Concentration-controlled Use of Sirolimus Associated with Reduced Exposure of Cyclosporine in Black Recipients of Primarily Living Renal Allograft Donors: 12-month Results

Aim: This study was designed to identify optimal therapeutic sirolimus (SRL) concentrations in black kidney transplant recipients on reduced cyclosporine (CsA) exposure and prednisone.

Methods: Seventy patients (64 living/six deceased) received CsA (8-10 mg/kg/d), prednisone, and 15 mg loading dose followed by 5-mg fixed doses of SRL till day 7 when they were randomized to maintain SRL trough concentrations (high-performance liquid chromatography) of 8-12 (GI = 34) or 15-20 (GII = 36) ng/mL.

Results: Mean CsA concentrations were 109 +/- 53 vs. 89 +/- 41 ng/mL and 75 +/- 54 vs. 60 +/- 35 ng/mL (ns) at 2 and 6 months. Accordingly, mean SRL trough concentrations were 12.4 +/- 6.1 vs. 20.0 +/- 9.5 ng/mL (p < 0.001) and 10.8 +/- 5.8 vs. 18.0 +/- 6.1 ng/mL (p < 0.001). The incidence of biopsy-proven acute rejection [13% (GI: 18% vs. GII: 8%, ns)], graft loss or death was 16% (GI: 21% vs. GII: 11%, ns]. There were no deaths and three graft losses (GI = 1; GII = 2). Creatinine clearance was higher in GI (64.5 +/- 17 vs. 54.4 +/- 14.7 mL/min, p = 0.011). The incidence of post-transplant diabetes mellitus was 13% and no CMV disease was observed.

Conclusion: In black recipients of primarily living renal allograft donors reduced CsA exposure and SRL concentration-controlled regimens produced low incidences of acute rejection, post-transplant diabetes mellitus and CMV disease, with no significant impairment in graft function.