Long-Term Efficacy of Epstein-Barr Virus-Specific T Cells for Epstein-Barr Virus-Associated Post-Transplantation...

Epstein-Barr virus-associated post-transplant lymphoproliferative disorder (EBV-PTLD) remains a life-threatening complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT), especially in rituximab-refractory cases. Adoptive transfer of EBV-specific cytotoxic T lymphocytes (EBV-CTLs) offers a promising strategy to restore antiviral immunity, but long-term efficacy data remain limited, particularly in haploidentical transplant recipients. We conducted a retrospective study of 41 haploidentical HSCT recipients diagnosed with EBV-PTLD who received donor-derived EBV-CTLs. Patients were monitored for virologic response, adverse events, and transplant outcomes over a median follow-up of 60 months. EBV-CTLs were administered at a median of 25 days after EBV reactivation and 19 days after PTLD diagnosis, following a median of 4 (range, 2 to 8) doses of rituximab. By day 42 postinfusion, the overall response rate was 87.8% (95% confidence interval [CI], 72.0% to 95.0%), accompanied by a marked reduction in peak EBV DNA levels. The 1-year overall survival rate was 68.0% (95% CI, 51.3% to 80.0%), and survival remained stable without significant decline up to 5 years. Donor-derived EBV-CTLs are a safe and effective treatment for EBV-PTLD following haploidentical HSCT. Our findings support the long-term efficacy of cellular immunotherapy in managing viral complications post-transplantation.