title: Reduced inter- and intraindividual variability in cyclosporine pharmacokinetics from a microemulsion formulation.
abstract: The inter- and intraindividual variability of cyclosporine pharmacokinetics from a microemulsion formulation were compared with the currently marketed formulation in a sequential bioreplication study. Twenty-four healthy male volunteers were randomized to receive each formulation on two separate occasions; the reference treatment was a single oral dose of 300 mg of Sandimmune and the test treatment was a single oral dose of 180 mg of Sandimmune Neoral, both given as soft gelatin capsules. Serial venous blood samples were obtained over a period of 48 h after each administration, and cyclosporine concentrations were measured in whole blood by a specific monoclonal RIA method. Between- and within-subject variabilities were quantified from the appropriate sums of squares from analysis of variance and statistically compared between formulations. Both inter- and intraindividual variation for the peak concentration, time to reach the peak, area under the curve, and terminal half-life of the test formulation were significantly reduced (p < 0.05) with two exceptions. For area under the curve between subjects (p < 0.2) and peak concentration within subjects (p < 0.1), trends toward reduced variability for the test formulation were evident. These results were further reflected in the inter- and intraindividual coefficients of variation of the pharmacokinetic parameters that ranged from 3 to 22% for the test formulation compared with 19 to 41% for the reference formulation. In comparison with the currently marketed formulation, reduced variability in the pharmacokinetics of cyclosporine following oral administration of Sandimmune Neoral provides a more predictable and consistent concentration-time profile.
authors.affiliation: Department of Human Pharmacology, Drug Safety Assessment, Sandoz Pharma, Ltd., Basle, Switzerland.
authors.forename: J M
authors.initials: JM
authors.lastname: Kovarik
authors.forename: E A
authors.initials: EA
authors.lastname: Mueller
authors.forename: J B
authors.initials: JB
authors.lastname: van Bree
authors.forename: W
authors.initials: W
authors.lastname: Tetzloff
authors.forename: K
authors.initials: K
authors.lastname: Kutz
mesh_terms: D000328:Adult; D000911:Antibodies, Monoclonal / Q000032:analysis; D016572:Cyclosporine / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D004655:Emulsions; D006207:Half-Life; D006801:Humans; D008297:Male; D011863:Radioimmunoassay
chemical_list: D000911:Antibodies, Monoclonal; D004655:Emulsions; D016572:Cyclosporine