Dual targeting of CD19 and CD22 with bicistronic CAR-T cells in patients with relapsed/refractory large B-cell lymphoma.

Relapse after CD19-directed chimeric antigen receptor T-cell (CAR-T) therapy for large B-cell lymphoma (LBCL) is commonly ascribed to antigen loss or CAR-T exhaustion. Multiantigen targeting and programmed cell death protein-1 blockade are rational approaches to prevent relapse. Here, we test CD19/22 dual-targeting CAR-T (AUTO3) plus pembrolizumab in relapsed/refractory LBCL (NCT03289455). End points include toxicity (primary) and response rates (secondary). Fifty-two patients received AUTO3 and 48/52 received pembrolizumab. Median age was 59 years (range, 27-83), 46/52 had stage III/ IV disease and median follow-up was 21.6 months. AUTO3 was safe; grade 1-2 and grade 3 cytokine release syndrome affected 18/52 (34.6%) and 1/52 (1.9%) patients, neurotoxicity arose in 4 patients (2/4, grade 3-4), and hemophagocytic lymphohistiocytosis affected 2 patients. Outpatient administration was tested in 20 patients, saving a median of 14 hospital days per patient. Overall response rates were 66% (48.9%, complete response [CR]; 17%, partial response). Median duration of remission (DOR) for CR patients was not reached and for all responding patients was 8.3 months (95% confidence interval [CI]: 3.0-not evaluable). 54.4% (CI: 32.8-71.7) of CR patients and 42.6% of all responding patients were projected to remain progression-free at ≥12 months. AUTO3 ± pembrolizumab for relapsed/refractory LBCL was safe and delivered durable remissions in 54.4% of complete responders, associated with robust CAR-T expansion. Neither dual-targeting CAR-T nor pembrolizumab prevented relapse in a significant proportion of patients, and future developments include next-generation-AUTO3, engineered for superior expansion in vivo, and selection of CAR binders active at low antigen densities.

Infectious complications following CAR-t cell therapy for B cell non-Hodgkin lymphoma: a single-center experience and review of the literature.

Chimeric antigen receptor T-cell (CAR-T) therapy targeting CD19 has significantly improved outcomes in the treatment of refractory or relapsed (R/R) B-cell non-Hodgkin lymphoma (NHL). Several risk factors including CAR-T cell-related toxicities and their treatments often lead to infectious complications (ICs); however, the pattern and timeline is not well established. We evaluated ICs in 48 patients with R/R B-cell NHL following CAR-T cell therapy at our institution. Overall, 15 patients experienced 22 infection events. Eight infections (4 bacterial, 3 viral and 1 fungal) occurred within the first 30 days and 14 infections (7 bacterial, 6 viral, 1 fungal) between days 31 to 180 following CAR-T infusion. Most infections were mild-to-moderate and fifteen infections involved the respiratory tract. Two patients developed mild-to-moderate COVID-19 infection and one patient a cytomegalovirus reactivation after CAR-T infusion. Two patients developed IFIs: one case each of fatal disseminated candidiasis and invasive pulmonary aspergillosis at day 16 and 77, respectively. Patients with more than 4 prior antitumor regimens and patient's ≥ 65 years had a higher infection rate. Infections in patients with relapsed/refractory B-cell NHL are common after CAR-T despite the use of infection prophylaxis. Age ≥ 65 years and having > 4 prior antitumor treatments were identified as risk factors for infection. Fungal infections carried significant impact in morbidity and mortality, suggesting a role for increase fungal surveillance and/or anti-mold prophylaxis following high-dose steroids and tocilizumab. Four of ten patients developed an antibody response following two doses of SARS-CoV-2 mRNA vaccine.

Impact of SARS-CoV-2 vaccination and monoclonal antibodies on outcome post-CD19-directed CAR T-cell therapy: an EPICOVIDEHA survey.

Patients with previous CD19-directed chimeric antigen receptor (CAR) T-cell therapy have a prolonged vulnerability to viral infections. Coronavirus disease 2019 (COVID-19) has a great impact and has previously been shown to cause high mortality in this population. Until now, real-world data on the impact of vaccination and treatment on patients with COVID-19 after CD19-directed CAR T-cell therapy are lacking. Therefore, this multicenter, retrospective study was conducted with data from the EPICOVIDEHA survey. Sixty-four patients were identified. The overall mortality caused by COVID-19 was 31%. Patients infected with the Omicron variant had a significantly lower risk of death due to COVID-19 compared with patients infected with previous variants (7% vs 58% [P = .012]). Twenty-six patients were vaccinated at the time of the COVID-19 diagnosis. Two vaccinations showed a marked but unsignificant reduction in the risk of COVID-19-caused mortality (33.3% vs 14.2% [P = .379]). In addition, the course of the disease appears milder with less frequent intensive care unit admissions (39% vs 14% [P = .054]) and a shorter duration of hospitalization (7 vs 27.5 days [P = .022]). Of the available treatment options, only monoclonal antibodies seemed to be effective at reducing mortality from 32% to 0% (P = .036). We conclude that survival rates of CAR T-cell recipients with COVID-19 improved over time and that the combination of prior vaccination and monoclonal antibody treatment significantly reduces their risk of death. This trial was registered at www.clinicaltrials.gov as #NCT04733729.

Vaccinations in hematological patients in the era of target therapies: Lesson learnt from SARS-CoV-2.

Novel targeting agents for hematologic diseases often exert on- or off-target immunomodulatory effects, possibly impacting on response to anti-SARS-CoV-2 vaccinations and other vaccines. Agents that primarily affect B cells, particularly anti-CD20 monoclonal antibodies (MoAbs), Bruton tyrosine kinase inhibitors, and anti-CD19 chimeric antigen T-cells, have the strongest impact on seroconversion. JAK2, BCL-2 inhibitors and hypomethylating agents may hamper immunity but show a less prominent effect on humoral response to vaccines. Conversely, vaccine efficacy seems not impaired by anti-myeloma agents such as proteasome inhibitors and immunomodulatory agents, although lower seroconversion rates are observed with anti-CD38 and anti-BCMA MoAbs. Complement inhibitors for complement-mediated hematologic diseases and immunosuppressants used in aplastic anemia do not generally affect seroconversion rate, but the extent of the immune response is reduced under steroids or anti-thymocyte globulin. Vaccination is recommended prior to treatment or as far as possible from anti-CD20 MoAb (at least 6 months). No clearcut indications for interrupting continuous treatment emerged, and booster doses significantly improved seroconversion. Cellular immune response appeared preserved in several settings.

Asymptomatic COVID-19 Reinfection in a Pediatric Patient with Heterotaxy Syndrome.

We report an asymptomatic child with heterotaxy syndrome who had recurrent positive SARS-CoV-2 polymerase chain reaction testing. An aberrant lymphocyte population expressing CD19, CD16, and CD56 was identified; its phenotyping revealing atypical NK cells. This subset's role in protection from severe disease or in reinfection cannot be ascertained.

Cytokine release syndrome and associated neurotoxicity in cancer immunotherapy.

A paradigm shift has recently occurred in the field of cancer therapeutics. Traditional anticancer agents, such as chemotherapy, radiotherapy and small-molecule drugs targeting specific signalling pathways, have been joined by cellular immunotherapies based on T cell engineering. The rapid adoption of novel, patient-specific cellular therapies builds on scientific developments in tumour immunology, genetic engineering and cell manufacturing, best illustrated by the curative potential of chimeric antigen receptor (CAR) T cell therapy targeting CD19-expressing malignancies. However, the clinical benefit observed in many patients may come at a cost. In up to one-third of patients, significant toxicities occur that are directly associated with the induction of powerful immune effector responses. The most frequently observed immune-mediated toxicities are cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome. This Review discusses our current understanding of their pathophysiology and clinical features, as well as the development of novel therapeutics for their prevention and/or management.

Specific Antibody and the T-Cell Response Elicited by BNT162b2 Boosting After Two ChAdOx1 nCoV-19 in Common Variable Immunodeficiency.

Common variable immunodeficiency (CVID) patients have markedly decreased immune response to vaccinations. In this study we evaluated humoral and T cell-mediated responses against severe acute respiratory syndrome coronavirus-2 (SARS-Cov-2) with additional flow cytometric changes in CVID patients receiving booster vaccination with BNT162b2 after two ChAdOx1 nCoV-19. The BNT162b2 vaccine raised the anti-spike protein S immunoglobulin G over the cut-off value from 70% to 83% in CVID, anti-neutralizing antibody had been raised over a cut-off value from 70% to 80% but levels after boosting were significantly less in both tests than in healthy controls (*p=0.02; **p=0.009 respectively). Anti-SARS-CoV-2 immunoglobulin A became less positive in CVID after boosting, but the difference was not significant. The cumulative interferon-γ positive T cell response by ELISpot was over the cut-off value in 53% of the tested individuals and raised to 83% after boosting. This and flow cytometric control of cumulative CD4+ and CD8+ virus-specific T cell absolute counts in CVID were also statistically not different from healthy individuals after boosting. Additional flow cytometric measures for CD45+ lymphocytes, CD3+, and CD19+ cells have not shown significant differences from controls except for lower CD4+T cell counts at both time points (**p=0.003; **p=0.002), in parallel CD4+ virus-specific T-cell ratio was significantly lower in CVID patients at the first time point (*p: 0.03). After boosting, in more than 33% of both CVID patients and also in their healthy controls we detected a decrease in absolute CD45+, CD3+, CD3+CD4+, and CD3+CD8+, CD19+, and CD16+56+ cell counts. CD16+CD56+ cell counts were significantly lower compared to controls before and after boosting (*p=0.02, *p=0.02). CVID patients receiving immunosuppressive therapy throughout the previous year or autologous stem cell transplantation two years before vaccination had worse responses in anti-spike, anti-neutralizing antibody, CD3+CD4+T, CD19+ B, and natural killer cell counts than the whole CVID group. Vaccinations had few side effects. Based on these data, CVID patients receiving booster vaccination with BNT162b2 after two ChadOx1 can effectively elevate the levels of protection against COVID-19 infection, but the duration of the immune response together with COVID-19 morbidity data needs further investigation among these patients.

Post-Marketing Surveillance of CAR-T-Cell Therapies: Analysis of the FDA Adverse Event Reporting System (FAERS) Database.

INTRODUCTION: As chimeric antigen receptor T-cell therapies are becoming increasingly available in the armamentarium of the hematologist, there is an emerging need to monitor post-marketing safety. OBJECTIVE: We aimed to better characterize their safety profile by focusing on cytokine release syndrome and identifying emerging signals. METHODS: We queried the US Food and Drug Administration Adverse Event Reporting System (October 2017-September 2020) to analyze suspected adverse drug reactions to tisagenlecleucel (tisa-cel) and axicabtagene ciloleucel (axi-cel). Disproportionality analyses (reporting odds ratio) were performed by comparing chimeric antigen receptor T-cell therapies with (a) all other drugs (reference group 1) and (b) other onco-hematological drugs with a similar indication, irrespective of age (reference group 2), or (c) restricted to adults (reference group 3). Notoriety was assessed through package inserts and risk management plans. Adverse drug reaction time to onset and cytokine release syndrome features were investigated. RESULTS: Overall, 3225 reports (1793 axi-cel; 1433 tisa-cel) were identified. The reported toxicities were mainly: cytokine release syndrome (52.2%), febrile disorders (27.7%), and neurotoxicity (27.2%). Cytokine release syndrome and neurotoxicity were often co-reported and 75% of the events occurred in the first 10 days. Disproportionalities confirmed known adverse drug reactions and showed unexpected associations: for example, axi-cel with cardiomyopathies (reporting odds ratio = 2.3; 95% confidence interval 1.2-4.4) and gastrointestinal perforations (2.9; 1.2-7.3), tisa-cel with hepatotoxicity (2.5; 1.1-5.7) and pupil disorders (15.3; 6-39.1). CONCLUSIONS: Our study confirms the well-known adverse drug reactions and detects potentially emerging safety issues specific for each chimeric antigen receptor T-cell therapy, also providing insights into a stronger role for tisa-cel in inducing some immunodeficiency-related events (e.g., hypogammaglobulinemia, infections) and coagulopathies, and for axi-cel in neurotoxicity.

GLA/DRST real-world outcome analysis of CAR T-cell therapies for large B-cell lymphoma in Germany.

CD19-directed chimeric antigen receptor (CAR) T cells have evolved as a new standard-of-care (SOC) treatment in patients with relapsed/refractory (r/r) large B-cell lymphoma (LBCL). Here, we report the first German real-world data on SOC CAR T-cell therapies with the aim to explore risk factors associated with outcomes. Patients who received SOC axicabtagene ciloleucel (axi-cel) or tisagenlecleucel (tisa-cel) for LBCL and were registered with the German Registry for Stem Cell Transplantation (DRST) were eligible. The main outcomes analyzed were toxicities, response, overall survival (OS), and progression-free survival (PFS). We report 356 patients who received axi-cel (n = 173) or tisa-cel (n = 183) between November 2018 and April 2021 at 21 German centers. Whereas the axi-cel and tisa-cel cohorts were comparable for age, sex, lactate dehydrogenase (LDH), international prognostic index (IPI), and pretreatment, the tisa-cel group comprised significantly more patients with poor performance status, ineligibility for ZUMA-1, and the need for bridging, respectively. With a median follow-up of 11 months, Kaplan-Meier estimates of OS, PFS, and nonrelapse mortality (NRM) 12 months after dosing were 52%, 30%, and 6%, respectively. While NRM was largely driven by infections subsequent to prolonged neutropenia and/or severe neurotoxicity and significantly higher with axi-cel, significant risk factors for PFS on the multivariate analysis included bridging failure, elevated LDH, age, and tisa-cel use. In conclusion, this study suggests that important outcome determinants of CD19-directed CAR T-cell treatment of LBCL in the real-world setting are bridging success, CAR-T product selection, LDH, and the absence of prolonged neutropenia and/or severe neurotoxicity. These findings may have implications for designing risk-adapted CAR T-cell therapy strategies.

Plasmablast-like Phenotype Among Antigen-Experienced CXCR5-CD19low B Cells in Systemic Lupus Erythematosus.

OBJECTIVE: Altered composition of the B cell compartment in the pathogenesis of systemic lupus erythematosus (SLE) is characterized by expanded plasmablast and IgD-CD27- double-negative B cell populations. Previous studies showed that double-negative B cells represent a heterogeneous subset, and further characterization is needed. METHODS: We analyzed 2 independent cohorts of healthy donors and SLE patients, using a combined approach of flow cytometry (for 16 healthy donors and 28 SLE patients) and mass cytometry (for 18 healthy donors and 24 SLE patients) and targeted RNA-Seq analysis. To compare B cell subset formation during the acute immune response versus that during autoimmune disease, we investigated healthy donors at various time points after receipt of the BNT162b2 messenger RNA COVID-19 vaccine and patients with acute SARS-CoV-2 infection, using flow cytometry. RESULTS: We found that IgD-CD27+ switched and atypical IgD-CD27- memory B cells, the levels of which were increased in SLE patients, represented heterogeneous populations composed of 3 different subsets each. CXCR5+CD19intermediate , CXCR5-CD19high , and CXCR5-CD19low populations were found in the switched memory and double-negative compartments, suggesting the relatedness of IgD-CD27+ and IgD-CD27- B cells. We characterized a hitherto unknown and antigen-experienced CXCR5-CD19low subset that was enhanced in SLE patients, had a plasmablast phenotype with diminished B cell receptor responsiveness, and expressed CD38, CD95, CD71, PRDM1, XBP1, and IRF4. Levels of CXCR5-CD19low subsets were increased and correlated with plasmablast frequencies in SLE patients and in healthy donors who received BNT162b2, suggesting their interrelationship and contribution to plasmacytosis. The detection of CXCR5-CD19low B cells among both CD27+ and CD27- populations calls into question the role of CD27 as a reliable marker of B cell differentiation. CONCLUSION: Our data suggest that CXCR5-CD19low B cells are precursors of plasmablasts. Thus, cotargeting this subset may have therapeutic value in SLE.

Outcomes of Tisagenlecleucel in Lymphoma Patients With Predominant Management in an Ambulatory Setting.

INTRODUCTION: Chimeric antigen receptor T-cell therapy (CAR T) is a revolutionary adoptive immunotherapy approach in lymphoma; however, substantial resources are necessary for administration and care of these patients. Our institution has administered tisagenlecleucel primarily in an outpatient setting, and here we report our clinical outcomes. PATIENTS AND METHODS: We conducted a single institution, retrospective study investigating outcomes of adult lymphoma patients treated with commercial tisagenlecleucel between 10/2017 and 12/2020. We analyzed patient characteristics and outcomes of efficacy and safety including overall response rate, progression-free survival, overall survival and cytokine-release syndrome, neurotoxicity, and hospitalizations. RESULTS: Seventy-two patients with relapsed or refractory non-Hodgkin lymphoma (NHL) who received commercial tisagenlecleucel were identified; 68 (94.4%) patients received outpatient tisagenlecleucel. The overall response rate was 43% with a complete response observed in 25 patients (34.7%). At a median follow-up of 9.1 months, the median progression-free survival was 3.3 months. Grade 3-4 cytokine release syndrome was not observed in the study group and two patients had grade 3-4 neurotoxicity. Twenty-six patients (36.1%) were admitted within 30 days after infusion with a median length of stay of 5 days. Fourteen patients (19.4%) were admitted within 72 hours of infusion. No patient died of CAR T cell-related toxicity. CONCLUSION: Our experience affirms treatment with tisagenlecleucel in the outpatient setting is safe and feasible with close supervision and adequate institutional experience. After infusion, adverse events were manageable and the majority of patients did not require hospitalization.

Programmed Cell Death-1/Programmed Cell Death-1 Ligand as Prognostic Markers of Coronavirus Disease 2019 Severity.

Current research proves that immune dysregulation is a common feature of coronavirus disease 2019 (COVID-19), and immune exhaustion is associated with increased disease mortality. Immune checkpoint molecules, including the programmed cell death-1 (PD-1)/PD-1 ligand (PD-L1) axis, may serve as markers of disease severity. Accordingly, in this study, we evaluated the expression of PD-1/PD-L1 in patients with COVID-19. Blood immunophenotypes of hospitalized patients with moderate (n = 17, requiring oxygen support) and severe (n = 35, requiring mechanical ventilation in the intensive care setting) COVID-19 were compared and associated with clinical, laboratory, and survival data. The associations between severity and lymphocyte profiles were analysed at baseline and after 7 and 14 days of in-hospital treatment. Forty patients without COVID-19 infection were used as controls. For PD-1-positive T and B lymphocyte subsets, notable increases were observed between controls and patients with moderate or severe COVID-19 for CD4+PD-1+ T cells, CD8+PD-1+ T and CD19+PD-1+ B cells. Similar trends were observed for PD-L1-positive lymphocytes, namely, CD4+PD-L1+ T cells, CD8+PD-L1+ T cells and CD19+PD-L1+ B cells. Importantly, all markers associated with PD-1 and PD-L1 were stable over time for the analysed time points in the moderate and severe COVID-19 groups. Increased abundances of PD-1+ and PD-L1+ lymphocytes were associated with disease severity and mortality and were stable over time in patients with moderate to severe COVID-19. These immune exhaustion parameters may be attractive biomarkers of COVID-19 severity.

Axicabtagene ciloleucel as first-line therapy in high-risk large B-cell lymphoma: the phase 2 ZUMA-12 trial.

High-risk large B-cell lymphoma (LBCL) has poor outcomes with standard first-line chemoimmunotherapy. In the phase 2, multicenter, single-arm ZUMA-12 study (ClinicalTrials.gov NCT03761056) we evaluated axicabtagene ciloleucel (axi-cel), an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, as part of first-line treatment in 40 patients with high-risk LBCL. This trial has completed accrual. The primary outcome was complete response rate (CRR). Secondary outcomes were objective response rate (ORR), duration of response (DOR), event-free survival (EFS), progression-free survival (PFS), overall survival (OS), assessment of safety, central nervous system (CNS) relapse and blood levels of CAR T cells and cytokines. The primary endpoint in efficacy-evaluable patients (n = 37) was met, with 78% CRR (95% confidence interval (CI), 62-90) and 89% ORR (95% CI, 75-97). As of 17 May 2021 (median follow-up, 15.9 months), 73% of patients remained in objective response; median DOR, EFS and PFS were not reached. Grade ≥3 cytokine release syndrome (CRS) and neurologic events occurred in three patients (8%) and nine patients (23%), respectively. There were no treatment-related grade 5 events. Robust CAR T-cell expansion occurred in all patients with a median time to peak of 8 days. We conclude that axi-cel is highly effective as part of first-line therapy for high-risk LBCL, with a manageable safety profile.

Immune Responses to SARS-CoV-2 Vaccination in Young Patients with Anti-CD19 Chimeric Antigen Receptor T Cell-Induced B Cell Aplasia.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines are capable of inducing combined humoral and cellular immunity. Which effect is more relevant for their potent protective effects is unclear, but isolated T cell responses without seroconversion in healthy household members of individuals with Coronavirus disease 19 (COVID-19) suggest that T cell responses effectively protect against clinical infection. Oncologic patients have an outsize risk of unfavorable outcomes after SARS-CoV-2 infection and therefore were prioritized when vaccines first became available, although the quality of their immune response to vaccination was expected to be suboptimal, as has been confirmed in subsequent studies. Inherently, patients with anti-CD19 chimeric antigen receptor (CAR) T cell therapy-mediated B cell aplasia would be incapable of generating humoral responses, so that assessment of the vaccine-induced cellular immunity is all the more important to gauge whether the vaccine can induce meaningful protection. A salient difference between T cell and humoral responses is the former's relative impassiveness to mutations of the antigen, which is more relevant than ever since the advent of the omicron variant. The objective of this study was to assess the immune cell composition and spike protein-specific T cell responses before and after the first and second doses of SARS-CoV-2 mRNA vaccine in a cohort of juvenile CD19 CAR T cell therapy recipients with enduring B cell aplasia. The prospective study included all patients age >12 years diagnosed with multiply relapsed B cell precursor acute lymphoblastic leukemia and treated with anti-CD19 CAR T cell (CAR-T19) therapy in our center. The primary endpoint was the detection of cell-mediated and humoral responses to vaccine (flow cytometry and anti-S immunoglobulin G, respectively). Secondary endpoints included the incidence of vaccine-related grade 3 or 4 adverse events, exacerbation of graft-versus-host disease (GVHD), relapse, and the influence of the vaccine on CAR T cells and lymphocyte subsets. Even though one-half of the patients exhibited subnormal lymphocyte counts and marginal CD4/CD8 ratios, after 2 vaccinations all showed brisk T-cell responsiveness to spike protein, predominantly in the CD4 compartment, which quantitatively was well within the range of healthy controls. No severe vaccine-related grade 3 or 4 adverse events, GVHD exacerbation, or relapse was observed in our cohort. We posit that SARS-CoV-2 mRNA vaccines induce meaningful cellular immunity in patients with isolated B cell deficiency due to CAR-T19 therapy.

Robust immune responses to SARS-CoV-2 in a pediatric patient with B-Cell ALL receiving tisagenlecleucel.

Recipients of anti-CD19 targeted therapies such as chimeric antigen receptor (CAR)-T cell are considered at high risk for complicated Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) infection due to prolonged B cell aplasia and immunosuppression. These patients represent a unique cohort and so far, immune responses to SARS-CoV-2 have not been well characterized in this setting. We report a pediatric patient with B-cell acute lymphoblastic leukemia (B-ALL) who had asymptomatic SARS-CoV-2 infection while receiving blinatumomab, followed by lymphodepletion (LD) and tisagenlecleucel, a CD19 targeting CAR-T therapy. The patient had a complete response to tisagenlecleucel, did not develop cytokine release syndrome, or worsening of SARS-CoV-2 during therapy. The patient had evidence of ongoing persistence of IgG antibody responses to spike and nucleocapsid after LD followed by tisagenlecleucel despite the B-cell aplasia. Further we were able to detect SARS-CoV-2 specific T-cells recognizing multiple viral structural proteins for several months following CAR-T. The T-cell response was polyfunctional and predominantly CD4 restricted. This data has important implications for the understanding of SARS-CoV-2 immunity in patients with impaired immune systems and the potential application of SARS-CoV-2-specific T-cell therapeutics to treat patients with blood cancers who receive B cell depleting therapy.