Antithymocyte globulin (ATGAM) in renal allograft recipients. Multicenter trials using a 14-dose regimen.

Antithymocyte globulin (ATG, ATGAM; The Upjohn Company) was tested for efficacy and safety in controlled studies in 358 renal allograft recipients. A total of 183 patients were treated according to protocols prescribing 14 daily doses of ATG in addition to standard immunosuppressive therapy with azathioprine and prednisone, while 175 controls received no ATG. Four ATG lots were tested; results with each lot were analyzed separately, and the data were also pooled to obtain an overall impression. ATG delayed the onset of the first rejection episode during the prescribed treatment period (2 weeks). Concurrently, less i.v. steroid was required, but the steroid dosage requirement then rebounded in the 2 weeks after the end of the prescribed treatment period. ATG did not significantly improve the proportion of patients alive with functioning grafts 6 months after transplant, except with one of the four lots.