Cardiovascular risk factors of sirolimus compared with cyclosporine: early experience from two randomized trials in renal transplantation

Abstract

Introduction Renal transplant recipients are at a higher risk of cardiovascular events, including death. This paper examines cardiovascular risk factors in two phase II studies comparing cyclosporine (CsA) with sirolimus-based therapy. Methods In two phase II studies, patients ( n = 161) were randomized at the time of transplantation to receive either sirolimus or CsA in triple-therapy regimens with either azathioprine (Study A) or mycophenolate mofetil (Study B), and corticosteroids. Sirolimus whole blood trough levels were targeted to 30 ng/mL for 2 months and 15 ng/mL thereafter. Pooled results of the two studies are reported. Results When patients receiving sirolimus were compared with those receiving CsA, peak cholesterol and trigylcerides at 2 months were markedly and significant higher with sirolimus therapy. The difference between groups decreased thereafter and was not significant from 12 through 24 months. Control of lipid parameters in sirolimus-treated patients was achieved by decreasing the target trough levels after 2 months and by using lipid-lowering agents. Sirolimus-based therapy was associated with a lower incidence of treatment-emergent hypertension (47.5% vs 29.6%, P < .024). At 24 months, the calculated glomerular filtration rate was significantly better with sirolimus (51.3 vs 65.1 mL/min, P < .001). There were no significant differences in the incidences of diabetes or death due to cardiovascular events. Conclusion Patients receiving sirolimus experience an initial increase in lipid levels, but these effects are manageable with the use of lipid-lowering agents. Hypertension was less frequent and renal function was improved with CsA-free, sirolimus-based therapy. Based on this early experience, overall cardiovascular risk does not appear to be increased with sirolimus-based compared with CsA-based therapy.