Eye drop treatment in development for AMD

A new eye drop treatment for retinal conditions being developed by researchers in the US could reduce the need for intravitreal eye injections.

Early stage experiments have shown the treatment, called Vasotide, to be successful in treating animal models of wet age-related macular degeneration (AMD) and retinopathy of prematurity (ROP).

Both AMD and ROP result in the growth of abnormal, leaky blood vessels in the retina. Current treatments target the VEGF receptor, which act to block the binding of a growth factor, so reducing proliferation of the blood vessels. However, current anti-VEGF treatments are injected into the eye which can cause discomfort for patients.

The team, based at Harvard University’s Beth Israel Deaconess Medical Center (BIDMC) and the University of New Mexico, in the US, tested Vasotide in both mouse and monkey models of disease.

The drug, which was administered as eye drops and as a subcutaneous injection, acts by blocking two receptors, VEGF-1 and NRP-1. Its small size means the molecule is able to overcome issues which hampered previous unsuccessful candidates for topical retina treatments.

Early results suggest that it is as effective as existing anti-VEGF treatments in treating AMD, reducing the proliferation of new blood vessels in the retina and reducing the severity of the disease. When the drug was administered either as an injection, or as eye drops, to monkeys with laser-induced AMD and mouse models of ROP and AMD, it reduced the sprouting of blood vessels and reduced inflammation.

Dr Richard L. Sidman, an investigator in the Department of Neurology at BIDMC and Bullard Professor of Neuropathology (Neuroscience), Emeritus, at Harvard Medical School, told OT that the animal models of AMD and ROP provide “a high level of confidence in the medical relevance” and the group anticipates the findings could be replicated in patients. “Of course, it will require carefully designed translational clinical trials,” he added.

AMP Pharmaceutics, which holds the licence for Vasotide, is reportedly trying to secure funding for human trials for the drug. The researchers confirmed to OT that trials will start “as soon as logistically possible.”

Professor Sidman added: “If successful, we trust that various Vasotide formulations, consisting of either eye drops or self-dissolving contact lenses, has the potential to replace repetitive intraocular injections, which are expensive, cumbersome, and unpleasant for patients.”

The findings are published in Science Translational Medicine.

Image credit: Wellcome Images (B0006227)