Comparison of valganciclovir versus foscarnet for the treatment of cytomegalovirus viremia in adult acute leukemia patients after allogeneic hematopoietic cell transplantation

Cytomegalovirus (CMV) reactivation increases treatment-related mortality (TRM) after allogeneic hematopoietic cell transplantation (allo-HCT). We analyzed 141 adult acute leukemia (AL) patients suffered allo-HCT between 2017 and 2021, who developed CMV viremia post-HCT and treated with valganciclovir or foscarnet, to evaluate effectiveness and safety of both drugs. Viremia clearance rates (14 and 21 d post treatment) and toxicities were similar in two groups. However, valganciclovir was associated with a lower cumulative incidence of CMV recurrence within 180 days (16.7% vs. 35.7%, p=0.029) post CMV clearance. Finally, 2-year TRM was lower in valganciclovir group (9.7% +/- 0.2% vs. 26.2% +/- 0.3%, p = 0.026), result a superior 2-year overall survival (OS; 88.1% +/- 5.2% vs. 64.4% +/- 5.5%, p = 0.005) and leukemia-free survival (LFS; 82.0% +/- 5.9% vs. 58.9% +/- 5.6%, p = 0.009). Valganciclovir might decrease CMV viremia recurrence and led to better long-term outcome than foscarnet in adult AL patients developed CMV viremia post-HCT. Considering the inherent biases of retrospective study, well-designed trials are warranted to validate our conclusion.