Background: Induction agents have been shown to reduce the rate of acute rejection. They have not been clearly shown to improve graft and patient survival.
Methods: United Network for Organ Sharing registry data were analyzed to show the status of induction therapy in the United States and to determine the effect of induction therapy on long-term graft and patient survival.
Results: Since establishment of the United Network for Organ Sharing renal transplant registry, there have been three distinct eras of induction regimen: (1) the low-induction, old antibody era, 1987 to 1993, when antilymphocyte globulin and muromonab-CD3 were the major agents; (2) a high-induction, transitional era, 1994 to 2002, when basiliximab (1998), daclizumab (1998), and rabbit antithymocyte globulin (rATG; 1999) replaced antilymphocyte globulin and muromonab-CD3, with maintenance agents also used; (3) the high-induction, modern antibody era, 2003 to present, with most patients receiving rATG, basiliximab, daclizumab, or alemtuzumab (2003). Induction recipients had higher graft and patient survival rates than nonrecipients in all categories of organ transplant. The improvement was statistically significant in kidney, liver, and lung transplants, although liver and lung recipients had a lower percentage of patients receiving induction than did kidney patients. Kidney transplant recipients on alemtuzumab with steroids had the lowest risk of graft failure, followed by those on alemtuzumab alone, rATG with steroids, rATG alone, and then basiliximab with steroids. Improvement was not statistically significant with daclizumab (alone or with steroids), basiliximab alone, or steroids alone.
Conclusion: Induction immunosuppression improved graft and patient outcome for most organ transplants. Depleting agents (alemtuzumab and rATG)--especially in combination with steroids--seem to be more efficient in preventing renal graft failure than nondepleting agents (basiliximab and daclizumab).