Reducing Post-Letermovir CMV Infection: Efficacy of an Immune-Reconstitution-Based Scoring System to Guide Prophylaxis Duration

With the increasing use of letermovir and considering that haploidentical hematopoietic stem cell transplantation (haplo-HSCT) predominates in China alongside a high CMV seroprevalence in the population, multiple domestic centers have reported cases of CMV infection after letermovir discontinuation. Currently, there is no clear definition for the high-risk population who may benefit from extended letermovir prophylaxis. This study aims to utilize CMV-specific immune reconstitution to identify high-risk individuals for CMV infection after letermovir cessation post-transplant, thereby guiding the timing of letermovir discontinuation and balancing the risks and safety associated with prolonged prophylaxis.