Gene Expression Risk Scores for COVID-19 Illness Severity.

BACKGROUND: The correlates of coronavirus disease 2019 (COVID-19) illness severity following infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are incompletely understood. METHODS: We assessed peripheral blood gene expression in 53 adults with confirmed SARS-CoV-2 infection clinically adjudicated as having mild, moderate, or severe disease. Supervised principal components analysis was used to build a weighted gene expression risk score (WGERS) to discriminate between severe and nonsevere COVID-19. RESULTS: Gene expression patterns in participants with mild and moderate illness were similar, but significantly different from severe illness. When comparing severe versus nonsevere illness, we identified >4000 genes differentially expressed (false discovery rate < 0.05). Biological pathways increased in severe COVID-19 were associated with platelet activation and coagulation, and those significantly decreased with T-cell signaling and differentiation. A WGERS based on 18 genes distinguished severe illness in our training cohort (cross-validated receiver operating characteristic-area under the curve [ROC-AUC] = 0.98), and need for intensive care in an independent cohort (ROC-AUC = 0.85). Dichotomizing the WGERS yielded 100% sensitivity and 85% specificity for classifying severe illness in our training cohort, and 84% sensitivity and 74% specificity for defining the need for intensive care in the validation cohort. CONCLUSIONS: These data suggest that gene expression classifiers may provide clinical utility as predictors of COVID-19 illness severity.

Host Gene Expression in Nose and Blood for the Diagnosis of Viral Respiratory Infection.

BACKGROUND: Recently there has been a growing interest in the potential for host transcriptomic analysis to augment the diagnosis of infectious diseases. METHODS: We compared nasal and blood samples for evaluation of the host transcriptomic response in children with acute respiratory syncytial virus (RSV) infection, symptomatic non-RSV respiratory virus infection, asymptomatic rhinovirus infection, and virus-negative asymptomatic controls. We used nested leave-one-pair-out cross-validation and supervised principal components analysis to define small sets of genes whose expression patterns accurately classified subjects. We validated gene classification scores using an external data set. RESULTS: Despite lower quality of nasal RNA, the number of genes detected by microarray in each sample type was equivalent. Nasal gene expression signal derived mainly from epithelial cells but also included a variable leukocyte contribution. The number of genes with increased expression in virus-infected children was comparable in nasal and blood samples, while nasal samples also had decreased expression of many genes associated with ciliary function and assembly. Nasal gene expression signatures were as good or better for discriminating between symptomatic, asymptomatic, and uninfected children. CONCLSUSIONS: Our results support the use of nasal samples to augment pathogen-based tests to diagnose viral respiratory infection.

Phase 2 study of imexon, a prooxidant molecule, in relapsed and refractory B-cell non-Hodgkin lymphoma.

Lymphoma cells are subject to higher levels of oxidative stress compared with their normal counterparts and may be vulnerable to manipulations of the cellular redox balance. We therefore designed a phase 2 study of imexon (Amplimexon/NSC-714597), a prooxidant molecule, in patients with relapsed/refractory B-cell non-Hodgkin lymphoma (NHL). Imexon was administered at 1000 mg/m(2) IV daily for 5 days in 21-day cycles. Gene expression analysis performed on pretreatment tumor specimens included 13 transcripts used to generate a redox signature score, previously demonstrated to correlate with lymphoma prognosis. Twenty-two patients were enrolled having follicular (n = 9), diffuse large B-cell (DLBCL) (n = 5), mantle cell (n = 3), transformed follicular (n = 2), small lymphocytic (n = 2), and Burkitt (n = 1) lymphoma. The most common grade 3/4 adverse events were anemia (14%) and neutropenia (9%). The overall response rate was 30%, including responses in follicular lymphoma (4 of 9) and DLBCL (2 of 5). Gene expression analyses revealed CD68 and the redox-related genes, GPX1 and SOD2, as well as a higher redox score to correlate with clinical responses. Therefore, pretreatment markers of oxidative stress may identify patients likely to respond to this therapeutic approach. This trial was registered at www.clinicaltrials.gov as #NCT01314014.

Response-adapted, time-limited venetoclax, umbralisib, and ublituximab for relapsed/refractory chronic lymphocytic leukemia.

ABSTRACT: Many patients with chronic lymphocytic leukemia (CLL) will develop treatment resistance to Bruton tyrosine kinase (BTK) inhibitors. Phosphatidylinositol-3-kinase (PI3K) inhibitors, including umbralisib, have significant clinical activity in relapsed/refractory CLL, but prolonged exposure is associated with potential toxicities. Owing to the synergistic antitumor effects of combined PI3K and BCL-2 inhibition, we sought to explore the feasibility of response-adapted, time-limited therapy to optimize disease control while mitigating the risks of prolonged treatment. We conducted a phase 1/2 clinical trial to determine the safety and efficacy of venetoclax in combination with umbralisib and the anti-CD20 monoclonal antibody, ublituximab, (U2-VeN) in patients with relapsed/refractory CLL (N = 46) and Richter transformation (N = 5). After 12 cycles, treatment was stopped for patients with CLL who achieved undetectable minimal residual disease (uMRD). Adverse events of special interest included diarrhea in 50% of patients (11% grade 3/4), and aspartate aminotransferase and/or alanine aminotransferase elevation in 15 patients (33%), with 3 (7%) grade 3/4. There were no cases of tumor lysis syndrome related to venetoclax, with outpatient initiation in 96% of patients. The intent-to-treat overall response rate for CLL was 98% with best response of 100% in evaluable patients (42% complete responses). The end-of-treatment rate of uMRD at 10-4 in bone marrow was 77% (30/39), including a 71% uMRD rate among 14 patients refractory to prior BTK inhibitor. Time-limited venetoclax and U2 is safe and highly effective combination therapy for patients with relapsed/refractory CLL including those who have been previously treated with covalent BTK inhibitors. This trial was registered on www.clinicaltrials.gov as #NCT03379051.

The role of splenectomy in management of splenic B-cell lymphomas.

INTRODUCTION: Splenic B-cell lymphomas are rare and understudied entities. Splenectomy is frequently required for specific pathological diagnosis in patients with splenic B-cell lymphomas other than classical hairy cell leukemia (cHCL), and can be effective and durable therapy. Our study investigated the diagnostic and therapeutic role of splenectomy for non-cHCL indolent splenic B-cell lymphomas. METHODS: Observational study of patients with non-cHCL splenic B-cell lymphoma undergoing splenectomy between 1 August 2011 and 1 August 2021 at the University of Rochester Medical Center. The comparison cohort was patients categorized as having non-cHCL splenic B-cell lymphoma who did not undergo splenectomy. RESULTS: Forty-nine patients (median age 68 years) had splenectomy (SMZL n = 33, HCLv n = 9, SDRPL n = 7) with median follow up of 3.9 years post splenectomy. One patient had fatal post-operative complications. Post-operative hospitalization was ≤ 4 days for 61% and ≤ 10 days for 94% of patients. Splenectomy was initial therapy for 30 patients. Of the 19 patients who had previous medical therapy, splenectomy changed their lymphoma diagnosis in 5 (26%). Twenty-one patients without splenectomy were clinically categorized as having non-cHCL splenic B-cell lymphoma. Nine required medical treatment for progressive lymphoma and of these 3 (33%) required re-treatment for lymphoma progression compared to 16% of patients following first line splenectomy. CONCLUSION: Splenectomy is useful for the diagnosis of non-cHCL splenic B-cell lymphomas with comparable risk/benefit profile and remission duration to medical therapy. Patients with suspected non-cHCL splenic lymphomas should be considered for referral to a high-volume center with experience in performing splenectomies for definitive diagnosis and treatment.

Acalabrutinib and high-frequency low-dose subcutaneous rituximab for initial therapy of chronic lymphocytic leukemia.

Bruton tyrosine kinase inhibitors are an effective therapeutic agent for previously untreated patients with chronic lymphocytic leukemia but require indefinite treatment that can result in cumulative toxicities. Novel combinations of agents that provide deep remissions could allow for fixed duration therapy. Acalabrutinib, unlike ibrutinib, does not inhibit anti-CD20 monoclonal antibody-dependent cellular phagocytosis, making it a suitable partner drug to rituximab. Using standard dosing (375 mg/m2) of rituximab causes loss of target membrane CD20 cells and exhaustion of the finite cytotoxic capacity of the innate immune system. Alternatively, using high-frequency, low-dose (HFLD), subcutaneous rituximab limits loss of CD20 and allows for self-administration at home. The combination of HFLD rituximab 50 mg administered twice a week for 6 cycles of 28 days with the addition of acalabrutinib starting in week 2 was evaluated in a phase II study of 38 patients with treatment naive chronic lymphocytic leukemia. Patients achieving a complete response with undetectable minimal residual disease after 12 or 24 cycles of acalabrutinib could stop therapy. All patient responded, including one with a complete response with undetectable minimal residual disease in the peripheral blood and bone marrow at 12 months who stopped therapy. At a median follow-up of 2.3 years 2 patients with high-risk features have progressed while on acalabrutinib monotherapy. We conclude that HFLD rituximab in combination with acalabrutinib is an effective and tolerable self-administered home combination that provides a platform to build upon regimens that may more reliably allow for fixed-duration therapy. This trial was registered at www.clinicaltrials.gov #NCT03788291.

Referral to and receipt of allogeneic hematopoietic stem cell transplantation in older adults with acute myeloid leukemia.

INTRODUCTION: Recent data have shown improved outcomes in selected older adults with acute myeloid leukemia (AML) following allogeneic hematopoietic stem cell transplantation (HSCT). Nonetheless, practice patterns for referring and performing HSCT vary. We aimed to evaluate referral, utilization, and reasons for not referring/proceeding to HSCT in older adults with AML. MATERIALS AND METHODS: This is a single center retrospective analysis of patients aged ≥60 years diagnosed with AML evaluating rates of HSCT referral and utilization. Fisher's exact test was used to compare rates of referral and utilization across age groups and years of diagnosis. RESULTS: Median age of the 97 patients was 70 years (range 61-95); 30% (29/97) were referred for HSCT and of these, 69% (20/29) received HSCT. Common documented reasons (can be multiple) for not referring were performance status (n = 21), advanced age (n = 16), patient refusal (n = 15), refractory disease (n = 14), and prohibitive comorbidity (n = 6). Among patients who were referred but did not receive HSCT (n = 9/29), documented reasons for not proceeding with HSCT were refractory disease (n = 5), advanced age (n = 2), and prohibitive comorbidity (n = 2). HSCT referral and utilization rates significantly decreased with age (p < 0.01) but were generally stable over time from 2014 to 2017 (p = 0.40 for referral and p = 0.56 for utilization). DISCUSSION: Despite improvements in supportive care and HSCT techniques, HSCT referral and utilization rates remained low among older adults with AML but stable over time.

Rituximab induced cytokine release with high serum IP-10 (CXCL10) concentrations is associated with infusion reactions.

Monoclonal antibody induced infusion reactions (IRs) can be serious and even fatal. We used clinical data and blood samples from 37 treatment naïve patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) initiating therapy for progressive disease with a single 50 mg dose of intravenous (IV) rituximab at 25 mg/h. Twenty-four (65 %) patients had IRs at a median of 78 min (range 35-128) and rituximab dose of 32 mg (range 15-50). IR risk did not correlate with patient or CLL characteristics, CLL counts or CD20 levels, or serum rituximab or complement concentrations. Thirty-five (95 %) patients had cytokine release response with a ≥ 4-fold increase in serum concentration of ≥ 1 inflammatory cytokine. IRs were associated with significantly higher post-infusion serum concentrations of gamma interferon induced cytokines IP-10, IL-6 and IL-8. IP-10 concentrations increased ≥ 4-fold in all patients with an IR and were above the upper limit of detection (40,000 pg/ml) in 17 (71 %). In contrast, to only three (23 %) patients without an IR had an ≥ 4-fold increase in serum concentrations of IP-10 (highest 22,013 pg/ml). Our data suggest that cytokine release could be initiated by activation of effector cells responsible for clearance of circulating CLL cells with IRs occurring in those with higher levels of gamma interferon induced cytokines. These novel insights could inform future research to better understand and manage IRs and understand the role of cytokines in the control of cytotoxic immune responses to mAb.

Targeted therapy for treatment of patients with classical hairy cell leukemia.

Most patients with treatment naïve classical hairy cell leukemia (cHCL) have durable responses with purine nucleoside analogues. In contrast, options are limited for cHCL patients with co-morbidities, purine analogue intolerance, or resistant disease. We report the utility of targeted therapy for nine cHCL patients presenting with treatment naïve cHCL and severe neutropenia and infection (n = 3), purine analogue intolerance (n = 2), or purine analogue resistant disease (n = 4). BRAF inhibitor vemurafenib was started at 240-480 mg twice daily (planned 90-day treatment) and combined with rituximab in seven patients. Therapy was tolerable with no severe adverse events. All patients responded with rapid blood count recovery (median time 1.52 months, range 0.43-4.33). Median progression free and overall survival was not reached at a median follow up of 18.1 months (range 3.2-68.9). These data suggest targeted therapy could be an option for patients unable to be treated with purine analogues.

Gene Expression Risk Scores for COVID-19 Illness Severity.

BACKGROUND: The correlates of COVID-19 illness severity following infection with SARS-Coronavirus 2 (SARS-CoV-2) are incompletely understood. METHODS: We assessed peripheral blood gene expression in 53 adults with confirmed SARS-CoV-2-infection clinically adjudicated as having mild, moderate or severe disease. Supervised principal components analysis was used to build a weighted gene expression risk score (WGERS) to discriminate between severe and non-severe COVID. RESULTS: Gene expression patterns in participants with mild and moderate illness were similar, but significantly different from severe illness. When comparing severe versus non-severe illness, we identified >4000 genes differentially expressed (FDR<0.05). Biological pathways increased in severe COVID-19 were associated with platelet activation and coagulation, and those significantly decreased with T cell signaling and differentiation. A WGERS based on 18 genes distinguished severe illness in our training cohort (cross-validated ROC-AUC=0.98), and need for intensive care in an independent cohort (ROC-AUC=0.85). Dichotomizing the WGERS yielded 100% sensitivity and 85% specificity for classifying severe illness in our training cohort, and 84% sensitivity and 74% specificity for defining the need for intensive care in the validation cohort. CONCLUSION: These data suggest that gene expression classifiers may provide clinical utility as predictors of COVID-19 illness severity.

Portable medical orders and end-of-life measures in acute myeloid leukemia and myelodysplastic syndromes.

Patients with acute myeloid leukemia (AML) or a myelodysplastic syndrome (MDS) experience high rates of hospitalization, intensive care unit (ICU) admission, and in-hospital death at the end of life. Early goals-of-care (GOC) discussions may reduce the intensity of end-of-life (EOL) care. Portable Medical Order forms, known as Medical Orders for Life-Sustaining Treatment (MOLST) forms in New York state, assist patients in translating GOC discussions into specific medical orders that communicate their wishes during a medical emergency. To determine whether the timing of completion of a MOLST form is associated with EOL care in patients with AML or MDS, we conducted a retrospective study of 358 adult patients with AML or MDS treated at a single academic center and its affiliated sites, who died during a 5-year period. One-third of patients completed at least 1 MOLST form >30 days before death. Compared with patients who completed a MOLST form within 30 days of death or never, those who completed a MOLST form >30 days before death were less likely to receive transfusion (adjusted odds ratio [AOR], 0.39; P < .01), chemotherapy (AOR, 0.24; P < .01), or life-sustaining treatments (AOR, 0.21; P < .01) or to be admitted to the ICU (AOR, 0.21; P < .01) at EOL. They were also more likely to use hospice services (AOR, 2.72; P < .01). Earlier MOLST form completion was associated with lower intensity of care near EOL in patients with MDS or AML.

Lymphocyte-Specific Biomarkers Associated With Preterm Birth and Bronchopulmonary Dysplasia.

Many premature babies who are born with neonatal respiratory distress syndrome (RDS) go on to develop Bronchopulmonary Dysplasia (BPD) and later Post-Prematurity Respiratory Disease (PRD) at one year corrected age, characterized by persistent or recurrent lower respiratory tract symptoms frequently related to inflammation and viral infection. Transcriptomic profiles were generated from sorted peripheral blood CD8+ T cells of preterm and full-term infants enrolled with consent in the NHLBI Prematurity and Respiratory Outcomes Program (PROP) at the University of Rochester and the University at Buffalo. We identified outcome-related gene expression patterns following standard methods to identify markers for oxygen utilization and BPD as outcomes in extremely premature infants. We further identified predictor gene sets for BPD based on transcriptomic data adjusted for gestational age at birth (GAB). RNA-Seq analysis was completed for CD8+ T cells from 145 subjects. Among the subjects with highest risk for BPD (born at <29 weeks gestational age (GA); n=72), 501 genes were associated with oxygen utilization. In the same set of subjects, 571 genes were differentially expressed in subjects with a diagnosis of BPD and 105 genes were different in BPD subjects as defined by physiologic challenge. A set of 92 genes could predict BPD with a moderately high degree of accuracy. We consistently observed dysregulation of TGFB, NRF2, HIPPO, and CD40-associated pathways in BPD. Using gene expression data from both premature and full-term subjects (n=116), we identified a 28 gene set that predicted the PRD status with a moderately high level of accuracy, which also were involved in TGFB signaling. Transcriptomic data from sort-purified peripheral blood CD8+ T cells from 145 preterm and full-term infants identified sets of molecular markers of inflammation associated with independent development of BPD in extremely premature infants at high risk for the disease and of PRD among the preterm and full-term subjects.

Additional B-cell malignancies in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL).

Family and migration studies suggest a genetic risk of developing chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL). We hypothesized that CLL patients have an increased risk of additional clonally unrelated B-cell malignancies. To test this, we studied 467 CLL patients (2743 person-years (PYs)) at a single institution over 17 years. The incidence rate (IR) of any additional B-cell lymphoid malignancy was 10.9 per 1000 PYs (n = 30, 6.4%). Eighteen (4%) patients had a clonally unrelated B-cell malignancy (IR = 6.6 per 1000 PYs). Standardized incidence ratios (SIRs) were used to compare the incidence of additional clonally unrelated B-cell malignancies in CLL patients to the age- and sex-matched expected rates in the USA generated from the Surveillance, Epidemiology, and End Results (SEER) database. For the subset of 13 patients having data for comparison in the SEER database, the SIR was 5.41 (95% CI = 2.9, 9.3) which is supportive of our hypothesis.

Ibrutinib Dose Adherence and Therapeutic Efficacy in Non-Hodgkin Lymphoma: A Single-Center Experience.

BACKGROUND: As oral targeted agents, such as ibrutinib, become more widely used, understanding the impact of suboptimal dosing on overall survival (OS) and progression-free survival (PFS) outside of clinical trials is imperative. PATIENTS AND METHODS: Data on ibrutinib discontinuation, dose reductions, and treatment interruptions were collected on 170 non-Hodgkin lymphoma and chronic lymphocytic leukemia (CLL; n = 115, 64%) patients treated with ibrutinib at a single institution. Ibrutinib dose adherence was calculated as the proportion of days in which ibrutinib was administered out of the total number of days ibrutinib was prescribed in the first 8 weeks. Kaplan-Meier curves and log-rank tests were used to compare conditional survival outcomes beyond 8 weeks in patients with ≥ 80% dose adherence and patients with < 80% dose adherence. RESULTS: Median OS among those who discontinued therapy for progression was poor (n = 51, 1.7 months; 95% confidence interval, 0.3-3.7). Lower dose adherence (< 80%) was associated with significantly worse PFS (P = .002) and OS (P = .021). However, among CLL patients, lower dose adherence was only associated with worse PFS (P = .043). Patients with early dose reductions had significantly worse PFS (P = .004) and OS (P = .014). Patients with dose interruptions lasting > 1 week had worse PFS (P = .047) but not OS (P = .577). CONCLUSION: In this observational study, non-Hodgkin lymphoma and CLL patients experienced poor outcomes after discontinuing ibrutinib for disease progression. The inferior survival related to suboptimal dose adherence of ibrutinib was predominantly due to early dose reduction. These data confirm poor survival in CLL and lymphoma patients alike after ibrutinib discontinuation, and support recommendations for full dose at treatment initiation.

Cellular Cytotoxicity of Next-Generation CD20 Monoclonal Antibodies.

CD20 monoclonal antibodies (CD20 mAb) induce cellular cytotoxicity, which is traditionally measured by antibody-dependent cellular cytotoxicity (ADCC) assays. However, data suggest that antibody-dependent cellular phagocytosis (ADCP) is the primary cytotoxic mechanism. We directly compared in vitro ADCP versus ADCC using primary human cells. After establishing the primacy of ADCP, we examined next-generation CD20 mAbs, including clinically relevant drug combinations for their effects on ADCP. ADCP and ADCC induction by rituximab, ofatumumab, obinutuzumab, or ocaratuzumab was measured using treatment-naïve chronic lymphocytic leukemia (CLL) target cells and either human monocyte-derived macrophages (for ADCP) or natural killer (NK) cells (for ADCC). Specific effects on ADCP were evaluated for clinically relevant drug combinations using BTK inhibitors (ibrutinib and acalabrutinib), PI3Kδ inhibitors (idelalisib, ACP-319, and umbralisib), and the BCL2 inhibitor venetoclax. ADCP (∼0.5-3 targets/macrophage) was >10-fold more cytotoxic than ADCC (∼0.04-0.1 targets/NK cell). ADCC did not correlate with ADCP. Next-generation mAbs ocaratuzumab and ofatumumab induced ADCP at 10-fold lower concentrations than rituximab. Ofatumumab, selected for enhanced complement activation, significantly increased ADCP in the presence of complement. CD20 mAb-induced ADCP was not inhibited by venetoclax and was less inhibited by acalabrutinib versus ibrutinib and umbralisib versus idelalisib. Overall, ADCP was a better measure of clinically relevant mAb-induced cellular cytotoxicity, and next-generation mAbs could activate ADCP at significantly lower concentrations, suggesting the need to test a wide range of dose sizes and intervals to establish optimal therapeutic regimens. Complement activation by mAbs can contribute to ADCP, and venetoclax, acalabrutinib, and umbralisib are preferred candidates for multidrug therapeutic regimens. Cancer Immunol Res; 6(10); 1150-60. ©2018 AACR.

Management of melanoma in patients with chronic lymphocytic leukemia.

Melanoma is significantly more common and is associated with a poorer prognosis in patients with an underlying B-cell malignancy. This study reports on the management of patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) and a subsequent diagnosis of melanoma. In the Wilmot Cancer Institute CLL cohort, which includes 470 patients followed for 2849 person-years, 18 patients (3.8%) developed 22 melanomas. Fourteen melanomas were invasive, a significantly higher rate as compared with the age and sex matched general population (standardized incidence ratio [SIR] 6.32 (95% CI 3.45; 10.60). Melanomas were most often detected (n = 15; 68.2%) through active surveillance in a dermatology clinic. Most melanomas (n = 17; 77.3%) were detected at a non-advanced stage (pathological stage grouping < III). The most common management was wide local excision without sentinel lymph node biopsy (n = 13, 59.1%). Management for the 4 (18.2%) patients with metastatic disease included the immune checkpoint inhibitor (ICI) pembrolizumab (n = 1), systemic chemotherapy with dacarbazine (n = 1), and palliative care (n = 2). The patient treated with ICI is in sustained remission of her melanoma after 23 cycles of therapy while her TP53 disrupted CLL continues to respond to ibrutinib therapy. We conclude that patients with CLL may benefit from active surveillance for melanoma leading to early excision of locally-manageable disease. In patients with metastatic melanoma, combined treatment with targeted kinase inhibitors and ICIs can be successful and tolerable. Larger prospective studies should be considered to further evaluate these approaches.

Analysis of the risk of infection in patients with chronic lymphocytic leukemia in the era of novel therapies.

We studied the risk of infections in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL). Major infections were defined as requiring hospital admission or intravenous antimicrobial treatment. Incidence rate (IR) ratios (IRR) were used to compare infection rates. Of 263 CLL patients followed for 936.9 person-years, 60% required treatment for progressive CLL (66 received ibrutinib). Infections occurred in 71.9% patients (IR 92.4/100 person-years) with 31.9% having major infections (IR 20.3/100 person-years) and infections causing 37.5% of deaths. CLL treatment was associated with significantly higher risk of major (IRR 3.31, 95% CI 2.10, 5.21) and minor (IRR 1.78, 95% CI 1.43, 2.22) infections. Compared to their previous chemoimmunotherapy patients receiving salvage ibrutinib therapy (n = 47) had a significantly increased risk of a major infection (IRR 2.35 95% CI 1.27, 4.34). The risk of infection in CLL patients remains high even with use of less immunosuppressive therapies.