Levodopa may improve vision in patients with advanced forms of age-related macular degeneration (AMD), according to a new study published in the American Journal of Medicine.

More than 15% of the age 70 and over population of the United States is living with AMD, a common cause of blindness in developed nations. Neovascular AMD (nAMD) is the abnormal growth of new blood vessels triggered by vascular endothelial growth factor (VEGF). 

This can cause fluid and blood to leak in the subretinal space of the eye. Although nAMD only accounts for 10%-15% of AMD cases, it’s responsible for 90% of the vision loss attributed to the disease, according to the study. Currently, the standard treatment is frequent anti-VEGF injections, which are effective but expensive and painful. 

The study was composed of 2 parts. In the first part, 20 patients who were newly diagnosed with nAMD who never received VEGF treatment injections were given a small dose of levodopa for a month. Each week, the participants underwent evaluations by their referring retina specialist to determine whether anti-VEGF treatment was needed. 

In the second part of the study, patients from part 1 as well as 14 new participants who received anti-VEGF treatment for at least 3 months before the study received escalating doses of levodopa. This was used to test the tolerance and efficacy of the drug. Participants were evaluated monthly by their referring retina specialist. 

In addition to being found safe and well-tolerated, levodopa delayed anti-VEGF injection therapy while improving visual outcomes, according to the study. Retinal fluid decreased by 29% in the first month. 

At the 6-month mark, the decrease was maintained and visual acuity improved to the point patients in both groups were able to read an additional line on the eye chart. This is an improvement equivalent to a change from 20/40 to 20/32. 

Eleven of the 14 patients did require anti-VEFG injections, meaning that levodopa may be unlikely as a standalone treatment in newly diagnosed nAMD patients; however, they required fewer monthly treatments. In the second group, monthly anti-VEGF injections decreased by 52%.  

Reference:
Levodopa may improve vision in patients with macular degeneration [News Release]. Philadelphia, PA. September 10, 2020. https://www.eurekalert.org/pub_releases/2020-09/e-lmi091020.php. Accessed September 11, 2020.