The duration of this trial may differ between participants, depending on when deterioration of kidney graft function occurs. Participants will be followed until graft loss or death. There are no exclusive study visits associated with this study. Study data are gathered from routine laboratory follow-up tests completed at the participant's local medical center and from information obtained at the time of kidney biopsy. Participants may need to undergo a kidney biopsy as clinically indicated. At the time of biopsy, participants will also undergo urine and blood collection.