Liposome-bound cyclosporine: clearance after intravitreal injection.

The concentration of cyclosporine in the vitreous after intravitreal injection of 100 micrograms of either free or liposome-bound cyclosporine was studied in albino rabbits. We found that the half-life of free cyclosporine was about 6 hours and that of liposome-bound cyclosporine was about 3 days. The finding indicates that liposome-bound cyclosporine prolongs the availability of the drug.