31 Aug Drug dispensing contact lenses to treat glaucoma
Drug-dispensing contacted lenses could offer new hope to people suffering from glaucoma, which causes blindness, after they were found to be at least as effective as eye drops.
Researchers say that the lens, which is designed to deliver medication gradually, may improve the treatment of patients who struggle with eye drops, which can be imprecise and difficult to self-administer.
It is estimated that more than 500,000 people in England and Wales have glaucoma, a build-up of pressure on the eye, but many more people may suffer from the condition without having been diagnosed.
Doctor Joseph Ciolino, an ophthalmologist at Harvard Medical School, said: “We found that a lower-dose contact lens delivered the same amount of pressure reduction as the latanoprost drops, and a higher-doselens, interestingly enough, had better pressure reduction than the drops in our small study.
“Based on our preliminary data, the lenses have not only the potential to improve compliance for patients, but also the potential of providing better pressure reduction than the drops.”
Glaucoma is the leading cause of irreversible blindness in the world.
While there is no cure for the condition, medications are designed to lower pressure in the eye with the goal of preventing vision loss.
Currently, the medications are delivered in the form of eye drops, which sometimes cause stinging and burning.
Contact lenses have been studied as a means of drug delivery for nearly 50 years, yet many such lenses are ineffective because they dispense the drug too quickly.
The researchers behind the new study designed the contact lens to allow for a more controlled drug release by using a tiny film of drug-encapsulated polymers in the periphery, which slows the drug coming out of the lens.
Because the drug film is on the periphery, the centre of the lens is clear, allowing for normal visual acuity, breathability and hydration.
The drug-dispensing lens can also be designed to do the traditional job of correcting eye sight where necessary.
The researchers are currently designing clinical trials to determine the safety and efficiency of the lenses in humans.
Dr Ciolino said: “If we can address the problem of compliance, we may help patients adhere to the therapy necessary to maintain vision in diseases like glaucoma, saving millions from preventable blindness.
“This study also raises the possibility that we may have an option for glaucoma that’s more effective than what we have today.”