[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"health-studies-list:{\"conditionNormalized\":\"refractoryrelapsed-ebv-related-hemophagocytic-lymphohistiocytosis\",\"overallStatus\":[\"RECRUITING\",\"AVAILABLE\",\"NOT_YET_RECRUITING\"],\"orderBy\":\"LastUpdateSubmitDate:desc\",\"size\":25,\"offset\":0}":3,"health-study-condition:refractoryrelapsed-ebv-related-hemophagocytic-lymphohistiocytosis":27},{"pageToken":4,"total":5,"offset":6,"count":5,"results":7},null,1,0,[8],{"id":9,"slug":10,"hasResults":11,"nctId":12,"briefTitle":13,"officialTitle":14,"acronym":4,"eligibilityCriteria":15,"healthyVolunteers":11,"sex":16,"minAge":4,"maxAge":17,"enrollmentInfo":18,"targetDuration":4,"studyType":21,"phases":22,"briefSummary":24,"conditions":25,"keywords":29,"overallStatus":33,"whyStopped":4,"lastUpdateSubmitDate":34,"lastUpdatePostDateStruct":35,"startDateStruct":38,"completionDateStruct":40,"leadSponsor":42,"locationsCount":5},"100630519","letermovir-prophylaxis-in-children-with-ebv-positive-tnk-cell-lymphoproliferative-disease-and-refractoryrelapsed-ebv-associated-hemophagocytic-lymphohistiocytosis-100630519",false,"NCT07488728","Letermovir Prophylaxis in Children With EBV-Positive T\u002FNK-Cell Lymphoproliferative Disease and Refractory\u002FRelapsed EBV-Associated Hemophagocytic Lymphohistiocytosis","Impact of Letermovir Prophylaxis on Viral Infections After Allogeneic Hematopoietic Stem Cell Transplantation in Children With EBV-Positive T\u002FNK-Cell Lymphoproliferative Disease and Refractory\u002FRelapsed EBV-Associated Hemophagocytic Lymphohistiocytosis","Inclusion Criteria:\n\n* Diagnosed with EBV-positive T\u002FNK lymphoproliferative disease (EBV-T\u002FNK LPD) according to ICC 2022 criteria, or diagnosed with refractory\u002Frelapsed EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) according to the 2004-HLH diagnostic criteria;\n* Undergoing first allogeneic hematopoietic stem cell transplantation (allo-HSCT) at the study center;\n* Age \\\u003C 18 years;\n* CMV seropositive (IgG+) prior to transplantation;\n* Presence of at least one high-risk factor for CMV infection: haploidentical transplantation, HLA-mismatched transplantation, receipt of ATG (including ATLG\u002FALG) in conditioning, sustained corticosteroid use post-conditioning, donor\u002Frecipient CMV serostatus mismatch, or positive NGS result pre-transplant.\n\nExclusion Criteria:\n\n* History of CMV end-organ disease within 6 months prior to enrollment;\n* Severe hepatic dysfunction (defined as Child-Pugh Class C);\n* End-stage renal impairment with creatinine clearance \\\u003C 10 mL\u002Fmin (calculated by Cockcroft-Gault equation);\n* Prior allogeneic hematopoietic stem cell transplantation;\n* Expected survival ≤ 3 months;\n* Received radiation therapy during conditioning;\n* Initiation of letermovir prophylaxis after day 28 post-transplant;\n* Letermovir dosage or administration not in accordance with the prescribing information;\n* Lack of signed informed consent.","ALL","18 Years",{"count":19,"type":20},80,"ESTIMATED","INTERVENTIONAL",[23],"NA","This study investigates the impact of letermovir prophylaxis on viral infections (including CMV, EBV, BKV, HHV-6\u002F7, RSV, ADV, HSV, etc.) following allogeneic hematopoietic stem cell transplantation in pediatric patients with EBV-associated T\u002FNK-cell lymphoproliferative diseases and refractory\u002Frelapsed 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.",[26,27,28],"EBV-associated T\u002FNK-cell Lymphoproliferative Diseases","Refractory\u002FRelapsed EBV-related Hemophagocytic Lymphohistiocytosis","Letermovir",[30,28,31,32],"EBV","EBV-associated T\u002FNK-cell lymphoproliferative diseases","refractory\u002Frelapsed EBV-related hemophagocytic lymphohistiocytosis","RECRUITING","2026-03-18",{"date":36,"type":37},"2026-03-23","ACTUAL",{"date":39,"type":37},"2025-10-01",{"date":41,"type":20},"2026-12-31",{"name":43,"class":44},"Beijing Children's Hospital","OTHER"]