Utility of immune monitoring in heart transplant recipients on everolimus-based immune suppression

Everolimus provides effective immune suppression (IS) after heart transplant (HTx). Its pharmacologic properties differentiate everolimus from other IS drugs. A non-invasive immune monitoring (IM) assay test appears to predict the immune state in HTx recipients on standard calcineurin-inhibitor-based IS. The utility of IM in HTx recipients on everolimus-based IS was evaluated. Methods: Between June 2005 and June 2011, 34 adult HTx recipients followed up at our center received everolimus and had 381 IM assays that were performed at six months to 16-yr post-transplant. Results of the IM assay were correlated with infection and rejection episodes that occurred during the IM testing. Results: In the everolimus-based IS group, there were 18 infectious episodes and four rejection episodes. The average IM score was significantly lower during infection than at steady state (188 ± 122 vs. 338 ± 137 ng/mL ATP, p < 0.001) and not significantly different during rejection when compared with steady state (430 ± 132 vs. 338 ± 137 ng/mL ATP, p = 0.5). Conclusions: The non-invasive IM assay predicts infectious risk in HTx recipients on everolimus-based IS. Its inconclusive association with rejection was probably due to the small number of rejections. Serial longitudinal IM may allow proper adjustment of everolimus doses.