Limited-Dose Daclizumab Versus Basiliximab: A Comparison of Cost and Efficacy in Preventing Acute Rejection K. Pham, K. Kraft, J. Thielke, J. Oberholzer, H. Sankary, G. Testa, and E. Benedetti ABSTRACT The purpose of this study was to compare the efficacy and cost of the limited-dose Daclizumab regimen to that of the standard-dose Basiliximab regimen. Two antibody induction regimens were compared in patients aged 18 years and older who received renal transplants from January 2002 to September 2003 and completed interleukin (IL)-2R antibody induction with standard-dose Basiliximab (20 mg  2 doses) or limited-dose Daclizumab (1 mg/kg  2 doses). The primary outcome measure was the incidence of acute rejection. Secondary outcomes included cost, changes in serum creatinine level, and delayed graft function. Of the 46 patients randomized, 42 patients completed the 6-month follow-up. Mean serum creatinine level at time of discharge was originally higher in the limited-dose Daclizumab group than the standard-dose Basiliximab group (1.89 vs 1.57, respectively). By 1, 3, and 6 months, mean serum creatinine values were similar between both groups, with a trend toward lower mean serum creatinine values in the limited-dose Daclizumab group. The incidence of acute rejection was also similar between the groups (6% vs 7%). The average cost difference between the 2 regimens was approximately $715. This study suggests that a limited-dose Daclizumab regimen may be an efficacious and less costly alternative to the standard-dose Basiliximab regimen for antibody induction therapy following renal transplantation. A CUTE allograft rejection occurs primarily in the first 3 months after solid organ transplantation and is one of the most important causes of chronic rejection and late graft loss. Newer immunosuppressive agents used for induc- tion and maintenance therapy have reduced the incidence of acute rejection but are accompanied by numerous side effects. The nephrotoxic effects of calcineurin inhibitors can be reduced with induction therapy with antibody prepara- tions such as antilymphocyte or antithymocyte globulins (ALG/ATG). However, these polyclonal preparations are associated with toxicity resulting from cytokine release and other side effects such as leukopenia and thrombocytope- nia. Early monoclonal antibodies (such as OKT3) were developed to deplete specific target cells or modulate specific antigens, but their interaction with CD3 cells also led to a cytokine release syndrome with severe side effects, such as fever, chills, diarrhea, and cardiovascular problems. An increased rate of posttransplantation lymphoprolifera- tive disorders also resulted from these nonspecific immu- nosuppressants. 1 One potential target for more specific immunosuppres- sive therapy with humanized monoclonal antibodies is the interleukin (IL)-2 (CD 25) receptor, which induces rapid proliferation of T lymphocytes when IL-2 binds to it. This inhibits alloreactive T cells from infiltrating the allograft and helps prevent acute rejection. 1,2 Addition of IL-2 receptor antibodies to cyclosporine-based immunosuppres- sive regimens decreases the risk of acute rejection by 49% at 6 months posttransplantation without increasing the risk of infection. 3 Basiliximab (Simulect) and Daclizumab (Ze- napax) are FDA-approved IL-2R monoclonal antibodies, biologically engineered to contain more human gene and fewer murine-derived regions with potentially fewer side effects. Both agents have been shown to be equally safe with minimal added toxicity to cyclosporine-based regimens. 3,4 Basiliximab was given as 20-mg doses on the day of surgery and postoperative day (POD) 4. In phase 1 trials of From the Departments of Pharmacy Practice (K.P., K.K., J.T.), and Department of Surgery (J.O., H.S., G.T., E.B.), Division of Transplantation, University of Illinois at Chicago, Chicago, Ill, USA. Address reprint requests to Enrico Benedetti, MD, 840 S. Wood Street, Suite 402, Chicago, IL 60612. E-mail: enrico@uic.edu © 2005 by Elsevier Inc. All rights reserved. 0041-1345/05/$–see front matter 360 Park Avenue South, New York, NY 10010-1710 doi:10.1016/j.transproceed.2004.12.079 Transplantation Proceedings, 37, 899 –902 (2005) 899