POS-744 CLINICAL CORRELATES AND OUTCOMES OF DUAL BASILIXIMAB AND THYMOGLOBULIN INDUCTION IN KIDNEY TRANSPLANT RECIPIENTS: A NATIONAL STUDY

Abstract

The unplanned use of dual induction therapy with interleukin-2 receptor blocking antibodies (IL2rAb) and thymoglobulin (TMG) may portend adverse clinical outcomes compared to either therapy alone. We used national transplant registry data to study clinical correlates and outcomes of single versus dual induction therapy in adult kidney-only transplant recipients in the United States (2005-2018). The risk of death and graft loss at 1 and 5 years according to induction therapy type was assessed using multivariate Cox regression analysis (LCLaHRUCL, adjusted hazard ratio with 95% upper and lower confidence limits). Of the 157,351 adult kidney-only transplant recipients included in the study, 67% were treated with TMG alone, 29% were treated with IL2rAb alone, and 5% were treated with both IL2rAb and TMG. Compared with IL2rAb alone induction, the strongest correlates of IL2rAb and TMG induction included Black race, calculated panel reactive antibody (cPRA) ≥80%, prednisone-sparing maintenance immunosuppression, more recent transplant eras, longer cold ischemia time, and delayed graft function. Compared with induction with TMG alone, dual induction therapy was associated with an increased 5-year risk of death (aHR 1.071.151.23; P<0.0001), death-censored graft failure (aHR 1.051.131.22; P<0.05), and all-cause graft failure (aHR 1.061.121.18; P<0.0001). Approximately 15% of kidney transplant patients who received IL2rAb induction also received TMG induction and these recipients had an increased risk of death and graft loss compared with those who received TMG alone. Further research is needed to develop risk prediction tools to guide a safe and optimal induction protocol for kidney transplant recipients.