Koehler, Amber B.

SummaryPatients with chronic lymphocytic leukaemia (CLL) disease progression on ibrutinib or after sequential ibrutinib and venetoclax‐based treatments (double‐refractory) have poor outcomes. In this retrospective study, we analysed outcomes with combined ibrutinib and venetoclax treatment in these groups of patients. The median treatment‐free and overall survival for 22 patients with prior progression on ibrutinib (venetoclax‐naïve) were 23.7 and 47.1 months respectively. In 11 patients with double‐refractory CLL, the median treatment‐free and overall survival were 11.2 and 27.0 months respectively. The combination of ibrutinib and venetoclax may help bridge the current gap in options for patients with disease refractory to the most commonly used novel agents.

Abstract INTRODUCTION Sparse data exist regarding I+V in an off-trial setting, particularly in patients (pts) with progression of disease on either I or V as single agent treatment. The 1-year overall survival (OS) rates with V monotherapy following I range from 75%-91% (Eyre et al, BJH 2019; Jones et al, Lancet Oncol 2018); however, longer-term follow-up of these or other patient cohorts treated with V after I has not yet been reported. Effective options in double-refractory pts are lacking when a clinical trial is not feasible. Here, we report our experience with I+V in these patient groups. METHODS After IRB approval, we reviewed the records of pts seen at Mayo Clinic (between 4/2012-1/2021) who received I+V therapy off-trial for CLL progression. Pts treated with I+V for Richter's transformation were excluded. Time to next treatment (TTNT) was measured from I+V treatment start date to the date of next treatment start or last known treatment status with death as a competing risk. OS was measured from I+V start date until date of death or when the patient was last known alive; OS was analyzed using the Kaplan-Meier method and Cox proportional hazards model. RESULTS Thirty-three pts with progressive CLL were treated with I+V (median duration 13.3 months [95% CI: 7.1 months-not estimable (NE)]). The median age was 70 years (range 47-86), 6 (18%) were women, and 20 (65%) had del(17p) or TP53 mutation. The median number of prior lines of therapy was 3 (range 1-15). Additional characteristics at the time of I+V start are shown in Table 1. Median follow-up from start of I+V was 23.8 months. Among 22 pts with prior progression on I only (V-naïve), the median duration of I+V was 14.8 months (95% CI 7.6 months-NE). The median duration on either I or V from the start of combination was 20.3 months (95% CI 8.3 months-NE). The median TTNT was 25.1 months (Figure 1A). Four pts proceeded to cellular therapy (alloSCT [n=3], CAR-T [n=1]) while on I+V. Next therapy (n=9) consisted of Richter transformation treatment (n=2), chemotherapy plus continued I+V (n=1), anti-CD20 plus continued I+V (n=1), duvelisib + I (n=1), TP-0903 + I (n=1), reintroduction of I at disease progression after previously stopping I during I+V therapy (n=1), and reintroduction of I (n=1) or V (n=1) at disease progression after previously stopping I+V. Of 9 pts who did not receive subsequent therapy, 4 pts remain on I+V (median duration 16.4 months), 4 pts continued V after discontinuing I (median duration on V from start of I+V was 21.5 months), and 1 pt discontinued I+V following a second cancer diagnosis and died without receiving additional CLL-directed treatment. Eleven pts received I+V in the double-refractory setting; 9 pts had prior disease progression on sequential I then V and 2 pts had prior disease progression on sequential V then I. The median duration of I+V was 7.5 months (95% CI 4.3 months-NE), and the median duration of either agent from I+V start was 10.8 months (95% CI 7.1 months-NE). The median TTNT was 14.0 months (Figure 1A). Eight pts required additional treatment, consisting of PI3K inhibitor (n=2), anti-CD20 added to I+V (n=1), CAR-T (n=1), anti-CD20 with (n=1) or without (n=1) bendamustine added to continued I, and Richter transformation treatment (n=2). One pt continues I+V (17.4 months ongoing) without further treatment. Two pts died from disease progression without receiving additional treatment. The median OS of all 33 pts was 27.4 months (95% CI 25.9 months-NE; Figure 1B). The median OS of the 22 pts with prior progression on I (V-naïve) was 47.1 months (95% CI 27.7 months-NE), and the median OS of the 11 pts with prior progression on I and V separately was 27.0 months (95% CI 15.5 months-NE). In univariate analyses, prior progression on V was a predictor of shorter OS (HR=3.9; 95% CI 1.4-11.2; p=0.01). CONCLUSIONS Combination I+V therapy in heavily pre-treated CLL pts who have disease progression after I provides durable benefit with a median OS approaching 4 years. In the double-refractory setting, repurposing both drugs as combination I+V therapy can be a useful strategy, despite the short-term disease control, for pts where clinical trial options are limited or not available. Further examination of these approaches in larger cohorts and understanding the operative resistance mechanisms in pts with double-refractory disease are key next studies. Figure 1 Figure 1. Disclosures Ding: Octapharma: Membership on an entity's Board of Directors or advisory committees; DTRM: Research Funding; Merck: Membership on an entity's Board of Directors or advisory committees, Research Funding. Chanan-Khan: BeiGene, Jansen, Ascentage: Honoraria; Ascentage, Starton, Cellectar, NonoDev, Alpha2 Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Alpha2 Pharmaceuticals: Patents & Royalties: Tabi; Ascentage: Research Funding; Cellectar: Current equity holder in publicly-traded company; Alpha2 Pharmaceuticals, NonoDev, Starton: Current holder of stock options in a privately-held company; BieGene, Jansen, Ascentage: Consultancy. Kenderian: Humanigen, Inc.: Consultancy, Honoraria, Research Funding. Wang: TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; MorphoSys: Research Funding; Novartis: Research Funding; LOXO Oncology: Membership on an entity's Board of Directors or advisory committees, Research Funding; Genentech: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; InnoCare: Research Funding; Eli Lilly: Membership on an entity's Board of Directors or advisory committees. Ailawadhi: Pharmacyclics: Consultancy, Research Funding; Xencor: Research Funding; Janssen: Consultancy, Research Funding; Cellectar: Research Funding; Sanofi: Consultancy; BMS: Consultancy, Research Funding; GSK: Consultancy, Research Funding; Ascentage: Research Funding; Medimmune: Research Funding; Karyopharm: Consultancy; Amgen: Consultancy, Research Funding; Beigene: Consultancy; AbbVie: Consultancy; Takeda: Consultancy; Genentech: Consultancy. Koehler: AbbVie: Membership on an entity's Board of Directors or advisory committees; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees. Kay: AstraZeneca: Membership on an entity's Board of Directors or advisory committees; Dava Oncology: Membership on an entity's Board of Directors or advisory committees; Targeted Oncology: Membership on an entity's Board of Directors or advisory committees; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Juno Therapeutics: Membership on an entity's Board of Directors or advisory committees; Genentech: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol Meyer Squib: Membership on an entity's Board of Directors or advisory committees, Research Funding; TG Therapeutics: Research Funding; Agios Pharm: Membership on an entity's Board of Directors or advisory committees; Sunesis: Research Funding; Rigel: Membership on an entity's Board of Directors or advisory committees; Acerta Pharma: Research Funding; CytomX Therapeutics: Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Morpho-sys: Membership on an entity's Board of Directors or advisory committees; Oncotracker: Membership on an entity's Board of Directors or advisory committees; MEI Pharma: Research Funding; Behring: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Tolero Pharmaceuticals: 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. OffLabel Disclosure: Combination ibrutinib and venetoclax in patients with relapsed CLL.

AbstractMonoclonal B‐cell lymphocytosis (MBL) and chronic lymphocytic leukemia (CLL) are clonal B‐cell disorders associated with an increased risk of infections and impaired vaccination responses. We investigated the immunogenicity of recombinant zoster vaccine (RZV) in these patients. Individuals with MBL/untreated CLL and Bruton tyrosine kinase inhibitor (BTKi)‐treated CLL patients were given two doses of RZV separated by 2 months. Responses assessed at 3 and 12 months from the first dose of RZV by an anti‐glycoprotein E ELISA antibody assay and by dual‐color Interferon‐γ and Interleukin‐2FLUOROSPOT assays were compared to historic controls matched by age and sex. About 62 patients (37 MBL/untreated CLL and 25 BTKi‐treated CLL) were enrolled with a median age of 68 years at vaccination. An antibody response at 3 months was seen in 45% of participants, which was significantly lower compared to historic controls (63%, p = .03). The antibody response did not significantly differ between MBL/untreated CLL and BTKi‐treated CLL (51% vs. 36%, respectively, p = .23). The CD4+ T‐cell response to vaccination was significantly lower in study participants compared to controls (54% vs. 96%, p < .001), mainly due to lower responses among BTKi‐treated patients compared to untreated MBL/CLL (32% vs. 73%, p = .008). Overall, only 29% of participants achieved combined antibody and cellular responses to RZV. Among participants with response assessment at 12 months (n = 47), 24% had antibody titers below the response threshold. Hypogammaglobulinemia and BTKi therapy were associated with reduced T‐cell responses in a univariate analysis. Strategies to improve vaccine response to RZV among MBL/CLL patients are needed.

Abstract The utility of the chronic lymphocytic leukemia-international prognostic index (CLL-IPI) in predicting outcomes of individuals with Rai 0 stage CLL and monoclonal B-cell lymphocytosis (MBL) is unclear. We identified 969 individuals (415 MBL and 554 Rai 0 CLL; median age, 64 years; 65% men) seen at Mayo Clinic between 1 January 2001 and 1 October 2018, and ascertained time to first therapy (TTFT) and overall survival (OS). After a median follow up of 7 years, the risk of disease progression needing therapy was 2.9%/y for MBL (median, not reached) and 5%/y for Rai 0 CLL (median, 10.4 years). Among patients with low, intermediate, and high/very high-risk CLL-IPI risk groups, the estimated 5-year risk of TTFT was 13.5%, 30%, and 58%, respectively, P&lt; .0001 (c-statistic = 0.69); and the estimated 5-year OS was 96.3%, 91.5%, and 76%, respectively, P&lt; .0001 (c-statistic = 0.65). In a multivariable analysis of absolute B-cell count with individual factors of the CLL-IPI, the absolute B-cell count was associated with shorter TTFT (hazard ratio [HR] for each 10 × 109/L increase: 1.31; P&lt; .0001) and shorter OS (HR: 1.1; P = .02). The OS of the entire cohort was similar to that of the age- and sex-matched general population of Minnesota (P = .17), although Rai 0 CLL patients with high and very high-risk CLL-IPI score had significantly shorter OS (P= .01 and P= .0001, respectively). The results of this study demonstrate the ability of CLL-IPI to predict time from diagnosis to first treatment (an end point not affected by therapy) in a large cohort of patients whose only manifestation of disease is a circulating clonal lymphocyte population.

Introduction: Richter transformation (RT) refers to transformation of chronic lymphocytic leukemia (CLL) to diffuse large B-cell lymphoma (DLBCL) or other aggressive lymphomas. The incidence, clinical characteristics, and outcomes of RT with CNS involvement remain undefined. Methods: Biopsy-confirmed RT diagnosed from 4/1993 to 4/2018 was identified from the Mayo Clinic CLL database. RT cases with CNS involvement were further reviewed, with clinical characteristics, treatment and follow-up data abstracted. Overall survival (OS) was defined as time from CNS involvement to death from any cause and analyzed using the Kaplan-Meier method. Results: Among 204 CLL patients with biopsy-proven RT, 15 patients had documented CNS involvement by imaging (parenchymal n=11, ocular n=1, parenchymal and ocular n=1, leptomeningeal n=1, cranial and spinal nerve roots n=1). Biopsy confirmation of CNS involvement was available in 11 patients. Of these 15 patients, 10 had CNS involvement at initial RT diagnosis, and 5 patients developed CNS involvement at RT progression, with a median time from RT diagnosis to CNS involvement of 14.9 months (range 2.8-41.1). Prior to RT, 11 patients (73.3%) received no treatment for CLL, 3 (53.4%) received chemoimmunotherapy (CIT) only (1-3 lines), and 1 patient (6.7%) received CIT (1 line) and ibrutinib. CLL FISH results were available in 9 patients, with del(17p) in 2, trisomy 12 in 2, del(13q) in 3, and normal results in 2. One patient had TP53 mutation (FISH result unavailable). IgHV mutation status was known in 3 patients and 1 was unmutated. The median time to RT was 4.4 years (range 0-11.4). The median age at RT diagnosis was 70 years (range 59-78), and 9 (60%) were male. The histology of RT was DLBCL in all 15 patients (diagnosed by CNS biopsy in 8 and other biopsies in 7), with GCB subtype in 6 and non-GCB subtype in 3. MYC rearrangement was detected in 4 of 6 patients tested, and 2 of those also had BCL-2 rearrangement (MYC/BCL-2 double hit). Of the 10 patients with CNS involvement at initial RT diagnosis, 4 had isolated CNS involvement (confirmed by brain biopsy [n=2] or vitreous biopsy [n=2]). All 4 patients were treated with high dose (HD) methotrexate (MTX) based regimen, and 3 patients achieved complete remission (CR) and underwent autologous stem cell transplant with continued CR, while 1 patient achieved partial remission and received whole brain radiotherapy (WBRT) at disease progression. Six patients had both systemic and CNS involvement (confirmed by brain biopsy [n=2] or CSF examination [n=2] in 4; the other 2 were diagnosed by imaging). All 6 patients received CNS directed therapy (HD MTX [n=5] or WBRT [n=1]) as well as systemic therapy (R-CHOP [n=5] or HyperCVAD [n=1]), with varied short duration of disease control (Figure 1A). Of the 5 patients who developed CNS involvement at RT progression (after 1-2 lines of therapy including first-line R-CHOP), 2 had isolated CNS involvement (1 was confirmed by CSF examination and the other was by imaging only). Both were treated with HD MTX based regimen, and 1 achieved a durable remission of 2 years but eventually had CNS relapse, while the other had no response and received WBRT with limited benefit. Three patients had both systemic and CNS involvement (2 were confirmed by CSF examination and the other was by imaging only), and all 3 patients were treated with HD MTX based regimen but all had CNS disease progression within 3 months (Figure 1A). The OS after CNS involvement for all 15 RT patients was 9.4 months (95% CI 2.3-19.1). Patients with CNS involvement at initial RT diagnosis had numerically longer OS compared to patients who developed CNS involvement at RT progression (median OS 13.0 vs 4.1 months, P = 0.137; Figure 1B). Patients with isolated CNS involvement had better OS compared to patients with both CNS and systemic involvement (median OS 32.0 vs 5.3 months, P = 0.009; Figure 1C). Three of the 4 patients who only had isolated CNS involvement at the time of RT diagnosis have ongoing long term remission and survival (Figure 1A). Conclusions: In this large series of RT, approximately 1 in 14 patients had CNS involvement. Patients with isolated CNS involvement appeared to have favorable long term outcome; however, RT patients with both systemic and CNS involvement had extremely poor survival. The incidence, molecular characteristics, and optimal management of RT with CNS involvement in the novel agent era warrant future multicenter studies. Disclosures Wang: Incyte: Research Funding; Innocare: Research Funding; Novartis: Research Funding. Parikh:GlaxoSmithKline: Honoraria; Pharmacyclics: Honoraria, Research Funding; AstraZeneca: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; MorphoSys: Research Funding; TG Therapeutics: Research Funding; Merck: Research Funding; AbbVie: Honoraria, Research Funding; Ascentage Pharma: Research Funding; Genentech: Honoraria; Verastem Oncology: Honoraria. Kay:Tolero Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol Meyer Squib: Membership on an entity's Board of Directors or advisory committees, Research Funding; Acerta Pharma: Research Funding; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Research Funding; MEI Pharma: Research Funding; Sunesis: Research Funding; Astra Zeneca: Membership on an entity's Board of Directors or advisory committees; Agios Pharma: Membership on an entity's Board of Directors or advisory committees; Cytomx: Membership on an entity's Board of Directors or advisory committees; Morpho-sys: Membership on an entity's Board of Directors or advisory committees; Rigel: Membership on an entity's Board of Directors or advisory committees; Oncotracker: Membership on an entity's Board of Directors or advisory committees; Dava Oncology: Membership on an entity's Board of Directors or advisory committees; Juno Theraputics: Membership on an entity's Board of Directors or advisory committees. Witzig:AbbVie: Consultancy; MorphSys: Consultancy; Immune Design: Research Funding; Karyopharm Therapeutics: Research Funding; Incyte: Consultancy; Spectrum: Consultancy; Celgene: Consultancy, Research Funding; Acerta: Research Funding. Nowakowski:MorphoSys: Consultancy, Research Funding; Roche: Consultancy, Research Funding; Celgene/BMS: Consultancy, Research Funding; Kite: Consultancy; Denovo: Consultancy; Kymera: Consultancy; Ryvu: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other; Curis: Consultancy; Seattle Genetics: Consultancy; Nanostrings: Research Funding. Ansell:Trillium: Research Funding; AI Therapeutics: Research Funding; Affimed: Research Funding; Regeneron: Research Funding; Takeda: Research Funding; ADC Therapeutics: Research Funding; Seattle Genetics: Research Funding; Bristol Myers Squibb: Research Funding. Kenderian:MorphoSys: Research Funding; Sunesis: Research Funding; Tolero: Research Funding; BMS: Research Funding; Juno: Research Funding; Gilead: Research Funding; Kite: Research Funding; Novartis: Patents & Royalties, Research Funding; Torque: Consultancy; Humanigen: Consultancy, Patents & Royalties, Research Funding; Lentigen: Research Funding; Mettaforge: Patents & Royalties. Ding:DTRM: Research Funding; Merck: Membership on an entity's Board of Directors or advisory committees, Research Funding; Beigene: Membership on an entity's Board of Directors or advisory committees; alexion: Membership on an entity's Board of Directors or advisory committees; MEI Pharma: Membership on an entity's Board of Directors or advisory committees; Octapharma: Membership on an entity's Board of Directors or advisory committees; Astra Zeneca: Research Funding; Abbvie: Research Funding.

Introduction: In 2017, a two-dose recombinant zoster vaccine (RZV) containing glycoprotein E (gE) and a novel adjuvant was approved to prevent herpes zoster and its complications in adults ≥50 years of age in the US. There are limited data on the immunogenicity and safety of RZV in patients with chronic lymphocytic leukemia (CLL). Methods: Between 8/15/2018 and 11/4/2019, RZV-naïve patients with CLL and monoclonal B-cell lymphocytosis (MBL) seen at Mayo Clinic, Rochester, MN were enrolled in this IRB-approved study. All participants received two doses of vaccine, at 0 and 2 months after enrollment. Cell-mediated immunity was measured by dual-color interferon γ (IFN- γ) and interleukin 2 (IL-2) FLUOROSpot in peripheral blood mononuclear cells (PBMC) after depletion of ≥50% leukemic B cells. Results were reported in spot forming cells (SFC)/106 PBMC in wells stimulated with gE overlapping peptides or varicella zoster virus (VZV) inactivated cell lysate. Response rate was defined as the proportion of participants who achieved a ≥2-fold increase in IFN- γ or IL-2 SFC/106 PBMC one month after the second dose of vaccine compared with pre-vaccination baseline levels. We also determined the geometric mean fold rise (GMFR) and geometric mean count (GMC) of SFC /106 PBMC at baseline and 90 days after the first dose of vaccine. Two cohorts were enrolled: Cohort 1 consisted of individuals with previously untreated MBL and CLL; and Cohort 2 consisted of CLL participants who were on Bruton tyrosine kinase inhibitor (BTKi) therapy. We compared the response data to historic age-and sex-matched healthy controls who received RZV. Chi-square or Fisher's exact tests measured differences in response rates and Kruskall-Wallis tested for differences in continuous variables. Among CLL participants, multivariable regression analysis was used to investigate the association between day 90 SFC and prior BTKi treatment, accounting for age at RZV, age at CLL diagnosis, sex, and day 0 SFC. Results: Sixty-one participants were enrolled. Paired samples were available for 41 participants (22 in Cohort 1 and 19 [18 ibrutinib and 1 acalabrutinib] in Cohort 2), and 68 age- and sex-matched healthy controls. Baseline characteristics of MBL/CLL participants are shown in Table 1. Compared to healthy controls, participants with MBL/CLL had a significantly lower IFN-γ VZV-specific response rate (41% vs. 63%, p=0.03) and IFN-γ gE-specific response (56% vs. 96%, p&lt;0.001); although there were no differences in IL-2 response rates to VZV (51% vs 68%, p=0.09) or gE (95% vs. 100%, p=0.14, Table 2). There were differences in GMFR between participants with MBL/CLL and controls that reached statistical significance for IFN-γ and IL-2 gE-specific responses and borderline significance for IFN-γ VZV-specific responses (Table 2). VZV-specific response rates did not significantly differ between individuals with untreated MBL/CLL and those receiving BTKi (52% vs. 28%, p=0.12 for IFN- γ; (62% vs. 39%, p=0.15 for IL-2), nor did IL-2 gE-specific responses (96% vs. 95%, p=1.0). However, untreated MBL/CLL participants had significantly higher IFN- γ gE-specific response rate compared to BTKi-treated individuals (73% vs. 37%, p=0.02, Table 2). IFN- γ and IL-2 VZV- and gE-specific SFC GMC was significantly higher at Day 90 compared to Day 0 in all vaccinees, although the magnitude of response was significantly lower in MBL/CLL participants compared to healthy controls (Table 3). Among participants with MBL/CLL, age at diagnosis, age at receipt of RZV, and sex did not predict response to vaccination after accounting for prevaccination values. No serious adverse events were noted among MBL/CLL participants while on this study. Additional analyses including determination of humoral immunogenicity and long-term follow up to ascertain risk of herpes zoster infection are ongoing at this time. Conclusion: RZV was associated with lower cell mediated immunogenicity in MBL/CLL participants compared to healthy older adults. Among individuals with CLL, BTKi treatment was associated with decreased cell mediated immunogenicity of the vaccine. Given the inferior response rates, an additional dose of RZV may be considered to boost responses and should be studied in this patient population. Disclosures Johnson: GSK: Research Funding. Ding:Abbvie: Research Funding; Astra Zeneca: Research Funding; DTRM: Research Funding; alexion: Membership on an entity's Board of Directors or advisory committees; MEI Pharma: Membership on an entity's Board of Directors or advisory committees; Octapharma: Membership on an entity's Board of Directors or advisory committees; Merck: Membership on an entity's Board of Directors or advisory committees, Research Funding; Beigene: Membership on an entity's Board of Directors or advisory committees. Kenderian:Humanigen: Consultancy, Patents & Royalties, Research Funding; Torque: Consultancy; Novartis: Patents & Royalties, Research Funding; Kite: Research Funding; Gilead: Research Funding; Juno: Research Funding; BMS: Research Funding; Tolero: Research Funding; Mettaforge: Patents & Royalties; Lentigen: Research Funding; MorphoSys: Research Funding; Sunesis: Research Funding. Wang:Novartis: Research Funding; Incyte: Research Funding; Innocare: Research Funding. Kay:Juno Theraputics: Membership on an entity's Board of Directors or advisory committees; Oncotracker: Membership on an entity's Board of Directors or advisory committees; Dava Oncology: Membership on an entity's Board of Directors or advisory committees; Rigel: Membership on an entity's Board of Directors or advisory committees; Morpho-sys: Membership on an entity's Board of Directors or advisory committees; Cytomx: Membership on an entity's Board of Directors or advisory committees; Agios Pharma: Membership on an entity's Board of Directors or advisory committees; Astra Zeneca: Membership on an entity's Board of Directors or advisory committees; Sunesis: Research Funding; Abbvie: Research Funding; MEI Pharma: Research Funding; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Acerta Pharma: Research Funding; Tolero Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol Meyer Squib: Membership on an entity's Board of Directors or advisory committees, Research Funding. Levin:GSK: Research Funding. Kennedy:ICW Ventures: Research Funding. Weinberg:GSK: Research Funding. Parikh:GlaxoSmithKline: Honoraria; AstraZeneca: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; TG Therapeutics: Research Funding; Merck: Research Funding; AbbVie: Honoraria, Research Funding; MorphoSys: Research Funding; Verastem Oncology: Honoraria; Pharmacyclics: Honoraria, Research Funding; Genentech: Honoraria; Ascentage Pharma: Research Funding.

Background: Clinical factors including previous history of AF, heart failure, hypertension, valvular heart disease, increased age and male gender increase the risk of AF in CLL patients (Shanafelt, Leukemia and Lymphoma 2017). Treatment with Bruton tyrosine kinase inhibitors (BTKi) such as ibrutinib has also been associated with an increased risk of AF in CLL. We evaluated the role of artificial intelligence electrocardiography (AI-ECG) in predicting ibrutinib-induced AF (and, for reference, AF unrelated to ibrutinib) in patients with CLL. Methods: We identified two cohorts of CLL patients using the Mayo Clinic CLL Database. Cohort 1 included patients evaluated within 12 months of CLL diagnosis who did not ever receive ibrutinib. Cohort 2 included patients who were treated with ibrutinib. The electrocardiographic signature of AF in sinus rhythm was detected by an AI-ECG algorithm previously developed using a convolutional neural network (Attia, Lancet 2019). The baseline AI-ECG AF score (positive defined as &gt;0.10 on a scale of 0-1 which offers best balance between sensitivity and specificity per Attia et al.) was computed based on ECGs obtained within 10 years prior to CLL diagnosis (Cohort 1) or 10 years prior to initiation of ibrutinib therapy (Cohort 2). Patients with AF at baseline, missing data, or with ECGs previously used to train the AI algorithm were excluded. Reverse Kaplan Meier diagrams were plotted for both cohorts grouped by AI-ECG positivity. Cox proportional hazards were fitted to assess the predictive ability of AI-ECG in both cohorts. Results: After screening 2,739 patients and applying exclusion criteria (126 patients had baseline AF) a total of 1,149 patients with median 4 (interquartile range [IQR] 2-9) baseline ECGs were included in the analysis (Figure 1A). Cohort 1 included 951 patients with a median follow up of 3.0 (IQR 0.6-7.0) years and positive baseline AI-ECG in 546 (57%) patients. Cohort 2 included 198 patients with a median follow up of 1.6 (IQR 0.7-3.2) years and positive baseline AI-ECG in 91 (46%) patients. In Cohort 1, the median age was 67 years (IQR 58-72), 681 (72%) of patients were men, 68% had low/intermediate risk CLL-International Prognostic Index (IPI), and 32% had high/very high-risk CLL-IPI. In Cohort 2, the median age was 69 years (IQR 62-75), 139 (70%) of patients were men, 13% had low/intermediate risk CLL-IPI, and 87% had high/very high-risk CLL-IPI. AF occurred during follow up in 164 patients (17%) in Cohort 1 and 46 patients (23%) in Cohort 2. In both Cohorts 1 and 2, a positive baseline AI-ECG significantly increased the incidence of AF during follow up (log rank &lt;0.001) (Figure 1B and C). Hazard ratios (for positive vs. negative AI-ECG) were 33.9 (95% confidence interval [CI] 15.0-76.6) for Cohort 1 and 14.8 (95% CI 5.3-41.3) for Cohort 2. Conclusion: The addition of AI to a standard 12-lead ECG obtained during normal sinus rhythm - an inexpensive and ubiquitous test - predicts the occurrence of future AF in patients with CLL. This holds true irrespective of BTKi -based therapy and has important implications for the management of CLL patients. Disclosures Ding: Merck: Membership on an entity's Board of Directors or advisory committees, Research Funding; DTRM: Research Funding; Astra Zeneca: Research Funding; Abbvie: Research Funding; Octapharma: Membership on an entity's Board of Directors or advisory committees; MEI Pharma: Membership on an entity's Board of Directors or advisory committees; alexion: Membership on an entity's Board of Directors or advisory committees; Beigene: Membership on an entity's Board of Directors or advisory committees. Kenderian:BMS: Research Funding; Gilead: Research Funding; Novartis: Patents & Royalties, Research Funding; Mettaforge: Patents & Royalties; Juno: Research Funding; MorphoSys: Research Funding; Lentigen: Research Funding; Sunesis: Research Funding; Tolero: Research Funding; Kite: Research Funding; Humanigen: Consultancy, Patents & Royalties, Research Funding; Torque: Consultancy. Wang:Novartis: Research Funding; Innocare: Research Funding; Incyte: Research Funding. Kay:Juno Theraputics: Membership on an entity's Board of Directors or advisory committees; Oncotracker: Membership on an entity's Board of Directors or advisory committees; Dava Oncology: Membership on an entity's Board of Directors or advisory committees; Rigel: Membership on an entity's Board of Directors or advisory committees; Morpho-sys: Membership on an entity's Board of Directors or advisory committees; Cytomx: Membership on an entity's Board of Directors or advisory committees; Agios Pharma: Membership on an entity's Board of Directors or advisory committees; Astra Zeneca: Membership on an entity's Board of Directors or advisory committees; Sunesis: Research Funding; Abbvie: Research Funding; MEI Pharma: Research Funding; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Acerta Pharma: Research Funding; Bristol Meyer Squib: Membership on an entity's Board of Directors or advisory committees, Research Funding; Tolero Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding. Kapoor:Cellectar: Consultancy; Janssen: Research Funding; Sanofi: Consultancy, Research Funding; Amgen: Research Funding; Takeda: Honoraria, Research Funding; Celgene: Honoraria; GlaxoSmithKline: Research Funding. Parikh:MorphoSys: Research Funding; Janssen: Honoraria, Research Funding; AstraZeneca: Honoraria, Research Funding; Merck: Research Funding; AbbVie: Honoraria, Research Funding; Ascentage Pharma: Research Funding; Genentech: Honoraria; Verastem Oncology: Honoraria; GlaxoSmithKline: Honoraria; TG Therapeutics: Research Funding; Pharmacyclics: Honoraria, Research Funding.