University of Pittsburgh

Novel Non-Invasive Eye Medication Delivery System

University of Pittsburgh scientists have developed a novel thermoresponsive hydrogel containing polymer nanoparticles to deliver eye medications of interest in a non-invasive and sustained manner. This gel, designed to be applied directly to the eye, can deliver medication over days or months acting as a “monthly eye drop” removing the need for regular invasive use of eye medication which is often a cause of discomfort and distress.  

Description

Designed with two key components, the thermoreponsive gel can be used to securely deliver a variety of medicinal agents using a polymer microparticle including proteins, antibodies or peptides directly to the eye over a fixed period. Modification of the polymer microparticle could regulate the timeframe over which a therapeutic agent is released. This long-term drug release could improve treatment strategies for various eye diseases allowing for one single application of medication per month.

Applications

• Chronic eye conditions (e.g., glaucoma or chronic dry eye)
• Acute eye conditions including conjunctivitis, bacterial infections and keratitis
• Drug delivery over an extended period

Advantages

At present, microparticles or hydrogels for eye conditions must be injected directly into the anterior chamber or vitreous (gel-like fluid in the eye) by a clinician and is a highly invasive and uncomfortable procedure. Alternatively, topical eye drops can be used, but effects last for only a few hours and these require regular administration to be effective.
This novel hydrogel and polymer microparticle combination is designed to be non-invasive, suitable for patient self-administration to the lower fornix (beneath the lower eyelid) and easily removed by the patient using tweezers or saline solution. The microparticle can be tailored to control slow release of the therapeutic agent. A key advantage is the thermoresponsiveness of the hydrogel. It can be administered easily with a plunger to the lower fornix, and upon contact with body temperature a gel is formed, molded to the shape of the patient’s conjunctival cul de sac. This gel can be manipulated with tweezers and removed from the eye either at the end of the required treatment period or when replaced by the next dose.

Invention Readiness

A suspension has been developed containing a poly(lactic-co-glycolic) acid polymer microparticle suspended in a poly-N-isopropylacrylamide (pNIPAAm) hydrogel. While the suspension is clear at room temperature, it forms an opaque, solid gel above 34 C. In small scale animal studies, either standard therapy (repeated drops of Vigamox®), a hydrogel containing moxifloxacin (MOX-HG), or a control (blank) hydrogel was administered to eyes infected with Staphylococcus aureus (E253). Animals treated with Vigamox® and MOX-HG showed no clinical or microbiological signs of endophthalmitis, unlike those treated with the control hydrogel only. Further work to explore the effectiveness of this treatment in humans is required.

IP Status

https://patents.google.com/patent/US11246838B2