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PURPOSE Epcoritamab is a subcutaneously administered CD3xCD20 T-cell–engaging, bispecific antibody that activates T cells, directing them to kill malignant CD20+ B cells. Single-agent epcoritamab previously demonstrated potent antitumor activity in dose escalation across B-cell non-Hodgkin lymphoma subtypes. PATIENTS AND METHODS In the dose-expansion cohort of a phase I/II study (ClinicalTrials.gov identifier: NCT03625037 ), adults with relapsed or refractory CD20+ large B-cell lymphoma and at least two prior therapy lines (including anti-CD20 therapies) received subcutaneous epcoritamab in 28-day cycles (once weekly step-up doses in weeks 1-3 of cycle 1, then full doses once weekly through cycle 3, once every 2 weeks in cycles 4-9, and once every 4 weeks in cycle 10 and thereafter) until disease progression or unacceptable toxicity. The primary end point was overall response rate by the independent review committee. RESULTS As of January 31, 2022, 157 patients were treated (median age, 64 years [range, 20‐83]; median of three [range, 2-11] prior therapy lines; primary refractory disease: 61.1%; prior chimeric antigen receptor (CAR) T-cell exposure: 38.9%). At a median follow-up of 10.7 months, the overall response rate was 63.1% (95% CI, 55.0 to 70.6) and the complete response rate was 38.9% (95% CI, 31.2 to 46.9). The median duration of response was 12.0 months (among complete responders: not reached). Overall and complete response rates were similar across key prespecified subgroups. The most common treatment-emergent adverse events were cytokine release syndrome (49.7%; grade 1 or 2: 47.1%; grade 3: 2.5%), pyrexia (23.6%), and fatigue (22.9%). Immune effector cell–associated neurotoxicity syndrome occurred in 6.4% of patients with one fatal event. CONCLUSION Subcutaneous epcoritamab resulted in deep and durable responses and manageable safety in highly refractory patients with large B-cell lymphoma, including those with prior CAR T-cell exposure.

The COVID-19 pandemic poses a unique challenge to the care of patients with haematological malignancies.

The phase II CAVALLI (NCT02055820) study assessed efficacy and safety of venetoclax, a selective, B-cell lymphoma-2 (Bcl-2) inhibitor, with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in first-line (1L) diffuse large B-cell lymphoma (DLBCL), including patients demonstrating Bcl-2 protein overexpression by immunohistochemistry (Bcl-2 IHC-positive). Eligible patients ≥18 years with previously untreated DLBCL, Eastern Cooperative Oncology Group performance status ≤2, and International Prognostic Index 2-5. Venetoclax 800 mg (days 4-10, cycle 1 and days 1-10, cycles 2-8) was administered with rituximab (8 cycles) and CHOP (6-8 cycles); 21-day cycles. Primary endpoints: safety, tolerability, and complete response (CR) at end of treatment (EOT). Secondary endpoints: progression-free survival (PFS) and overall survival. Comparative analyses used covariate-adjusted R-CHOP controls from the GOYA/BO21005 study, an appropriate contemporary benchmark for safety and efficacy. Safety and efficacy analyses included 206 patients. CR rate at EOT was 69% in the overall population and was maintained across Bcl-2 IHC-positive subgroups. With median follow-up of 32.2 months, trends were observed for improved investigator-assessed PFS for venetoclax plus R-CHOP in the overall population (Hazard ratio [HR] = 0.61, 95% confidence interval [CI], 0.43-0.87) and Bcl-2 IHC-positive subgroups (HR = 0.55, 95% CI, 0.34-0.89), versus R-CHOP. Despite a higher incidence of grade 3/4 hematologic adverse events (86%), related mortality was not increased (2%). Chemotherapy dose intensity was similar in CAVALLI versus GOYA. The addition of venetoclax to R-CHOP in 1L DLBCL demonstrates increased but manageable myelosuppression and the potential of improved efficacy particularly in high-risk, Bcl-2 IHC-positive patient subgroups.

SummaryNovel therapies with increased efficacy and decreased toxicity are desperately needed for the treatment of acute myeloid leukaemia (AML). The anti CD33 immunoconjugate, gemtuzumab ozogamicin (GO), was withdrawn with concerns over induction mortality and lack of efficacy. However a number of recent trials suggest that, particularly in AML with favourable cytogenetics, GO may improve overall survival. This data and the development of alternative novel monoclonal antibodies (mAb) have renewed interest in the area. Leukaemic stem cells (LSC) are identified as the subset of AML blasts that reproduces the leukaemic phenotype upon transplantation into immunosuppressed mice. AML relapse may be caused by chemoresistant LSC and this has refocused interest on identifying and targeting antigens specific for LSC. Several mAb have been developed that target LSC effectively in xenogeneic models but only a few have begun clinical evaluation. Antibody engineering may improve the activity of potential new therapeutics for AML. The encouraging results seen with bispecific T cell-engaging mAb-based molecules against CD19 in the treatment of B-cell acute lymphobalstic leukaemia, highlight the potential efficacy of engineered antibodies in the treatment of acute leukaemia. Potent engineered mAb, possibly targeting novel LSC antigens, offer hope for improving the current poor prognosis for AML.

Summary De novo diffuse large B‐cell lymphoma (DLBCL) presenting with synchronous central nervous system (CNS) and systemic disease (synDLBCL) is not well described and is excluded from clinical trials. We performed a retrospective analysis of 80 synDLBCL patients treated across 10 Australian and UK centres. Of these patients, 96% had extranodal systemic disease. CNS‐directed treatment with combination intravenous cytarabine and high‐dose methotrexate (“CNS‐intensive”) (n = 38) was associated with favourable survival outcomes compared with “CNS‐conservative” strategies such as intravenous high‐dose methotrexate monotherapy, intrathecal therapy and/or radiotherapy (2‐year progression‐free survival [PFS] 50% vs. 31%, P = 0·006; 2‐year overall survival [OS] 54% vs. 44%, P = 0·037). Outcomes were primarily dictated by the ability to control the CNS disease, with 2‐year cumulative CNS relapse incidence of 42% and non‐CNS relapse 21%. Two‐year OS for CNS‐relapse patients was 13% vs. 36% for non‐CNS relapses (P = 0·02). Autologous stem cell transplantation as consolidation (n = 14) was not observed to improve survival in those patients who received CNS‐intensive induction when matched for induction outcomes (2‐year PFS 69% vs. 56%, P = 0·99; 2‐year OS 66% vs. 56%, P = 0·98). Hyperfractionated or infusional systemic treatment did not improve survival compared to R‐CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone) (2‐year OS 49% for both groups). Our study suggests that adequate control of the CNS disease is paramount and is best achieved by intensive CNS‐directed induction.

Only modest advances in AML therapy have occurred in the past decade and relapse due to residual disease remains the major challenge. The potential of the immune system to address this is evident in the success of allogeneic transplantation, however this leads to considerable morbidity. Dendritic cell (DC) vaccination can generate leukemia-specific autologous immunity with little toxicity. Promising results have been achieved with vaccines developed from purified monocytes (Mo-DC). We now demonstrate that blood DC (BDC) have superior function to Mo-DC. Whilst BDC are reduced at diagnosis in AML, they recover following chemotherapy and allogeneic transplantation, can be purified using CMRF-56 antibody technology, and can stimulate functional T cell responses. While most AML patients in remission had a relatively normal T cell landscape, those who had received fludarabine as salvage therapy have persistent T cell abnormalities including reduced number, altered subset distribution, failure to expand, and increased activation-induced cell death. Furthermore, PD-1 and TIM-3 are increased on CD4T cells in AML patients in remission and their blockade enhances the expansion of leukemia-specific T cells. This confirms the feasibility of a BDC vaccine to consolidate remission in AML and suggests it should be tested in conjunction with checkpoint blockade.

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