Background. Despite the prevalent use of rabbit antithymocyte globulin (rATG) as an induction agent in kidney transplantation, the appropriate dose for preventing acute rejection in high-risk patients is not known. Few studies have examined total exposure of rATG less than 6 mg/kg, with fewer studies examining lower dose rATG in patients with increased risk factors for acute rejection.
Methods. We retrospectively analyzed outcomes of 83 kidney transplant recipients at increased risk for acute rejection (repeat transplant, African American race, and panel reactive antibody ≥20%) from July 2004 to July 2007 who were treated with rATG 1.5 mg/kg per day for 3 (n=39) or 4 (n=44) doses for induction to determine the impact of reduced-exposure rATG in the prevention of acute rejection. rATG was initiated intraoperatively and continued on consecutive days. All patients received triple maintenance immunosuppression including prednisone and calcineurin inhibitor. Patients requiring dialysis within 48 hr after transplant were excluded from analysis.
Results. One-year acute rejection rates were 10% and 11% in the 3- and 4-dose cohorts, respectively, with 100% patient and graft survival at 1 year in both groups. Patients in the 3-dose cohort were discharged from the hospital sooner than the 4-dose cohort (median length of hospital stay, 3 vs. 4 days; P=0.004).
Conclusions. Our results suggest that a 3- or 4-dose course of rATG (1.5 mg/kg/dose) provides excellent protection against acute rejection even in patients at increased risk, with the potential for cost savings from a reduction in hospital stay and medication administration.
1 Department of Pharmacy, University of Colorado Denver, CO.
2 Division of Renal Diseases and Hypertension, University of Colorado Denver, CO.
3 Department of Pediatrics, University of Colorado Denver, CO.
The authors declare no conflicts of interest.
Patrick Klem participated in research design, performance of the research, and writing; James E. Cooper participated in the performance of the research; Andrew S. Weiss participated in the performance of the research; Jane Gralla participated in the data analysis and writing of the manuscript; Phillip Owen participated in the performance of research; Laurence Chan participated in the research design and writing of the manuscript; and Alexander C. Wiseman participated in research design, performance of the research, data analysis and writing of the manuscript.
4 Address correspondence to: Alexander C. Wiseman, M.D., Transplant Center, University of Colorado Health Sciences Center, Mail Stop F749, AOP 7089, 1635 North Ursula Street, Aurora, CO 80045.
Received 23 March 2009. Revision requested 15 April 2009.
Accepted 16 June 2009.