Patients with large B-cell lymphoma (LBCL) who experience relapsed disease after CD19-directed chimeric antigen receptor (CAR) T-cell (CAR-T) therapy have a poor prognosis. Bispecific antibodies (BsAbs) induce complete remissions in ∼35% of these cases. Hypothesizing overlapping LBCL-intrinsic resistance mechanisms as well as common poor prognosis predictors to CAR-T and BsAb therapy, we conducted a multicenter retrospective analysis including 92 patients with relapsed/refractory (R/R) LBCL treated with BsAbs after CAR-T failure. Overall response rate (ORR) was 43%, with a progression-free survival (PFS) of 2.8 months. Patients receiving BsAbs during early relapse (≤3 months) achieved a significantly worse outcome (ORR, 29%; PFS, 2.2 months) compared with patients with an intermediate (4-6 months; ORR, 54%; PFS, 3.7 months) or a late relapse (>6 months; ORR, 60%; PFS, 10.5 months). The benefit of later relapse was particularly notable in patients receiving BsAbs as first salvage therapy compared with those receiving a BsAb in subsequent lines (PFS not reached vs 2.7 months; overall survival not reached vs 9.1 months, respectively). In addition to early R/R state before BsAbs, elevated lactate dehydrogenase and higher International Prognostic Index score were significant predictors of poor outcomes to BsAb in multivariate Cox regression analyses. The finding that patients with early relapse after CAR-T respond particularly poorly to BsAb highlights the necessity for alternative treatment options in this high-risk patient cohort.

Glofitamab, a bispecific antibody targeting CD20 and CD3, is approved for relapsed/refractory diffuse large B-cell lymphoma (r/r DLBCL) after at least 2 prior treatment lines, but real-world data are scarce. In this retrospective, multicenter, multinational study, we evaluated the outcomes of 70 patients with r/r DLBCL treated with glofitamab as part of the compassionate use patient program in Germany, Austria, and Switzerland. The median number of prior treatment lines was 4, with 71% of patients refractory to their last treatment. Cytokine release syndrome was observed in 40% of patients (grade 3-4 in 2%), immune effector cell–associated neurotoxicity syndrome in 10% (grade 3 in 1%), and infections in 31% (grade 5 in 3%). The overall response rate was 46%, with 27% achieving complete responses (CR) and 19% partial responses. The median progression-free survival (PFS) was 3.6 months, whereas the median overall survival was 5.7 months. Notably, 13 patients (19%) were in CR 6 months after initiating glofitamab and exhibited durable responses. Elevated lactate dehydrogenase is the most robust predictor of inferior outcome. Patients pretreated with bendamustine within 6 months prior to glofitamab initiation exhibited significantly reduced PFS, suggesting that bendamustine may impair T-cell fitness and hence glofitamab efficacy. In summary, glofitamab demonstrates promising efficacy and a manageable safety profile in heavily pretreated patients with r/r DLBCL in a real-world scenario and the optimal sequence of treatments should use T-cell–depleting agents before glofitamab with caution.

Efficacy and toxicity of chimeric antigen receptor T (CAR-T) cell therapy in relapsed/refractory (r/r) diffuse large B-cell lymphoma (DLBCL) with central nervous system (CNS) involvement remain understudied. Here we analyzed the outcomes of CAR-T cell therapy in r/r DLBCL patients with CNS involvement and compared them with patients without CNS disease. Retrospective and monocentric comparative analysis of patient cohort with r/r DLBCL treated with CAR-T cell therapy: 15 patients with CNS versus 65 patients without CNS involvement. Overall response rates (80% versus 80%; P = 1.0), progression-free survival (P = 0.157), and overall survival (P = 0.393) were comparable for both cohorts. The frequency of cytokine release syndrome was comparable in the CNS and non-CNS cohorts; 93% versus 80%; P = 1.0. Numerically, immune effector-cell–associated neurotoxicity syndrome (all grades) was more frequent in patients with CNS manifestation (53% versus 29%; P = 0.063), although no grade 4 events were documented. Our study suggests that CAR-T cell therapy is effective and feasible in patients with r/r DLBCL and CNS manifestation.

Background: Multi-omics studies have shown a high and lack of common driver mutations in most thymomas (TH) and thymic carcinomas (TC) that hamper the development of novel treatment approaches. However, deregulation of apoptosis has been proposed as a common hallmark of TH and TC. BH3 profiling can be utilized to study the readiness of living cancer cells to undergo apoptosis and their dependency on pro-survival BCL-2 family proteins. Methods: We screened a cohort of 62 TH and TC patient samples for expression of BCL-2 family proteins and used the TC cell line 1889c and native TH for dynamic BH3 profiling and treatment with BH3 mimetics. Results: Immunohistochemical overexpression of MCL-1 and BCL-xL was a strong prognostic marker of TH and TC, and BH3 profiling indicated a strong dependency on MCL-1 and BCL-xL in TH. Single inhibition of MCL-1 resulted in increased binding of BIM to BCL-xL as an escape mechanism that the combined inhibition of both factors could overcome. Indeed, the inhibition of MCL-1 and BCL-xL in combination induced apoptosis in a caspase-dependent manner in untreated and MCL-1-resistant 1889c cells. Conclusion: TH and TC are exquisitely dependent on the pro-survival factors MCL-1 and BCL-xL, making them ideal candidates for co-inhibition by BH3 mimetics. Since TH show a heterogeneous dependency on BCL-2 family proteins, upfront BH3 profiling could select patients and tailor the optimal therapy with the least possible toxicity.

T-prolymphocytic leukemia (T-PLL) is a mature T-cell neoplasm associated with marked chemotherapy resistance and continued poor clinical outcomes. Current treatments, that is, the CD52-antibody alemtuzumab, offer transient responses, with relapses being almost inevitable without consolidating allogeneic transplantation. Recent more detailed concepts of T-PLL’s pathobiology fostered the identification of actionable vulnerabilities: (1) altered epigenetics, (2) defective DNA damage responses, (3) aberrant cell-cycle regulation, and (4) deregulated prosurvival pathways, including T-cell receptor and JAK/STAT signaling. To further develop related preclinical therapeutic concepts, we studied inhibitors of histone deacetylases ([H]DACs), B-cell lymphoma 2 (BCL2), cyclin-dependent kinase (CDK), mouse double minute 2 (MDM2), and classical cytostatics, using (1) single-agent and combinatorial compound testing in 20 well-characterized and molecularly profiled primary T-PLL (validated by additional 42 cases) and (2) 2 independent murine models (syngeneic transplants and patient-derived xenografts). Overall, the most efficient/selective single agents and combinations (in vitro and in mice) included cladribine, romidepsin ([H]DAC), venetoclax (BCL2), and/or idasanutlin (MDM2). Cladribine sensitivity correlated with expression of its target RRM2. T-PLL cells revealed low overall apoptotic priming with heterogeneous dependencies on BCL2 proteins. In additional 38 T-cell leukemia/lymphoma lines, TP53 mutations were associated with resistance toward MDM2 inhibitors. P53 of T-PLL cells, predominantly in wild-type configuration, was amenable to MDM2 inhibition, which increased its MDM2-unbound fraction. This facilitated P53 activation and downstream signals (including enhanced accessibility of target-gene chromatin regions), in particular synergy with insults by cladribine. Our data emphasize the therapeutic potential of pharmacologic strategies to reinstate P53-mediated apoptotic responses. The identified efficacies and their synergies provide an informative background on compound and patient selection for trial designs in T-PLL.

We present the case of a 64-year-old man diagnosed with large B-cell lymphoma who relapsed twice after standard-of-care therapy. Due to persisting cytopenia, Next generation sequencing analysis was performed, revealing a small TP53-mutated clone. As a third-line therapy, the patient was treated with CAR-T cells, which resulted in complete remission. However, this treatment also led to the expansion of the TP53-mutated clone and therapy-related myelodysplasia with a complex aberrant karyotype. This case may serve as a paradigmatic example of clonal hematopoietic progression in a patient undergoing CAR-T cell therapy, especially in the context of a TP53-mutated clone.