The standard of care treatment strategy for patients with relapsed or refractory large B-cell lymphoma (LBCL) has been high-dose chemotherapy followed by autologous stem cell transplantation (ASCT) ...if chemotherapy sensitive in suitable patients. Because of treatment intensity, this approach has only been feasible in half of patients and because of chemotherapy resistance has only been successful in a quarter of transplant-eligible patients. Chimeric antigen receptor (CAR) T-cell therapy, using genetically modified autologous T cells targeting CD19, has been approved for third-line therapy of LBCL and has been associated with durable remissions in a proportion of patients. In this review, we interpret the design and results of 3 randomized phase 3 trials comparing CAR T-cell therapy and ASCT and their implications for CAR T-cell therapy as a potential new standard of care for second-line treatment in appropriate patients with refractory or early relapsing LBCL.
Although the majority of patients with diffuse large B-cell lymphoma (DLBCL) can be cured with standard rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP), patients who ...fail R-CHOP have a dismal outcome. Thus, optimization of front-line therapy, as well as the development of more effective salvage strategies, remains an important objective. Advances in molecular genetics have vastly improved our understanding of the biological diversity of DLBCL and have led to the discovery of key oncogenic pathways. In addition to the major molecular designations of germinal center B-cell and activated B-cell subtypes, next-generation sequencing technologies have unveiled the remarkable complexity of DLBCL and identified unique molecular targets that may be differentially exploited for therapeutic benefit. These findings have translated into a growing list of promising novel agents. Moving forward, it is of paramount importance to recognize the heterogeneity of DLBCL and to investigate these targeted agents within patient populations who are most likely to benefit. It will be necessary to prioritize drugs that affect key driver pathways and to combine them rationally to optimize their benefit. Improved prognostication and the availability of predictive biomarkers will be crucial to allow for the possibility of individualized risk-adapted therapy.
Summary
While rituximab has dramatically improved outcomes for patients with CD20+ malignancies for two decades, responses are not universal and resistance can develop. Obinutuzumab was developed to ...potentiate activity and overcome resistance. Pre‐clinical data suggests obinutuzumab is superior to rituximab at effecting B cell depletion; however recent phase III clinical trial results have been mixed. The decision of which antibody to employ will probably be further complicated by the approval of a subcutaneous preparation of rituximab and several anti‐CD20 biosimilars. Clinicians are now challenged with deciding whether to switch to obinutuzumab in approved settings, accepting the potential for increased toxicity and probable increased cost. The benefit conferred by obinutuzumab over rituximab may be context‐specific and vary based on histological subtype and immune integrity. This comprehensive review will explore the preclinical differences, investigate the proposed pathogenesis of rituximab resistance, compare the employed dosing strategies and interrogate available clinical results to help inform practice.
Management of relapsed/refractory DLBCL Sarkozy, Clémentine; Sehn, Laurie H.
Best practice & research. Clinical haematology,
September 2018, 2018-09-00, 20180901, Letnik:
31, Številka:
3
Journal Article
Recenzirano
Diffuse large B cell lymphoma represents the most common type of non-Hodgkin lymphoma. Although the curability rate is high, around 40% of patients will relapse or exhibit refractory disease. To ...obtain long-term disease-free survival after relapse, an intensive salvage regimen followed by autologous steam cell transplant remains the standard of care. However, more than 60% of patients will be transplant ineligible, presenting a therapeutic challenge. In this setting, there is no definitive standard approach, as management should be individualized according to patient tolerance. Importantly, these transplant ineligible patients are ideal for consideration of novel agents. In this review, we will discuss the incidence, outcome, and management of relapsed and refractory DLBCL, as well as explore some of the novel agents in development.
Follicular lymphoma (FL) is an indolent, yet incurable B cell malignancy. A subset of patients experience an increased mortality rate driven by two distinct clinical end points: histological ...transformation and early progression after immunochemotherapy. The nature of tumor clonal dynamics leading to these clinical end points is poorly understood, and previously determined genetic alterations do not explain the majority of transformed cases or accurately predict early progressive disease. We contend that detailed knowledge of the expansion patterns of specific cell populations plus their associated mutations would provide insight into therapeutic strategies and disease biology over the time course of FL clinical histories.
Using a combination of whole genome sequencing, targeted deep sequencing, and digital droplet PCR on matched diagnostic and relapse specimens, we deciphered the constituent clonal populations in 15 transformation cases and 6 progression cases, and measured the change in clonal population abundance over time. We observed widely divergent patterns of clonal dynamics in transformed cases relative to progressed cases. Transformation specimens were generally composed of clones that were rare or absent in diagnostic specimens, consistent with dramatic clonal expansions that came to dominate the transformation specimens. This pattern was independent of time to transformation and treatment modality. By contrast, early progression specimens were composed of clones that were already present in the diagnostic specimens and exhibited only moderate clonal dynamics, even in the presence of immunochemotherapy. Analysis of somatic mutations impacting 94 genes was undertaken in an extension cohort consisting of 395 samples from 277 patients in order to decipher disrupted biology in the two clinical end points. We found 12 genes that were more commonly mutated in transformed samples than in the preceding FL tumors, including TP53, B2M, CCND3, GNA13, S1PR2, and P2RY8. Moreover, ten genes were more commonly mutated in diagnostic specimens of patients with early progression, including TP53, BTG1, MKI67, and XBP1.
Our results illuminate contrasting modes of evolution shaping the clinical histories of transformation and progression. They have implications for interpretation of evolutionary dynamics in the context of treatment-induced selective pressures, and indicate that transformation and progression will require different clinical management strategies.
The recently developed International Consensus (IC) classification of hematologic neoplasms is primarily based on input from clinical advisory committees composed of pathologists, hematologists, ...oncologists, and genomic scientists. Morphology continues to represent a fundamental element in the definition of hematologic neoplasms. Acknowledging that the abnormal morphology is a result of dysregulated hematopoiesis driven by somatic gene mutations or altered expression, the IC classification considers genomic features more extensively. Defining nosologic entities based on underlying molecular mechanism(s) of disease is fundamental for enabling the development of precision treatments. Because translational and clinical research continuously advance the field, the classification of hematologic neoplasms will need to be regularly refined and updated; the basic question is what mechanism should be used for this purpose. Scientific hematopathology societies, in collaboration with hematology societies, should be primarily responsible for establishing a standing International Working Group, which would in turn collaborate with the World Health Organization (WHO)/International Agency for Research on Cancer (IARC) to realize and disseminate the classification. The current classification, with its strong morphology component, represents a basis for refinement. Through data sharing, the creation of large comprehensive patient data sets will allow the use of methods of inference, including statistical analyses and machine learning models, aimed at further identifying distinct disease subgroups. A collaborative clinico-pathologic review process will provide a mechanism for updating pathologic and genomic criteria within a clinical context. An interactive Web-based portal would make the classification more immediately available to the scientific community, while providing accessory features that enable the practical application of diagnostic, prognostic, and predictive information.
Patients with transplantation-ineligible relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) fare poorly, with limited treatment options. The antibody-drug conjugate polatuzumab vedotin ...targets CD79b, a B-cell receptor component.
Safety and efficacy of polatuzumab vedotin with bendamustine and obinutuzumab (pola-BG) was evaluated in a single-arm cohort. Polatuzumab vedotin combined with bendamustine and rituximab (pola-BR) was compared with bendamustine and rituximab (BR) in a randomly assigned cohort of patients with transplantation-ineligible R/R DLBCL (primary end point: independent review committee IRC assessed complete response CR rate at the end of treatment). Duration of response, progression-free survival (PFS), and overall survival (OS) were analyzed using Kaplan-Meier and Cox regression methods.
Pola-BG and pola-BR had a tolerable safety profile. The phase Ib/II pola-BG cohort (n = 27) had a CR rate of 29.6% and a median OS of 10.8 months (median follow-up, 27.0 months). In the randomly assigned cohort (n = 80; 40 per arm), pola-BR patients had a significantly higher IRC-assessed CR rate (40.0%
17.5%;
= .026) and longer IRC-assessed PFS (median, 9.5
3.7 months; hazard ratio HR, 0.36, 95% CI, 0.21 to 0.63;
< .001) and OS (median, 12.4
4.7 months; HR, 0.42; 95% CI, 0.24 to 0.75;
= .002; median follow-up, 22.3 months). Pola-BR patients had higher rates of grade 3-4 neutropenia (46.2%
33.3%), anemia (28.2%
17.9%), and thrombocytopenia (41%
23.1%), but similar grade 3-4 infections (23.1%
20.5%), versus the BR group. Peripheral neuropathy associated with polatuzumab vedotin (43.6% of patients) was grade 1-2 and resolved in most patients.
Polatuzumab vedotin combined with BR resulted in a significantly higher CR rate and reduced the risk of death by 58% compared with BR in patients with transplantation-ineligible R/R DLBCL.
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