Abstract
Purpose :
Post-traumatic corneal stromal ulceration is painful and potentially sight-threatening, and thus a topical treatment that increases the rate of ulcer healing would be a valuable addition to the ophthalmic therapeutic armamentarium. A proprietary crosslinked HA gel, containing 0.75% thiolated carboxymethylHA (CMHA-S), (Remend, Bayer UK, JDE-003) was evaluated for safety in rabbits and efficacy in two randomised masked studies comparing time to complete healing of corneal stromal ulceration in dogs and in cats given alternatively a standard HA tear replacement drop (0.3% HA; HATRD).
Methods :
New Zealand white rabbits were dosed topically 6X per day with CMHA-S (6 animals) or HATRD (6 animals), for 28 days and examined for inflammation, corneal thickness, and systemic toxicity. 30 dogs and 30 cats, diagnosed with naturally occurring corneal stromal ulceration, were randomized into two groups of 15 for each species, one treated with CMHA-S and the other treated with HATRD the study being double masked. Animals with ocular surface infection or symptoms of keratoconjunctivitis sicca were excluded from the study. Animals were examined clinically by direct and indirect ophthalmoscopy and by slit lamp biomicroscopy,with ulcer presence evaluated byfluorescein staining. Time to ulcer healing of each treatment group was documented.
Results :
Rabbits receiving 28 days of 6x/day therapy of either treatment demonstrated no signs of inflammation, change in corneal thickness, or system toxicity clinically or on histopathology. Feline ulcers treated with CMHA-S healed in 21.0±11.0 days while those treated with HATRD healed in 31.8±10.3 days (p<0.02). Canine ulcers treated with CMHA-S also healed significantly faster (14.8±4.1 days) than those treated with HATRD(18.3±4.9 days)(p=0.04).
Conclusions :
These results indicate that the crosslinked HA gel, delivered topically to the eye, is safe and well tolerated. Further, in spontaneously occurring corneal ulceration in pet dogs and cats, our resultsdemonstrate thatthe CMHA-S gel is associated with more rapid healing than treatment with a noncrosslinked HA solution. This crosslinked HA is currently being developed for human clinical use by Jade Therapeutics.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.