The world of glaucoma treatment is continuously evolving. As new treatment options emerge, we can begin to consider the patient’s lifestyle and quality of life when deciding with our patients which treatment options will be best for them. In this article we’ll be discussing what’s new in glaucoma management in 2021.
Since the FDA approval of the Rho-Kinase inhibitors in 2017, with Rhopressa (netarsudil), we now have a rho-kinase inhibitor/prostaglandin combination intraocular pressure (IOP) lowering eye drop, Rocklatan. This is a combination of netarsudil and latanoprost which uses a dual mechanism of action to enhance IOP outflow.
We now have information from the one year trial of netarsudil-latanoprost versus its individual components separately. The combination group (Rocklatan) achieved lower IOP at all time-points within the 12 months with 60.1% of these patients reaching an IOP < 16mmHg compared with 36.5% in the netarsudil only group and 34.5% of the latanoprost only group. One point to keep in mind is that more patients in the groups that included netarsudil (19.7% of netarsudil-latanoprost combination and 21.7% of the netarsudil only) dropped out of the study prior to 12 months due to adverse events as compared with the latanoprost group (1.7%), primarily due to conjunctival hyperemia.
Rocklatan may be a better option for your glaucoma patients already on latanoprost but needing a further reduction in IOP. However, keep in mind, they may have more side effects than with latanoprost alone. There is, of course, still the challenge of obtaining any newer medication through a patient’s insurance compared with glaucoma medications that have been on the market longer with generic options available.
While not brand new this year, it bears mentioning the relatively new Vyzulta, which is a combination of latanoprost and nitric oxide. It works in a dual mechanism to enhance outflow via relaxation of the trabecular meshwork.
Xelpros is latanoprost without BAK preservative available directly from Sun Pharma. Patients cash pay directly to the pharmaceutical company and receive a discount for purchasing three months at a time. Medications are shipped directly to the patient. Because no insurance is billed, no prior authorizations are needed.
SLT as first line treatment
Traditionally, in the United States, selective laser trabeculoplasty (SLT) is not offered to patients unless target IOP is not met or disease progression occurs despite multiple topical medications. However, the results of the LiGHT Trial indicate that performing SLT as a first line treatment option is as effective at lowering IOP as medical management at three years. What’s even better is that 74.2% of those receiving SLT as initial treatment did not require any topical medications at the three-year study endpoint.
While SLT may be used as a first line treatment in other countries, according to an interview in Review of Ophthalmology, in the United States, SLT is still not typically offered as first-line treatment across the board. It is, however, being offered sooner since results of the LiGHT Trial. While previously it may have been offered after a second or third medication when a patient still wasn’t meeting target IOP, today, SLT may be offered after a prostaglandin if target IOP is not being met in some practices.
This is a prime opportunity for optometrists practicing in states, where they can perform SLT, to consider this as a first- or second-line treatment. For those of us who cannot perform SLT, we can work closely with our co-managing ophthalmologists so our glaucoma patients can be treated with a simple procedure that can greatly enhance quality of life and reduce the need for topical medication.
MIGS + cataract extraction and quality of life
A study published at the end of 2020 showed that 79% of those who received micro-invasive glaucoma surgeries (MIGS) plus cataract surgery had an improved quality of life. This means we should be explaining MIGS as an option to our glaucoma patients in need of cataract surgery. If our patients hear this from their trusted optometrist—who has been treating their glaucoma for years—and are referred for MIGS/cataract combination surgery, they will better understand the need for it.
The Preserflo MicroShunt (Santen/Glaukos) is the anticipated minimally invasive shunt to look out for in 2021.
Sustained release delivery systems
We all know the limitations of topical glaucoma medications: poor adherence, difficulty with drop instillation and ocular surface disease. Many companies are working to eliminate these variables by providing novel administration routes.
Durysta is the first FDA approved sustained delivery bimatoprost implant approved for patients with open angle glaucoma and ocular hypertension. It is injected into the anterior chamber and settles in the inferior angle.
At present, this implant is limited as it only lasts for six to nine months and is only FDA approved as a one injection per eye. It may benefit patients needing to reduce eye drops for a period of time; for example, if deciding whether surgical intervention may be right for them.
Intracameral travoprost implant
The new iDose by Glaukos is a titanium travoprost eluting device that is surgically implanted in the anterior chamber angle. Results of Phase 3 trials have yet to be published. Of course there are many questions yet to be answered in terms of patient preference, surgical implantation, refilling the device, and insurance reimbursement.
Bimatoprost coated contact lens
Mediprint has recently completed phase 2a of the Sight-1 trial, testing a contact lens that releases bimatoprost continuously over one week. This stage of the trial, albeit limited, showed no adverse reaction to the contact lens delivery system (patients had an average age of 77.4 years old and were not prior contact lens wearers). The company will now move to testing efficacy and optimal dosage. This could be a simple and beneficial treatment for many glaucoma patients.
Image 1: Mediprint
This is a flexible ring coated with bimatoprost that fits in the fornices to provide sustained release glaucoma treatment. It is inserted in-office and lasts six months. It is not yet available on the market.
Image 2, below, shows the bimatoprost ring.
In image 3, we see the insertion of bimatoprost ring.
Drug-free, non-surgical treatment
While most other glaucoma treatments involve either medication or surgery, this drug-free, non-surgical method for lowering intraocular pressure is being studied. A group of researchers created a hyaluronic acid hydrogel that can be injected into the suprachoroidal space to facilitate uveoscleral outflow of aqueous. In their study testing this method on normotensive rabbits, they were able to lower IOP for four months. They are hoping to create a molecule that can maintain lower IOP for six months and facilitate semi-annual injections to maintain lower IOP.
While medications and surgical intervention for glaucoma focus on lowering IOP, nutraceuticals aim to address the other contributors to retinal ganglion cell loss: oxidative stress, apoptosis, inflammation and mitochondrial dysfunction.
The medical food Lumega-Z contains over 35 nutrients to support ocular health. In a study presented at ARVO, patients with advanced glaucoma despite controlled IOPs had improved pericentral function on FDT with 12 months of Lumega-Z use.
Ginkgo Biloba has been used in Chinese medicine for over 5000 years. It is reported ginkgo biloba has an effect specifically on normal-tension glaucoma through its ability to increase nitric oxide, increase blood flow to the optic nerve, anti-inflammatory and neuroprotective effects. Dosage typically recommended is 120mg/day or 40mg TID.
Astazanthin a potent antioxidant made from red algae was shown to reduce retinal apoptosis and oxidative stress. Recommended dose is 4mg/day.
Resveratrol/Grape Seed Extract: Another highly potent polyphenol found in grapes enhances neuroprotection and reduces oxidative stress.
On the Horizon
Another sustained-release drug delivery system for glaucoma treatment includes intracameral injections via the Glaukos iDose, phase 3 trials are expected to be completed in 2023. This travoprost eluting device is inserted into the trabecular meshwork.
More so than ever, we have the ability to consider our patients’ lifestyles when deciding what glaucoma treatment modality is right for them. Many of these new advancements in glaucoma care are still being investigated. In the future of eyecare, glaucoma treatment may never be the same as myriad new options become available to clinicians.