GEP (AlloMap) score instability has been shown to predict of events of graft dysfunction or death in an analysis of the IMAGE data set by Deng et al. Our goal is to test this hypothesis in the independent CARGO 2 patient data set.In a case-cohort design, patients with >2 serial GEP tests were studied in multivariate Cox regression models to predict future clinical events. Intra-patient GEP score instability was defined as the standard deviation of an individual’s cumulative test scores. GEP score (range 0-39), GEP score ≥34, and GEP score stability were studied.GEP scores tend to rise and become more stable in the whole population during the first year post-transplantation than after 1 year. After 12 months, GEP score instability (p=0.001) and GEP ≥34 (p=0.06) predict future events. [figure 1]