Researchers in the US have demonstrated for the first time that drugs can be successfully delivered to the eye using microneedles, potentially improving the treatment of diseases such as age-related macular degeneration (AMD).
The scientists – from the Georgia Institute of Technology and Emory University – used tiny microneedles less than 1mm in length to inject drugs into the suprachoroidal space of the eye, showing in animal studies that they could travel to the rear of the eye and deliver compounds to the retina and choroid.
Using the technique the team were able to effectively deliver small-molecule marker compounds as well as Avastin (bevacizumab), an antibody that is used to treat AMD but at present is delivered via intravitreal injection.
“This research could lead to a simple and safe procedure that offers doctors a better way to target drugs to specific locations in the eye,” said Samirkumar Patel, the paper’s lead author and director of research at Clearside Biomedical, a startup formed to commercialise the technology.
Currently, administering drugs to the eye relies on the use of eye drops, which often fail to reach the parts of the eye being targeted, or injection into the vitreous at the centre of the eye.
The latter approach is a necessity for many therapies but has the disadvantage of not targeting specific tissues, requiring frequent dosing, and causing trauma which may lead to a risk of infection.
Moreover, the study found that non-degradeable polymers injected into the suprachoroidal space would travel to the rear of the eye and reside there for up to two months, raising the possibility of developing formulations that could deliver active compounds over an extended period of time.
Henry Edelhauser, a professor of ophthalmology at Emory School of Medicine, said pharmaceutical companies are now developing new compounds to treat eye diseases, and those drugs will be most effective if they can be delivered directly to the portion of the eye that requires treatment.
“With this technique, we are keeping the drug right where it needs to be for most therapies of interest in the back of the eye,” he said.
The study was reported in the July edition of the journal Investigative Ophthalmology & Visual Science.