Safety and Effectiveness of Iota-Carrageenan Eye Drops for the Treatment of Dry Eye Disease

Purpose: This clinical investigation evaluated the safety and effectiveness of iota-carrageenan (I-C) eye drops in adults with mild-to-moderate dry eye disease (DED). Methods: In this prospective, single-arm, open-label study, 30 participants applied I-C eye drops three times daily for four weeks. Symptoms (foreign body sensation, burning/stinging, itching, pain, sticky feeling, blurred vision, photophobia) were assessed before and after treatment under both normal controlled environment (NCE) and adverse controlled environment (ACE) conditions. Secondary endpoints included Ocular Surface Disease Index (OSDI), CDES-Q, corneal and conjunctival damage, tear film break-up time, tear evaporation, and tear production. Tolerability was self-reported, while safety (including visual acuity and intraocular pressure) was monitored throughout. Results: After four weeks, mean total DED score decreased significantly by − 11.89 points after ACE (95% CI: − 15.11, − 8.67; p< 0.001) and by − 8.07 points after NCE (95% CI: − 10.71, − 5.43; p< 0.001). Symptom improvement was observed in 93% (ACE) and 89% (NCE) of participants. Mean OSDI score decreased by − 7.75 points (95% CI: − 10.85, − 4.63; p< 0.001). Treatment reduced ACE-induced tear film instability and ocular surface damage. All adverse events were mild and transient; 93% of participants rated tolerability as good or very good. No safety concerns were identified. Conclusion: I-C eye drops are safe, well tolerated, and effective in alleviating DED symptoms, improving tear film stability, and protecting the ocular surface, including under adverse environmental conditions. Trial Registration: NCT06262100.