LONG-TERM OUTCOME OF A PROSPECTIVE RANDOMIZED TRIAL OF CONVERSION FROM CYCLOSPORINE TO AZATHIOPRINE TREATMENT ONE-YEAR AFTER RENAL-TRANSPLANTATION

Background. Since the introduction of cyclosporine (CsA), 1-year renal allograft survival has improved, but concern persists about the long- term adverse effects of CsA, especially with respect to renal function and blood pressure, This randomized controlled trial was set up to es tablish whether withdrawal of CsA would alter long-term outcome. Metho ds. Adult patients who, at 1 year after renal transplantation, had a s table serum creatinine of less than 300 mu mol/L and who had not had a cute rejection within the last; 6 months were eligible for entry. Pati ents were randomized either to continue on CsA (n=114) or to stop CsA and start azathioprine (Aza, n=102), All patients remained on predniso lone, Median follow-up was 93 months after transplantation (range: 52- 133 months), Results. Theres was no significant difference in actuaria l 10-year patient or graft survival (Kaplan-Meier), despite an increas ed incidence of acute rejection within the first few months after conv ersion, Median serum creatinine was lower in the Aza group (Aza: 119 m u mol/L; CsA: 153 mu mol/L at 5 years after randomization, P=0.0002). The requirement for antihypertensive treatment was also reduced after conversion to Ate; 75% of patients required antihypertensive treatment at the start of the study, decreasing to 55% from 1 year after random ization in the Aza group and increasing to >80% in the CsA group (55% (Aza) and 84% (CsA) at 6 years after randomization, P<0.005). Conclusi ons. Conversion from CsA to Aza at 1 year after renal transplantation results in improvement in both blood pressure control and renal allogr aft function, and is not associated with significant adverse effects o n long-term patient or graft survival.