Effects of Netarsudil and Latanoprost Alone and in Fixed Combination on Corneal Endothelium and Corneal Thickness: Post-Hoc Analysis of MERCURY-2

INTRODUCTION: To describe the changes in endothelial cell density (ECD), the coefficient of variation (CV), the percentage of hexagonal cells (%HEX), and central corneal thickness (CCT) following 3 months of therapy with netarsudil 0.02%/latanoprost 0.005% fixed combination, and to compare these changes with those seen with netarsudil 0.02% or latanoprost 0.005% in eyes with ocular hypertension or open-angle glaucoma. METHODS: A subset of subjects enrolled in a Phase 3 evaluation of the intraocular pressure-lowering efficacy and safety of netarsudil 0.02%/latanoprost 0.005% fixed combination once daily (QD) versus each of its individual components underwent corneal endothelial cell imaging by specular microscopy and ultrasound pachymetry at baseline and following 3 months of therapy. Images were evaluated in masked fashion at an independent reading center. Changes from baseline to 3 months in ECD, CV, %HEX, and CCT were compared between treatment groups. RESULTS: Data from 415 subjects obtained at both baseline and Month 3 were included in this post hoc analysis. Changes from baseline to Month 3 in ECD, CV, and %HEX were clinically insignificant in all three groups, and the changes in the netarsudil/latanoprost fixed combination group demonstrated no statistical difference from those seen in the netarsudil and latanoprost groups. Mean CCT decreased more in the fixed combination group (− 6.4 µm) than in either the netarsudil group (− 3.3 µm, p = 0.0248) or the latanoprost group (− 1.2 µm, p < 0.0001). CONCLUSIONS: Netarsudil 0.2%/latanoprost 0.005% fixed combination QD for 3 months in eyes with ocular hypertension or open-angle glaucoma had no clinically significant effects on endothelial cell density or morphology. The significant decrease in CCT in the fixed combination group compared to the two individual component groups may indicate that the potential effects of each drug on CCT are additive, although the magnitude of the observed effects is likely of negligible clinical significance. CLINICALTRIALS.GOV IDENTIFIER: NCT02674854.