This study is for people who have had an organ or cell transplant and developed a disease called EBV+ PTLD after treatment failure with rituximab or chemotherapy. EBV+ PTLD stands for Epstein-Barr virus-associated post-transplant lymphoproliferative disease, which is a condition where the body makes too many white blood cells after a transplant. The study tests a treatment called tabelecleucel, which is given through an IV to see if it helps patients. The treatment is in cycles of 5 weeks, during which patients receive tabelecleucel on specific days followed by observation. The study will follow participants for up to 5 years.

To join, participants need to have had a solid organ or blood cell transplant and meet other health requirements. The study excludes those with certain other health conditions or treatments. If you qualify, you might be asked to provide consent and confirm some health conditions with your doctor.

• Study lasts up to 5 years, with regular follow-ups.
• Treatment involves cycles of IV doses over 5 weeks.
• Participants must have specific health conditions to qualify.