Can a group of HIV drugs prevent Alzheimer's?

A class of drugs used against HIV, called NRTIs, could also prevent Alzheimer's disease. The evidence is so compelling that clinical trials have already been requested to test whether these drugs have any effect on this devastating disease.

A team from the University of Virginia (USA) discovered that people who take these drugs are substantially less likely to develop Alzheimer's. Their results are published in the journal Alzheimer's & Dementia .

This same team, led by Jayakrishna Ambati , had already identified a possible mechanism by which drugs could prevent Alzheimer's.

This finding prompted an analysis of two of the nation's largest health insurance databases to assess the risk of Alzheimer's among patients prescribed these drugs. In one, the risk of developing Alzheimer's decreased by 6% each year patients took the drugs . In the other, the annual decrease was 13%.

Considering that more than 10 million people worldwide develop Alzheimer's each year, Ambati reasons, "our results suggest that taking these drugs could prevent approximately 1 million new cases of Alzheimer's each year."

NRTIs, or nucleoside reverse transcriptase inhibitors, are used to prevent the HIV virus from replicating in the body.

This isn't the first time these drugs have been linked to Alzheimer's. A study published in Nature previously showed that lamivudine, a drug from the reverse transcriptase inhibitor family, was able to reduce age-related inflammation and other signs of aging in mice, including traits associated with Alzheimer's.

Furthermore, Ambati and his team previously determined that these drugs can also prevent the activation of inflammasomes , important players in our immune system. These proteins have been linked to the development of Alzheimer's disease, so this team wanted to see if patients taking these inflammasome-blocking drugs were less likely to develop Alzheimer's.

To do so, they reviewed 24 years of data on more than 270,000 patients, at least 50 years old, who were being treated with medications for HIV or hepatitis B, another disease treated with NRTIs. They excluded patients with a previous diagnosis of Alzheimer's.

Even after adjusting for factors that could distort the results, such as the presence of preexisting medical conditions, the researchers determined that the reduction in Alzheimer's risk among patients taking NRTIs was significant and substantial.

The researchers note that patients taking other types of HIV medications did not show the same reduction in Alzheimer's risk as those taking NRTIs. Therefore, they assert that NRTIs warrant clinical trials to determine their ability to prevent Alzheimer's.