A new drug delivery approach consisting of an eye patch with detachable microneedles that are able to penetrate the ocular surface may improve therapy results, according to a study published in Nature Communications.

Since ocular barriers often create challenges to drug delivery by topical administration, Singapore researchers created a flexible polymeric eye patch equipped small, detachable needles that act as implanted reservoirs for controlled drug delivery. Investigators say the patch can be readily applied by gentle and brief thumb pressure on the ocular surface, and liken it to the ease of wearing a disposable contact lens without discomfort or the need of extensive skills and training to put on and wear.

“As the micro–drug reservoirs comprise multiple compartments, they allow the release of the same drug with biphasic kinetics or sequentially release of different drugs for synergistic therapy,” they added.

Investigators used corneal neovascularization in mice as the disease model. The study found the delivery of an anti-angiogenic monoclonal antibody (DC101) by the eye patch produced a 90% reduction of the neovascular area with a single treatment of 1µg dosage. In comparison, eye drop applications of DC10—even at a much higher dosage (10µg)—failed to show significant therapeutic effect, researchers noted.

Researchers suggested their drug delivery approach could work for other eye diseases as well. These could include delivery of β-adrenergic receptor blockers or prostaglandin analogues for glaucoma, corticosteroids for anterior uveitis and fluconazole for fungal keratitis. Their eye patch system could also be used for intracorneal delivery of riboflavin to patients with keratoconus without the need of corneal epithelial scraping and debridement, which could avoid postoperative pain, infection and permanent damage often associated with traditional surgical methods, researchers said.

“In summary, the demonstrated microneedle eye patch, which implants micro-drug-reservoirs for localized, controlled and efficient ocular drug delivery in a convenient, safe and painless manner, provides a cost-effective and home-based solution for many ocular diseases,” researchers said.

Than A, Liu C, Chang H, et al. Self-implantable double-layered micro-drug-reservoirs for efficient and controlled ocular drug delivery. Nat Commun. 2018 Nov 6;9(1):4433.