A Phase 3 Trial of Epcoritamab vs Investigator's Choice Chemotherapy in Relapsed/Refractory (R/R) Diffuse Large B-cell Lymphoma (DLBCL)

Main Inclusion Criteria:

1. Relapsed or refractory disease and previously treated with at least 1 line ofsystemic antineoplastic therapy including anti-CD20 monoclonal antibody (mAb)-containing combination chemotherapy since lymphoma diagnosis

2. One of the confirmed histologies below with CD20-positivity:

3. DLBCL, not otherwise specified (NOS), including de novo or histologicallytransformed from follicular lymphoma (FL)

4. "Double-hit" or "triple-hit" DLBCL (technically classified in World HealthOrganization (WHO) 2016 as high-grade B-cell lymphoma (HGBCL), with MYC andBCL2 and/or BCL6 translocations), including de novo or histologicallytransformed from FL

5. FL Grade 3B

6. T-cell/histiocyte-rich large B-cell lymphoma

7. Eastern Cooperative Oncology Group Performance Status (ECOG PS) score of 0-2

8. Failed previous HDT-ASCT or not eligible for high-dose therapy autologous stem celltransplant (HDT-ASCT) at screening

9. Participants must have detectable disease by positron emission tomography (PET) scanand measurable by computed tomography (CT) scan or magnetic resonance imaging (MRI)

10. Acceptable renal and liver function

11. Life expectancy >2 months on standard of care treatment

Main Exclusion Criteria:

1. Primary Central Nervous System (CNS) tumor or known CNS involvement

2. Any prior therapy with a bispecific antibody targeting CD3 and CD20

3. Major surgery within 4 weeks prior to randomization

4. Chemotherapy and other non-investigational antineoplastic agents (except CD20 mAbs)within 4 weeks or 5 half-lives (whichever is shorter) prior to randomization

5. Any investigational drug within 4 weeks or 5 half-lives, whichever is longer, priorto randomization

6. Autologous stem cell transplant (ASCT) within 100 days of randomization

7. Treatment with chimeric antigen receptor T-cell (CAR-T) therapy within 100 daysprior to randomization

8. Seizure disorder requiring anti-epileptic therapy

9. Clinically significant cardiac disease