Contact lenses as sight-saving drug delivery system

A drug-dispensing contact lens has shown success in effectively lowering eye pressure in monkeys with induced glaucoma. In what is termed a ‘pre-clinical model’, the study found that the medication, latanoprost, usually administered by the patient in conventional eye drops, in the contact lens form had equal or better intraocular pressure reduction. To quote the study’s first author, “We found that a lower-dose contact lens delivered the same amount of pressure reduction as the latanoprost drops, and a higher-dose lens, interestingly enough, had better pressure reduction than the drops in our small study,” said Joseph B. Ciolino, M.D., an ophthalmologist at Massachusetts Eye and Ear and an Assistant Professor of Ophthalmology at Harvard Medical School. The design of the lens does double duty: the periphery contains the thin film of drug-encapsulated polymers that slowly releases the drug; the center of the lens is clear and breathable, thus usable for standard vision correction.

Contact lenses for drug delivery have been for decades intriguing to researchers, but the embedded drug delivery has been too rapid to be effective in most cases; thus the polymers and the design are critical in slowing delivery. In glaucoma, both compliance and dosing the correct amount over time are critical to successfully lowering intraocular eye pressure and preserving sight. The Telegraph notes that 500,000 people in England and Wales have been diagnosed with glaucoma, and the value for those who find it difficult or not possible to self-administer. The research is being supported by Massachusetts Eye and Ear Hospital, Boston Children’s Hospital and Harvard Medical School Department of Ophthalmology.  Newswise (release), Ophthalmology (AAO Journal, full text)

Related: Sensor-based research utilizing contact lenses in diabetic glucose detection has been most recently from Alphabet (Google) partnering with Novartis/Alcon [TTA 27 Mar 15] and Samsung’s contact lens camera dubbed ‘Gear Blink’ last April. Going back a little further and closely related, Switzerland’s Sensimed Triggerfish developed a soft contact lens for long-term (up to 24 hours) active measurement of intra-ocular pressure in glaucoma [TTA 31 July 13].