CareDx, Inc. — The Transplant Company announced the publication of the Kidney Allograft Outcomes AlloSure Registry (KOAR) study in the American Journal of Transplantation. The landmark prospective study demonstrates the clinical utility of AlloSure donor-derived cell-free DNA (dd-cfDNA) in improving rejection detection and guiding biopsy decisions in kidney transplant recipients.
The KOAR study enrolled 1,743 patients across 56 U.S. transplant centers to evaluate the clinical utility of a dd-cfDNA surveillance protocol based on the DART study, which prescribed seven tests in year one and four annually in years two and three. A total of 18,584 AlloSure tests were obtained from the overall cohort.
Key findings include:
Elevated AlloSure was associated with a 6-fold increase in rejection yield in surveillance biopsies (39% vs. 7%, p<0.001) and a 4-fold increase in for-cause biopsies (47% vs. 12%, p<0.001).
AlloSure elevations were detectable up to four months before ABMR and one month before TCMR.
In post-biopsy monitoring, AlloSure levels declined significantly following treatment, while serum creatinine remained unchanged.
The study also demonstrated that dd-cfDNA levels correlate with rejection severity, with higher levels associated with ABMR and mixed rejection, and lower levels linked to borderline or TCMR 1A.
