A Study to Evaluate the Optimization of the Cytokine Release Syndrome Profile for Glofitamab in Combination With Gemcitabine Plus Oxaliplatin in Participants With Relapsed/Refractory Aggressive B-Cell Non-Hodgkin's Lymphoma

Inclusion Criteria:

• Histologically confirmed large B-cell lymphoma (de novo or transformed from FL) withone of the following diagnoses according to World Health Organization, fifthedition: DLBCL Not Otherwise Specified (NOS); High-Grade B-Cell Lymphoma (HGBL),NOS; DLBCL/HGBL with MYC and BCL2 rearrangements

• R/R disease, defined as: relapsed = disease that has recurred following a responsethat lasted >/= 6 months after completion of the last line of therapy; refractory =disease that did not respond to or that progressed < 6 months after completion ofthe last line of therapy

• At least one line of prior systemic therapy

• Participants who have failed only one prior line of therapy must not be a candidatefor high-dose chemotherapy followed by autologous stem cell transplant (ASCT)

• At least one bi-dimensionally measurable (> 1.5 cm) nodal lesion, or onebi-dimensionally measurable (> 1 cm) extranodal lesion, as measured on CT scan

• Eastern Cooperative Oncology Group (ECOG) status of 0, 1, or 2

• According to the investigator's judgment, participants should be able to receive thestep-up dose regimen in an outpatient setting

• Adequate hematologic and renal function

Exclusion Criteria:

• Prior enrollment in Studies GO41943 (NCT04313608), GO41944 (STARGLO; NCT04408638),or Study GO44900 (NCT06624085)

• Participant has failed only one prior line of therapy and is a candidate for stemcell transplantation

• Any history of Waldenstrom's macroglobulinemia

• Primary mediastinal B-cell lymphoma

• History of severe allergic or anaphylactic reactions to humanized or murinemonoclonal antibodies (or recombinant antibody-related fusion proteins) or knownsensitivity or allergy to murine products

• Contraindication to obinutuzumab, gemcitabine or oxaliplatin, or tocilizumab

• Prior treatment with glofitamab or other bispecific antibodies targeting both CD20and CD3

• Prior treatment with gemcitabine or oxaliplatin

• Peripheral neuropathy or paresthesia assessed to be Grade >/= 2 according to theNational 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 weeksprior to first study treatment

• Treatment with monoclonal antibodies for the purposes of treating cancer within 4weeks prior to first study treatment

• Primary or secondary CNS lymphoma at the time of recruitment

• Prior CNS involvement that has been definitively treated and confirmed via magneticresonance imaging (MRI) or cerebrospinal fluid analysis to be in complete remissionis permissible

• Current or history of CNS disease, such as stroke, epilepsy, CNS vasculitis, orneurodegenerative disease

• History of other primary malignancy, with exceptions defined by the protocol

• Significant or extensive cardiovascular disease

• Significant pulmonary disease (including moderate or severe obstructive pulmonarydisease)

• Known active bacterial, viral, fungal, mycobacterial, parasitic, or other infection (excluding fungal infections of nail beds) at study enrollment or any major episodeof infection (as evaluated by the investigator) within 4 weeks prior to the firststudy treatment

• Positive for: severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2);tuberculosis; hepatitis B virus (HBV); hepatitis C virus (HCV); chronic activeEpstein-Barr viral infection

• Known or suspected history of hemophagocytic lymphohistiocytosis (HLH) orprogressive multifocal leukoencephalopathy

• Adverse events from prior anti-cancer therapy that have not resolved to Grade 1 orbetter (with the exception of alopecia and anorexia)

• Administration of a live, attenuated vaccine within 4 weeks before first studytreatment administration or anticipation that such a live, attenuated vaccine willbe required during the study

• Prior solid organ transplantation or prior allogenic stem cell transplant

• Active autoimmune disease requiring treatment

• Prior treatment with systemic immunosuppressive medications (including, but notlimited to, cyclophosphamide, azathioprine, methotrexate, thalidomide, and antitumornecrosis factor agents), within 4 weeks prior to first dose of study treatment

• Ongoing systemic corticosteroid use which, in the opinion of the investigator, putsthe participant at increased risk of steroid-related iatrogenic adrenalinsufficiency

• Recent major surgery (within 4 weeks before the first study treatment) other thanfor diagnosis

• Clinically significant history of cirrhotic liver disease

• Any other diseases, metabolic dysfunction, physical examination finding, or clinicallaboratory finding giving reasonable suspicion of a disease or condition thatcontraindicates the use of an investigational drug or that may affect theinterpretation of the results or renders the participant at high-risk from treatmentcomplications

• Pregnancy or breastfeeding, or intention of becoming pregnant during the study orwithin 18 months after the final dose of study treatment