Plasma concentration of metformin and dexamethasone after administration through Osseogate

Background: Osseogate is a novel drug delivery route through bone marrow involving a modified implant used as the drug delivery system. The purpose of this study was to evaluate the effects of individual drug physicochemical characteristics on the pharmacokinetic behavior when using the Osseogate as administration route. Methods: Implant-mediated drug delivery systems (IMDDS) were installed in a total of 18 rabbits. After complete healing, water-soluble metformin hydrochloride was administered to one group (n = 9) while poorly soluble dexamethasone was administered to the other group (n = 9). The release patterns of each group were monitored for two weeks by measuring the plasma concentration of each drug. Results: Both groups showed relative sustained release. However, metformin hydrochloride showed more rapid diffusion and early termination of drug release compared with dexamethasone. Conclusions: The physicochemical properties of drugs significantly affected the release pattern through Osseogate. Further research is required to achieve controlled delivery using this route.