Background: OKT3 is often used as primary treatment for acute renal allograft rejection. In a retrospective study, we sought to determine the efficacy of OKT3 as a first-line agent in reversing histologically confirmed acute renal allograft rejection.
Methods: Patients with mild to moderate, moderate, or severe acute cellular and acute vascular rejection who had not received any other anti-rejection treatment were included in this analysis. A total of 88 patients, who received OKT3 between 1987 and 1995, fulfilled these criteria.
Result: Seventy of these patients were renal transplant recipients, and 18 were combined kidney and pancreas transplant recipients. The median time to the diagnosis of rejection from transplantation was 32 days (range, 6 days to 13 years). On histology, 6 were graded as mild to moderate, 36 as moderate, 29 as moderate to severe, and 17 as severe rejection. The mean baseline serum creatinine was 1.62 mg/dl (range, 0.7-10.1 mg/dl), and the mean serum creatinine at the time of diagnosis of rejection was 2.60 mg/dl (range, 1.4-12.7 mg/dl) (P=<0.0001). The mean duration of OKT3 treatment was 11.2 days (range, 8-18 days). The mean serum creatinine at the end of OKT3 treatment was 1.73 mg/dl (range, 0.6-5.0 mg/dl; P=0.24 compared with baseline serum creatinine). Rejection was reversed in 86 (98%) patients. Graft survival at 1 year after OKT3 therapy was 87.5% (77 of 88). At a mean follow-up of 38 months, 8 patients had died and 26 grafts were lost. The mean serum creatinine level in the 64 patients with a functioning graft was 1.76 mg/dl (range, 0.8-4.0 mg/dl) at the last follow-up.
Conclusion: OKT3 when utilized as first-line therapy reversed 98% of the acute rejection episodes, with a 1-year post-OKT3 graft survival of 87.5%.