Parkinson’s Drug May Treat Macular Degeneration
Mentor and mentee are hard at work in a Health Sciences lab to show that L-DOPA — used to treat Parkinson’s disease — can delay or prevent the sight-destroying eye disease.
Brian S. McKay, PhD, and his mentee, 2018 UArizona graduate Anna G. Figueroa, investigate better treatments for AMD, the most common cause of blindness in those over age 55.
A better treatment for age-related macular degeneration (AMD) is in sight, thanks to the work of the University of Arizona Health Sciences researcher Brian S. McKay, PhD, and his mentee, 2018 UArizona graduate Anna G. Figueroa.
That’s exciting news for the more than 10 million people in the United States who have AMD, the most common cause of blindness in those over age 55. AMD is particularly prevalent in Arizona, where more than 1.2 million people are 65 years of age or older.
People with the degenerative disease of the eye’s retina eventually are unable to see what is directly in front of them.
“Faces are the first thing that individuals with macular degeneration will start to miss because they no longer have a central vision,” says Figueroa.
Investigating a better treatment
With limited treatment options, many patients whose AMD has progressed from “dry” to “wet” — where abnormal blood vessels grow under the retina — opt for shots in the eye, hoping to prevent further deterioration of their already severely impaired vision. The painful, and expensive, injections must be repeated every four to six weeks.
In contrast, a potential treatment for AMD is an inexpensive drug that can be taken by mouth and is used to treat Parkinson’s disease: L-DOPA.
Dr. McKay, professor of ophthalmology and vision science at the College of Medicine - Tucson, discovered that L-DOPA can prevent and delay AMD. L-DOPA is a naturally occurring molecule made in all pigmented tissues, including the retina, where it has a role in maintaining a healthy macula, the part of the eye that provides the most high-acuity, or detailed, color vision.
“AMD is the No. 1 cause of irreversible blindness on the planet, and the current cost of treatment — just those injections — is the second-most expensive thing in the Medicare budget,” Dr. McKay says. “L-DOPA bills are generic and just pennies a pill. I hope to get rid of those shots and give people a pill they can take before they go to bed.”