Tabelecleucel for Allogeneic Hematopoietic Cell Transplant Subjects With Epstein-Barr Virus-Associated Post-Transplant Lymphoproliferative Disease (EBV+ PTLD) After Failure of Rituximab

This is a multicenter, open label, single-arm, phase 3 study to assess the efficacy and
safety of tabelecleucel for the treatment of EBV+ PTLD in the setting of allogeneic HCT after
failure of rituximab.

Tabelecleucel will be selected for the subject from the bank of available tabelecleucel cell
products based on matching >= 2 human leukocyte antigen (HLA) alleles, at least one of which
is a restricting HLA allele, shared between the tabelecleucel donor and the subject's EBV+
PTLD. Sites will provide high resolution subject and subject's graft donor HLA typing results
and other information as required by the protocol.

Tabelecleucel will be administered in cycles lasting 5 weeks (35 days). During each cycle,
subjects will receive intravenous (IV) tabelecleucel at a dose of 2×10^6 cells/kg on Days 1,
8, and 15, followed by observation through Day 35.

Inclusion Criteria:

1. Prior allogeneic hematopoietic cell transplant

2. A diagnosis of locally-assessed, biopsy-proven EBV+ PTLD with a pathology sample
available for central review

3. Availability of appropriate partially HLA-matched and restricted tabelecleucel cell
product

4. Measurable, 18F-deoxyglucose (FDG)-avid (Deauville score >= 3) systemic disease (using
Lugano Classification response criteria) by positron emission tomography
(PET)-diagnostic computed tomography (CT). Baseline scans must be of acceptable
quality to the central radiology laboratory prior to Cycle 1 Day 1.

5. Failure of rituximab for first-line treatment of PTLD. Note: Subjects with CD20
negative disease are eligible to enroll without prior anti-CD20 therapy after failure
of first-line treatment (reduction of immunosuppression is not considered first-line
therapy) and discussion with the sponsor's medical monitor.

6. Males and females of any age

7. Eastern Cooperative Oncology Group (ECOG) performance status <= 3 for subjects aged >
16 years; Lansky score >= 20 for subjects from birth to 16 years

8. Underlying primary disease, for which the subject underwent transplant, is in
morphologic remission

9. Adequate organ function

1. Absolute neutrophil count >= 500/µL, with or without cytokine support

2. Platelet count >= 50,000/µL, with or without transfusion support; platelet count
< 50,000/µL but >= 20,000/µL, with or without transfusion support, is permissible
if the subject has not had Grade >= 2 bleeding in the prior 6 months (where
grading of the bleeding is determined per the National Cancer Institute's Common
Terminology Criteria for Adverse Events [CTCAE], version 5.0)

3. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total
bilirubin (TBILI) each < 3 x the upper limit of normal (ULN); however, ALT, AST,
and TBILI each <= 5 x ULN is acceptable if the elevation is considered by the
investigator to be due to PTLD involvement of the liver

4. Creatinine < 3 x ULN

10. Subject or subject's representative is willing and able to provide written informed
consent

Exclusion Criteria:

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

2. History of central nervous system (CNS) PTLD

3. Grade >= 2 graft-versus-host disease (GvHD) per the Center for International Blood and
Marrow Transplant Research (CIBMTR) consensus grading system at enrollment

4. Ongoing or recent use of a checkpoint inhibitor (eg, nivolumab, pembrolizumab,
ipilimumab) within three drug half-lives from the most recent dose to Cycle 1 Day 1

5. Active adenovirus viremia

6. Need for vasopressor or ventilatory support

7. Antithymocyte globulin or similar anti-T cell antibody therapy <= 4 weeks prior to
Cycle 1 Day 1

8. Treatment with Epstein-Barr virus cytotoxic T lymphocytes, chimeric antigen receptor
(CAR)-T cells directed against B cells, or unselected donor lymphocyte infusion (DLI)
within 8 weeks of Cycle 1 Day 1

9. Pregnancy

10. Female of childbearing potential or male with a female partner of childbearing
potential unwilling to use a highly effective method of contraception

11. Inability to comply with study-related procedures