Inclusion Criteria:

   1. Confirmed DLBCL as per the local histopathological assessment.

   2. Relapsed or refractory disease having received 2 or more lines of systemic therapy,
   including anti-CD20 and anthracycline based chemotherapy, and either having progressed
   after (or relapsed after) ASCT, or being ineligible for or not consenting to ASCT.

   3. Measurable disease at time of enrollment.

   4. Eastern Cooperative Oncology Group (ECOG) performance status that is either 0 or 1 at
   screening.

   5. Adequate renal, liver, and bone marrow, organ function, and minimum level of pulmonary
   reserve.

Exclusion Criteria:

   1. Patients with Richter's transformation, Burkitt's lymphoma, and primary DLBCL of the
   CNS.

   2. Prior anti-CD19 directed therapy.

   3. Prior gene therapy.

   4. Prior adoptive T cell therapy.

   5. Prior ibrutinib therapy within the 30 days prior to screening.

   6. Patients with active CNS involvement are excluded, except if the CNS involvement has
   been effectively treated and provided that local treatment was > 4 weeks before
   enrollment.

   7. Prior allogeneic HSCT

   8. . Significant cardiac abnormality including history of myocardial infarction within 6
   months prior to screening as detailed in the study protocol.

Other eligibility criteria may apply.