Glaucoma Drops May Boost Effectiveness of anti-VEGF Injections for Macular Degeneration

MedicalResearch.com Interview with:

MedicalResearch.com Interview with: Jason Hsu, MD Retina Service, Wills Eye Hospital Assistant Professor of Ophthalmology Thomas Jefferson University Mid Atlantic Retina Medical Research: What is the background for this study? What are the main findings? Dr. Hsu: There are some patients with the wet type of age-related macular degeneration (AMD) who have persistent swelling in the retina despite regular, repeated eye injections with the anti-vascular endothelial growth factor (anti-VEGF) medications (e.g., Avastin, Lucentis, and Eylea). I had postulated that if we could decrease the turnover of fluid inside the eye, it might allow the injected medicine to stay in the eye for a longer period of time. I chose dorzolamide-timolol (brand name: Cosopt), a commonly available prescription eye drop used for glaucoma, since it is a very potent aqueous suppressant. By slowing down the production of eye fluid, I theorized it might decrease the outflow of fluid and medicine from the eye. Our study was a small, nonrandomized, exploratory pilot study. We enrolled 10 patients with wet AMD who had persistent retinal swelling despite chronic, fixed interval anti-VEGF injections. We kept patients on the exact same anti-VEGF medication and continued to see them at the exact same interval that they had been on before study enrollment. Once enrolled, the only difference is that we had them start using dorzolamide-timolol eye drops twice a day for the course of the study. The results were fairly striking with the retinal thickness decreasing from around 420 microns to 334 microns at the final visit. This decrease in swelling was significant at the first study visit after starting the drops and remained significant throughout the course of the study. Medical Research: What should clinicians and patients take away from your report? Dr. Hsu: I think it’s important to recognize that this is a short-term, uncontrolled pilot study. However, it does suggest that the addition of a commonly available glaucoma drop (dorzolamide-timolol) may boost the effect of anti-VEGF injections in patients with wet AMD who have persistent swelling. Medical Research: What recommendations do you have for future research as a result of this study? Dr. Hsu: We are about to start a larger randomized clinical trial to confirm the findings of this pilot study. In addition, we are performing a similar study in patients with swelling in the retina from diabetes and vein occlusions. Medical Research: Is there anything else you would like to add? Dr. Hsu: Anecdotally, I have been using dorzolamide-timolol in patients outside the study. In addition, some of the original study patients wished to remain on the eye drop even after the study was completed. In some of these patients, the eye drop has not only kept the swelling down in the retina, but it has allowed me to space out the time between their injections further. They seem to require less frequent injections to keep the swelling under control while using the eye drop. We hope to demonstrate this additional clinical benefit in future studies. Citation: Sridhar J, Hsu J, Shahlaee A, et al. Topical Dorzolamide-Timolol With Intravitreous Anti–Vascular Endothelial Growth Factor for Neovascular Age-Related Macular Degeneration. JAMA Ophthalmol. Published online February 25, 2016. doi:10.1001/jamaophthalmol.2016.0045.

Dr. Jason Hsu

Jason Hsu, MD
Retina Service, Wills Eye Hospital
Assistant Professor of Ophthalmology
Thomas Jefferson University
Mid Atlantic Retina

Medical Research: What is the background for this study? What are the main findings?

Dr. Hsu: There are some patients with the wet type of age-related macular degeneration (AMD) who have persistent swelling in the retina despite regular, repeated eye injections with the anti-vascular endothelial growth factor (anti-VEGF) medications (e.g., Avastin, Lucentis, and Eylea). I had postulated that if we could decrease the turnover of fluid inside the eye, it might allow the injected medicine to stay in the eye for a longer period of time. I chose dorzolamide-timolol (brand name: Cosopt), a commonly available prescription eye drop used for glaucoma, since it is a very potent aqueous suppressant. By slowing down the production of eye fluid, I theorized it might decrease the outflow of fluid and medicine from the eye.

Our study was a small, nonrandomized, exploratory pilot study. We enrolled 10 patients with wet AMD who had persistent retinal swelling despite chronic, fixed interval anti-VEGF injections. We kept patients on the exact same anti-VEGF medication and continued to see them at the exact same interval that they had been on before study enrollment. Once enrolled, the only difference is that we had them start using dorzolamide-timolol eye drops twice a day for the course of the study. The results were fairly striking with the retinal thickness decreasing from around 420 microns to 334 microns at the final visit. This decrease in swelling was significant at the first study visit after starting the drops and remained significant throughout the course of the study.

Medical Research: What should clinicians and patients take away from your report?

Dr. Hsu: I think it’s important to recognize that this is a short-term, uncontrolled pilot study. However, it does suggest that the addition of a commonly available glaucoma drop (dorzolamide-timolol) may boost the effect of anti-VEGF injections in patients with wet AMD who have persistent swelling.

Medical Research: What recommendations do you have for future research as a result of this study?

Dr. Hsu: We are about to start a larger randomized clinical trial to confirm the findings of this pilot study. In addition, we are performing a similar study in patients with swelling in the retina from diabetes and vein occlusions.

Medical Research: Is there anything else you would like to add?

Dr. Hsu: Anecdotally, I have been using dorzolamide-timolol in patients outside the study. In addition, some of the original study patients wished to remain on the eye drop even after the study was completed. In some of these patients, the eye drop has not only kept the swelling down in the retina, but it has allowed me to space out the time between their injections further. They seem to require less frequent injections to keep the swelling under control while using the eye drop. We hope to demonstrate this additional clinical benefit in future studies.

Citation:

Sridhar J, Hsu J, Shahlaee A, et al. Topical Dorzolamide-Timolol With Intravitreous Anti–Vascular Endothelial Growth Factor for Neovascular Age-Related Macular Degeneration. JAMA Ophthalmol. Published online February 25, 2016. doi:10.1001/jamaophthalmol.2016.0045.

Dr. Jason Hsu (2016). Glaucoma Drops May Boost Effectiveness of anti-VEGF Injections in Macular Degeneration 

Last Updated on February 27, 2016 by Marie Benz MD FAAD