A Novel Eye Drop Candidate for Age-Related Macular Degeneration Treatment: Studies on its Pharmacokinetics and Distribution in Rats and Rabbits

Age-related macular degeneration (AMD) is wearing down of macula of retina, causing a blur or loss of vision in the center of the visual field. It can be categorized into dry or wet AMD. Until now, medical treatments for dry AMD have not been developed yet. The aim of this study was to evaluate pharmacokinetics (PKs) and tissue distribution of CK41016, a novel candidate for dry AMD, after intravenous (IV) or eye drop administration in rats and rabbits. In addition, a simple and sensitive bioanalytical method for CK41016 using ultra performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS) was developed. PK parameters were estimated by compartmental analysis using a WinNonlin(®) software version 8.1 (a Certara™ company). A PK model of CK41016 was well-described by the two-compartment model. The tissue-to-plasma partition coefficient (Kp) of CK41016 was the highest in the vitreous humor of rats and the cornea of rabbits after eye drop administration. In addition, the Caco-2 cell transporter assay confirmed that CK41016 was not an active substrate for the efflux transporter. In summary, the PKs and tissue distribution of CK41016 were successfully evaluated and investigated whether this drug was a substrate of efflux transporters.