Hybrid Ganciclovir/Valacyclovir Prophylaxis Reduces CMV Reactivation in High-Risk Allogeneic Stem Cell Transplant...

Area of Science:

• Hematology
• Infectious Diseases
• Transplantation Immunology

Background:

• Cytomegalovirus (CMV) reactivation is a major complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT), especially in CMV-seropositive patients receiving transplants from alternative donors.
• Letermovir, a standard prophylaxis, is often unavailable or too expensive in resource-limited settings.

Purpose of the Study:

• To evaluate the efficacy of a hybrid CMV prophylaxis regimen (pretransplant ganciclovir followed by high-dose valacyclovir) compared to a standard preemptive strategy.
• To assess CMV reactivation incidence and survival outcomes in adult acute leukemia patients undergoing allo-HSCT from alternative donors.

Main Methods:

• Prospective single-center cohort study of 80 adult acute leukemia patients receiving allo-HSCT from alternative donors (November 2018 - May 2022).
• Patients were divided into two groups: hybrid prophylaxis (n=34) and preemptive regimen (n=46).
• Primary outcome: CMV reactivation incidence at 90 days post-transplant. Secondary outcomes: overall survival (OS), disease-free survival (DFS), GVHD-free relapse-free survival (GRFS), and non-relapse mortality (NRM).

Main Results:

• The hybrid prophylaxis group showed a significantly lower incidence of CMV reactivation at 90 days (34%) compared to the preemptive group (82%) (P=0.000).
• No statistically significant differences were observed in OS, DFS, GRFS, or NRM between the two groups.

Conclusions:

• The hybrid CMV prophylaxis regimen effectively reduces CMV reactivation in high-risk allo-HSCT recipients.
• While not improving survival outcomes, this regimen provides a practical and accessible alternative for CMV prophylaxis in resource-limited settings where Letermovir is not feasible.