Pharmacokinetic parameters for sirolimus obtained from 19 renal transplant patients receiving microemulsion ciclosporin (4 hours prior to Rapamune) and corticosteroids, following daily doses of 2 mg Rapamune solution in a phase III clinical trial, were; Cmax, ss 12.2 6.2 ng/ ml, tmax, ss 3.01  2.40h, AUC, ss 158  70 ng h/ ml, CL/ F/ W 182 72 ml/ h/ kg (parameters calculated from LC-MS/ MS assay results).