Efficacy of eyedrops containing cross-linked hyaluronic acid and coenzyme Q10 in treating patients with mild to moderate dry eye

Purpose: Dry eye disease (DED) is a common condition causing substantial burden. A randomized, controlled, single-masked study was performed in 40 patients with mild to moderate DED to evaluate the efficacy and safety of a collyrium based on crosslinked hyaluronic acid (XLHA) with coenzyme Q10 (CoQ10). Methods: Enrolled subjects were divided into 2 groups: group A, treated with XLHA + CoQ10; and group B, treated with hyaluronic acid (HA). Eyedrops were administered 4 times daily for 3 months. The Ocular Surface Disease Index (OSDI) questionnaire, tear break-up time (TBUT), corneal and conjunctival staining, and meibomian gland assessment (MGD) were evaluated; furthermore, corneal aesthesiometry, in vivo corneal confocal microscopy, visual acuity, intraocular pressure (IOP), and fundus examination were performed. Results: At the end of treatment, OSDI score significantly decreased in groups A and B (p<0.01 and p<0.05, respectively); the decrease was significantly higher in group A. Corneal staining decreased in both groups, with lower scores in group A. The MGD was significantly ameliorated in group A patients. No differences were found for corneal aesthesiometry or TBUT. Epithelial cell reflectivity was significantly reduced only in group A. For keratocytes and stromal matrix parameters, there was a significant improvement in group A. No changes were found for visual acuity, IOP, or fundus examination. Conclusions: The XLHA + CoQ10 treatment showed greater effectiveness in DED compared to HA alone, probably due to the longer permanency on ocular surface and the antioxidant activity of CoQ10. Therefore, XLHA + CoQ10 eyedrops could represent a new possibility in dry eye treatment.