Abstract
BACKGROUND: Cytomegalovirus (CMV) infection is a leading complication following hematopoietic stem cell transplant (HSCT) and solid organ transplant (SOT). Virus-specific T cells (VSTs) have been used for the prophylaxis and treatment of CMV infections. We conducted a scoping review to catalogue and characterize the existing literature. METHODS: Systematic searches were performed in collaboration with an expert librarian. Inclusion criterion was the use of CMV-VST for prophylaxis or treatment in HSCT and SOT patients. Major exclusion criteria were case reports and series with <5 cases. Databases were queried from inception to 31 May 2024. Of the 2587 identified abstracts, full text review was performed on 92 articles, and 67 studies underwent final data extraction. RESULTS: Most studies were in the HSCT population. The CMV infection rate was 28% (interquartile range [IQR], 14%-44%) when CMV-VSTs were used as prophylaxis. Response rates for non-refractory and/or resistant (R/R) infections and R/R infections in HSCT patients were 98% (IQR, 70%-100%) and 70% (IQR, 56%-88%), respectively. Four studies included SOT patients with R/R infections, demonstrating a response rate of 15%-64%. Variables including donor/recipient serostatus and antiviral use were heterogeneously reported, and various definitions of CMV infection and response were used. CMV-VSTs were well-tolerated with minimal adverse events reported. CONCLUSIONS: CMV-VSTs are more commonly used in HSCT patients with limited data in SOT patients, and differential reporting of key variables precludes extrapolation. A standardized registry should be considered for future studies with additional focus on the optimal dosing, timing, and interaction with concurrent antivirals.