This month I talked all about the retina with one of the best, John Kitchens, MD, a previous chief surgical fellow at Bascom Palmer who practices at Retina Associates of Kentucky. Here are some highlights of our talk.
Central Serous Retinopathy
Probably the biggest current breakthrough is in imaging, specifically enhanced-depth visualization using spectral domain or swept-source OCT. These technologies have helped us understand the critical role of the choroid, which is important because the pathogenesis of central serous retinopathy (CSR) is often related to a thickened choroid (i.e., pachychoroid). While there have been reports of systemic therapies for CSR such as mineralocorticoid receptor antagonists, aldosterone antagonists and even melatonin, the mainstay of treatment is observation for early occurrences and laser or PDT therapy for chronic cases or cases where rapid visual improvement is necessary (e.g., pilots).
In the Pipeline
The retinal disease drug pipeline is also exciting. First, we should have faricimab (Genentech) approved in early 2022. This is a bispecific antibody, meaning it binds two different targets: VEGF and ANG-2. The latter is felt to play a role in inflammation and vascular destabilization. Phase III studies for wet AMD and DME showed this drug could be used in a treat and extend approach with dosing extending to three months in over 70% of patients.
The port delivery system (PDS, Genentech) should also be approved in 2022. This is tremendously exciting as it is the first sustained-release drug delivery system for anti-VEGF. Patients in the trial benefited from six-month dosing and sustainability of treatment effect. Although the Phase III trials involved six-month refills, the Phase II LADDER study (more open-ended, with as-needed refills) showed the average refill time to be over a year (median 15 months).
There will be sustained efforts to identify patients with diabetic eye disease earlier, as current therapies show improvements in retinopathy and a decrease in vision-threatening complications such as PDR and DME. The NEI’s 10-year follow-on study of AREDS2 reaffirms that we can significantly slow progression of intermediate to advanced dry AMD with AREDS2 formulations like Pre-serVision and many others. Patients with a family history of AMD, low carotenoid levels or earlier stages of AMD may be best served with a carotenoid supplement such as MacuHealth or Ocuvite. MacuHealth’s new micromicellar formulation showed greater bioavailability with a six times higher serum response and 1.5x retinal response over a six-month supplementation period.2
The introduction of a head-mounted dark adaptometer (AdaptDx Pro, MacuLogix) is helping us improve our ability to accurately diagnose and manage AMD patients. This functional test can be administered anywhere there is a comfortable chair and with minimal technician time because the system’s voice guidance system is consistently administering adaptive feedback and instructions to the patient. This device allows us to make dark adaptation testing our standard of care for every at-risk patient age 50 and older.
Monitoring carotenoid levels in the serum, which have been shown to correlate with macular pigment, can be easily performed with a biophotonic hand scanner in less than 30 seconds. Now more than ever, patients understand the importance of overall health; carotenoid levels have been shown to not only affect AMD but improve health and cognitive ability in Alzheimer’s patients.1 Lastly, at-home monitoring (Notal Vision) can help optometry identify wet AMD earlier and improve patients’ prognosis.
The retina is one of the great opportunities for our profession, with exciting developments improving our ability to help patients with sight-threatening pathologies.
Dr. Karpecki is medical director for Keplr Vision and the Dry Eye Institutes of Kentucky and Indiana. He is the Chief Clinical Editor for Review of Optometry and chair of the New Technologies & Treatments conferences. A fixture in optometric clinical education, he consults for a wide array of ophthalmic clients, including ones discussed in this article. Dr. Karpecki's full list of disclosures can be found here.
1. Yuan C, Chen H, Wang Y, et al. Dietary carotenoids related to risk of incident Alzheimer dementia (AD) and brain AD neuropathology: a community-based cohort of older adults. The American Journal of Clinical Nutrition. 2021 Jan 113(1):200-08.
2. Green-Gomez M, Prado-Cabrero A, Moran R, et al. The impact of formulation on lutein, ze-axanthin, and meso-zeaxanthin bioavailability: A Randomised Double-Blind Placebo-Controlled Study. Antioxidants (Basel). 2020 Aug 18;9(8):767.