Immune Monitoring and CNI Withdrawal in Low Risk Recipients of Kidney Transplantation

INCLUSION CRITERIA - Initial Enrollment/Screening: Patients who meet all of the following criteria are eligible for enrollment as study subjects: * Subject must be able to understand and provide written informed consent; * Primary living-donor (related or unrelated) kidney transplant recipients; * Peak flow-based PRAs for class I and class II \<30%(performed by local center); * Current (within 8 weeks prior to transplantation) flow-based PRAs for class I and class II \<30% (performed by local center); * No donor specific antibody by flow solid phase method on the peak PRA serum (if serum available), or on the current PRA serum (within 8 weeks prior to transplantation) performed by central core laboratory. If the sera for the peak PRA is not available, then only the current PRA serum will be tested; * Negative T-cell and B-cell crossmatch by flow cytometry (performed by local center); * Female subjects of childbearing potential must have a negative pregnancy test (urine or serum) upon study entry; * Female and male subjects with reproductive potential must agree to use FDA approved methods of birth control while participating in the study. Inclusion Criteria for Randomization: Participants who meet all of the following criteria are eligible for randomization: * No history of acute rejection episodes; * The pre-randomization protocol biopsy should confirm no rejection, including borderline rejection (based on the central pathology read); * No donor specific antibody as detected by flow solid phase method (performed by the central core laboratory). EXCLUSION CRITERIA - Initial Enrollment/Screening: Participants who meet any of these criteria are not eligible for enrollment as study subjects: * Recipient of multiple organ transplants; * Prior history of organ transplantation; * Deceased-donor source; * Any condition that would preclude protocol biopsies; * HLA identical recipients; * Currently breast-feeding or plans to become pregnant during the timeframe of the study follow up period; * Any condition that, in the opinion of the investigator, would interfere with the subject's ability to comply with study requirements; * Inability or unwillingness to comply with study protocol; * Use of investigational drugs within 4 weeks of study entry and for the duration of the study; * Recent recipient of any licensed or investigational live attenuated vaccine(s) within two months of prior to study entry. Exclusion Criteria for Randomization: Participants who meet any of these criteria are not eligible for randomization: * Subjects who receive less than 4.5mg/kg of Rabbit ATG (Thymoglobulin®) induction therapy; * Subjects who test positive for BKV by PCR in the blood at 6 months post-transplant; * Any condition that would preclude protocol biopsies; * Currently breast-feeding or plans to become pregnant during the timeframe of the study follow up period; * Any condition that, in the opinion of the investigator, would interfere with the subject's ability to comply with study requirements; * Inability or unwillingness of a subject to give written informed consent or comply with study protocol; * Use of investigational drugs within 4 weeks of study entry and for the duration of the study; * Subjects who receive less than 1500 mg daily of Mycophenolate Mofetil (CellCept®) or equivalent.