This study is researching an experimental drug called REGN5837 in combination with another drug, odronextamab (called "study drug\[s\]"), in patients with relapsed or refractory aggressive B-cell Non-Hodgkin Lymphomas (B-NHLs).
The study has 2 parts. The aim of the first part (dose escalation) is to find a safe dose of REGN5837 when given in combination with odronextamab.
The goal of the second part (dose expansion) is to use the REGN5837 drug dose found in the first part to see how well REGN5837 in combination with odronextamab works.
The study is looking at several other research questions, including:
* What side effects may happen from taking the study drugs * How much study drug is in the blood at different times * Whether the body makes antibodies against the study drugs (that could make the drugs less effective or could lead to side effects)
Have documented CD20+ aggressive B-NHL, with disease that has progressed after at least 2 lines of systemic therapy containing an anti-CD20 antibody and an alkylating agent, as described in the protocol.
Measurable disease on cross sectional imaging as defined in the protocol
Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1
Adequate bone marrow, renal and hepatic function as defined in the protocol
Prior treatments with allogeneic stem cell transplantation or solid organ transplantation, treatment with anti-CD20 x anti- CD3 bispecific antibody, such as odronextamab
Diagnosis of Mantle Cell Lymphoma (MCL)
Primary Central Nervous System (CNS) lymphoma or known involvement by non-primary CNS lymphoma, as described in the protocol
Treatment with any systemic anti-lymphoma therapy within 5 half-lives or within 14 days prior to first administration of study drug, whichever is shorter, as described in the protocol