Preclinical and clinical evaluation of an ocular nanoemulsion for the treatment of dry eye disease

BACKGROUND: The efficacy, safety, and ocular retention of a novel preservative-free nanoemulsion eye drop formulation (VSLB) containing castor oil and sodium hyaluronate for dry eye disease (DED) were evaluated. RESEARCH DESIGN AND METHODS: A preclinical evaluation using a scopolamine-induced dry eye rat model and a prospective, randomized, double-masked clinical study involving 64 human subjects with moderate-to-severe DED were conducted. Tear film breakup time (TFBUT), ocular surface disease index (OSDI), Meibomian gland assessment, and pre-ocular residence time were measured. RESULTS: VSLB significantly improved TFBUT from <2 s on day 2 to 10.83 ± 1.5 s at day 28, comparable to marketed product and healthy controls in rats. Ocular residence time for VSLB remained detectable in 3 out of 6 animals, compared to 0 in placebo. In the clinical phase, mean TFBUT in the VSLB group increased from 4.26 ± 2.14 s (baseline) to 6.36 ± 2.73 s at day 15 and 6.00 ± 2.93 s at day 30. The OSDI score, the Meibomian gland expressibility score, and secretion quality were also improved. No serious adverse events were reported. CONCLUSION: VSLB demonstrated a promising therapeutic profile by tear-film stabilization and symptomatic relief. Its preservative-free, lipid-enhancing formulation with prolonged ocular residence suggests a safe and effective treatment option for DED. TRIAL REGISTRATION: Clinical trial registration: www.clinicaltrials.gov identifier is NCT06323395.