This is a Phase 1/2, multi-center, open-label study evaluating the safety and efficacy of rondecabtagene autoleucel (ronde-cel) also known as LYL314, a dual-targeting chimeric antigen receptor (CAR) targeting cluster of differentiation (CD)19 and CD20 in participants with aggressive large B-cell lymphoma.

The goal of this clinical study is to learn more about the safety and effectiveness of the study drugs, KITE-363 and KITE-753, in participants with relapsed and/or refractory B-cell lymphoma.

This is a randomized, open-label study in adult patients who have completed standard first line therapy for large B-cell lymphoma (LBCL) and achieved a complete response or partial response suitable for observation, but who have minimal residual disease (MRD) as detected by the Foresight CLARITY Investigational Use Only (IUO) MRD test, powered by PhasED-Seq. The purpose of the trial is to assess the efficacy and safety of consolidation with cemacabtagene ansegedleucel (cema-cel), an allogeneic CD19 CAR T product, as compared to standard of care observation.

In this study, participants with MRD are randomized 1:1 to treatment with cema-cel or an observation arm. Treatment includes cema-cel following a lymphodepletion regimen of fludarabine and cyclophosphamide.

Prior to August 2025, participants may also have received an anti-CD52 monoclonal antibody, ALLO-647, as part of their lymphodepletion regimen.

This study is researching an experimental drug called odronextamab, referred to as study drug. The study is focused on participants with previously untreated follicular lymphoma (a type of non-Hodgkin lymphoma or NHL).

This study will be made up of two parts: Part 1 (non-randomized) and Part 2 (randomized - controlled).

The aim of Part 1 of the study is to see how safe and tolerable the study drug is when given alone.

The aim of Part 2 of the study is to see how the study drug works compared to rituximab (called the "comparator drug") and chemotherapy (the current standard of care for NHL). Standard of care means the usual medication expected and used when receiving treatment for a condition.

The study is looking at several other research questions, including:

* What side effects may happen from taking the study drug
* How much study drug is in the blood at different times
* Whether the body makes antibodies against the study drug (which could make the study drug less effective or could lead to side effects)
* How the study drug affects quality of life and ability to complete routine daily activities.

The purpose of this study is to assess Tacrolimus/Methotrexate/Ruxolitinib versus Post-Transplant Cyclophosphamide/Tacrolimus/Mycophenolate Mofetil in Non-Myeloablative/Reduced Intensity Conditioning Allogeneic Peripheral Blood Stem Cell Transplantation