London: Drugs used to treat blindness-causing disorders could be successfully administered by eye drops rather than unpleasant and expensive eye injections, according to new research. The study led by University College London (UCL) scientists could be a breakthrough for the millions worldwide suffering from age-related macular degeneration (AMD) and other eye disorders, researchers said. One in 5 people over 75 have AMD with well-known sufferers, researchers said. The findings are significant due to growing patient numbers and an increasing demand for the eye injections that halt the progression of the disease.

The study, in animal models, demonstrates that it is possible to create formulations of tiny nanoparticles loaded with the AMD drug Avastin and deliver significant concentrations to the back of the eye. "The development of eye drops that can be safely and effectively used in patients would be a magic bullet - a huge breakthrough in the treatment of AMD and other debilitating eye disorders," lead author Professor Francesca Cordeiro said. "The current treatment of injecting drugs into the eye is uncomfortable, detested by patients and often needs repeated monthly injections in hospital for as long as 24 consecutive months. It's impossible to exaggerate the relief patients would feel at not having to experience injections into their eyes," said Cordeiro.

Effective delivery of drugs to the retina of the eye is considered one of the most challenging areas in drug development in ophthalmology, due to the presence of anatomical barriers. It was previously thought that drugs used to treat AMD such as Avastin and Lucentis have molecules that are simply too large to be effectively transported in an eye drop. "There is significant interest in the development of minimally invasive systems to deliver large drug molecules across biological barriers including the cornea of the eye," first author Dr Ben Davis added.