The treatment of presbyopia and emerging presbyopes without cataracts hasn’t changed much since Ben Franklin invented bifocals. Obviously, we can do better than that, as correcting presbyopia during cataract surgery has been one of the greatest areas of advancement over the last 15 years.
Attempts at corneal inlays to correct presbyopia haven’t produced the outcomes we’d hoped for. From there, however, we did learn that aperture optics can help with close-up vision by increasing depth of focus. This knowledge has led to the development of innovative pharmacologic solutions, including a presbyopia-correcting eye drop by Orasis (OR-uh-sis) Pharmaceuticals, which is now in phase 3 clinical trials.
Surgical Options but With Tradeoffs
Our recommendations for presbyopia correction are tempered by considerations of a patient’s age and our assessment of risks versus benefits. Typically, we don’t perform lens-based surgeries on emerging presbyopes unless they have additional refractive error, such as high hyperopia or moderate to high myopia. Instead, we advise patients to use readers or bifocals, or we prescribe monovision or bifocal contact lenses. For some, we may consider monovision LASIK. While these are the most frequently discussed options for presbyopes in their 40s to mid-50s, there are some meaningful trade-offs with all of them.
Patients who use optical devices—eyeglasses and contact lenses—have to put them on, take them off, and care for them, and they can be broken or lost. Patients with monovision LASIK give up some distance vision in one eye in exchange for near vision in that eye, and both eyes aren’t working together at all distances.
CURRENT STATUS OF ORASIS CSF-1
The Orasis (OR-uh-sis) presbyopia-correcting eye drop induces miosis to create a pinhole effect and increase depth of focus for improved near vision. The company reports clinical trial results to date have demonstrated significant improvements in near vision and a superior safety profile. The drop is currently in NEAR-1 and NEAR-2 phase 3 trials in the United States.
The lenses that are available for refractive lens exchange, which some people might consider, are not as good as our natural lenses were when we were 20 years old. There’s a chance for positive dysphotopsias, patients don’t get a smooth range of vision, and people in their 40s to 50s still have accommodative capabilities.
An eye drop that increases depth of focus, can be used on an as-needed basis, and takes advantage of the accommodation we still have in our 40s and 50s can be a great solution for many people.
Look First to Your Plano Presbyopes
Within the emerging presbyope category are two subcategories: people who have refractive error and are moving to bifocals; and people who don’t wear eyeglasses or contact lenses but are starting to need some help with their near vision. I think this eye drop becomes almost a no-brainer—and I don’t use that term lightly—for the latter group.
In my opinion, presbyopia-correcting eye drops likely will be the treatment of choice for plano presbyopes who have never had to use an optical device. Their reasoning? “Why not just carry eye drops in my pocket and add a drop when I need to see up close?”
Don’t discount patients who are already wearing eyeglasses or contact lenses and are now becoming presbyopic. Some may look at this as an opportunity to finally be free of their devices, thinking, “I can get LASIK for distance and then just put drops in my eyes as needed for my up-close vision.” I also believe pseudophakes who have monofocal lenses will be able to benefit from these drops.
To me, however, presbyopia-correcting eye drops should definitely be our first choice for plano presbyopes.
Balancing Efficacy, Safety, and Comfort
Safety and efficacy are paramount for any pharmaceutical agent, and eye drops must be easy to use and comfortable. Side effects such as stinging and burning on instillation must be minimal and short-lived, and preservative-free drops are preferred to avoid a negative impact on the ocular surface. Presbyopia-correcting eye drops must meet additional criteria.
From my point of view, first, we need to remember that we do have options for presbyopia that are essentially risk-free—bifocals, for example. Therefore, a presbyopia-correcting eye drop has to be close to risk-free. Second, it must be comfortable, and third, it must be tolerable. In other words, it shouldn’t make my eyes red or cause any other unwanted side effects. Does it last too long or not long enough? Those are the things that I care about the most.
With the appropriate balance of efficacy, safety, and comfort, I believe we can tilt the risk-benefit ratio in favor of the Orasis product so that patients want to use it. My impression from the publicly available data is that the Orasis drop is quite comfortable. I would have no reservations at all about putting it in my own eye. I think Orasis is going to have a compelling comfort and duration story.
