Background. Valganciclovir has been widely used for cytomegalovirus (CMV) prophylaxis in solid-organ transplant recipients. However, the optimal dosing protocol and target exposure in children is still unclear. Specific data as to the efficacy and safety of low dose/low exposure regimens and their comparison to high dose/high exposure regimens are lacking and are urgently needed.
Methods. During 2010-2015, the clinical efficacy and safety of a weight-based regimen of valganciclovir 17mg/mg/day for 3-6 months given as CMV prophylaxis were evaluated among pediatric kidney and liver transplant recipients, 12 months post-transplantation. Incidence of CMV infection assessed by periodic measurements of viral load and adverse events were compared between this regimen and the manufacturer’s recommended body surface area and glomerular filtration rate-based protocol used in an historical control group.
Results. Eighty-three children, median age of 9.77 (range 0.6-18.9) who had undergone 86 transplantations and been treated with 17mg/mg valganciclovir were included. Twelve (14%) developed CMV infection, one during prophylaxis and 11 during follow-up. In comparison to the manufacturer’s-dosing regimen, no significant difference was found in the incidence of CMV infection during the first year post-transplantation between the dosing regimens (15.15% vs. 19.64%, p=0.551). However, a significantly lower rate of adverse effects was demonstrated using the 17mg/kg regimen (10.6% vs. 48.2%, p<0.001).
Conclusions. Our results support the use of 17mg/kg valganciclovir for CMV prophylaxis in liver and kidney transplanted children as it presents with similar efficacy and a better safety profile compared with the manufacturer’s recommended regimen. These data should encourage additional large prospective studies and the consideration of revising the current guidelines for CMV prophylaxis in pediatric kidney and liver transplant recipients.
