We report an experience with 71 simultaneous kidney-pancreas transplant (SKPT) recipients receiving daclizumab induction in combination with tacrolimus (TAC), mycophenolate mofetil (MMF), and steroids. The mean follow-up time was 5.9+/-2.5 (SD) months (range 0.5-11 months). The study population included 47 males (65%) and 24 females (35%) with a mean age of 40+/-8 years. The mean pretransplant duration of diabetes and dialysis were 25+/-8 and 1.5+/-0.9 years (34 hemodialysis, 16 peritoneal dialysis), respectively. Mean HLA match was 1.2+/-1.5, with one patient receiving a second transplant. The mean cold ischemic times for the kidney and the pancreas were 15+/-5 and 16+/-4 hr, respectively. Six-month patient, kidney, and pancreas graft survival and rejection rates were 97, 96, 93, and 35%, respectively. There were two deaths, one due to fungal infection and the other due to a cardiac event. There were three kidney graft losses, two immunological, and one death with function. Of the five pancreas graft losses, two were due to infection, one immunological, one thrombosis, and one death with function. The patient population was then stratified according to the number of daclizumab doses: 4-5 doses (n=45) or 1-3 doses (n=26). There were no differences in patient and kidney graft survival rates, 98 vs. 96%, and 92 vs. 92%, respectively. However, there was a trend toward improved pancreas graft survival in the group receiving 4-5 doses (96%) compared with 1-3 doses (85%), P=0.07. Although more patients receiving 1-3 doses had rejection (54%) than patients receiving 4-5 doses (24%), there was no dose response relationship between the total number of doses or the adjusted total mg/kg dose and time to rejection. All patients with functioning grafts have good renal and pancreas allograft function at 6 and 12 months. The overall incidence of major infection was 27% and there were no differences in the incidence of infection between the two groups. No major adverse events were attributed to daclizumab use. In conclusion, excellent short-term outcomes were noted in this retrospective, multicenter survey of initial experience with daclizumab induction in combination with TAC, MMF, and steroids in SKPT recipients. Optimal dosing strategies for SKPT recipients remain to be determined.