The ALLELE trial (NCT03394365) is evaluating tabelecleucel, an off-the-shelf Epstein–Barr virus (EBV)-specific cytotoxic T-cell therapy, for treating relapsed/refractory EBV-associated posttransplant lymphoproliferative disease (R/R EBV+ PTLD) following solid organ transplant (SOT) or hematopoietic stem cell transplant (HCT). Updated clinical results provide insight into its effectiveness, survival outcomes, and safety.
The trial included 75 patients (49 SOT, 26 HCT) treated with tabelecleucel. Patients received a dose of 2 × 10⁶ cells/kg on days 1, 8, and 15 of a 35-day cycle. Responses were assessed using the Lugano Classification with LYRIC modification.
Key Findings
- Overall Response Rate (ORR): 51% (38/75)
- SOT patients: 51% (25/49)
- HCT patients: 50% (13/26)
- Response Breakdown:
- Complete Response (CR): 28% (21/75)
- Partial Response (PR): 23% (17/75)
- Time to Response (TTR): Median 1.1 months
- Duration of Response (DOR): Median 23.0 months
- Clinical Benefit Rate (CR/PR/SD ≥6 months): 60% overall (57% SOT, 65% HCT)
- Overall Survival (OS): Median 18.4 months
- 1-year OS for responders: 79%
- 1-year OS for nonresponders: 28%
No fatal treatment-emergent adverse events were attributed to treatment, and no cases of graft-versus-host disease or organ rejection related to tabelecleucel were observed. The safety profile remained consistent with prior data.
Tabelecleucel continues to show clinical benefit in treating R/R EBV+ PTLD after standard therapies have failed. The data suggest a durable response and favorable survival outcomes, reinforcing its potential as an effective treatment option.
