The purpose of this study is to evaluate the preliminary efficacy, safety, and pharmacokinetics of glofitamab (glofit) in combination with rituximab plus ifosfamide, carboplatin, and etoposide (R-ICE) in participants with relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL), who have failed one prior line of therapy incorporating an anti-cluster of differentiation (CD) 20 antibody (i.e., rituximab) and an anthracycline, and who are transplant or chimeric antigen receptor T-cell (CAR-T) therapy eligible, defined as being medically eligible for intensive platinum-based salvage therapy followed by autologous stem cell transplantation (ASCT) or for CAR-T therapy.

Inclusion Criteria:

• Life expectancy ≥ 12 weeks
• Histologically confirmed B-cell lymphoma
• One line of prior systemic therapy including an anti-CD20 monoclonal antibody (i.e. rituximab) and an anthracycline
• Relapsed or refractory disease after first-line chemoimmunotherapy
• Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1
• Participant must be a candidate for high-dose chemotherapy followed by ASCT or CAR-T therapy

Exclusion Criteria:

• Treatment with more than one prior line of therapy for DLBCL
• Primary mediastinal B-cell lymphoma
• Prior treatment with glofitamab or other bispecific antibodies targeting both CD20 and CD3
• Peripheral neuropathy assessed to be Grade > 1 according to National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) v5.0 at enrollment
• Treatment with radiotherapy, chemotherapy, immunotherapy, immunosuppressive therapy, or any investigational agent for the purposes of treating cancer within 2 weeks prior to first study treatment
• Treatment with monoclonal antibodies for the purposes of treating cancer within 4 weeks prior to first study treatment
• Primary or secondary CNS lymphoma at the time of enrollment or history of CNS lymphoma
• Current or history of CNS disease, such as stroke, epilepsy, CNS vasculitis, or neurodegenerative disease
• Known or suspected history of hemophagocytic lymphohistiocytosis (HLH)
• Known history of progressive multifocal leukoencephalopathy
• Adverse events from prior anti-cancer therapy that have not resolved to Grade 1 or better (with the exception of alopecia and anorexia, or as otherwise permitted by inclusion criteria)
• Prior solid organ transplantation
• Prior allogeneic stem cell transplant
• Prior ASCT for lymphoma
• Prior autologous stem cell transplant for any indication other than lymphoma, within 5 years from the start of study treatment
• Active autoimmune disease requiring treatment
• Prior treatment with systemic immunosuppressive medications (including, but not limited to, cyclophosphamide, azathioprine, methotrexate, thalidomide, and anti-tumor necrosis factor agents), within 4 weeks prior to first dose of study treatment
• Ongoing corticosteroid use > 30 mg/day of prednisone or equivalent. Participants who received corticosteroid treatment with ≤ 30 mg/day of prednisone or equivalent must be documented to be on a stable dose of at least 4 weeks' duration prior to Cycle 1 Day 1. Participants may have received a brief (≤ 7 days) course of systemic steroids (≤ 100 mg prednisone equivalent per day) prior to initiation of study therapy for control of lymphoma-related symptoms
• Recent major surgery (within 4 weeks before the first study treatment) other than for diagnosis
• Clinically significant history of cirrhotic liver disease