Randomized trial to assess the clinical utility of renal allograft monitoring by urine CXCL10 chemokine.

Abstract

Urine CXCL10 is a promising non-invasive biomarker for detection of renal allograft rejection. The aim of this study was to investigate the clinical utility of renal allograft monitoring by urine CXCL10 in a randomized trial. We stratified 241 patients, 120 into an intervention and 121 into a control arm. In both arms, urine CXCL10 levels were monitored at three specific time points (1, 3, and 6 months posttransplant). In the intervention arm, elevated values triggered performance of an allograft biopsy with therapeutic adaptations according to the result. In the control arm, urine CXCL10 was measured, but the results concealed. The primary outcome was a combined endpoint at one-year posttransplant (death-censored graft loss, or clinical rejection between month 1 and one-year, or acute rejection in one-year surveillance biopsy, or chronic active T cell-mediated rejection in one-year surveillance biopsy, or development of de novo donor-specific HLA-antibodies, or estimated GFR<25ml/min). The incidence of the primary outcome was not different between the intervention and the control arm (51% vs 49%; RR 1.04 [95% CI 0.81-1.34]; p=0.80). When including 175/241 (73%) patients in a per-protocol analysis, the incidence of the primary outcome was also not different (55% vs 49%; RR 1.11 [95% CI 0.84-1.47]; p=0.54). The incidence of the individual endpoints was not different as well. This study could not demonstrate a beneficial effect of urine CXCL10 monitoring on one-year outcomes (ClinicalTrials.gov_NCT03140514).