In a promising breakthrough for vision care, researchers at the National Institutes of Health (NIH) have developed eye drops that could slow the progression of retinitis pigmentosa and other degenerative retinal diseases. The discovery, detailed in Communications Medicine, has shown positive results in animal studies, raising hopes for future human trials.

The innovative treatment is based on a small peptide fragment derived from pigment epithelium-derived factor (PEDF), a naturally occurring protein in the eye known for its protective effects on retinal cells. According to Dr. Patricia Becerra, senior author of the study and chief of the Section on Protein Structure and Function at the National Eye Institute, these eye drops are not a cure but represent a significant advancement in slowing vision loss.

“PEDF-based eye drops can slow progression of a variety of degenerative retinal diseases in animals, including retinitis pigmentosa and dry age-related macular degeneration (AMD),” said Dr. Becerra. “Given these results, we’re excited to begin trials in people.”

Degenerative retinal diseases, such as retinitis pigmentosa and AMD, are marked by high levels of cellular stress that gradually lead to photoreceptor death and vision loss. Although previous research highlighted the protective potential of the PEDF protein, its large size made it impractical for direct use as a treatment. Dr. Becerra and her team developed smaller peptide versions of PEDF that could reach the retina more effectively.

In the study, two peptides — dubbed “17-mer” and “H105A” — were formulated into eye drops. When administered to mice with retinitis pigmentosa-like conditions, the drops successfully reached the retina within an hour and showed no toxicity. Young mice treated with daily doses of the H105A peptide retained up to 75% of their photoreceptors and maintained strong retinal responses to light, compared to significant photoreceptor loss in untreated animals.

“For the first time, we show that eye drops containing these short peptides can pass into the eye and have a therapeutic effect on the retina,” said first author Alexandra Bernardo-Colón. “Animals given the H105A peptide have dramatically healthier-looking retinas, with no negative side effects.”

The study also explored whether these preserved photoreceptors could respond to gene therapy. Collaborators from the University of Modena in Italy demonstrated that, following the peptide regimen, gene therapy extended vision preservation for at least six months.

In addition, tests on human retinal tissue models conducted by researchers from the University of Colorado Anschutz showed that the peptides helped retinal cells withstand high levels of stress, offering encouraging evidence for potential human trials.

This research was funded by the NEI Intramural Research Program and received support from organizations including the Prevention of Blindness Society, Fondazione Telethon, HEAL-ITALIA Foundation, CellSight Development Fund, and Research to Prevent Blindness.

If successful in human trials, these PEDF-derived peptide eye drops could become a vital tool in preserving vision for individuals with degenerative retinal diseases, offering hope as they await more targeted gene therapies.