Retinal diseases are the leading cause of blindness in the western world

Diabetes affects over 500 million people globally—a number expected to double by 2040. Approximately one-third of these individuals will develop diabetic retinopathy, a condition characterized by vascular leakage and abnormal blood vessel growth in the retina. Of those affected, nearly 50% will go on to develop diabetic macular oedema (DMO) and/or proliferative diabetic retinopathy (PDR). With diabetic eye disease impacting around 30% of all people with diabetes, there is a clear and urgent need for an effective, non-invasive treatment.

Non-proliferative diabetic retinopathy (NPDR) is the early stage of diabetic eye disease, in which chronically elevated blood glucose damages retinal blood vessels—leading to microaneurysms, haemorrhages, and fluid leakage without new vessel growth. If left untreated, NPDR can progress to proliferative diabetic retinopathy (PDR), NPDR is often asymptomatic in its early stages, underscoring the importance of routine retinal screening. Major risk factors include long-standing diabetes, poor glycaemic control, hypertension, and hyperlipidaemia.

Proliferative diabetic retinopathy (PDR) is the advanced stage of diabetic eye disease, characterised by abnormal neovascularization triggered by chronic hyperglycaemia. These fragile new blood vessels form on the retina or optic disc and can lead to severe vision loss through vitreous haemorrhage, tractional retinal detachment, or both.

Diabetic macular oedema (DMO) frequently coexists with proliferative diabetic retinopathy (PDR) and is characterized by the accumulation of fluid in the macula, the part of the retina responsible for sharp central vision. This leads to visual impairment, with symptoms such as blurred vision or floaters. However, early stages are often asymptomatic, necessitating regular ophthalmologic screening for individuals with diabetes.

Current treatments for neovascular eye diseases, including diabetic macular oedema (DMO) and proliferative diabetic retinopathy (PDR), rely on broad-spectrum VEGF inhibitors delivered via intraocular injection. While anti-VEGF therapy is a well-established standard of care, these agents target all isoforms of VEGF indiscriminately. This non-specific inhibition can result in limited efficacy, resistance, systemic and ocular toxicity, and off-target effects.

Despite their widespread use, these treatments restore vision in fewer than 40% of patients and require monthly injections directly into the eye, which are costly and associated with significant risks such as ocular hypertension, endophthalmitis, and retinal detachment. This invasive delivery method is particularly unsuitable for patients with non-proliferative diabetic retinopathy (NPDR), who typically show no vision loss and are therefore unlikely to undergo injection-based therapy.

Exonate’s approach is differentiated by:                                               

Novel Mechanism of Action: EXN407 uniquely targets SRPK1, offering a new way to modulate VEGF-driven disease progression. This represents a differentiated approach in a space where VEGF has already been validated as a key driver.
Patient-Preferred Delivery: Eye drops are the optimal treatment modality for early-stage diabetic eye disease such as NPDR. Patients and physicians are understandably reluctant to use invasive injections to treat a symptom-free condition.
Favourable Safety Profile: Unlike oral therapies, which carry a higher risk of systemic side effects, our topical formulation minimizes systemic exposure, offering a safer and more targeted treatment option. (Read more about how they work here.)