The goal of this clinical trial is to evaluate clinical efficacy of incorporating Epcoritamab into the salvage treatment routine for relapsed-refractory aggressive B-cell lymphoma, followed by autologous stem-cell transplantation (ASCT) and consolidation Epcoritamab. The main questions it aims to answer are:
* Will the addition of epcoritamab to intensive salvage chemotherapy be safe and increase the proportion of patients with relapsed or refractory (R/R) large B-cell lymphoma who achieve a complete remission prior to planned transplant?
* Is consolidation epcoritamab after ASCT deliverable and safe?
* Will consolidation epcoritamab will result in improved clearance of molecularly detectable residual disease?
* Will the combination of pre- and post-ASCT epcoritamab lead to higher rates of progression-free survival (PFS) and event free survival (EFS) at 12 months compared to historical estimates in this population.
Participants will undergo three phases in this trial:
1. Epcoritamab-Salvage treatment: consists of 3 cycles of R-DHAOx (rituximab, dexamethasone, cytarabine, oxaliplatin) plus Epcoritamab
2. ASCT: Pre-autograft eligibility assessment for ASCT will be performed according to local practice. ASCT may be administered at local referring centre and will follow local standard operative procedures.
3. Consolidation treatment: consists of six 28-day cycles of subcutaneous Epcoritamab, commencing 6 - 12 weeks post ASCT.