Microneedles for Sustained Retinal Drug Delivery

For blinding eye diseases like macular degeneration and diabetic retinopathy, regular drug injections into the eye are the current standard of care. Translational investigators like Yannis Paulus, M.D., are developing alternative ways to administer treatments that are more effective, longer lasting, and less distressing for the patient.

His latest collaboration is with Roland Chen, Ph.D., a fellow pioneer in the development of miniaturized platforms for sustained, localized ocular drug delivery. An expert in biomaterials and biotransport engineering, Dr. Chen, an adjunct faculty member at Kellogg, is an Associate Professor at Washington State University.

Separately, Dr. Paulus developed and continues to test a method to deliver treatment via an array of nanoneedles on a dissolvable contact lens. After delivering their medication, they dissolve. “The nanoneedle platform is a very promising option,” says Dr. Paulus, “but because diverse patients and diseases may respond better to different drug concentrations and penetrations, we need a variety of tools in our toolbox.”

Dr. Chen and Dr. Paulus are developing an alternative that utilizes an array of somewhat larger microneedles.

“The advantage of microneedles is that they can carry larger loads of medicine,” Dr. Paulus explains. “However, they can be too large to dissolve, so another method is needed to attach and remove them. Dr. Chen’s novel solution is to use light.”

Dr. Chen has designed a light-responsive microneedle which swells when exposed to light of a certain wavelength, binding and locking it in place. Shining light of a different wavelength on the microneedles reduces the swelling, allowing them to be removed.

They have received a Peer Reviewed Medical Research Program Expansion Award—Funding Level 3 grant from the U.S. Department of Defense to develop and evaluate their new platform. Studies in their laboratories will validate the technology’s effectiveness, reliability, durability, and safety, and compare the treatment outcomes achieved with the platform’s sustained drug delivery to those of regular intravitreal injections.

Header image caption: Roland Chen, PhD