Valproic acid could delay a form of progressive blindness caused by the degeneration of the retina, says a study conducted by researchers at the University of Massachusetts Medical School (UMMS).

The disease, known medically as retinitis pigmentosa (RP), results in the retina starting to degenerate resulting in a progressive reduction in side vision followed by night vision before the patient eventually ends up completely blind.

UMMS researchers have probably landed on a treatment for this neurodegenerative disease of the retina. They found that valproic acid could be beneficial for patients suffering from this disease that probably results from the death of light sensitive cells in the eye.

“Inflammation and cell death are key components of retinitis pigmentosa. It appears the valproic acid protects photoreceptor cells from this,'' says Dr. Shalesh Kaushal, MD, PhD, Chair of ophthalmology and associate professor of ophthalmology and cell biology at UMMS.

Dr. Kaushal believes that if the results of their observations could be further substantiated by randomized clinical trials then low dose valproic acid could have tremendous potential to help the thousands of people suffering from this eye disease.

The researchers have analysed the data from a three-year clinical trial undertaken to ascertain the capacity of valproic acid as a treatment for RP. In addition to this, they have also treated patients’ off-label with doses of valproic acid ranging from 500mg to 750mg daily over a two to six month period to observe the impact.

The treatment for RP is not always easy because more than 40 different genes are involved in the development and progression of the eye disease. Several potential therapies for RP including nutritional supplementation, vitamin A supplementation, light reduction or gene therapy are being investigated, currently.

Valproic acid, which has been approved for treating seizures, migraines and bipolar disorder, has also been found effective in blocking the inflammatory response pathway and cell death. This is precisely the quality that compelled UMMS researchers to rope in valproic acid to treat the retinal disease as well.

Traditionally, moving a new scientific discovery from the bench to the patient requires a significant investment of time and resources. Repurposing drugs already approved by the FDA that have been shown as safe, such as valproic acid, is an economical and time-efficient way to quickly bring new treatments to patients, says Dr. Kaushal in the study published in the British Journal of Ophthalmology.