B-cell non-Hodgkin lymphoid malignancies (NHLs) are defined by clonal populations of B- lymphocytes. JNJ-80948543 is a T-cell redirecting tri-specific antibody that recognizes the cluster of differentiation 3 (CD3) antigen on T lymphocytes and CD79b, and CD20 surface antigens on mature healthy and malignant B- lymphocytes. The study will be conducted in 2 parts: Part A (dose Escalation) and part B (Cohort Expansion). Each of the 2 parts of this study is divided into 3 periods, a screening phase, a treatment phase and a post-treatment follow-up phase. The total duration of the study will be up to 2 year 5 months. Efficacy assessments will include radiographic image assessments, positron emission tomography scan, bone marrow assessment, endoscopy, physical examinations. Safety will be monitored throughout the study.
The purpose of this study is to characterize safety and to determine the putative recommended Phase 2 dose(s) (RP2D[s]) and optimal dosing schedule(s) of JNJ-80948543 in Part A (Dose Escalation) and to further characterize the safety of JNJ-80948543 at the putative RP2D(s) in Part B (Cohort Expansion).