Single dose pharmacokinetics of ciclosporin and its main metabolites after oral ciclosporin as oily solution or capsule.

The commercially available oily solution of ciclosporin which has to be suspended before intake is disliked by some patients for bad taste and has a variable bioavailability. In this investigation the oral pharmacokinetics of ciclosporin and its main metabolites 1 and 17 of the oily solution (Sandimmun) and a soft gelatine capsule preparation of ciclosporin were compared in a crossover fashion in 10 kidney allograft recipients. The results demonstrate a bioequivalence of both formulations. In either case metabolite 17 had a significantly longer half-life than either ciclosporin or metabolite 1. At earlier time-points the concentration of ciclosporin could be best correlated with metabolite 1 and at later time-points with metabolite 17. Both metabolites were less correlated with each other in the late absorption phase of ciclosporin.