Targeted liposomal delivery of cGMP analogues

The invention relates to means and methods of targeted drug delivery of therapeutic agent to and across the blood-ocular barrier. In particular, the invention relates to cyclic guanosine-3', 5 '-monophosphate analogues as therapeutic agent for treating retinal diseases. The cGMPSs targeted to the blood-ocular barrier by glutathione-based ligands that facilitate the specific binding to and enhanced internalization by glutathione transporters present on the blood-ocular barrier. The glutathione-based ligands are conjugated to nanocontainers such as liposomes encapsulating the cGMPSs.