SRS299 - What is the right dose of valganciclovir for patients at risk of CMV disease after kidney transplant?

Abstract Background Valganciclovir is used for cytomegalovirus (CMV) prophylaxis in renal transplant recipients but is associated with bone marrow suppression. The formulary dose is calculated using creatine-clearance (Cr-Cl), which includes age of the recipient, although transplanted nephron mass is dictated by donor age. A previous study (1) has found that 450 mg od is both cheaper and as effective at preventing CMV as 900 mg od. Methods Retrospective cohort study of renal transplant recipients between August 2024 and August 2025 at our institution. Results A total of 140 patients were included (56% male, 44% female, mean age 53). 38 of these patients received valganciclovir due to either CMV mismatch or induction with Campath. 1 patient was delayed in receiving their dose, 1 incorrectly dosed and 1 unclear indication. Neutrophil counts at 1 month were non-significantly lower (median 4.7) when discharged on 900 mg compared with 450 mg od (median 7.4, P = NS). When comparing the dose of valganciclovir calculated using the recipient’s age (median CrCl 25 ml/min) versus the donor’s age (median CrCl 30 ml/min) ,there was minimal difference (P = NS). After 3 months, 3 of the 38 patients had developed CMV viraemia. Conclusions The initial results demonstrate a non-significant difference in CrCl calculated using either donor or recipient age. Patients discharged on a lower dose of valganciclovir have equivalent results at 3 months. More details will be available for conference.