Valganciclovir prophylaxis extension from 3 to 6 months in high-risk pancreas-transplant recipients does not impact incidence of cytomegalovirus infection at 12 months

Problem: Incidence and impact of CMV infection in pancreas-transplant recipients (PTRs) in the valganciclovir prophylaxis era has not been completely elucidated. Methods: Adult D+/R- PTRs were divided into a current era (1/1/2011-12/31/17; 6-month PPX) and a historic era (1/1/2003-12/31/09; 3-month PPX). Primary objective: effect of prophylaxis extension on the incidence of CMV infection. Secondary objective: impact of extension on valganciclovir-related toxicity (leukopenia) and transplant outcomes. Results: There were 177 D+/R- PTRs in the study period (historic:98, current:79). Prophylaxis extension resulted in significant reduction of CMV infection from 25.4% to 10.9% at 6 months, (57% reduction, p =.021). However, 1-year rates of CMV infection (historic:31% vs current:36%) and end-organ disease (historic:7.7% vs current:6.9%) were not different (p =.93). Prophylaxis extension significantly increased leukopenia (white blood cell count<3 K/uL) at 6 months (historic:9.5% vs current:28.6%, p =.018). On multivariable analysis prophylaxis extension was not associated with reduced rates of CMV infection (p =.99) or CMV end-organ disease (p =.3). Additionally, there was no significant difference in rejection (p =.2), graft survival (p =.08), death-censored graft survival(p =.07) or patient survival (p =.6). Conclusions: Prophylaxis extension in D+/R- PTRs appears to delay time to first CMV but not reduce overall incidence. These findings suggest a hybrid approach, incorporating antiviral withdrawal and protocolized monitoring, may be needed to improve CMV-related outcomes.