Cyclosporin: a pharmacoeconomic evaluation of its use in renal transplantation

Cyclosporin is a powerful immunosuppressive agent which has markedly improved the outcome of renal transplantation, a technique now well established as the treatment of choice for patients with end-stage renal disease (ESRD). Comparison of cyclosporin-based regimens with a regimen of azathioprine and a glucocorticoid (conventional immunosuppression) indicates an improved clinical course and increased long term graft survival rate with cyclosporin which is most apparent in the recipients of a kidney from a living related donor (human leucocyte antigen mismatched) or cadaver donor source. Cyclosporin has also improved the clinical outcome in patient subgroups previously associated with a higher risk of graft failure with conventional immunosuppression, namely older patients and those with diabetes mellitus. Cost-of-treatment studies conducted over the first post-transplant year in the US have found that higher pharmacy charges with cyclosporin-based regimens are associated with lower hospitalisation charges and total billed charges compared with conventional immunosuppression. Lower hospitalisation charges reflect an improved post-transplant clinical course with cyclosporin and this has been associated with an improved quality of life in the recipients of a cadaver donor kidney. Longer term, the direct cost to society of using cyclosporin-based dual therapy (in combination with a glucocorticoid) may be higher than that with conventional immunosuppression, although the difference is likely to be small compared with the ongoing cost of dialysis. Clinical research continues to focus on modified regimens which maximise the clinical benefits of cyclosporin while minimising the associated adverse events, in particular the potential for nephrotoxicity. Sequential drug therapy (induction with globulin, azathioprine and a glucocorticoid followed by delayed administration of cyclosporin) has been associated with an improved clinical course compared with dual therapy, as well as cost containment to a level comparable to that for conventional immunosuppression. Compared with sequential therapy, triple drug therapy (cyclosporin, azathioprine plus a glucocorticoid) has been associated with a similar clinical course and lower acquisition cost during the first post-transplant year, although its overall impact on the longer term cost of transplantation has yet to be assessed. Elimination of cyclosporin from the immunosuppressive protocol of carefully selected patients can be safely achieved during the first post-transplant year. However, it remains to be established whether savings in the long term acquisition cost of immunosuppression are more than offset by the cost of treating a potentially less favourable clinical course.(ABSTRACT TRUNCATED AT 400 WORDS)