It is not an easy task for glaucoma patients to adhere to a lifelong regimen of eye drop therapy. Between cost, remembering daily dosing, tolerating it enough not to skip doses, and successfully instilling the drops, it’s a lot to ask, particularly as patients age and often have other health issues to deal with, including memory loss.

Studies have shown that complex regimens involving more than one or two bottles cause patient adherence to drop. Worse, adding a second or third bottle containing preservatives like benzalkonium chloride increases the risk of ocular surface disease (OSD), which only leads to more non-adherence.

Compliance and Long-Term IOP Control

The importance of medication compliance and controlling IOP long-term cannot be overstated, says Wisconsin-based ophthalmologist Inder Paul Singh, M.D.

While the LiGHT study showed that patients treated with selective laser trabeculoplasty (SLT)  were less likely to need incisional glaucoma filtration surgery than those treated with medication, there are medications that can provide IOP reduction relatively equal to SLT or to minimally- invasive glaucoma surgery (MIGS). These topical medications will always be needed. But Singh says patients aren’t using these medications consistently enough to reap the full benefits.

Singh typically begins medication therapy with a brand-name glaucoma drug for the first, and sometimes second, bottle. But for three or four medications, or if cost or compliance are an issue with just two meds, he has found that fixed-combination medications such as Simple Drops® by ImprimisRx have been an effective solution. This enables him to streamline a patient’s regimen to one bottle once a day, or one bottle in the morning and one in the evening. 

IOP Fluctuation From Inconsistent Use

Often, poorly controlled IOP is due to inconsistent use of eye drops—not because the drops don’t work. 

According to the Advanced Glaucoma Study, greater than 3 mm of IOP fluctuation over the long-term can increase visual field loss. Study participants with a low average IOP saw more than a three-fold progression with IOP fluctuation. Simplifying their glaucoma therapy could increase adherence enough to avoid fluctuation, Singh says.

He has seen this borne out in his own research, specifically in his paper “Clinical outcomes after use of new combinations of topical antiocular hypertensive medications to maintain or lower IOP in patients with glaucoma,” which he presented at the 2018 American Society of Cataract and Refractive Surgery Annual Meeting. 

For most of his patients, moving to a 3-in-1 or 4-in-1 eye drop lowered their IOP, particularly in those who had uncontrolled IOP on three or more bottles. Four of these patients were able to avoid surgery.

Knowing Cost and Ingredients

There are other major advantages to prescribing combination drops, explains Singh:

• The practitioner has a better idea of what a combination formulation will cost the patient, versus multiple separate bottles. 
• The patient will not be given generics from the pharmacy, which can vary greatly in pH, viscosity, and other aspects of their inactive delivery ingredients that can affect the drop’s bioavailability, efficacy, safety, and tolerability. (Even dropper and bottle quality can vary significantly, which can cause spillage and lower the total number of doses.)
• Preservative-free drops can be prescribed to avoid ocular surface toxicity. Roughly half of glaucoma patients have concurrent OSD, are more likely to experience negative effects from topical therapies, and so are more prone to non-adherence and progression. Avoiding toxicity to the ocular surface is also advantageous for any future surgery.

In a perfect world, Singh says, he might prefer using multiple bottles of branded medication. But since patients aren’t consistently applying the medication, their IOPs are fluctuating and disease is progressing. “A simplified regimen of compounded fixed-combination glaucoma therapy,” he ads, is a very welcome solution to these real-world problems.”

*Singh, I.P. (2022, January 24). Simplifying glaucoma medical therapy for our patients. Ophthalmology Times. https://www.ophthalmologytimes.com/view/simplifying-glaucoma-medical-therapy-for-our-patients