EHA2026 Congress: PTLD highlights

Catch up with key insights from the 31st Annual Meeting of the European Hematology Association (EHA2026 Congress) on early prophylactic rituximab to reduce Epstein–Barr virus (EBV) infection and post-transplant lymphoproliferative disorder (PTLD), and key data on tabelecleucel and chimeric antigen receptor (CAR) T-cell therapy.

Key PTLD data from EHA2026

Rituximab prophylaxis reduces EBV and PTLD risk​

By Laura Boyd

Prophylactic rituximab significantly reduced Epstein–Barr virus (EBV) infection and post-transplant lymphoproliferative disorder (PTLD) compared with a preemptive strategy in patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT), according to results from a multicenter retrospective cohort study presented at the EHA2026 Congress.

At 180 days, the cumulative incidence of EBV reactivation was markedly lower in patients who received prophylactic rituximab compared with those managed with a preemptive approach (4.58% vs 37.87%; P<0.001). PTLD incidence was also reduced (0.93% vs 4.52%; P=0.015).

Ao Zhang (Shanghai Rui Jin Hospital, China) presented the data, reporting that prophylactic rituximab remained an independent protective factor for EBV infection in multivariable analysis (adjusted HR, 0.14; P<0.001), and noted that early B-cell depletion may reduce EBV infection by depleting the viral reservoir before EBV DNA becomes detectable.

The study comprised 714 patients undergoing their first anti-thymocyte globulin (ATG)-based allo-HCT, across three transplant centers between April 2021 and October 2025, with no prior history of EBV-associated hemophagocytic lymphohistiocytosis or lymphoma. Patients were stratified based on receipt of at least one dose of rituximab (375 mg/m²) between day −15 and day +30 (R+ group, n=280) or no prophylaxis (R− group, n=434).

Further analyses showed that the protective effect was most pronounced during the early post-transplant period. EBV infection between days 30 and 100 was substantially reduced with prophylaxis, while rates were comparable beyond day 100, highlighting a defined high-risk window for EBV reactivation following ATG exposure.

Prophylactic rituximab did not adversely affect key transplant outcomes. Two-year overall survival, relapse-free survival, and hematologic recovery were similar between groups. T-cell and natural killer cell recovery remained intact, although B-cell recovery was delayed, consistent with the expected pharmacologic effect of rituximab.

The incidence of grade 2–4 acute graft-versus-host disease was lower in the prophylactic group, although not significantly, and non-relapse mortality was similar between groups (9.1% vs 10.5%).

Zhang concluded that early prophylactic rituximab represents a “risk-adapted strategy in selected high-risk allo-HCT populations” that shifts EBV management from reactive treatment to prevention, although prospective multicenter studies are needed to confirm these findings and define optimal use.

​Trial and real-world data on cellular therapies in PTLD​

By Agata Buczak

Prospective and real-world analyses of cellular therapies presented at the EHA2026 Congress provided insights into treatment outcomes in PTLD.

Sylvain Choquet (University Hospital Pitié Salpétrière, Paris, France) presented updated results from the phase 3 ALLELE trial evaluating tabelecleucel in patients with relapsed or refractory EBV-positive (EBV+) PTLD. The overall response rate (ORR) in the full analysis set was 49.4%. ORRs reached 53.1% in the hematopoietic stem cell transplant (HSCT) group and 47.4% in the solid organ transplant (SOT) population. Median overall survival (OS) was not estimable in responders, with a 1-year OS rate of 83.6%. Median progression-free survival (PFS) was 25.6 months in responders, with a 1-year PFS rate of 75.0%.

Tabelecleucel was associated with a manageable safety profile. Treatment-related adverse events, including cytokine release syndrome, were reported in a minority of patients, alongside low rates of severe toxicity.

Choquet concluded that these data, consistent with previous reports, demonstrate “substantial OS and PFS benefit in patients with relapsed or refractory EBV+ PTLD, who otherwise have a poor probability of survival.”

Chiara Consoli (University of Turin, Italy) shared real-world data on tabelecleucel in a multicenter observational study of patients with relapsed or refractory EBV+ PTLD. The ORR was 35%, consistent with ALLELE trial findings, with complete remission in 30% of patients. Outcomes appeared to vary by transplant type, with poorer outcomes observed in patients who underwent HSCT (ORR, 11.1%) compared with those who underwent SOT (ORR, 54.5%). Treatment was generally well tolerated, with no significant toxicity reported. Consoli noted that early referral and timely product allocation remain critical, as delays and product unavailability limit treatment delivery in some patients.

Fabio Andreozzi (Institut Jules Bordet, Brussels, Belgium) presented real-world evidence on anti-CD19 chimeric antigen receptor (CAR) T-cell therapy on behalf of the European Society for Blood and Marrow Transplantation (EBMT) Lymphoma Working Party. This retrospective analysis of 23 patients with PTLD reported a 1-year OS of 74.7% and a PFS rate of 62.4%. The relapse incidence was 32.2%, while non-relapse mortality remained low at 5.4%. Andreozzi concluded that “CAR T-cell therapy represents a feasible and potentially effective option for patients with PTLD failing standard therapies.” Additional data are being collected to expand the cohort and confirm these preliminary findings.

Collectively, these studies reflect the ongoing evaluation of cellular therapies in PTLD, demonstrating clinical activity across prospective and real-world settings, while highlighting variability in outcomes and the need for further evidence, as noted by the presenters.