TDM-guided valganciclovir dosing for CMV prophylaxis in lung transplant recipients

Results from a single-center, prospective cohort study with a historical control group, evaluating therapeutic drug monitoring (TDM)-guided valganciclovir dosing for cytomegalovirus (CMV) prophylaxis in adult lung transplant recipients, were published in the Journal of Infection and Chemotherapy by Katada et al. Historical controls received conventional dosing (n = 42) while the TDM-guided dosing group targeted ganciclovir trough concentrations of 300–800 ng/mL (n = 45). The primary outcome was valganciclovir discontinuation due to adverse events (AEs), with secondary outcomes including valganciclovir-related AEs and CMV infection during prophylaxis. 

Key data: Valganciclovir discontinuation due to AEs occurred in 35.7% of control vs 11.1% of TDM-guided patients (hazard ratio [HR], 0.303; 95% confidence interval [CI], 0.126–0.730), with leukopenia and neutropenia the most common causes of discontinuation. Median times to discontinuation due to AEs were 31.0 vs 39.0 days for the control vs TDM-guided group, respectively. Grade ≥3 neutropenia risk was lower with TDM-guided dosing (risk ratio [RR], 0.117; 95% CI, 0.015–0.894). Target ganciclovir trough concentrations of 300–800 ng/mL were achieved in 40.5% vs 62.2% of patients in the control and TDM-guided groups, respectively. CMV infection during prophylaxis occurred in 2.4% of control vs 0% of TDM-guided patients, with no CMV disease in either group. 

Key learning: TDM-guided valganciclovir dosing may serve as a practical strategy to mitigate hematological toxicity and improve treatment continuation rates in lung transplant recipients, with prospective validation needed before broad implementation.