Randomized Clinical Trial, Open, Multicenter Parallel, no Suspension Inferiority Prophylactic Treatment With Valganciclovir in Kidney Transplant CMV-seropositive Cellular Immunity to Develop CD8 + CMV-specific Treatment After Induction Thymoglobulin.

Hypothesis: Valganciclovir prophylaxis can be discontinued before 3 months in CMV-seropositive renal transplant recipients receiving induction thymoglobulin when developing CMV-specific cellular immunity after transplantation. Objective Meet the efficacy and safety of valganciclovir prophylaxis suspend in CMV-seropositive kidney transplant recipients with CD8 + cellular immunity CMV-specific transplant, receiving Thymoglobulin induction and maintain cellular immunity-specific CD8 + CMV after transplantation. Design: noninferiority clinical trial (study A) in CMV-seropositive kidney transplant recipients with CMV-specific cellular immunity pretransplant (Quantiferon reactive CMV) received induction with thymoglobulin Patients meeting inclusion criteria will be randomized to: * Control Arm: valganciclovir prophylaxis until day +90 as recommended by the International Consensus document of the TTS (Transplantation 2013:96:333-360). * Experimental arm: prophylaxis with valganciclovir and determination of CMV-specific cellular immunity day +15, +30, +45 and +60. Prophylaxis was discontinued when the patient developed CMV-specific cellular immunity. Patients who did not develop CMV specific immunity continue prophylaxis until day +90. Analysis: The incidence of CMV disease according to the strategy used was calculated using Kaplan-Meier curves that were compared using the log-rank test.