A Phase 3 Study of Tabelecleucel for Participants With Epstein-Barr Virus-Associated Post-Transplant Lymphoproliferative Disease After Failure With Rituximab or Rituximab and Chemotherapy

Inclusion Criteria:

1. Prior SOT of kidney, liver, heart, lung, pancreas, small bowel, or any combinationof these (C-SOT); or prior allogeneic HCT (C-HCT).

2. A diagnosis of locally assessed, biopsy-proven EBV+ PTLD.

3. Availability of appropriate partially HLA-matched and restricted tabelecleucel hasbeen confirmed by the sponsor.

4. Measurable, 18F-deoxyglucose (FDG)-avid (Deauville score ≥ 3) systemic disease usingLugano Classification response criteria by positron emission tomography (PET)-diagnostic computed tomography (CT), except when contraindicated or mandatedby local practice, then magnetic resonance imaging (MRI) may be used. Forparticipants with treated central nervous system (CNS) disease, a head CT and/orbrain/spinal MRI as clinically appropriate will be required to follow CNS diseaseresponse per Lugano Classification response criteria.

5. Treatment failure of rituximab or interchangeable commercially available biosimilarmonotherapy (C-SOT-R or C-HCT) or rituximab plus any concurrent or sequentiallyadministered chemotherapy regimen (C-SOT-R+C) for treatment of PTLD.

6. Males and females of any age.

7. Eastern Cooperative Oncology Group performance status ≤ 3 for participants aged ≥ 16years; Lansky score ≥ 20 for participants < 16 years.

8. For C-HCT only: If allogeneic HCT was performed as treatment for an acute lymphoidor myeloid malignancy, the underlying primary disease for which the participantunderwent transplant must be in morphologic remission.

9. Adequate organ function.

10. Absolute neutrophil count ≥ 1000/μL, (C-SOT) or ≥ 500/μL (C-HCT), with orwithout cytokine support.

11. Platelet count ≥ 50,000/μL, with or without transfusion or cytokine support.For C-HCT, platelet count < 50,000/μL but ≥ 20,000/μL, with or withouttransfusion support, is permissible if the participant has not had grade ≥ 2bleeding in the prior 4 weeks (where grading of the bleeding is determined perthe National Cancer Institute's Common Terminology Criteria for Adverse Events [CTCAE], version 5.0).

12. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and totalbilirubin each < 5 × the upper limit of normal; however, ALT, AST, and totalbilirubin each ≤ 10 × upper limit of normal is acceptable if the elevation isconsidered by the investigator to be due to EBV and/or PTLD involvement of theliver as long as there is no known evidence of significant liver dysfunction.

13. Participant or participant's representative is willing and able to provide writteninformed consent.

Exclusion Criteria:

1. Currently active Burkitt, T-cell, NK/T-cell lymphoma/LPD, Hodgkin, plasmablastic,transformed lymphoma, active hemophagocytic lymphohistiocytosis, or othermalignancies requiring systemic therapy.

2. Daily steroids of > 0.5 mg/kg prednisone or glucocorticoid equivalent, ongoingmethotrexate, or extracorporeal photopheresis.

3. Untreated CNS PTLD or CNS PTLD for which the participant is actively receivingCNS-directed chemotherapy (systemic or intrathecal) or radiotherapy at enrollment.NOTE: Participants with previously treated CNS PTLD may enroll if CNS-directedtherapy is complete.

4. Suspected or confirmed grade ≥ 2 graft-versus-host disease (GvHD) per the Center forInternational Blood and Marrow Transplant Research consensus grading system atenrollment.

5. Ongoing or recent use of a checkpoint inhibitor agent (eg, ipilimumab,pembrolizumab, nivolumab) within 3 drug half-lives from the most recent dose toenrollment.

6. For C-HCT: active adenovirus viremia.

7. Need for vasopressor or ventilatory support.

8. Antithymocyte globulin or similar anti-T cell antibody therapy ≤ 4 weeks prior toenrollment.

9. Treatment with Epstein-Barr virus cytotoxic T lymphocytes or chimeric antigenreceptor T cells directed against B cells within 8 weeks of enrollment (C-SOT orC-HCT), or unselected donor lymphocyte infusion within 8 weeks of enrollment (C-HCTonly).

10. Female who is breastfeeding or pregnant or female of childbearing potential or malewith a female partner of childbearing potential unwilling to use a highly effectivemethod of contraception.

11. Inability to comply with study-related procedures.

12. Any medical condition or organ system dysfunction that in the investigator';sopinion, could compromise the participant's safety or ability to complete the study.