Effects of Netarsudil on the Corneal Endothelium

The Multifarious Effects of Various Glaucoma Pharmacotherapy on Corneal Endothelium: A Narrative Review

Corneal endothelium is a single cell layer that is mainly responsible for maintaining corneal clarity. Endothelial damage secondary to toxicity, stress, or genetic predisposition are common and in conjunction with the low regenerative ability of the cells, making their preservation critical for maintaining visual acuity. Patients with glaucoma, who are estimated to be close to 80 million worldwide, have a plethora of reasons for developing endothelial damage, being exposed to a spectrum that extends from various medical and surgical interventions to the disease itself. The wide spectrum of glaucoma pharmacotherapy that has been recently extended by addition of newer classes of medications has been the focus of extensive research on its effects on corneal endothelium. Both basic and clinical research have attempted to shine a light on the complex mechanisms associated with the effects of glaucoma medication on corneal endothelium and to answer the important question as to whether these findings are clinically significant. The aim of this review is to summarize and present current literature of the various findings, both from in vivo and in vitro studies that have focused on the complex relationship between different classes of glaucoma medication and their effect on corneal endothelium.

"Rapid and reversible alteration in corneal contour and power associated with Netarsudil/Latanoprost"

Purpose

To describe a previously unreported case of reversible myopic shift with corresponding changes in corneal contour in a patient treated with netarsudil/latanoprost.

Observations

A 72-year-old male with history of primary open angle glaucoma, prior cataract surgery, and remote radial keratotomy surgery was treated with fixed-dose combination of netarsudil/latanoprost. Despite no prior history of refractive shift in the twenty years since radial keratotomy surgery, on one month follow-up, he reported reduced visual acuity and presented with approximately 1.50 D shift in both eyes. There were associated corneal contour changes. No corneal epithelial bullae or edema were appreciated. Netarsudil/latanoprost was discontinued and timolol was initiated. One month later, both refractive error and corneal contour returned to prior levels.

Conclusions

Netarsudil is a rho-kinase and norepinephrine transporter inhibitor that may be effective in the treatment of primary open angle glaucoma resistant to other topical treatments. In addition to corneal epithelial bullous edema previously reported, this drug may induce reversible changes in corneal contour in patients with prior corneal or refractive surgery.

The effectiveness and safety profile of netarsudil 0.02% in glaucoma treatment: real-world 6-month outcomes

PURPOSE

To evaluate the efficacy and safety profile of netarsudil 0.02% ophthalmic solution in a tertiary glaucoma referral center.

METHODS

This retrospective cohort study included patients with glaucoma initiated on netarsudil 0.02% at a single institution from November 2017 to September 2018. Demographic and clinical data were collected, including intraocular pressure (IOP) and drug side effects at baseline and 1-, 3-, and 6-month follow-up visits.

RESULTS

A total of 340 eyes of 233 patients were included; mean ± SD patient age was 69.1 ± 12.5 years. One hundred twenty (48%) eyes experienced ≥ 20% decreases in IOP at the 1-month study visit; this effect was maintained through the 6-month visit. IOP-lowering effects in patients using ≥ 3 topical glaucoma medications were similar (all p > 0.1). Eighteen (7.4%) and 7 (2.9%) patients experienced increases in IOP of ≥ 3 and ≥ 5 mmHg, respectively. Across all study visits, conjunctival hyperemia was noted at a rate of 27.6%, and though frequently reported, complaints of blurred vision (31.1%) did not manifest in significant worsening of visual acuity. The rate of drug discontinuation due to insufficient IOP-lowering and side effects was 15.6% and 24.8%, respectively. Twenty-nine (11.4%) and 82 (32.3%) eyes required additional medical and surgical/laser intervention, respectively.

CONCLUSION

Commonly used as the last-line medical therapy in this case series, netarsudil safely and significantly reduced IOP in patients with glaucoma, even in those using ≥ 3 glaucoma medications. Increases in IOP of ≥ 3 mmHg occurred in a small number of patients. Subjective vision changes and conjunctival hyperemia were the most frequently reported side effects.

Rho kinase (ROCK) inhibitors in the management of corneal endothelial disease

PURPOSE OF REVIEW

Rho kinase (ROCK) inhibitors are growing increasingly relevant in ophthalmology, and the goal of this review is to summarize their mechanisms of action and potential applications in the subspecialties of glaucoma, retina, and cornea. We will focus specifically on corneal endothelial wound healing, for which ROCK inhibition demonstrates particular promise.

RECENT FINDINGS

ROCK inhibition has been shown to promote corneal endothelial cell proliferation, increase intercellular adhesion, and suppress apoptosis. Topical ROCK inhibitor treatment has exhibited potential use in Fuchs endothelial dystrophy, corneal edema from acute surgical trauma and other etiologies, and tissue engineering therapy for the endothelial disease. Ripasudil and netarsudil, the two ROCK inhibitors available for ophthalmic use, are generally very well tolerated with mild and transient local side effects.

SUMMARY

ROCK inhibitors are revolutionizing the subspecialty of cornea, and further research is needed to compare long-term outcomes of ROCK inhibitor therapy to those of conventional endothelial keratoplasty, including visual acuity and endothelial cell density. Other possible avenues include the use of ROCK inhibitors to prolong corneal graft survival, and early data appears promising.