Efficacy of polyethylene glycol–propylene glycol-based lubricant eye drops in reducing squamous metaplasia in patients with dry eye disease

Abstract

Purpose: Squamous metaplasia in dry eye disease (DED) manifesting as the loss of conjunctival goblet cells results in reduced mucin secretion and tear film instability. The objective of this study was to evaluate the efficacy of a polyethylene glycol–propylene glycol/hydroxypropyl-guar (PEG-PG/HP-guar) artificial tear formulation in reducing the squamous metaplasia in patients with DED using conjunctival impression cytology (CIC). Methods: In this Phase IV, single-arm, open-label study, DED patients (aged ≥18 years) with a corneal staining sum score ≥3 and tear film break-up time (TFBUT) <7 s self-administered the PEG-PG/HP-guar artificial tears, 3 times a day for a period of 90 days. The primary end point was the change from baseline in goblet cell density (Nelson’s CIC grading score) over the treatment period. Other end points were change in the corneal and conjunctival staining scores, and TFBUT. Statistical evaluation was performed using a paired t-test. Results: In total, 49 patients (n=98 eyes) completed the study. Compared with baseline, there was a significant reduction in the mean CIC scores (ie, improvement in goblet cell density) at Days 30, 60, and 90 (1.6±0.5 vs 1.2±0.5, 0.9±0.5, and 0.8±0.5; P<0.0001). At Day 90, 22% of eyes demonstrated squamous metaplasia Grade 0 (ie, normal epithelium). Similar improvements were observed in the corneal staining scores (5.7 vs 3.1, 1.1, and 0.5; P<0.0001), conjunctival staining scores (5.5 vs 3.6, 1.6, and 0.9; P<0.0001), and TFBUT (4.8 vs 5.8, 6.3, and 6.8 s; P<0.0001) at Days 30, 60, and 90, respectively. Conclusion: In this study, treatment with PEG-PG/HP-guar artificial tears for 90 days decreased CIC score, reduced corneal and conjunctival staining, and increased TFBUT in patients with DED. These results suggest that PEG-PG/HP-guar artificial tears can improve the ocular surface health and reverse the changes induced by squamous metaplasia in DED.