This is a multicenter, multicohort, open label, single-arm, Phase 2 study to assess the efficacy and safety of tabelecleucel for the treatment of EBV-associated diseases in participants who are newly diagnosed or relapsed/refractory to prior treatment. Newly diagnosed or relapsed/refractory participants will be enrolled in one of the following cohorts:~EBV+ lymphoproliferative disease (LPD) in the setting of primary immunodeficiency (PID) (PID LPD)~EBV+ LPD in the setting of acquired (non-congenital) immunodeficiency (AID) (AID LPD)~EBV+ posttransplant lymphoproliferative disorder involving the central nervous system (CNS PTLD)~EBV+ PTLD where standard first line therapy (rituximab or chemotherapy) is not appropriate, including CD20 negative disease~EBV+ sarcomas, including leiomyosarcoma (LMS)~Chronic active EBV (CAEBV) and EBV+ hemophagocytic lymphohistiocytosis (HLH) (CAEBV/HLH cohort)~Tabelecleucel will be administered in cycles lasting for 35 days. During each cycle, participants will receive tabelecleucel at a dose of 2 x 10^6 cells/kg intravenously (IV) weekly for 3 weeks, followed by observation through Day 35. Treatment will continue until maximal disease progression, unacceptable toxicity, or initiation of nonprotocol therapy for the underlying disease. For EBV+ sarcoma cohort, treatment will continue until disease progression, unacceptable toxicity, or up to 24 months from first dose. Participants who fail to respond to initial tabelecleucel treatment may continue tabelecleucel with a different human leukocyte antigen (HLA) restriction (termed a Restriction Switch), if available; administration of tabelecleucel with up to 4 different HLA restrictions is allowed for any participant.~Participants will complete a safety follow-up visit at 30 days after the last dose. Participants without documented disease progression will be assessed every 3 months after the safety follow-up visit for continued evaluation of disease response until the end of study (EOS) visit at 24-month after first dose. Participants with disease progression any time prior to the EOS visit will continue to be followed every 3 months for survival status until the EOS visit.~An adaptive 2-stage design will be used for each cohort in this study. For each cohort, approximately 8 participants will be enrolled in Stage 1. The decision to move to Stage 2 enrollment will be based on an interim analysis of the first 8 evaluable participants in the cohort using investigator's assessment (per defined radiologic, clinical, and/or laboratory response criteria). The number of participants enrolled in Stage 2 for each cohort will depend on the number of observed responders in Stage 1.
The purpose of this study is to assess the efficacy and safety of tabelecleucel in participants with Epstein-Barr virus (EBV) associated diseases.