FAVORABLE LONG TERM RESULTS WITH THYMOGLOBULIN (RATG) INDUCTION IN PANCREAS TRANSPLANTATION

Abstract

P411 Aims: Induction therapy with RATG is effective in preventing acute rejection in pancreas transplantation and has replaced OKT3 for induction therapy at most centers. T-cell depletion is more prolonged with RATG than OKT3 and the long-term effects of this have not been fully studied. We changed our pancreas protocol in 6/99 with the availability of RATG. In this study, we evaluate the 3-year outcomes (rejection rates, graft survival, patient survival, current maintenance immunosuppressive therapy) of pancreas transplant recipients who received RATG induction therapy and compare them to pancreas transplant recipients who received OKT3 induction therapy. Methods: A retrospective, single-center analysis was preformed of 37 pancreas transplant recipients who received RATG induction therapy between 6/99 and 12/99 compared to 52 pancreas transplant who received OKT3 induction between 1/98 and 6/99. All patients received tacrolimus (FK506), mycophenolate mofetil (MMF) and prednisone maintenance therapy. Median follow-up was no different between groups (4.18±1.3 yrs RATG vs. 4.67±1.7 yrs. OKT3). Results: Rejection rates (RR) and graft survival were similar in both groups at 1-year and 3-year post-transplant. Rejections occurring after 1-year post-transplant in the RATG-group were mostly (43%) due to noncompliance. Mean doses of FK506, MMF and prednisone were not significantly different between groups at 1-,2- or 3-year post transplant. FK506 levels were significantly higher at 1-year post transplant in the OKT3 group (13.1±4.6 ng/mL OKT3 vs. 10.5±3.4 ng/mL RATG, p=0.01) but were no different at 2- or 3-yrs. post-transplant. Mean ± Standard Deviation The average cost of a 7-day course of RATG therapy ($3873) in this study was lower than the cost of OKT3 therapy at an average dose of 35 mg/10 days ($4200) not including the cost of CD3 monitoring. The median length of stay (LOS) for the initial hospitalization was 10±1.5 days in the RATG group compared to 12±1.6 days in the OKT3 group (p=0.32). CMV infections occurred in 13.5% of RATG-induced patients compared to 19.2% of OKT3-induced patients (p=0.48). Conclusions: Pancreas transplants receiving RATG induction therapy with FK506, MMF and prednisone maintenance immunosuppression experienced comparable outcomes to those treated with OKT3 induction therapy with no increase in CMV infections. RATG induction therapy was less expensive than OKT3 with a decreased median LOS in the RATG group.FigureFigure