Hospital Exemption Use Of Virus-Specific T-Lymphocytes In Children: Early Experience Within The

The objective is to document feasibility, immediate antiviral activity, and short-term outcomes in a real-world setting outside formal trial enrollment.

• The report describes initial experiences with hospital-exemption virus-specific T lymphocytes (VST) in pediatric transplant recipients within the ALLOVISTA framework.

One patient had concurrent CMV/EBV/ADV infection.

• This is a retrospective, early-experience report involving six children and adolescents treated in two Polish centers.
• Median age was 4.5 years (range 2.5–18.5 years).
• All patients had undergone allogeneic hematopoietic stem cell transplantation and presented with refractory viral infections or reactivation: three with adenovirus (ADV) and three with EBV-driven disease (including EBV-positive post-transplant lymphoproliferative disorder or HL relapse with EBV reactivation).
• Prior therapies included standard antivirals and/or immunochemotherapy (e.g., cidofovir, rituximab, chemotherapy) without durable control.

• VST were generated from either allo-HSCT or related donors using the automated CliniMACS Prodigy Cytokine Capture System (IFN-γ CCS) following antigenic stimulation with viral peptide pools.
• The product was released as an ATMP-HE under the ALLOVISTA protocol.
• A single intravenous infusion was administered at doses ranging from 1.01×10^5 to 1.85×10^6 cells per patient (median 2.5×10^5).

• Virological response assessments were possible in five of the six cases, with follow-up up to four weeks post-infusion.
• Four of the five evaluable patients (80%) achieved at least a one-log reduction in viral load.
• Complete clearance by week 4 occurred in two patients (40%), one with EBV and the other with ADV infection.
• Two additional patients demonstrated marked but incomplete or transient reductions in viral load; one patient showed minimal virological response.
• Despite virological activity, four patients died during the observation period due to disease progression (progressive EBV disease in one; ADV infection in another), HL relapse in one, and multi-organ failure with invasive fungal infection in a patient with multi-viral infection.

• No new-onset or worsening acute graft-versus-host disease (aGVHD) was documented following VST infusion.

• The authors interpret the data as evidence that VST delivered as an ATMP-HE is feasible and capable of rapid antiviral activity in heavily pretreated pediatric patients.
• Limitations include small sample size, heterogeneity of viral infections, and confounding complications that influenced survival.