Reassessment of Tigecycline Bone Concentrations in Volunteers Undergoing Elective Orthopedic Procedures

The goal of the this study was to re-evaluate tigecycline bone concentrations in subjects undergoing elective orthopedic surgery, using multiple doses and a more robust bone assay than was used in a previous study. Each subject received three intravenous doses of tigecycline (one 100-mg infusion followed by two 50-mg infusions, each administered over 30minutes). A single bone sample was collected from each subject at one of the following times: 1, 2, 4, 6, 8, or 12hours after the third dose. Four blood samples were collected from each subject: before the first dose, before and after the third dose, and within 15minutes of the collection time of the bone sample. Noncompartmental pharmacokinetic analysis serum and bone area under the curve for the given dose interval (AUC) values were 2,402ngh/mL and 11,465ngh/g, and maximum concentration (C-max) values were 974ng/mL and 2,262ng/g, respectively. The bone to serum ratio calculated using the AUC values was 4.77, confirming tigecycline penetration into bone.