Potential of Fenofibric Acid as Topical Eye Drops for Management of Dry Eye Syndrome

Background/Objectives: Ocular surface inflammation has been identified as a key causative factor for dry eye. The current study investigates the feasibility, safety, and efficacy of fenofibric acid (FFA) as a topical eye drops in controlling ocular surface inflammation. Methods: FFA was tested for its dissolution profile and its cytotoxicity in vitro, and its permeability through ocular surface tissues was tested ex vivo. A safe dose was tested on the Sprague-Dawley (SD) rat eye as an eyedrop for ocular safety and ocular pharmacokinetics. The efficacy was tested on a benzalkonium chloride (BAC)-induced dry eye model in the SD rats. The outcome measurements were analyzed against the untouched contralateral eyes of the animals. Results: The study found that FFA had a similar dissolution profile in PBS (phosphate-buffered saline) as is in saline; however, the saturated concentration in PBS was 81 times higher. FFA had an IC50 (half maximal inhibitory concentration) of 282.4 µM on HCECs (human corneal epithelium cells). The FFA permeation rate for the cornea was 1.77 × 10^-6 µg/cm²/min, 4.95 × 10^-6 µg/cm²/min for the conjunctiva, and 11.32 × 10^-6 µg/cm²/min for the complex of the sclera/choroid. A regimen of twice-a-day eyedrops (500 µg/mL) demonstrated good ocular safety and therapeutic efficacy on the BAC-induced dry eye model in SD rats, with significant effects on the reduction in corneal edema and on preventing the loss of goblet cells from dry eye pathology. Conclusions: These findings strongly suggest that FFA eye drops at a concentration of 500 µg/mL may effectively control ocular surface inflammation and relieve dry-eye discomfort.