The ever increasing socio-economic burden of vision loss is a growing public health concern, both globally and in India. Vision loss is the third-largest global impairment after anemia and hearing loss. While there exists general public awareness about certain kinds of visual impairments like cataract, glaucoma and refractive errors, visual disabilities arising out of retinal disorders is on a constant rise Globally, retinal diseases account for approximately 6% of blindness. Certain retinal disorders which are a consequence of uncontrolled blood sugar levels (DR and DME) and aging (nAMD), can be sight threatening, leading to permanent and irreversible vision loss, if not diagnosed and treated in a timely manner.
While initiatives in India like the National Program for Control of Blindness & Visual Impairment (NPCBVI) have made commendable strides in the reduction of cataract and glaucoma related blindness (anterior or front part of the eye), there is an urgent need to also drive focus on retinal health (posterior or back part of the eye); as damage to retina nerve cells is irreversible and can cause loss of central vision which is more debilitating, causing more risk of injury and poor quality of life. In India, there’s been an alarming increase in the past decade in the share of retinal disorders causing blindness. These numbers will continue to rise as our population grows, ages and the number of people living with diabetes and hypertension continues to increase.
Ecosystem challenges & barriers in diagnosis
Despite the magnitude of the growing concern around retinal health in India, there exists ecosystem barriers, policy gaps, awareness challenges and treatment adherence lapses:
- Capacity constraints and an acute shortage of trained retina specialists: In India, the Ophthalmologist pool is highly skewed towards the anterior segment, accounting for almost 80% with only about 5% to 8% specializing in retina, that too concentrated in Tier 1 cities.
- Lack of standardized treatment guidelines: In India, there exists a practice of regional variance in treatment protocols which severely impacts patient outcomes. A standard practice is ‘step therapy’ in which newer treatment options are reserved for recalcitrant patients, wherein the vision has already deteriorated to the extent that these innovative therapies demonstrate little or no result in restoring vision.
- Poorly integrated health systems for diagnosis and patient referrals: Especially for diabetic patients, the referral pathways are fractured. Patients present themselves to retina specialists when these disorders have already reached advanced stages.
- Treatment burden of available therapies: Existing treatments are burdensome, requiring frequent eye injections. This may lead to under-treatment, arising out of adherence gaps; which leads to further retinal damage.
- Lack of public awareness: As a prevailing practice in our country, eye health is neglected. Families, corporates and institutions do not include retina in the annual health check up packages. General public is grossly unaware that conditions like diabetes can even affect vision.
Challenges in the current treatment landscape & need for innovative therapies
From a patient perspective, they fear being injected in the eye as part of their treatment. Add to that the challenge of getting frequent injections and the hardship of multiple visits to eye care facilities, while dealing with poor vision. This is what many face due to older treatment options like anti-VEGFs even though they are commonly used. Previously approved treatments have only partially addressed the processes – or ‘pathways’ – that drive the development and progression of nAMD and DME. There has been a need for innovation beyond standard IVT treatment.
While IVT injections (eye injections) have brought a promising new set of options for patients, there are still unmet needs in the treatment of DME & nAMD. Current treatment requires frequent injections that burden a patient with recurring cost, inconvenience of travel and the need to depend on a caregiver. Newer emerging treatments focus on providing better outcomes with less burden on patients in terms of number and frequency of injections.
Need to adopt advanced treatment options
In order to have perfect vision, the vessels in our retina need to be stable and strong. However, the vessels of people living with retinal conditions are unstable, leaky, inflamed and grow abnormally. VEGF is one key pathway involved in the development and progression of retinal conditions. Blocking the VEGF pathway successfully stops vessels in the retina leaking blood and fluid, and new unhealthy vessels from growing. However, VEGF is not the only pathway involved. Ang-2 contributes to vascular instability, causes inflammation and facilitates and amplifies the actions of VEGF on vessels, potentially leading to a more severe condition in the long-term. Treatment options that target VEGF alone therefore only partially address the biology of the disease. We know that retinal conditions like DME and nAMD can lead to permanent and irreversible sight damage; and that the first chance of treatment is the best chance of treatment. So the goal is to treat patients with newer innovative therapies in first line settings, rather than reserving such therapies for patients whose sight condition has worsened over time.
Advanced treatment options, that block both pathways involving Ang-2 and VEGF-A, are designed to stabilize blood vessels, thereby reducing inflammation, leakage and abnormal vessel growth, will go a long way in providing sustained disease control and maintaining vision outcomes.
Quote from HCP – Visual impairment is a growing public health concern, both globally and in India. What’s significant to note is that more than 90% of blindness is treatable or preventable and it still affects more than 1 billion people globally. While general public awareness exists about vision disorders such as cataract, glaucoma and refractive errors, a silent epidemic of retinal vision loss is gaining momentum. Retinal diseases, including age-related macular degeneration, diabetic retinopathy and diabetic macular edema are the most common causes of irreversible blindness and urgent action is needed to arrest their rising occurrence. – Dr. Bhuvan Chanana, Senior VR Consultant and Surgeon, Bharti Eye Institute, New Delhi.
Quote from HCP – Quality of life is severely compromised in people with major blinding retinal diseases such as nAMD and DR. At a population level, vision health is critical to broader health. Loss of sight can have wide-ranging impacts on a person’s life, including on their cognitive development, motor skills, physical activities, socialization and overall wellbeing. Sight loss is not only a health issue, but also an economic issue. It is therefore more critical than ever to ensure that there are adequate levels of investment, in the form of resources allocated into services, infrastructure and effective eye interventions to address the unmet need associated with vision impairment. Of all types of eye conditions, retinal disorders are more complex to treat because how they develop and progress varies greatly. Additionally, treating retinal conditions becomes even more challenging given the paucity of infrastructure and medical personnel in India, as there are only 13 ophthalmologists per million population. Given this dire constraint, newer innovative and longer lasting therapies that can reduce the treatment burden can be a game changer in preserving sight and in optimizing our healthcare system’s capacity. – Dr. Nikhil Pal, Principal Vitreoretinal Consultant – Max Healthcare, New Delhi.