Antabuse is an old and known treatment for alcholism, but researchers see hope for the drug as a treatment for certain retinal degenerative diseases.
A new treatment that targets photoreceptor degeneration may restore sight in patients with dry macular degeneration and retinitis pigmentosa.
Researchers found that a drug used to treat alcoholism, called antabuse, blocks the pathway that is hyperactivated in degenerative retinal diseases. The researchers found that vision in mice that had been lost over a long period of time was partially restored in those mice who received treatment with the drug.
The study used the drug disulfiram marketed under the name Antabuse. The drug is currently used as part of treatment for alcohol use disorder because it produces an acute sensitivity to ethanol. It works by inhibiting the enzyme acetaldehyde dehydrogenase which causes many of the effects of a hangover to be felt immediately following alcohol consumption.
Antabuse Restores Vision in Mice
In a controlled study, the drug helped restore some vision in mice by suppressing sensory noise in the inner retina that was caused by dying photoreceptors in the outer retina. The type of sensory noise is brought on by the progression of outer retinal degeneration. This type of outer retinal degeneration is what happens in age-related macular degeneration and retinitis pigmentosa.
Sensory receptor noise corrupts sensory signals and limits the ability of photoreceptors to detect light. The term “noise” when used in the context of electrical signaling means a “disturbance” in the electric signals sent by photoreceptors that causes severe disruptions and the inability of the photoreceptors to correctly send signals to the visual cortex of the brain.
In the study carried out at the Center for Visual Science at the University of Rochester Medical Center the researchers found that disulfiram quieted that sensory noise and enabled the surviving photoreceptors in the outer retina to successfully send signals to the brain. They found that nearly blind mice treated with disulfiram were much better at detecting images on a computer screen.
Hope for Retinitis Pigmentosa
The researchers will now partner with other ophthalmologists to conduct a human clinical trial of disulfiram on patients with retinitis pigmentosa (RP).
Participants in the trial would be people with RP but who do not yet have complete, retinal degeneration. Because disulfiram is an anti-alcohol drug it has some severe side effects if alcohol is consumed while taking it, such as headache, nausea, and muscle cramps.
New drugs could be developed that don’t inhibit the acetaldehyde dehydrogenase enzyme but still suppress sensory noise. The researchers have tested other experimental drugs that also dramatically improved vision in mice with RP. But because disulfiram already has FDA clearance, clinical trials designed to test a different use for it could begin much sooner than a clinical trial using a new experimental drug.