Antithymocyte Globulin Versus Interleukin-2 Receptor Antagonist in Kidney Transplant Recipients With Hepatitis C Virus

Background. Hepatitis C virus-positive (HCV+) kidney transplant (KT) recipients are at increased risks of rejection and graft failure. The optimal induction agent for this population remains controversial, particularly regarding concerns that antithymocyte globulin (ATG) might increase HCV-related complications. Methods. Using Scientific Registry of Transplant Recipients and Medicare claims data, we studied 6780 HCV+ and 139 681 HCV- KT recipients in 1999-2016 who received ATG or interleukin-2 receptor antagonist (IL2RA) for induction. We first examined the association of recipient HCV status with receiving ATG (versus IL2RA) using multilevel logistic regression. Then, we studied the association of ATG (versus IL2RA) with KT outcomes (rejection, graft failure, and death) and hepatic complications (liver transplant registration and cirrhosis) among HCV+ recipients using logistic and Cox regression. Results. HCV+ recipients were less likely to receive ATG than HCV- recipients (living donor, adjusted odds ratio [aOR] = (0.64)0.77(0.91); deceased donor, aOR = (0.71)0.81(0.92)). In contrast, HCV+ recipients who received ATG were at lower risk of acute rejection compared to those who received IL2RA (1-y crude incidence = 11.6% versus 12.6%; aOR = (0.68)0.82(0.99)). There was no significant difference in the risks of graft failure (adjusted hazard ratio [aHR] = (0.86)1.00(1.17)), death (aHR = (0.85)0.95(1.07)), liver transplant registration (aHR = (0.58)0.97(1.61)), and cirrhosis (aHR = (0.73)0.92(1.16)). Conclusions. Our findings suggest that ATG, as compared to IL2RA, may lower the risk of acute rejection without increasing hepatic complications in HCV+ KT recipients. Given the higher rates of acute rejection in this population, ATG appears to be safe and reasonable for HCV+ recipients.