The Rho kinase (ROCK) inhibitors, a new class of topical ocular hypotensive drugs, are a recent addition to the glaucoma treatment family. Netarsudil ophthalmic solution 0.02%, was approved by the FDA in 2017, over 20 years since the introduction of Latanoprost in 1996. ROCK inhibitors reduce the intraocular pressure (IOP) in a unique way by modulating the cytoskeleton of the trabecular meshwork, reducing its resistance and increasing trabecular outflow facility.
One concern is that almost 20% of patients in the Netarsudil arm discontinued treatment due to adverse events (AEs) compared to just over 2% in the timolol group
In this article, Khouri and colleagues compared the safety and efficacy of Netarsudil versus timolol in a multi-centre, double-masked, randomized, non-inferiority study. Patients with open-angle glaucoma or ocular hypertension having unmedicated baseline IOP > 20 to < 30 mmHg were included. The primary endpoint was mean IOP at 8:00 AM, 10:00 AM, and 4:00 PM week 2, week 6, and month 3 (a total of nine time points) in patients with baseline IOP < 25 mmHg. Secondary end points were mean IOP at the same time points in patients with IOP < 27 mmHg and in the overall study population. Safety analysis covered six months. In total 708 patients were randomized to either drug. One hundred eighty-six patients were included in each arm for the primary efficacy analysis.
Non-inferiority was defined as mean IOP within 1.5mmHg for all time points and within 1.0 mmHg at the majority of time points. It was encouraging to find that Netarsudil met the criteria for non-inferiority to timolol for both the primary and secondary efficacy analysis. Most common ocular AEs in the Netarsudil group were conjunctival hyperaemia (47.9%), cornea verticillate (vortex keratopathy) (24.4%) and conjunctival haemorrhage (16%). The majority of AEs were reported as mild and there was a good systemic safety profile. One concern is that almost 20% of patients in the Netarsudil arm discontinued treatment due to adverse events (AEs) compared to just over 2% in the timolol group. The authors gave no explanation why that was the case. Based on this study Netarsudil is non-inferior to timolol in IOP lowering in patients with ocular hypertension and open angle glaucoma. The once daily dosing may make it a convenient choice for patients.