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:BackgroundIn 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.MethodsIn 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.ResultsAmong 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.ConclusionsIn 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: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:Chimeric antigen receptor- (CAR-) T cell therapy is one of the most recent innovative immunotherapies and is rapidly evolving. Like other technologies, CAR-T cell therapy has undergone a long development process, and persistent explorations of the actions of the intracellular signaling domain and make several improvements have led to the superior efficacy when anti-CD19 CAR-T cell treatments in B cell cancers. At present, CAR-T cell therapy is developing rapidly, and many clinical trials have been established on a global scale, which has great commercial potential. This review mainly describes the toxicity of CAR-T cell therapy and the challenges of CAR-T cells in the treatment of solid tumors, and looks forward to future development and opportunities for immunotherapy and reviews major breakthroughs in CAR-T cell therapy.
Project description:PURPOSE OF REVIEW:Modern immunotherapies, most notably in the form of anti-CD19 chimeric antigen receptor (CAR) T cells, have produced significant clinical responses in otherwise refractory pre-B-cell acute lymphoblastic leukemia patients. Several groups have simultaneously reported robust response rates in children and adults alike. These early studies indicate an impending shift in paradigm for the treatment of acute lymphoblastic leukemia. Incorporating CD19 CAR T-cell therapy into upfront or salvage regimens has its challenges and opportunities. RECENT FINDINGS:Most CD19 CAR T-cell products in trial today are excellent at inducing minimal residual disease negative remissions, and most responding patients experience cytokine release syndrome and/or neurotoxicity. The challenges facing the CAR community involve how best to minimize the severity of cytokine release syndrome and neurotoxicity while maximizing antitumor efficacy, determining what role this therapy will play for the prophylaxis and treatment of central nervous system leukemia, and its implications on subsequent hematopoietic stem cell transplant given the emergence of CD19-negative relapses. SUMMARY:CD19 CAR T-cell therapy is a powerful new tool in the oncologist's arsenal. How it is incorporated into standard practice and how it will shift survival curves are the exciting questions that are waiting to be answered.
Project description:Taking advantage of the immune system to exert an antitumor effect is currently a novel approach in cancer therapy. Adoptive transfer of T cells engineered to express chimeric antigen receptors (CARs) targeting a desired antigen has shown extraordinary antitumor activity, especially in refractory and relapsed B-cell malignancies. The most representative in this respect, as well as the most successful example, is CD19 CAR T-cell therapy in B-cell acute lymphoblastic leukemia (B-ALL). However, with the widespread use of CAR T-cell therapy, problems of resistance and relapse are starting to be considered. This review provides a comprehensive picture of the mechanisms of resistance to CAR T-cell therapy from three aspects, namely, CAR T-cell factors, tumor factors, and tumor microenvironment factors, offering insights for improving CAR T-cell therapy.
Project description:Chimeric antigen receptor-modified (CAR) T-cell therapy targeting CD19 has revolutionized the treatment of relapsed or refractory B-cell lymphomas. Based on unprecedented response rates and durability of response in high risk B-cell lymphoma patients, anti-CD19 CAR T-cell therapy was rapidly approved by the FDA for a variety of lymphoma subtypes. Anti-CD19 CAR T-cell therapy is now considered standard of care for patients with relapsed or refractory (R/R) aggressive non-Hodgkin's Lymphoma (NHL) after 2 or more lines of therapy. Three second-generation anti-CD19 CAR T-cell products have been FDA approved for R/R aggressive B-cell lymphoma and FDA approval has been obtained for Mantle Cell Lymphoma and Follicular lymphoma as well. This has ensured broad access to CAR T-cell therapy for patients with NHL and new real-world trials have helped confirm feasibility of CAR T-cell therapy for a broad patient population. The emergence of CAR T-cell therapy will likely provide a new patient population who is status post anti-CD19 CAR T-cell therapy. Investigation of mechanisms of failure of CAR T-cell therapy and clinical trials to study strategies to address this are thus required. Here we provide a thorough review on the use of the FDA approved anti-CD19 CAR T-cell products axicabtagene ciloleucel, tisagenlecleucel, and lisocabtagene maraleucel in patients with indolent or aggressive B-cell lymphoma, and touch on mechanisms of failure of CAR T-cell therapy and potential approaches which are currently under investigation to address this.
Project description:Patients with relapsed and/or refractory (R/R) follicular lymphoma (FL) and mantle cell lymphoma (MCL) have a poor prognosis with anticipated short progression-free and overall survivals. Two CD19-directed chimeric antigen receptor T-cell (CAR T) therapies are approved in the United States for R/R FL, namely, axicabtagene ciloleucel (axi-cel) and tisagenlecleucel. The results of ZUMA-5 and ELARA studies led to the approval of axi-cel and tisagenlecleucel, respectively, after demonstrating high overall (ORR) and complete response (CR) rates in this high-risk population of FL patients who had received a median of 3 (range = 2-4) and 4 (range = 2-13) prior lines of therapies, respectively. For instance, the ORR for ZUMA-5 was 94% (CR = 79%), and for ELARA, it was 86% (CR = 69.1%). Pertaining to MCL, brexucabtagene autoleucel is approved for R/R MCL based on results of the ZUMA-2 study. In the latter study, despite the fact that all R/R MCL patients had been exposed to prior Bruton's tyrosine kinase inhibitors, the reported ORR was 91%, with 68% achieving a CR. These results undoubtedly demonstrate a strong efficacy of CAR T therapy in both R/R FL and MCL; yet, one must acknowledge the relatively short follow-up time of all aforementioned studies. Thus, longer follow-up showing durability of responses and long-term safety is definitely needed.