FDA Approval Summary: Axicabtagene Ciloleucel for Relapsed or Refractory Follicular Lymphoma

In March 2021, the U.S. Food and Drug Administration granted accelerated approval to axicabtagene ciloleucel, a CD19-directed chimeric antigen receptor T-cell therapy, for the treatment of adult patients with relapsed or refractory follicular lymphoma (r/r FL) after at least 2 lines of systemic therapy. Approval was based on ZUMA-5, a single-arm, open-label, multicenter trial that evaluated a single infusion of axicabtagene ciloleucel, preceded by lymphodepleting chemotherapy with cyclophosphamide and fludarabine, in this population. Efficacy was based on objective response rate (ORR) and duration of response (DOR) as determined by an independent review committee. Among 81 patients in the primary efficacy analysis, having a median of 3 (range 2-9) prior lines of systemic therapy, the ORR was 91% (95% confidence interval [CI]: 83-96) with a complete remission (CR) rate of 60% and a median time-to-response of 1 month. The median DOR was not reached, and the 1-year rate of continued remission was 76% (95% CI: 64-85). For all leukapheresed patients with FL in this trial (n = 123), the ORR was 89% (95% CI: 83-94) with a CR rate of 62%. Among 146 patients with indolent lymphoma evaluated for safety, cytokine release syndrome occurred in 84% (Grade ≥3, 8%) and neurological toxicities occurred in 77% (Grade ≥3, 21%), leading to implementation of a risk evaluation and mitigation strategy. Serious adverse reactions occurred in 48%. Post-marketing studies will further evaluate clinical benefit in patients with r/r FL and long-term safety.     

Safety of Axicabtagene Ciloleucel for the Treatment of Relapsed or Refractory Large B-Cell Lymphoma

BackgroundDiffuse large B-cell lymphoma is the most common type of non-Hodgkin lymphoma. Recent advances in immunotherapy have resulted in the development of chimeric antigen receptor–modified T-cell (CAR-T) therapy, such as axicabtagene ciloleucel (axi-cel). However, axi-cel administration is not without risks of toxicity.Patients and MethodsThis retrospective study of 37 patients with relapsed or refractory diffuse large B-cell lymphoma evaluated the incidence and severity of common and severe safety events after axi-cel treatment in a real-world setting. Ninety percent of patients had received 3 or more prior lines of therapy (median prior therapies 3, range 2-7) before receiving CAR-T therapy, and 32.4% had relapsed after prior stem-cell transplantation.ResultsAll but one patient experienced cytokine release syndrome (CRS) of any grade (97.3%). Of those 36 patients, 83.3% experienced maximum CRS grade of 1 or 2, occurring after a median of 27 hours and persisting for a median of 6 days. Twenty-seven patients (73.0%) experienced neurotoxicity of any grade. Of those 27 patients, 96.3% experienced maximum neurotoxicity grade of 2 or higher, occurring after a median of 145 hours (6 days) and persisting for a median of 7 days. All 10 patients aged 65 or older had neurotoxicity of grade 2 or higher, compared to 59.3% (11/27) under age 65 (P = .02). Patients with baseline Eastern Cooperative Oncology Group performance status score of 2 were significantly more likely to have shorter time to neurotoxicity compared to patients with performance status of 0 (P = .01).ConclusionWith more real-life experience and data, we will be able to define and refine management of toxicities unique to CAR-T therapy.     

Clinical Efficacy and Safety in Relapsed/Refractory Diffuse Large B-Cell Lymphoma: A Systematic Literature Review

This systematic literature review was designed to assess information on the clinical efficacy and safety of interventions used in the treatment of refractory or relapsed diffuse large B-cell lymphoma (R/R DLBCL) and to perform a meta-analysis if possible. We searched databases (PubMed, EMBASE, and Cochrane Library for articles from 1997 to August 2, 2012 reported in English), conference abstracts, bibliographic reference lists, and the ClinicalTrials.gov database for phase II to IV studies with results. Studies had to report on patients with R/R DLBCL who were not eligible to receive high-dose therapy (HDT) with stem cell transplantation (SCT) (autologous or allogeneic). Mixed-type non-Hodgkin lymphoma (NHL) studies were required to report R/R DLBCL outcomes separately. We identified 55 studies that presented outcomes data separately for patients with R/R DLBCL. Of 7 comparative studies, only 4 were randomized controlled trials (RCTs). In the 2 RCTs with a common regimen, the patient populations differed too greatly to perform a valid meta-analysis. The 48 single-arm studies identified were typically small (n < 50 in most), with 31% reporting median progression-free survival (PFS) or overall survival (OS) specifically for the R/R DLBCL population. In these studies, median OS ranged from 4 to 13 months. The small number of RCTs in R/R DLBCL precludes identifying optimal treatments. Small sample size, infrequent reporting of OS and PFS separated by histologic type, and limited information on patient characteristics also hinder comparison of results. Randomized studies are needed to demonstrate which current therapies have advantages for improving survival and other important clinical outcomes in patients with R/R DLBCL.     

Polatuzumab Vedotin for Relapsed/Refractory Aggressive B-cell Lymphoma: A Multicenter Post-marketing Analysis

IntroductionPolatuzumab vedotin is approved therapy in the United States for relapsed/refractory diffuse large B-cell lymphoma in combination with bendamustine and rituximab (Pola+BR). However, the safety and efficacy of Pola+BR outside of a clinical trial setting is unknown.Patients and MethodsWe analyzed use of pola-based therapy at 5 centers in the United States, including dose, response rates, progression-free survival (PFS), survival, and toxicity.ResultsSixty-nine patients with aggressive B-cell lymphoma, including 66 with diffuse large B-cell lymphoma/high-grade B-cell lymphoma and 84% refractory to prior therapy, were treated. Responses occurred in of 50%, including 24% complete response. Median duration of response was 5.1 months, PFS was 2.0 months, and survival was 5.3 months, at 4 months median follow-up. Inferior PFS was associated with prior refractory disease (median, 57 days vs. not reached; P = .003) and lack of response to Pola+BR (PFS, 27 days vs. 152 days; P < .001). Discontinuation owing to planned cellular therapy was seen in 36% and owing to toxicity occurred in 12%; unplanned hospitalizations occurred in 36%.ConclusionsWe conclude that commercial Pola is applied to highly refractory lymphomas at our centers, often with intent to bridge to subsequent therapy. Although some clinical benefit was observed, efficacy was inferior to clinical trial data, especially among those with refractory disease.     

Chimeric Antigen Receptor T-Cell Therapy for Chronic Lymphocytic Leukemia: A Narrative Review

The treatment landscape for chronic lymphocytic leukemia (CLL) is changing rapidly. Novel targeted agents such as ibrutinib, venetoclax, and idelalisib have had a significant effect on first-line, relapsed/refractory, and high-risk disease. Despite these advances, there are continuous needs for new treatment options, especially for patients in whom these novel therapies fail or those who cannot tolerate these novel therapies. In 2011, Porter et al reported the first successful use of autologous chimeric antigen receptor T cells (CARTs) directed against cluster of differentiation (CD)19 in 3 refractory CLL patients. Several groups have since shown success with similar approaches in various settings of CLL, including failure of ibrutinib treatment and in patients who relapse after allogeneic stem cell transplantation. Although CD19-directed CART therapy holds great promise in CLL and other diseases, many challenges and questions remain including: optimization of the lymphodepletion regimen before CART infusion, optimal dosing of CART, a determination of the most effective CART product (T-cell subset[s]) as well as the optimal combinations and therapeutic sequences, and managing treatment-associated adverse events. Clinical trials addressing these challenges are in process. In this timely review, we analyze current state of CART therapy in CLL and attempt answering remaining questions.     

Utility of the Geriatric 8 for the Prediction of Therapy-Related Toxicity in Older Adults with Diffuse Large B-Cell Lymphoma

BackgroundThe management of severe adverse events (AEs) is important in safely and effectively providing chemotherapy to older adults with diffuse large B‐cell lymphoma (DLBCL). However, reports on simple and DLBCL‐specific predictive models for treatment‐related toxicity in elderly individuals are scarce. The aim of this study was to examine the usefulness of Geriatric 8 (G8) in predicting treatment‐related severe AEs, nonhematological toxicity, and febrile neutropenia in older adults with DLBCL in real‐world practice.Materials and MethodsWe conducted a multicenter, retrospective study on 398 consecutive patients with DLBCL (aged ≥65 years) who received standard therapy at three centers in Japan (University of Fukui Hospital, the Fukui Prefectural Hospital, and the Japanese Red Cross Fukui Hospital), between 2007 and 2017.ResultMultivariate logistic analysis demonstrated that the G8 score was an independent predictive factor for severe AEs. Moreover, a logistic regression model with restricted cubic spline showed a nonlinear association between the incidence of severe AEs and the G8 score. According to receiver operating characteristic analysis, the most discriminative cutoff value of the G8 for the incidence of severe AEs was 11, with an area under the curve value of 0.670. AEs occurred most often in the first course of chemotherapy and decreased as the course progressed.ConclusionThe G8 score, an easy‐to‐use geriatric assessment tool, can be a useful prediction model of treatment‐related severe AEs during standard therapy in older adults with DLBCL.Implications for PracticeIn older patients with diffuse large B‐cell lymphoma (DLBCL), to accurately predict the risk of severe adverse events (AEs) in advance is essential for safe and effective treatment. This study demonstrated that the Geriatric 8 score, a simple and established geriatric assessment tool, indicated a high predictive ability for occurrence of therapy‐related severe AEs in elderly patients with DLBCL who were treated with standard treatment.     

Salvage Therapy for Relapsed Mediastinal B-Cell Lymphoma with Allogeneic HLA-Identical Related Donor Bone Marrow Transplantation, Donor Lymphocyte Infusion and IDEC-C2B8

Primary B-cell lymphoma of the mediastinum is an aggressive non-Hodgkin's lymphoma with distinct clinicopathologic features. Response rates are between 60-80% following intensive chemotherapy regimens. Poor responders or patients with an early relapse usually do not achieve a prolonged second remission with conventional salvage therapy protocols and therefore qualify for intensive or experimental approaches. Here we describe two patients of same age, gender and stage with primary mediastinal B-cell lymphoma and an early relapse after the first courses of combination chemotherapy and irradiation of the mediastinum. One patient relapsed after a salvage therapy with allogeneic donor-related bone marrow transplantation and donor lymphocyte infusion but responded again with a continuing good partial remission after infusion of the chimeric anti-CD20 antibody IDEC-C2B8. For the other patient an allogeneic bone marrow transplantation was not possible. He finally failed to respond to salvage therapy with IDEC-C2B8 and died of progressive disease. The anti-CD20 antibody IDEC-C2B8 induced a partial remission in a patient with primary mediastinal B-cell lymphoma refractory to other therapeutic approaches, including allogeneic bone marrow transplanatation (alloBMT), donor lymphocyte infusion (DLI) and irradiation. The role of IDEC-C2B8 as a component of salvage regimens appears to be worthy for further evaluation in high-risk patients with primary mediastinal B-cell lymphoma