A drug-delivering bandage contact lens that simultaneously treats the eye and allows it to heal faster has been developed by a cross-disciplinary team at University of Waterloo in Canada.

Typically, corneal abrasion patients spend seven to 10 days wearing a clear, oxygen-permeable bandage contact lens, often instilled with eye drops containing antibiotics. However, the one-time antibiotic application makes it difficult to ensure enough drugs stay on the eye for sustained treatment.

“It’s a targeted-release drug delivery system that is responsive to the body,” said Dr Lyndon Jones, a professor at Waterloo’s School of Optometry and Vision Science and Director of the Centre for Ocular Research and Education (CORE). “The more injured you are, the more drug gets delivered, which is unique and potentially a game changer.”

Dr Jones teamed up with Dr Susmita Bose, Dr Chau-Minh Phan and Dr Evelyn Yim. Rounding out the team were Dr Muhammad Rizwan, a former postdoctoral fellow, and John Waylon Tse, a former graduate student, both with Dr Yim’s lab.

WORKING WITH COLLAGEN

Collagen is a protein naturally found in the eye that’s also often involved in the wound healing process – however, it’s too soft and weak to be a contact lens material. Dr Yim, an associate professor of chemical engineering working on collagen-based materials, found a way to transform gelatin methacrylate, a collagen derivative, into a biomaterial 10 times stronger.

One unique property of collagen-based materials is that they degrade when exposed to an enzyme called matrix metalloproteinase-9 ( MMP-9), which is naturally found in the eye.

“These enzymes are very special because they ’re involved in wound healing , and when you have a wound, they ’re released in greater quantity,”

Dr Phan said. “If you have a material that can be degraded in the presence of this enzyme, and we add a drug to this material, we can engineer it, so it releases the drug in a way that is proportional to the amount of enzymes present at the wound. So, the bigger the wound, the higher the amount of drug released.”

The team used bovine lactoferrin as a model wound-healing drug and entrapped it in the material. In human cell culture study, the researchers achieved complete wound healing within five days using the drug-releasing novel contact lens material.

Another benefit of the material is that it only becomes activated at eye temperatures, providing an inbuilt storage mechanism.

The next step is to fine-tune the material, which will include entrapping different drugs in it.

The scientists believe their material has great potential – not only for the eye but potentially for other body sites, especially large skin ulcers.

A study outlining the researchers’ work was recently published in the journal Pharmaceutics.1

Reference 1. Bose, S., Phan, C-M., Jones, L., et al., Fabriation and characterization of an enzyme-triggered, therapeutic releasing hydrogel bandage contact lens material, Pharmaceutics, 2024.16(1),26. DOI: 10.3390/pharmaceutics16010026.