Common HIV drugs may prevent major cause of vision loss, study concluded

Scientists have identified a group of drugs that can help prevent one of the main causes of vision loss after making an unexpected discovery that overturns a fundamental belief about DNA.

The drugs, known as Nucleoside Reverse Transcriptase Inhibitors, or NRTIs, are commonly used to treat HIV. The new finding suggests that they may also be useful against dry macular degeneration, although a virus does not cause this vision-stealing disease.

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

“We are extremely excited that the reduced risk has been replicated across all databases, each with millions of patients,” said Jayakrishna Ambati, MD, a macular degeneration researcher at the University of Virginia School of Medicine. “This discovery offers real hope in the development of the first treatment for this blindness disease.”

Aiming at macular degeneration

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

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

Based on this discovery, the researchers decided to examine drugs that block the production of this DNA, to see if they can help prevent vision loss. They analyzed several health insurance databases in the United States – covering more than 100 million patients over two decades – and found that people taking NRTIs were almost 40% less likely to develop dry macular degeneration.

Researchers are calling for more studies to determine whether these safer drugs or derivatives known as Kamuvudines, which block one of the main inflammatory pathways, can help prevent vision loss due to dry macular degeneration.

“A clinical trial of these inflammasome-inhibiting drugs is now warranted,” said Ambati, the founding director of UVA’s Center for Advanced Vision Science. “It is also fascinating how discovering the intricate biology of genetics and combining it with big data archeology can generate insights into new drugs.”

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

The researchers published their findings in the scientific journal PNAS.