Ofatumumab MS Study Supports Early Start Over Switch

Age-related macular degeneration (AMD) is the leading cause of visual impairment in people over age 50 years. It affects the macula, the central part of the retina responsible for sharp vision. There are two forms of AMD: The exudative or “wet” form and the atrophic or “dry” form. While no cure exists for the dry form, wet AMD can be slowed down through regular injections administered directly into the patient’s eye.

“These injection treatments have been available since 2006. They have significantly reduced blindness in countries where they are widely used,” explained Thibaud Mathis, MD, PhD, an ophthalmologist at Croix-Rousse Hospital in Lyon, France. However, these injections must be administered frequently, often monthly for the first 6 months, and then typically every 2 months for life. “This is very burdensome for patients and costly for healthcare systems and leads to a high volume of doctor visits,” he added, emphasizing the need for alternative therapies.

A study from the United States showed a lower incidence of wet AMD in patients being treated for Parkinson’s disease. “However, it wasn’t clear if this reduced risk was due to Parkinson’s itself or the treatment. So, we decided to investigate further,” explained Mathis.

Drug Delays AMD

Mathis and his team analyzed data from more than 250,000 patients using the National Health Data System to explore the link between Parkinson’s disease treatment and AMD.

“We noticed that among patients with AMD, those who were being treated for Parkinson’s disease developed AMD later than those without Parkinson’s. This delayed the age of onset by about 4 years,” Mathis explained. That is, at an average of 83 years compared with 79 years in those without Parkinson’s disease.

“This kind of pharmaco-epidemiological study is relatively new in France,” said Florian Sennlaub, research director at Vision Institute in Paris, France, and coauthor of the study. “It’s a powerful research method that allows us to study very large populations, something hospital cohorts can’t provide.”

In the next phase of their research, the team conducted studies on cellular and mouse models to pinpoint the drug’s mechanism of action.

“We discovered that L-dopa, a common Parkinson’s medication, activates a specific dopamine receptor — DRD2 — on certain blood vessels near the retina,” explained Mathis. “This activation blocks the formation of new blood vessels in the eye, which causes the development of neovascular AMD.”

These results, published in the Journal of Clinical Investigation, suggest that dopaminergic drugs could offer dual benefits — preventing and treating neovascular AMD, in addition to managing Parkinson’s disease.

However, more in-depth clinical studies are needed to determine the best drug choice, its optimal dosage, efficacy, and safety profile.

“We can’t confirm if dopamine treatments could completely replace injectable treatments, but they might reduce the number of injections needed each year. This would be a huge benefit for patients,” said Mathis.

This story was translated from the Medscape French edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.