combining brentuximab vedotin (BV), lenalidomide (len), and rituximab for the treatment of R/R DLBCL. BV+len showed promising clinical activity in a Phase 1 trial with a 57% overall response rate (ORR), 10.2-month median progression-free survival, and 14.3-month overall survival (Ward 2021). We report the results of the open-label safety run-in that was conducted prior to the randomized portion of the study. Methods: ECHELON-3 (NCT04404283) is a randomized, double-blind, placebo-controlled, active-comparator, multicenter Phase 3 study. Prior to randomization, an open-label safety run-in was conducted; pts received BV (1.2 mg/kg) and rituximab (375 mg/m2) both q3w, and len 20 mg qd. Pts must have received ≥2 prior lines of therapy and be previously treated with or were ineligible for HSCT or CAR-T, ECOG score ≤2, and PET-avid, bidimensional measurable disease ( > 1.5 cm by CT). Pts with negligible CD30 expression ( < 1%) were eligible. Response was assessed by the investigator according to the Lugano Classification Revised Staging System (Cheson 2014). Results: 10 pts with R/R DLBCL were enrolled. Median age was 70.5 years, 7 pts were male, and all had an ECOG ≤1. Median prior lines of therapy was 3 (range, 2 to 6); no pts received prior HSCT and 6 pts received prior CAR-T. At a median follow-up of 6.9 months (range, 2.3 to 14.1), the most common treatment emergent adverse events (TEAE) were fatigue (n = 5), anemia (n = 4) and constipation (n = 4). Grade ≥3 events were experienced by 8 pts, most commonly anemia and pneumonia (n = 3 each), and neutropenia and thrombocytopenia (n = 2 each). Serious adverse events were observed in 7 pts. Seven pts each had BV and rituximab dose modifications, and 6 pts had a len dose modification. The most common reasons for any dose modification were anemia (n = 3), neutropenia, peripheral neuropathy, or pneumonia (n = 2 each). 4 pts discontinued treatment due to an AE, 2 of which were treatment related (n = 1 each of Grade 2 fatigue; Grade 3 anemia). There was 1 death due to a TEAE that was not treatment related. The ORR (best response) was 70%, including 4 pts with a complete metabolic response, 2 pts with a partial metabolic response, and 3 pts with progressive disease. Responses were seen in both CD30 (+) and (-) pts, as well as in 4 pts who received prior CAR-T. Conclusions: This novel triplet regimen appears active in R/R DLBCL with an acceptable safety profile. The randomized portion of the study is currently enrolling. Clinical trial information: NCT04404283.

7503 Background: To date, an overall survival (OS) benefit from upfront treatment for new treatment combinations over existing approaches has rarely been shown in first-line classical Hodgkin lymphoma (cHL). With the introduction of newer active therapies for relapsed/refractory disease, demonstration of improved OS with first-line therapy has been challenging. In ECHELON-1 (NCT01712490), 5-year follow-up analyses supported the long-term progression-free survival (PFS) benefit with first-line brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine (A+AVD) vs doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) in patients (pts) with stage III/IV cHL, independent of interim positron emission tomography status. A+AVD had a manageable long-term safety profile, with numerically fewer second malignancies and a greater number of pregnancies reported vs ABVD (Connors et al, NEJM 2018; Straus et al, Lancet Haematol 2021). We report a prespecified OS analysis after approximately 6 years’ follow-up (cut-off, June 1, 2021). Methods: Pts were randomized 1:1 to receive up to 6 cycles of A+AVD (n = 664) or ABVD (n = 670) on day 1 and 15 every 28 days. OS was the key secondary endpoint and was an event-driven, pre-specified, alpha-controlled analysis in the intention to treat population. Results: At a median follow-up of 73 months, 39 and 64 OS events occurred in A+AVD and ABVD arms, respectively: OS significantly favored A+AVD vs ABVD (HR 0.590; 95% confidence interval [CI] 0.396–0.879; p = 0.009). Estimated 6-year OS rates (95% CI) were 93.9% (91.6–95.5) vs 89.4% (86.6–91.7) with A+AVD vs ABVD, respectively. There was a consistent OS benefit for A+AVD vs ABVD across prespecified subgroups. The 6-year PFS estimate was 82.3% (79.1–85.0) vs 74.5% (70.8–77.7) with A+AVD vs ABVD, respectively (HR 0.678 [95% CI 0.532–0.863]). Overall, A+AVD had a comparable long-term safety profile to ABVD. Treatment-emergent peripheral neuropathy continued to resolve or improve in both arms, with 86% (379/443) and 87% (249/286) of cases in the A+AVD and ABVD arms either completely resolving (72% vs 79%) or improving (14% vs 8%) by last follow-up. Fewer second malignancies were reported in the A+AVD vs ABVD arm (23 vs 32). More female patients reported pregnancy (49 vs 28) or live births (42 vs 19 in females) in the A+AVD vs the ABVD arm; no stillbirths were reported. No new safety signals were identified. Conclusions: A+AVD treatment resulted in a statistically significant 41% reduction in the risk of death vs ABVD, with a manageable safety profile consistent with prior reports. These outcomes confirm A+AVD as a preferred option for pts with previously untreated stage III/IV cHL. Clinical trial information: NCT01712490.

Abstract Recent first-line randomized controlled trials (RCTs) for patients with diffuse large B-cell lymphoma (DLBCL) have shown negative results, which may be due in part to onerous eligibility criteria limiting enrollment of poor-risk patients who require immediate treatment. We conducted a Delphi-method survey with lymphoma experts in the United States to define recommendations for essential and potentially unnecessary enrollment criteria for modern first-line DLBCL RCTs aimed at increasing clinical diversity of ensuing study groups. We first tabulated enrollment criteria from 19 DLBCL RCTs spanning the rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) era to identify common eligibility criteria from prior DLBCL RCTs for inclusion in the Delphi-method survey. We tabulated 451 total eligibility criteria comprising 51 criterion categories across 19 first-line DLBCL RCTs in the R-CHOP era. We then surveyed lymphoma clinical trial experts representing 8 academic medical centers in the United States regarding essential and unnecessary eligibility criteria for modern DLBCL RCTs. Seventeen of 29 invited clinical investigators completed the round-1 questionnaire (response rate, of 58.6%), 15 of 17 round-1 participants (88.2%) completed the round-2 survey, and all round-1 participants reviewed finalized recommendations for eligibility criteria for modern first-line DLBCL RCTs. We defined consensus recommendations for 31 modernized eligibility criteria including threshold values for 10 quantitative eligibility criteria aimed at facilitating enrollment of a clinically diverse study population in first-line DLBCL RCTs designed to improve standard-of-care therapy.

Abstract Background: High grade B-cell Lymphoma with rearrangements of MYC and BCL2 and/or BCL6, also known as double hit lymphoma (DHL), and double expressing lymphomas (DEL; DLBCL with IHC expression of MYC and BCL2, but without double hit cytogenetics) are highly aggressive B cell non-Hodgkin lymphomas and patients (pts) often develop relapsed/refractory disease following standard first-line chemoimmunotherapy. DA-EPOCH-R is widely used in patients with DHL, and a phase 1 trial of venetoclax + DA-EPOCH-R established the dose of 600 mg for 5 days with each cycle as the recommended phase 2 dose (Rutherford, et al. Proc ASCO 2020). A051701 is a phase II/III randomized trial evaluating chemoimmunotherapy +/- the BCL2 inhibitor venetoclax in a DHL cohort (pts with DHL with BCL2 rearrangement and/or expression), and a DEL cohort. Here we report the initial results from the DHL cohort of A051701. Methods: Pts age ≥ 18 years with newly diagnosed DHL were stratified on International Prognostic Index (IPI) score and receipt of a single cycle of chemotherapy prior to registration, which was permitted, and randomized 1:1 to receive DA-EPOCH-R (Arm 1) or DA-EPOCH-R with venetoclax (Arm 2). Enrollment was based on local pathology results which were centrally confirmed. DA-EPOCH-R was administered as previously published. Venetoclax was dosed at 600 mg po daily on days 4-8 of cycle 1 and on days 1-5 of subsequent cycles for up to 6 total cycles. All cycles were supported by GCSF or peg-GCSF. For the interim analysis at the end of phase II, 53 events ensured 90% power to detect an improvement in 24-month progression-free survival (PFS) from 40% in Arm 1 to 60% in Arm 2 (HR=0.557) using a one-sided stratified log-rank test with type I error rate of 20%. The Alliance Data and Safety Monitoring Board approved the data release after accrual was stopped early due to excess toxicity in Arm 2. These data were frozen July 8, 2021. Results: 73 pts were registered (36 in Arm 1 and 37 in Arm 2) between 8/7/19 and 9/18/20. Analyses were performed for the modified intent-to-treat (mITT) population, defined as eligible pts with DHL histology confirmed (n=66; 30 Arm 1, 36 Arm 2). Median age was 65 years in both arms (range 37-80) and baseline demographic factors were well balanced. An allowed pre-protocol chemoimmunotherapy cycle was administered in 60% and 56% of Arm 1 and Arm 2 pts, respectively. The majority of pts had advanced stage disease (Arm 1 87%, Arm 2 86%), GCB immunophenotype (Arm 1 100%, Arm 2 88%), ECOG PS 0-1 (Arm 1 90%, Arm 2 86%), and high-intermediate/high risk IPI score (Arm 1 63%, Arm 2 64%). Therapy was completed per protocol in 70% and 47% of pts, respectively, for Arm 1 and 2, and disease progression on therapy occurred in 10% and 3%. Treatment was discontinued due to adverse events in 7% of pts in Arm 1 and 11% of pts in Arm 2. Consent was withdrawn after beginning treatment in 3% and 11% in Arm 1 and 2, respectively. Death on treatment occurred in 1 patient (3%; PJP pneumonia) in Arm 1 and 6 pts (17%; sepsis (n=4), cardiac arrest (n=2)) in Arm 2. The observation of excess deaths on Arm 2 prompted suspension of accrual to the DHL cohort. Treatment was discontinued for other reasons in 3 (10%) and 4 (11%) pts in Arms 1 and 2, respectively. Venetoclax was dose-reduced and/or omitted in 15 (42%) pts. Grade 4 neutropenia was not significantly different between arms (Arm 1 67%, Arm 2 71%), nor was grade ≥3 neutropenic fever (Arm 1 36%, Arm 2 40%). Sepsis occurred more frequently in Arm 2 (14% vs. 23%). The end of treatment overall and complete response rates in the mITT population were 73% and 67% in Arm 1, and 58% and 50% in Arm 2. The end of treatment overall and complete response rates among only pts evaluated for response (n=52) were 79% and 71% in Arm 1, and 88% and 75% in Arm 2. With a median follow-up of 7.4 months, the median PFS was not reached (NR) in Arm 1 (95% CI 6.1-NR) and was 6.7 months in Arm 2 (95% CI 4.5-NR) (two-sided p=0.13). The median OS was NR in Arm 1 and was 8.5 months in Arm 2 (95% CI 5.2-NR) (two-sided p=0.004). Conclusions: DA-EPOCH-R plus venetoclax in DHL pts resulted in excess treatment-related mortality compared to DA-EPOCH-R alone, prompting early discontinuation of accrual and venetoclax treatment for the study cohort. Based on these data, we recommend against combining venetoclax with DA-EPOCH-R in DHL. Robust accrual to this study shows that prospective trials are feasible in DHL, and the favorable outcome thus far in the DA-EPOCH-R arm may serve as a benchmark for future trials Figure 1 Figure 1. Disclosures Abramson: Astra-Zeneca: Consultancy; Allogene Therapeutics: Consultancy; Incyte Corporation: Consultancy; BeiGene: Consultancy; Kymera: Consultancy; Bluebird Bio: Consultancy; Genmab: Consultancy; EMD Serono: Consultancy; Bristol-Myers Squibb Company: Consultancy, Research Funding; C4 Therapeutics: Consultancy; Morphosys: Consultancy; Kite Pharma: Consultancy; Novartis: Consultancy; Seagen Inc.: Research Funding; AbbVie: Consultancy; Karyopharm: Consultancy; Genentech: Consultancy. Ruppert: Telios Pharma: Consultancy. Hsi: Seattle Genetics: Honoraria; Cytomx: Honoraria; Eli Lilly: Research Funding; AbbVie: Research Funding. Landsburg: Triphase: Research Funding; Takeda: Research Funding; Curis: Research Funding; Karyopharm: Membership on an entity's Board of Directors or advisory committees, Other: DSMB member; ADCT: Membership on an entity's Board of Directors or advisory committees; Incyte: Membership on an entity's Board of Directors or advisory committees; Morphosys: Membership on an entity's Board of Directors or advisory committees. Kahl: AbbVie, Adaptive, ADCT, AstraZeneca, Bayer, BeiGene, Bristol-Myers Squibb, Celgene, Genentech, Incyte, Janssen, Karyopharm, Kite, MEI, Pharmacyclics, Roche, TG Therapeutics, and Teva: Consultancy; AbbVie, Acerta, ADCT, AstraZeneca, BeiGene, Genentech: Research Funding. Friedberg: Acerta: Other: DSMC ; Novartis: Other: DSMC ; Bayer: Other: DSMC . Bartlett: Millennium: Research Funding; Janssen: Research Funding; Kite, a Gilead Company: Research Funding; Merck: Research Funding; Genentech: Research Funding; Celgene: Research Funding; Forty Seven: Research Funding; Bristol Myers Squibb: Research Funding; Roche/Genentech: Consultancy; Autolus: Research Funding; Seagen: Consultancy, Research Funding; Pharmacyclics: Research Funding; ADC Therapeutics: Consultancy, Research Funding. Leonard: ADC Therapeutics, AstraZeneca, Bayer, BMS/Celgene, Epizyme, Inc., Genmab, Gilead/Kite, Karyopharm, BMS/Celgene, Regeneron, MEI Pharma, Miltenyi, Roche/Genentech, Sutro: Consultancy; Roche/Genentech: Consultancy. OffLabel Disclosure: venetoclax in double hit lymphoma

Abstract Background The majority of patients with relapsed/refractory (R/R) DLBCL who relapse after hematopoietic stem cell transplantation (HSCT) or chimeric antigen receptor T-cell (CAR-T) therapy, or who are not candidates for HSCT or CAR-T, have poor outcomes and need novel therapies (Crump 2017). Brentuximab vedotin (BV) was the first antibody-drug conjugate to be approved in multiple cancer types (Gauzy-Lazo 2020). The combination of a CD30-directed monoclonal antibody, a protease-cleavable linker, and the microtubule-disrupting agent monomethyl auristatin E drives the anticancer activity of BV by inducing cell cycle arrest and apoptosis (Sutherland 2006). Lenalidomide may enhance the activity of BV through immune-mediated mechanisms. In a phase 1 trial (NCT02086604) in which 37 patients with R/R DLBCL were treated with BV + lenalidomide, the objective response rate (ORR) was 56.7% (73.3% in CD30+ patients). The median duration of remission was 13.2 months in patients with a complete response (CR) or partial response (PR) and 11.7 months in patients with a CR, PR, or stable disease (SD) &gt;6 months. The median progression-free survival (PFS) and overall survival (OS) were 10.2 months and 14.3 months, respectively, and results were similar in the CD30+ and CD30 &lt;1% groups (manuscript submitted). The clinical activity and manageable safety profiles of BV, lenalidomide, and rituximab as single agents provide a strong rationale for this combination in multiple relapsed and heavily pretreated patients with R/R DLBCL. Study Design and Methods ECHELON-3 (NCT04404283) is a randomized, double-blind, placebo-controlled, active-comparator, multicenter phase 3 study designed to evaluate the efficacy of BV versus placebo, in combination with lenalidomide and rituximab, in patients with R/R DLBCL. Key eligibility criteria will include patients ≥18 years of age with R/R DLBCL with an eligible subtype, ≥2 prior lines of systemic therapy and ineligible for stem cell transplant or CAR-T therapy, Eastern Cooperative Oncology Group performance status 0 to 2, fluorodeoxyglucose-avid disease by positron emission tomography (PET), and bidimensional measurable disease of at least 1.5 cm by computed tomography (CT). Patients with a history of another malignancy within the past 2 years, any uncontrolled Grade ≥3 infection, Grade ≥2 peripheral neuropathy, or previous exposure to BV or lenalidomide will not be eligible. After completing the safety run-in period, patients (n=400) will be randomized 1:1 to receive either BV (1.2 mg/kg intravenously every 3 weeks [Q3W]) or placebo (intravenously Q3W) in combination with lenalidomide (20 mg orally daily) and rituximab (1400 mg subcutaneously Q3W from Cycle 2, with 375 mg/m 2 intravenously on Cycle 1 Day 1). Treatment may continue while there is clinical benefit (SD or better) without progression or unacceptable toxicity. Patients will be stratified by CD30 expression (≥1% [positive] vs &lt;1% [negative]), prior allogeneic or autologous stem cell transplant therapy (received or not), prior CAR-T therapy (received or not), and cell of origin (germinal center B-cell [GCB] or non-GCB). The dual primary endpoints are PFS per blinded independent central review (BICR) in the intention-to-treat (ITT) and CD30+ populations. Key secondary endpoints are OS in the ITT and CD30+ populations, and ORR per BICR. Other secondary endpoints include CR rate, duration of objective response, and safety and tolerability of the combination. Disease response will be assessed by BICR and the investigator according to the Lugano Classification Revised Staging System for nodal non-Hodgkin and Hodgkin lymphomas (Cheson 2014). Radiographic disease evaluations, including contrast-enhanced CT and PET, will be assessed at baseline, then every 6 weeks from randomization until Week 48, then every 12 weeks thereafter. PET is not required after CR is achieved For the analyses of PFS per BICR, the stratified log-rank test will be used to compare PFS between the 2 treatment groups. Hazard ratios will be estimated using the stratified Cox regression model. PFS will also be summarized using the Kaplan-Meier method. Similar methods will be used to estimate OS and other time-to-event efficacy endpoints. The study is currently enrolling and will be open in 16 countries. Disclosures Bartlett: Merck: Research Funding; Kite, a Gilead Company: Research Funding; Janssen: Research Funding; Genentech: Research Funding; Forty Seven: Research Funding; Celgene: Research Funding; Bristol Myers Squibb: Research Funding; Autolus: Research Funding; Seagen: Consultancy, Research Funding; Roche/Genentech: Consultancy; ADC Therapeutics: Consultancy, Research Funding; Millennium: Research Funding; Pharmacyclics: Research Funding. Yasenchak: Seagen Inc.: Research Funding. Harwin: Sarah Cannon Research Institute: Other: Grants, Research Funding. Sims: Seagen Inc.: Current Employment. Nowakowski: Celgene, MorphoSys, Genentech, Selvita, Debiopharm Group, Kite/Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene, NanoString Technologies, MorphoSys: Research Funding.

Abstract Introduction: Alliance for Clinical Trials in Oncology A041202 is a NCI National Clinical Trials Network phase 3 study (NCT01886872) comparing BR (Arm 1) with ibrutinib (Arm 2) and the combination of ibrutinib plus rituximab (Arm 3) to determine whether ibrutinib-containing regimens are superior to chemoimmunotherapy (CIT) in terms of progression-free survival (PFS), and whether rituximab adds benefit to ibrutinib therapy. Initial results showed that ibrutinib-containing regimens had superior PFS to CIT, and that rituximab added to ibrutinib did not improve PFS over ibrutinib alone. Pts and Methods: Eligible pts on A041202 were those age ≥ 65 years with previously untreated, symptomatic CLL. Pts had a CrCl &gt; 40 mL/min, bilirubin &lt; 1.5 x ULN, and no significant life-limiting intercurrent illness or need for warfarin treatment. Pts were stratified on Rai stage, Zap-70 methylation performed centrally, and del(17)(p13.1) or del(11)(q22.3) by local interphase cytogenetics and were randomized 1:1:1 to each arm. Pts on Arm 1 who progressed could cross over to Arm 2. Here we present an updated analysis after the third planned interim analysis of Arms 2 and 3 versus Arm 1, and at the second planned interim analysis for Arms 3 vs 2. PFS and OS were estimated using the Kaplan-Meier method and corresponding hazard ratios with p-values were estimated using Cox proportional hazards models. These data encompass patient visits through April 2020 and were locked 15 February 2021. Results: Between 12/9/2013 and 5/16/2016, 547 pts were randomized (Arms 1: 183, 2: 182, and 3: 182). Baseline characteristics have previously been reported; briefly, median age was 71 years, 53% had unmethylated Zap-70, 61% were IGHV unmutated (performed in 66% of patients), 6% had del(17p) and 20% del(11q) by central FISH. Stimulated karyotype was performed centrally and revealed ≥ 3 abnormalities in 27%, and ≥ 5 in 11% of patients. With median follow-up of 55 months (mo), median PFS was 44 mo (95% CI 38-54) in Arm 1 and has not been reached in Arms 2 or 3 [Arm 2 vs 1 hazard ratio (HR): 0.36, 95% CI 0.26-0.52, p&lt;0.0001; Arm 3 vs 1 HR 0.36, 95% CI 0.25-0.51, p&lt;0.0001; Arms 3 vs 2 HR 0.99, 95% CI 0.66-1.48, p=0.96]. 48-month PFS estimates were 47%, 76% and 76% in Arms 1, 2, and 3 respectively (Figure 1). At this time, there are no significant differences in overall survival (OS) among arms (p=0.49). 48-month OS estimates were 84%, 85%, and 86% in Arms 1, 2, and 3, respectively (Figure 2). The benefit of ibrutinib regimens over CIT, with no additional benefit of rituximab when combined with ibrutinib, was consistent for all subgroups of patients defined by TP53 abnormalities, del(11q), complex karyotype, and IGHV (Figure 3). No significant interaction effects were observed between treatment arm and del(11q), complex karyotype, or IGHV. However, greater benefit of ibrutinib regimens over CIT was observed among patients with TP53 abnormalities than without (p&lt;0.001). Thus in Arm 1, PFS was significantly worse for those with TP53 abnormalities vs without (HR 5.32, 95% CI 3.05-9.27, p&lt;0.0001), but in Arms 2 and 3 combined, there was no significant difference in PFS by presence/absence of TP53 abnormalities (HR 0.99, 95% CI 0.51-1.91, p=0.98). Notable adverse events with ibrutinib include atrial fibrillation or flutter (afib) and hypertension (HTN). All grade afib was seen in 11 pts on BR (6%) and 67 pts on ibrutinib (19%). All grade HTN was seen in 95 pts on BR (54%) and 263 pts on ibrutinib (73%). Conclusions: This update of the A041202 trial continues to show that ibrutinib regimens prolong PFS over BR for older patients with treatment-naïve CLL. With longer follow-up, these benefits continue to be seen across subgroups, including those associated with higher risk disease. Strikingly, within the ibrutinib arms, there does not appear to be inferior PFS for patients with abnormalities in TP53, the highest risk feature seen in CLL, and a predictor of inferior PFS with ibrutinib in relapsed CLL. This differentiates ibrutinib (and perhaps BTKi in general) from other targeted therapy paradigms for treatment-naïve CLL. Similar to prior studies, rates of afib and HTN continue to increase with time on therapy. These data support the use of ibrutinib as initial therapy in CLL, and strengthen the rationale for use of ibrutinib for high risk disease. Support: U10CA180821, U10CA180882, U24CA196171, https://acknowledgments.alliancefound.org, Pharmacyclics, Inc Figure 1 Figure 1. Disclosures Woyach: Gilead Sciences Inc: Other: Data & Safety; AbbVie Inc, ArQule Inc, Janssen Biotech Inc, AstraZeneca, Beigene: Other: Advisory Committee; AbbVie Inc, Loxo Oncology Inc, a wholly owned subsidiary of Eli Lilly & Company: Research Funding; AbbVie Inc, ArQule Inc, AstraZeneca Pharmaceuticals LP, Janssen Biotech Inc, Pharmacyclics LLC, an AbbVie Company,: Consultancy. Ruppert: Telios Pharma: Consultancy. Ding: Merck: Membership on an entity's Board of Directors or advisory committees, Research Funding; DTRM: Research Funding; Octapharma: Membership on an entity's Board of Directors or advisory committees. Bartlett: ADC Therapeutics: Consultancy, Research Funding; Roche/Genentech: Consultancy; Seagen: Consultancy, Research Funding; Autolus: Research Funding; Bristol Myers Squibb: Research Funding; Celgene: Research Funding; Forty Seven: Research Funding; Genentech: Research Funding; Janssen: Research Funding; Kite, a Gilead Company: Research Funding; Merck: Research Funding; Millennium: Research Funding; Pharmacyclics: Research Funding. Brander: Pfizer: Consultancy, Other: Biosimilars outcomes research panel; Genentech: Consultancy, Research Funding; Verastem: Consultancy; Juno Therapeutics/Celgene/Bristol Myers Squibb: Research Funding; LOXO: Research Funding; TG Therapeutics: Consultancy, Research Funding; MEI Pharma: Research Funding; NCCN: Other: panel member; ArQule/Merck: Consultancy; Pharmacyclics LLC, an AbbVie Company: Consultancy, Research Funding; DTRM: Research Funding; BeiGene: Research Funding; AstraZeneca: Research Funding; Ascentage: Research Funding; ArQule: Research Funding; AbbVie: Consultancy, Other: informCLL registry steering committee, Research Funding; Novartis: Research Funding. Barr: Seattle Genetics: Consultancy; Bristol Meyers Squibb: Consultancy; AstraZeneca: Consultancy; Beigene: Consultancy; Genentech: Consultancy; Abbvie/Pharmacyclics: Consultancy; Gilead: Consultancy; Morphosys: Consultancy; TG Therapeutics: Consultancy; Janssen: Consultancy. Rogers: Pharmacyclics LLC: Consultancy; Innate Pharma: Consultancy; Genentech: Consultancy, Research Funding; AstraZeneca: Consultancy; Acerta Pharma: Consultancy; AbbVie Inc.: Consultancy, Research Funding; Janssen Pharmaceuticals, Inc: Research Funding; ovartis Pharmaceuticals Corporation: Research Funding. Parikh: Pharmacyclics, MorphoSys, Janssen, AstraZeneca, TG Therapeutics, Bristol Myers Squibb, Merck, AbbVie, and Ascentage Pharma: Research Funding; Pharmacyclics, AstraZeneca, Genentech, Gilead, GlaxoSmithKline, Verastem Oncology, and AbbVie: Membership on an entity's Board of Directors or advisory committees. Coutre: Acerta: Other: Data Safety Monitoring Committee, Research Funding; Genentech: Consultancy, Membership on an entity's Board of Directors or advisory committees; Beigene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Data Safety Monitoring Committee, Research Funding; AstraZeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmacyclics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Larson: Epizyme: Consultancy; Astellas: Consultancy, Research Funding; Gilead: Research Funding; CVS/Caremark: Consultancy; Takeda: Research Funding; Novartis: Research Funding; Rafael Pharmaceuticals: Research Funding; Cellectis: Research Funding. Erba: AbbVie Inc: Other: Independent review committee; AbbVie Inc; Agios Pharmaceuticals Inc; ALX Oncology; Amgen Inc; Daiichi Sankyo Inc; FORMA Therapeutics; Forty Seven Inc; Gilead Sciences Inc; GlycoMimetics Inc; ImmunoGen Inc; Jazz Pharmaceuticals Inc; MacroGenics Inc; Novartis; PTC Therapeutics: Research Funding; AbbVie Inc; Agios Pharmaceuticals Inc; Bristol Myers Squibb; Celgene, a Bristol Myers Squibb company; Incyte Corporation; Jazz Pharmaceuticals Inc; Novartis: Speakers Bureau; AbbVie Inc; Agios Pharmaceuticals Inc; Astellas; Bristol Myers Squibb; Celgene, a Bristol Myers Squibb company; Daiichi Sankyo Inc; Genentech, a member of the Roche Group; GlycoMimetics Inc; Incyte Corporation; Jazz Pharmaceuticals Inc; Kura Oncology; Nov: Other: Advisory Committee. Litzow: Jazz: Other: Advisory Board; Pluristem: Research Funding; Actinium: Research Funding; Amgen: Research Funding; Astellas: Research Funding; AbbVie: Research Funding; Omeros: Other: Advisory Board; Biosight: Other: Data monitoring committee. Blachly: INNATE: Consultancy, Honoraria; KITE: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria; AstraZeneca: Consultancy, Honoraria. Owen: Genentech: Research Funding; Gilead: Honoraria; Janssen: Honoraria, Research Funding; AstraZeneca: Honoraria, Research Funding; AbbVie: Honoraria, Research Funding; Roche: Honoraria, Research Funding; Merck: Honoraria; Servier: Honoraria; Incyte: Honoraria; Pharmacyclics: Research Funding. Abramson: Bristol-Myers Squibb Company: Consultancy, Research Funding; C4 Therapeutics: Consultancy; Morphosys: Consultancy; Kite Pharma: Consultancy; Novartis: Consultancy; EMD Serono: Consultancy; Genmab: Consultancy; Bluebird Bio: Consultancy; Kymera: Consultancy; BeiGene: Consultancy; Incyte Corporation: Consultancy; Astra-Zeneca: Consultancy; Allogene Therapeutics: Consultancy; Seagen Inc.: Research Funding; AbbVie: Consultancy; Karyopharm: Consultancy; Genentech: Consultancy. Brown: Abbvie, Acerta/Astra-Zeneca, Beigene, Bristol-Myers Squibb/Juno/Celgene, Catapult, Eli Lilly, Genentech/Roche, Janssen, MEI Pharma, Morphosys AG, Nextcea, Novartis, Pfizer, Rigel: Consultancy; Invectys: Other: Data Safety Monitoring Committee Service; Gilead, Loxo/Lilly, SecuraBio, Sun, TG Therapeutics: Research Funding. Stone: Onconova: Consultancy; Syntrix/ACI: Membership on an entity's Board of Directors or advisory committees; Syndax: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Research Funding; Elevate Bio: Membership on an entity's Board of Directors or advisory committees; Boston Pharmaceuticals: Consultancy; Bristol Myers Squibb: Consultancy; Jazz: Consultancy; Arog: Consultancy, Research Funding; Gemoab: Membership on an entity's Board of Directors or advisory committees; GlaxoSmithKline: Consultancy; Janssen: Consultancy; Innate: Consultancy; BerGen Bio: Membership on an entity's Board of Directors or advisory committees; Astellas: Membership on an entity's Board of Directors or advisory committees; Foghorn Therapeutics: Consultancy; AbbVie: Consultancy; Actinium: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Aprea: Consultancy; Syros: Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy; Agios: Consultancy, Research Funding; Celgene: Consultancy; Macrogenics: Consultancy. Byrd: Novartis, Trillium, Astellas, AstraZeneca, Pharmacyclics, Syndax: Consultancy, Honoraria; Vincerx Pharmaceuticals: Current equity holder in publicly-traded company, Membership on an entity's Board of Directors or advisory committees; Newave: Membership on an entity's Board of Directors or advisory committees.