Letermovir Prophylaxis in Children With EBV-Positive T/NK-Cell Lymphoproliferative Disease and Refractory/Relapsed EBV-Associated Hemophagocytic Lymphohistiocytosis
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Letermovir.
- Who it may be relevant to
- Registry conditions: EBV-associated T/NK-cell Lymphoproliferative Diseases, Refractory/Relapsed EBV-related Hemophagocytic Lymphohistiocytosis, Letermovir. Basic parameters: up to 18 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- China
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Impact of Letermovir Prophylaxis on Viral Infections After Allogeneic Hematopoietic Stem Cell Transplantation in Children With EBV-Positive T/NK-Cell Lymphoproliferative Disease and Refractory/Relapsed EBV-Associated Hemophagocytic Lymphohistiocytosis
Overview
This study investigates the impact of letermovir prophylaxis on viral infections (including CMV, EBV, BKV, HHV-6/7, RSV, ADV, HSV, etc.) following allogeneic hematopoietic stem cell transplantation in pediatric patients with EBV-associated T/NK-cell lymphoproliferative diseases and refractory/relapsed EBV-related hemophagocytic lymphohistiocytosis. Additionally, we examine its effects on other transplantation complications, including engraftment failure, graft-versus-host disease (GvHD), disease relapse, thrombotic microangiopathy (TMA), overall survival (OS), post-transplant lymphoproliferative disorder (PTLD) incidence, and immune reconstitution.
Interventions
- Drug Letermovir
Arm 1 (Letermovir Prophylaxis): Pediatric patients receive oral letermovir once daily from day 0 to day 100 post-transplant. Prophylaxis may be extended to day 200 if high-risk factors persist (steroid use, poor immune reconstitution). Dosing: 480mg (≥30kg), 240mg (15-30kg), 120mg (7.5-15kg), 80mg (6-7.5kg); halved if co-administered with cyclosporine. Arm 2 (Control): Historical control cohort (2018-2023) receiving no routine CMV prophylaxis; preemptive therapy with ganciclovir/foscarnet initi
Primary outcome measures
- Incidence of Clinically Significant CMV Infection (cs-CMVi) and EBV Infection (cs-EBVi) [Time frame: Up to 180 days and 360 days post-transplant]
Secondary outcome measures (1)
- Incidence of Other Viral Infections and Transplant-Related Complications [Time frame: Up to 100, 180, 270, and 360 days post-transplant]
Eligibility criteria
Inclusion criteria
- Diagnosed with EBV-positive T/NK lymphoproliferative disease (EBV-T/NK LPD) according to ICC 2022 criteria, or diagnosed with refractory/relapsed EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) according to the 2004-HLH diagnostic criteria;
- Undergoing first allogeneic hematopoietic stem cell transplantation (allo-HSCT) at the study center;
- Age < 18 years;
- CMV seropositive (IgG+) prior to transplantation;
- Presence of at least one high-risk factor for CMV infection: haploidentical transplantation, HLA-mismatched transplantation, receipt of ATG (including ATLG/ALG) in conditioning, sustained corticosteroid use post-conditioning, donor/recipient CMV serostatus mismatch, or positive NGS result pre-transplant.
Exclusion criteria
- History of CMV end-organ disease within 6 months prior to enrollment;
- Severe hepatic dysfunction (defined as Child-Pugh Class C);
- End-stage renal impairment with creatinine clearance < 10 mL/min (calculated by Cockcroft-Gault equation);
- Prior allogeneic hematopoietic stem cell transplantation;
- Expected survival ≤ 3 months;
- Received radiation therapy during conditioning;
- Initiation of letermovir prophylaxis after day 28 post-transplant;
- Letermovir dosage or administration not in accordance with the prescribing information;
- Lack of signed informed consent.
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Non-randomized
- Model
- Parallel assignment
- Masking
- Open label
- Primary purpose
- Prevention
Study locations
China · 1 center
- Beijing Children's Hospital, Capital Medical University — Beijing
Identifiers
NCT: NCT07488728 · [2025]-Y-242-D