Inclusion Criteria:

          -  Participants with relapsed or refractory diffuse and transformed large B-cell lymphoma
             (R/R DLBCL). DLBCL and cell of origin (GCB versus non-GCB) will be histologically
             determined by local pathology assessment for the purposes of study eligibility and
             stratification.

          -  Participants must have R/R disease following 2 or more lines of prior systemic
             therapy.

          -  Participants must be HSCT or CAR-T ineligible according to the investigator and must
             meet at least one of the following criteria:

               1. One or more co-morbidities, including cardiac, pulmonary, renal or hepatic
                  dysfunction that in the opinion of the Investigator make the subject medically
                  unfit to received HSCT or CAR-T therapy

               2. Active disease following induction and salvage chemotherapy

               3. Inadequate stem cell mobilization (for HSCT)

               4. Relapse following prior HSCT or CAR-T

               5. Unable to receive CAR-T therapy due to financial, geographic, insurance, or
                  manufacturing issues

          -  Participants will need to have a formalin-fixed paraffin-embedded tumor tissue
             (obtained ≤4 weeks before Day 1) submitted to the central pathology lab.

          -  An Eastern Cooperative Oncology Group (ECOG) performance status score of 0 to 2

          -  Participants must have fluorodeoxyglucose (FDG)-avid disease by positron emission
             tomography (PET) and bidimensional measurable disease of at least 1.5 cm by computed
             tomography (CT), as assessed by the site radiologist within 28 days of Day 1.

        Exclusion Criteria:

          -  History of another malignancy within 2 years before the first dose of study drug or
             any evidence of residual disease from a previously diagnosed malignancy

          -  History of progressive multifocal leukoencephalopathy (PML)

          -  Active cerebral/meningeal disease related to the underlying malignancy. Subjects with
             a history of cerebral/meningeal disease related to the underlying malignancy are
             allowed if prior CNS disease has been effectively treated and without progression for
             at least 3 months.

          -  Any uncontrolled Grade 3 or higher (per NCI CTCAE version 5.0) viral, bacterial, or
             fungal infection within 2 weeks prior to the first dose of study drug. Routine
             antimicrobial prophylaxis is permitted

          -  Chemotherapy, radiotherapy, biologics, and/or other antitumor treatment with
             immunotherapy that is not completed 3 weeks prior to first dose of study drug, unless
             underlying disease has progressed on treatment

          -  Current therapy with immunosuppressive medications (including steroids), other
             systemic anti-neoplastic, or investigational agents

             a) Prednisone (or equivalent) ≤10 mg/day may be used for non-lymphomatous purposes

          -  Documented history of a cerebral vascular event (stroke or transient ischemic attack),
             unstable angina, myocardial infarction, or cardiac symptoms consistent with New York
             Heart Association (NYHA) Class III-IV within 6 months prior to the first dose of study
             drugs

          -  Congestive heart failure, Class III or IV, by the NYHA criteria

          -  Grade 2 or higher peripheral sensory or motor neuropathy at baseline