1564. Lower Rates of Epstein–Barr Virus (EBV) Viremia in Pediatric Solid Organ Transplant (SOT) Recipients Who Received Valganciclovir Prophylaxis

BACKGROUND: Antiviral prophylaxis to prevent PTLD remains controversial, but some data suggest that valganciclovir or ganciclovir ([val]ganciclovir) use in EBV high-risk pediatric renal transplants reduces EBV viremia. We evaluated the impact of [val]ganciclovir on EBV viremia and post-transplant lymphoproliferative disease (PTLD) in pediatric nonrenal SOT recipients. METHODS: Retrospective study of 100 patients who underwent a first heart, liver, lung, intestine, or multivisceral SOT between November 2013 and November 2016 at Boston Children’s Hospital who survived without re-transplantation for at least 30 days. Data collected included EBV donor/recipient serostatus, donor’s age >2 years-old (to avoid misclassification of EBV risk due to maternal antibody), antiviral use ([val]ganciclovir or acyclovir), time to EBV viremia (>1,000 copies/mL by whole blood PCR), and time to development of PTLD. EBV high-risk patients were those with donor EBV positive [D+]/recipient EBV negative [R–] serologies; intermediate-risk were EBV R+; low risk were EBV D–/R–. Time-to-event analysis using the Kaplan–Meier method was performed and significance (P = 0.05) was evaluated using the log-rank test. RESULTS: High (n = 45) or intermediate (n = 27) EBV risk was associated with increased EBV viremia (P = 0.007, table). EBV viremia was significantly decreased in the subgroup of high-risk patients with donors >2 years old who received [val]ganciclovir vs. those who received no antiviral (n = 23, n = 4, P = 0.03, Figure 1). Most PTLD cases (8/9) occurred in the high-risk group (P = 0.03, Figure 2). Overall, patients who received [val]ganciclovir had less PTLD than those who did not (P = 0.03), but this was not significant in the high-risk subgroup (P = 0.14, Figure 3). CONCLUSION: Lower rates of EBV viremia occurred in high EBV risk transplant recipients who received [val]ganciclovir, possibly by preventing primary EBV infection. Recipients with high EBV risk have the highest rate of PTLD. [Image: see text] [Image: see text] [Image: see text] DISCLOSURES: F. M. Marty, Merck: Consultant and Investigator, Consulting fee, Research support and Speaker honorarium; Astellas: Consultant and Investigator, Consulting fee and Research support; Chimerix: Consultant and Investigator, Consulting fee and Research support; Fate Therapeutics: Consultant, Consulting fee; GlaxoSmithKline: Consultant, Consulting fee; LFB: Consultant, Consulting fee; Roche Molecular Diagnostics: Consultant, Consulting fee; Shire: Consultant and Investigator, Consulting fee and Research support.