Immunosuppression for cadaveric renal allograft recipients: A risk-factor matched comparison of the Minnesota Randomized Trial with a antilymphoblast globulin, azathioprine, cyclosporine, and prednisone protocol

Our prospective, randomized trial comparing cyclosporine (CSA) and prednisone (P) with azathioprine (AZA)-P-antilymphoblast globulin (ALG) in cadaveric renal transplant patients from 1980 to 1984 demonstrated that CSA-P treatment produced slightly higher graft survival rates, fewer acute rejection episodes, less infectious complications, and shorter hospital stays while the AZA-P-ALG treatment produced lower serum creatinine levels and a shorter duration of delayed graft function. In an attempt to capture the benefits of each protocol, we began evaluating a CSA-P-AZA-ALG regimen in cadaveric renal allograft recipients. In this report, we compared the 1st year results of this new four-drug protocol given to 78 patients with the 1st yr results of the two-drug regimens previously studies (CSA-P, n = 81 and AZA-P-ALG, n = 75). The three groups were matched for age, sex, number of retransplants, and diabetic status, and all patients were followed for at least 1 yr posttransplant. The overall 1-yr actual patient survival rates were 94% for CSA-P-AZA-ALG, 90% for CSA-P, and 88% for AZA-P-ALG. Actual graft survival rates at 1 yr were 87% for CSA-P-AZA-ALG, 80% for CSA-P, and 73% for AZA-P-ALG. The incidence of acute rejection in the 1st yr was similar for CSA-P-AZA-ALG - and CSA-P-treated patients (40% vs 33%), but was lower in both of these groups than in the AZA-P-ALG-treated patients (55%). The 1-yr incidence of infectious complications was 38% for CSA-P-AZA-ALG patients, 30% for CSA-P patients, and 55% for AZA-P-ALG patients. Although the incidence of acute tubular necrosis was not significantly different among the three groups, the duration of oliguria and number of dialyses required were significantly less in the CSA-P-AZA-ALG patients than in the CSA-P patients. Serum creatinine levels at 1 yr posttransplant were lowest in the AZA-P-ALG patients (1.5 ± 0.2 mg/dl), 1.7 ± 0.2 mg/dl for CSA-P-AZA-ALG patients, and 2.0 ± 0.2 mg/dl for CSA-P patients. In summary, our CSA-P-AZA-ALG immunosuppressive protocol for use in cadaveric renal transplantation has achieved its original goal of reducing the adverse consequences of CSA nephrotoxicity by decreasing the duration of acute tubular necrosis and improving creatinine levels while maintaining high patient and graft survival rates.