Letermovir Prophylaxis Duration Guided by CMV-Specific T-cell Monitoring After Allo-HSCT.

The purpose of this study is to evaluate the efficacy and safety of a personalized strategy for discontinuing Letermovir (a drug used to prevent Cytomegalovirus \[CMV\] infection) based on the recovery of the patient's own immune system. Cytomegalovirus (CMV) is a common and serious complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Currently, Letermovir is typically given as a standard prevention for about 100 days post-transplant. However, some patients may recover their CMV-specific immunity earlier, while others may need longer protection. In this study, researchers will use a dynamic monitoring technology (QuantiFERON-CMV) to detect the level of CMV-specific T-cells in patients. Participants will be randomly assigned to either the experimental group or the control group: Experimental Group: Letermovir discontinuation will be guided by T-cell recovery. If the test shows that the patient's CMV-specific T-cells have recovered, Letermovir may be stopped earlier than the standard 100 days. Control Group: Patients will receive the standard Letermovir prophylaxis for approximately 100 days, regardless of T-cell status. The study aims to determine if this immune-guided strategy can effectively prevent CMV infection while potentially reducing the duration of medication and associated costs, without increasing the risk of CMV disease.

NCT Number	NCT07569653
Lead Sponsor	WeiShi
Conditions	Cytomegalovirus Infections, Cytomegalovirus Disease, Hematopoietic Stem Cell Transplantation, Graft vs Host Disease
Enrollment	120 participants
Start Date	2025-10-30
Primary Completion	2027-10 (estimated)
Study Completion	2027-12 (estimated)
Updated on ClinicalTrials.gov	2026-06-01