A Study to Learn How Safe and Tolerable Odronextamab and Cemiplimab Are in Adult Patients With B-cell Malignancies

Key Inclusion Criteria:

• Have documented CD20+ aggressive B-cell NHL that is either not responsive to or relapsed after at least 2 prior lines of systemic therapy, for whom treatment with an anti-CD20 antibody may be appropriate. In addition, prior treatments should at least contain an anti-CD20 antibody and an alkylating agent.
• Must have at least 1 nodal lesion (≥1.5 cm), or at least one extranodal lesion with longest transverse diameter (LDi) greater than 1.0 cm, documented by diagnostic imaging (computed tomography [CT] or magnetic resonance imaging [MRI]).
• Eastern Cooperative Oncology Group (ECOG) performance status ≤1
• Adequate bone marrow and hepatic function, as defined in the protocol
• Willing and able to comply with clinic visits and study-related procedures
• Provide signed informed consent

Key Exclusion Criteria:

• Primary central nervous system (CNS) lymphoma, or known or suspected CNS involvement by non-primary CNS NHL
• History of or current relevant CNS pathology, as described in the protocol
• Ongoing or recent (within 2 years) evidence of significant autoimmune disease that required treatment with systemic immunosuppressive treatments, which may suggest risk for immune-mediated adverse events (iAEs)
• Prior therapies, as described in the protocol
• Uncontrolled infection with human immunodeficiency virus (HIV), hepatitis B or hepatitis C infection or other uncontrolled infection
• Cytomegalovirus infection as noted by detectable levels on peripheral blood polymerase chain reaction (PCR) assay until the infection is well controlled.
• Known hypersensitivity to both allopurinol and rasburicase
• Pregnant or breastfeeding women
• Women of childbearing potential, or men who are unwilling to practice highly effective contraception prior to the initial dose/start of the first treatment, during the study, and for at least 6 months after the last dose, as defined in the protocol
• Patients prior diagnosis of hemophagocytic lymphohistiocytosis (HLH) or macrophage activation syndrome (MAS)

Note: Other protocol-defined Inclusion/Exclusion criteria apply