Targeting MMP to Treat Open-Angle Glaucoma
Sahar Bedrood, MD, PhD: What role does IOP monitoring have in future pharmacotherapies?
Joseph F. Panarelli, MD: I think as we’ve talked about already, one of the concerns we have is compliance. And for our patients who are not as compliant as we would like, they probably do have more IOP fluctuations. So once again, if we can take compliance out of their hands, if we can inject the eye with the medicine that we want to use for treatment, we could actually probably improve compliance, and I think we will see less IOP fluctuations and hopefully better control of the disease.
Dr. Bedrood: Please explain the role of matrix metalloproteinases in the extracellular matrix and the ciliary body.
Dr. Panarelli: I think this is a good question. It’s important to understand truly at the cellular level what is going on in glaucoma because some of our patients are into this and they actually want to know what is going on. When we’re talking about the trabecular meshwork, the reason that outflow is impeded is there’s a build up of extracellular matrix. What is responsible for clearing away the extracellular matrix are, in fact, these matrix metalloproteinases. So, for patients with glaucoma, we really see that they have a decrease in the matrix metalloproteinases, and that’s because they have an increase in something called TIMMPs, what are called tissue inhibitors of MMPs. It’s really all about this balance of TIMMPs and MMPs. And for our patients with glaucoma, they don’t have the proper regulation, therefore they have a build-up of extracellular matrix. And what I tell patients is this proteinaceous debris, it’s this junk that gets clogged up in their trabecular meshwork, and that’s what is causing their rise in their pressure.
Dr. Bedrood: Other modalities that are on the horizon like ocular inserts, sustained release, nanoparticle technology, implants – how are those going to be used in the future of open-angle glaucoma??
Dr. Panarelli: It’s hard to say at this point which of these is going to have the brightest future. But certainly all can have a role. We’re starting to see some good results from these ocular inserts in the canaliculus. We’ve seen other sustained release therapies that have come out from Ocular Therapeutix. There’s a number of different medicines and a number of different ways we could deliver these medicines. It’s hard to say what’s going to have the greatest value down the road; it’s still a little bit too early to say. But there’s potential to deliver medicines in so many different ways.
One of the more important advances might be in better ways to deliver eye drops. We all know that when we put an eye drop into the eye, we’re delivering way more medicine than we actually need. There’s definitely some work being done on trying to better deliver the medication to the tear film, to the surface of the cornea which is where we need the medicine to be placed. Some of that technology might be more beneficial to our patients down the road.