Beneficial effect of thalidomide and ciclosporin combination in heterotopic cardiac transplantation in rats

The effect of thalidomide on the prevention of early rejection was studied in heterotopic cardiac transplants between ACI (donors) and Lewis (recipient) rats, in combination with subtherapeutic doses of ciclosporin. Although allografts treated solely with thalidomide (5 mg/kg/day intraperitoneally) survived longer than controls (9.4 ± 2.7 and 6.3 ± 0.6 days, respectively, p <0.001), the survival rates of animals treated with low dose ciclosporin (1.25 mg/kg/day intraperitoneally) plus thalidomide (1.25, 2.5 and 5 mg/kg/day) were significantly better at 21 days (70, 88.9 and 88.9%, respectively), compared to 55.6% in those treated with ciclosporin (1.25 mg/kg/day) alone. Graft survival rates at 90 days were not significantly different in the thalidomide-ciclosporin combination groups (60,77.8 and 55.6%, respectively) compared to the ciclosporin group alone (55.6%). We conclude that thalidomide is effective in preventing early rejection of rat cardiac allograft when combined with subtherapeutic doses of ciclosporin, thus avoiding the dose-dependent side effects of ciclosporin in the early posttransplant period.