• Biopsy proven B-NHL, including DLBCL, HGBL, or FL.

• Relapsed/refractory cohorts:

⁃ In order to be eligible subjects must have received at least 2 prior lines of therapy and not be candidates for treatment regimens known to provide clinical benefit in B-NHL. CAR T-naive subjects are allowed if they have declined, are considered ineligible for, or do not have timely access to CAR T cell therapies.

• 1L FL cohorts: Subject has biopsy-proven FL Grade 1-3a per WHO 2016 classification, Stage II-IV, FL International Prognostic Index 2-5 that has not been treated with prior systemic lymphoma-directed therapy and requires initiation of treatment based on GELF criteria. Radiation to localized disease prior to study entry is allowed if \>14 days from first dose.

• All Cohorts:

⁃ Subject has an Eastern Cooperative Oncology Group (ECOG) Performance Status of ≤ 2.

• Subject must have adequate liver, bone marrow and kidney function (eGFR ≥ 50 mL/min).

• Subject must have locally confirmed CD19 positivity (must be documented after time of progression from last CD19-targeted therapy, if received)

• Subject must have at least 1 measurable disease site

• Subject must have ANC \>/= 1000/mm3, platelets \>/= 50,000 mm3, hemoglobin \>/= 8.0 g/dL. Transfusion and/or growth factor are allowed but counts must be stable for at least 72 hours afterwards prior to screening

• Subject must have a total bilirubin \<1.5x ULN, AST/ALT \< 3xULN