Project description:AbstractMore than half of the patients treated with CD19-targeted chimeric antigen receptor (CAR) T-cell immunotherapy for large B-cell lymphoma (LBCL) do not achieve durable remission, which may be partly due to PD-1/PD-L1-associated CAR T-cell dysfunction. We report data from a phase 1 clinical trial (NCT02706405), in which adults with LBCL were treated with autologous CD19 CAR T cells (JCAR014) combined with escalating doses of the anti-PD-L1 monoclonal antibody, durvalumab, starting either before or after CAR T-cell infusion. The addition of durvalumab to JCAR014 was safe and not associated with increased autoimmune or immune effector cell-associated toxicities. Patients who started durvalumab before JCAR014 infusion had later onset and shorter duration of cytokine release syndrome and inferior efficacy, which was associated with slower accumulation of CAR T cells and lower concentrations of inflammatory cytokines in the blood. Initiation of durvalumab before JCAR014 infusion resulted in an early increase in soluble PD-L1 (sPD-L1) levels that coincided with the timing of maximal CAR T-cell accumulation in the blood. In vitro, sPD-L1 induced dose-dependent suppression of CAR T-cell effector function, which could contribute to inferior efficacy observed in patients who received durvalumab before JCAR014. Despite the lack of efficacy improvement and similar CAR T-cell kinetics early after infusion, ongoing durvalumab therapy after JCAR014 was associated with re-expansion of CAR T cells in the blood, late regression of CD19+ and CD19- tumors, and enhanced duration of response. Our results indicate that the timing of initiation of PD-L1 blockade is a key variable that affects outcomes after CD19 CAR T-cell immunotherapy for adults with LBCL.
Project description:Purpose of reviewChimeric antigen receptor (CAR) T cell therapy is an immunotherapy that has resulted in tremendous progress in the treatment of patients with B cell malignancies. However, the remarkable efficacy of therapy is not without significant safety concerns. Herein, we will review the unique and potentially life-threatening toxicities associated with CAR-T cell therapy and their association with treatment efficacy.Recent findingsCurrently, CAR-T cell therapy is approved for the treatment of B cell relapsed or refractory leukemia and lymphoma, and most recently, multiple myeloma (MM). In these different diseases, it has led to excellent complete and overall response rates depending on the patient population and therapy. Despite promising efficacy, CAR-T cell therapy is associated with significant side effects; the two most notable toxicities are cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). The treatment of CAR-T-induced toxicity is supportive; however, as higher-grade adverse events occur, toxicity-directed therapy with tocilizumab, an IL-6 receptor antibody, and steroids is standard practice. Overall, a careful risk-benefit balance exists between the efficacy and toxicities of therapies. The challenge lies in the underlying pathophysiology of CAR-T-related toxicity which relies upon the activation of CAR-T cells. Some degree of toxicity is expected to achieve an effective response to therapy, and certain aspects of treatment are also associated with toxicity. As progress is made in the investigation and approval of new CARs, novel toxicity-directed therapies and toxicity-limited constructs will be the focus of attention.
Project description:Lymphomas arise from clonal expansions of B, T, or NK cells at different stages of differentiation. Because they occur in the immunocyte-rich lymphoid tissues, they are easily accessible to antibodies and cell-based immunotherapy. Expressing chimeric antigen receptors (CARs) on T cells is a means of combining the antigen-binding site of a monoclonal antibody with the activating machinery of a T cell, enabling antigen recognition independent of major histocompatibility complex restriction, while retaining the desirable antitumor properties of a T cell. Here, we discuss the basic design of CARs and their potential advantages and disadvantages over other immune therapies for lymphomas. We review current clinical trials in the field and consider strategies to improve the in vivo function and safety of immune cells expressing CARs. The ultimate driver of CAR development and implementation for lymphoma will be the demonstration of their ability to safely and cost-effectively cure these malignancies.
Project description:BACKGROUND:In a phase 1 trial, axicabtagene ciloleucel (axi-cel), an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, showed efficacy in patients with refractory large B-cell lymphoma after the failure of conventional therapy. METHODS:In this multicenter, phase 2 trial, we enrolled 111 patients with diffuse large B-cell lymphoma, primary mediastinal B-cell lymphoma, or transformed follicular lymphoma who had refractory disease despite undergoing recommended prior therapy. Patients received a target dose of 2×106 anti-CD19 CAR T cells per kilogram of body weight after receiving a conditioning regimen of low-dose cyclophosphamide and fludarabine. The primary end point was the rate of objective response (calculated as the combined rates of complete response and partial response). Secondary end points included overall survival, safety, and biomarker assessments. RESULTS:Among the 111 patients who were enrolled, axi-cel was successfully manufactured for 110 (99%) and administered to 101 (91%). The objective response rate was 82%, and the complete response rate was 54%.With a median follow-up of 15.4 months, 42% of the patients continued to have a response, with 40% continuing to have a complete response. The overall rate of survival at 18 months was 52%. The most common adverse events of grade 3 or higher during treatment were neutropenia (in 78% of the patients), anemia (in 43%), and thrombocytopenia (in 38%). Grade 3 or higher cytokine release syndrome and neurologic events occurred in 13% and 28% of the patients, respectively. Three of the patients died during treatment. Higher CAR T-cell levels in blood were associated with response. CONCLUSIONS:In this multicenter study, patients with refractory large B-cell lymphoma who received CAR T-cell therapy with axi-cel had high levels of durable response, with a safety profile that included myelosuppression, the cytokine release syndrome, and neurologic events. (Funded by Kite Pharma and the Leukemia and Lymphoma Society Therapy Acceleration Program; ZUMA-1 ClinicalTrials.gov number, NCT02348216 .).
Project description:Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin's lymphoma (NHL), representing 30% of all lymphoma cases. Within the first 2-3 years following immunochemotherapy, 30-40% of patients will experience a relapse or a refractory disease, thereby exhibiting a poor prognosis. High-dose immunotherapy followed by autologous stem cell transplantation is the standard care for relapsed/refractory (RR) patients with DLBCL. However, >60% of patients are ineligible for a transplant, presenting a therapeutic challenge. Chimeric antigen receptor (CAR) T-cell therapy has shown promising efficacy in patients with DLBCL, including those with R/R disease. The present study conducted a meta-analysis that showed highly favorable outcomes [objective response rate (ORR): 69%; complete remission (CR): 49%] in B-cell NHL patients (n=419) who were treated with second-generation CAR T cells. The response rate varied in different types of B-cell NHL. In 306 patients with R/R DLBCL eligible for rate evaluation, the ORR and CR rate mean estimates were 68% [95% confidence interval (CI), 55-79%] and 46% (95% CI, 38-54%), respectively. Thus, the findings indicated that immunotherapy with CAR T cells has improved outcomes for patients with R/R DLBCL and other subtypes of B-cell NHL compared with standard chemotherapy regimens. The study revealed that grade ≥3 anemia (34%) and thrombocytopenia (30%) were the most common adverse effects of CAR T-cell therapy. Incidence of grade ≥3 cytokine release syndrome and neurotoxicity associated with CAR T-cell therapy was effectively managed.
Project description:Patients with non-Hodgkin lymphomas (NHLs) resistant to standard therapies have a dismal prognosis. The outcome is even poorer in patients relapsing after autologous stem cell transplantation. Most of these patients do not qualify for an allogeneic hematopoietic cell transplantation (HCT) due to refractory disease, lack of a suitable allogeneic donor, higher age, or cumulative toxicity of previous chemotherapy. Despite patients undergoing allogeneic HCT normally profit from a graft-versus-lymphoma effect, overall survival in patients with NHL after HCT remains short. Therefore, novel treatment modalities are urgently needed. Chimeric antigen receptor (CAR)-T cells, a new class of cellular immunotherapy involving ex vivo genetic modification of T cells to incorporate an engineered CAR have been used in clinical trials. In the majority of studies, B cell malignancies treated with CD19 targeting CAR-T cells have been analyzed. Recently, results from 2 CD19 directed CAR-T cell trials with an increased follow-up of patients led to Food and Drug Administration and European Medicines Agency approval of tisagenlecleucel and axicabtagene ciloleucel. Common adverse events (AEs) include cytokine release syndrome and neurological toxicity, which may require admission to an intensive care unit, B cell aplasia and hemophagocytic lymphohistiocytosis. These AEs are manageable when treated by an appropriately trained team following established algorithm. In this review, we summarize the results of 3 large phase II CD19 CAR-T cell trials and focus on AEs. We also provide a perspective of ongoing activity in this field with the intend to improve the potency of this emerging novel therapy.
Project description:The prognosis of patients with large B-cell lymphoma (LBCL) that progresses after treatment with chimeric antigen receptor (CAR) T-cell therapy targeting CD19 (CAR19) is poor. We report on the first 3 consecutive patients with autologous CAR19-refractory LBCL who were treated with a single infusion of autologous 1 × 106 CAR+ T cells per kilogram targeting CD22 (CAR22) as part of a phase 1 dose-escalation study. CAR22 therapy was relatively well tolerated, without any observed nonhematologic adverse events higher than grade 2. After infusion, all 3 patients achieved complete remission, with all responses continuing at the time of last follow-up (mean, 7.8 months; range, 6-9.3). Circulating CAR22 cells demonstrated robust expansion (peak range, 85.4-350 cells per microliter), and persisted beyond 3 months in all patients with continued radiographic responses and corresponding decreases in circulating tumor DNA beyond 6 months after infusion. Further accrual at a higher dose level in this phase 1 dose-escalation study is ongoing and will explore the role of this therapy in patients in whom prior CAR T-cell therapies have failed. This trial is registered on clinicaltrials.gov as #NCT04088890.
Project description:The phase 3 ZUMA-7 trial in second-line large B cell lymphoma demonstrated superiority of anti-CD19 CAR T cell therapy (axicabtagene ciloleucel (axi-cel)) over standard of care (SOC; salvage chemotherapy followed by hematopoietic transplantation) ( NCT03391466 ). Here, we present a prespecified exploratory analysis examining the association between pretreatment tumor characteristics and the efficacy of axi-cel versus SOC. B cell gene expression signature (GES) and CD19 expression associated significantly with improved event-free survival for axi-cel (P = 0.0002 for B cell GES; P = 0.0165 for CD19 expression) but not SOC (P = 0.9374 for B cell GES; P = 0.5526 for CD19 expression). Axi-cel showed superior event-free survival over SOC irrespective of B cell GES and CD19 expression (P = 8.56 × 10-9 for B cell GES high; P = 0.0019 for B cell GES low; P = 3.85 × 10-9 for CD19 gene high; P = 0.0017 for CD19 gene low). Low CD19 expression in malignant cells correlated with a tumor GES consisting of immune-suppressive stromal and myeloid genes, highlighting the inter-relation between malignant cell features and immune contexture substantially impacting axi-cel outcomes. Tumor burden, lactate dehydrogenase and cell-of-origin impacted SOC more than axi-cel outcomes. T cell activation and B cell GES, which are associated with improved axi-cel outcome, decreased with increasing lines of therapy. These data highlight differences in resistance mechanisms to axi-cel and SOC and support earlier intervention with axi-cel.