Clinical-stage ophthalmology company Acucela has started a Phase ll clinical trial to evaluate the benefits of emixustat hydrochloride (emixustat) to treat proliferative diabetic retinopathy (PDR).
It has enrolled the first patient for the randomised, placebo-controlled trial.
The company has already submitted a clinical study protocol to the US Food and Drug Administration (FDA) and has received Institutional Review Board approval to initiate the study.
During the three-month study, 20 patients will be dosed with oral emixustat, which is a once-daily, orally administered small molecule that inhibits RPE65, an enzyme crucial to the visual cycle, the chemical pathway in the retina central to the initiation of visual perception.
The study endpoints include changes in cytokine expression levels associated with PDR severity and changes in ocular neovascularisation.
Diabetic retinopathy is a progressive condition involving damage to the retinal microvasculature occurs as a result of chronic hyperglycemia.
These vascular changes ultimately lead to a chronic decrease in oxygen supply (hypoxia) to the retina.
PDR occurs when chronic retinal hypoxia causes proliferation of new, fragile vessels that tend to leak fluid and blood.
This is the most advanced stage of diabetic eye disease and can lead to permanent vision loss.
Today, PDR affects more than 19 million people worldwide, and this number is expected to grow to almost 22 million by 2020.
Acucela said that emixustat has been shown to play a critical role in slowing the progression of multiple retinal degenerative diseases in animal models, including geographic atrophy (GA) secondary to age related macular degeneration (AMD).
Emixustat is currently being developed by Acucela in collaboration with Otsuka Pharmaceutical.
Image: PDR is the most advanced stage of diabetic eye disease and can lead to permanent vision loss. Photo: courtesy of National Eye Institute, National Institutes of Health.