Long-term management of dry eye by once-daily use of Chitosan-N-Acetylcysteine (Lacrimera®) eye drops.

Purpose: To evaluate the tolerability, safety and performance of chitosan-N-acetylcysteine (CNAC) eye drops in patients with mild-to-moderate dry eye disease after long-term once-daily use. Methods: This prospective, non-comparative, multicenter trial comprised a 2-week run-in phase (concomitant use of hyaluronic acid eye drops allowed), a 4-week main phase, and a voluntary 20 week long-term safety follow-up (LTSFU). Assessments (improvement in dry eye symptoms, Ocular Surface Disease Index (OSDI), matrix metallopeptidase 9 (MMP-9) status, tear film break-up time (TBUT), corneal staining) were made bi-weekly up to Week 6 and every four weeks thereafter. Results: Out of 102 patients included, 80 entered and 77 (96%) completed the main phase, 48 joined the LTSFU and 31 (65%) completed 26 weeks of treatment. Compared to baseline, both the dry eye symptoms intensity score and the Ocular Surface Disease Index were reduced by 55% and 47%, respectively at week 6 and by 67% (right eye) and 78% (left eye) and 70% at Week 26, respectively (p<0.0001). The tear film break-up time increased by ∼15% (p<0.05) at Week 6. Matrix metallopeptidase-9 shifted to negative in 59% of eyes and conjunctival or eyelid abnormalities disappeared in ∼30%. Most common AEs were eye irritation, blurred vision, foreign body sensation and corneal staining. Global treatment satisfaction was ∼80% at Weeks 6 and 26, compared to 65% for previous treatment before entering the study. Conclusion: Once-daily use of C-NAC eye drops is a highly effective and convenient treatment option for dry eye disease. C-NAC can be safely used long term.