Cyclosporine as a milestone in immunosuppression.

In this short review I show how cyclosporine fits into the broader picture of immunosuppression for organ allografting. Before cyclosporine there were some good results, particularly in kidney grafting, but also a failure rate of 50% of grafts by 1 year. Cyclosporine changed the graft survival of 1 year to 80%, although at 10 years the graft survival was little different from patients treated with azathioprine and steroids. Nevertheless, many patients achieved good function in their kidneys when treated with cyclosporine; these patients would have lost the kidneys under the old regimen. The cause of the late failure in patients treated with cyclosporine was predominantly nephrotoxicity due to the calcineurine inhibition, damaging the kidneys. Now that this is better understood and new drugs are available, many regimens have been tried but cyclosporine remains an important tool for the clinician in the treatment of patients with organ allografts.