Common HIV drugs can prevent the main cause of vision loss, the study finds

Scientists have identified a group of drugs that could help stop a major cause of vision loss after they made an unexpected discovery that overturned a fundamental belief about DNA.

The drugs, known as Nucleoside Reverse Transcriptase Inhibitors, or NRTIs, are commonly used to treat HIV. The new discovery suggests that they may also be useful against dry macular degeneration, although a virus does not cause the visual conditions.

A review of four different health insurance databases suggests that people using these medications have significantly reduced their risk of developing dry macular degeneration, a condition that affects millions of Americans.

“We are very excited that the reduced risk has been reflected in all of the databases, each with millions of patients,” said Jayakrishna Ambati, MD, a researcher of the largest macular degeneration at the University of Virginia School of Medicine. “This finding offers real hope of developing the first treatment for this blinding disease.”

Target macular degeneration

The new discovery comes from Ambati; Fred H. Gage, Ph.D., of the Salk Institute for Biological Studies; and collaborators around the world. The work rewrites our understanding of DNA, and it reveals for the first time that it can be produced in the cytoplasm of our cells, outside the cell nucleus that is home to our genetic material.

The build-up of a certain type of DNA in the cytoplasm, Alu, contributes to macular degeneration, the researchers found. This accumulation appears to kill an important layer of cells that nourish the visual cells of the retina.

Based on this discovery, the researchers decided to look at drugs that block the production of this DNA to see if it can prevent vision loss. They analyzed several U.S. health insurance databases – which contained more than 100 million patients over two decades – and found that people taking NRTIs were nearly 40% less likely to develop dry macular degeneration.

The researchers call for further study to determine if these drugs or safer derivatives known as Kamuvudines, which block a major inflammatory pathway, can help prevent vision loss from dry macular degeneration.

“A clinical trial of these inflammatory inhibitors is now warranted,” said Ambati, founder of UVA’s Center for Advanced Vision. “It is also fascinating how the discovery of the complex biology of genetics and its combination with big data archeology can drive insights into new medicine.”

Ambati, from UVA’s Department of Ophthalmology, previously determined that NRTIs can also help prevent diabetes.

The researchers published their findings in the scientific journal PNAS.