Opportunistic CMV viremia (primary infection or reactivation) is usually managed by taking prophylactic medication for both adult and pediatric kidney transplant patients. Most hospitals prescribe valganciclovir for this purpose but valacyclovir has also been used. The most unfavorable side effect of valganciclovir is bone marrow suppression which can be troublesome for kidney transplant patients who are already immunosuppressed. We aim to assess the non-inferiority of valacyclovir compared with valganciclovir in this study.