In recent days, two new possibilities for drug therapies have come to my attention. One is a drug that cures mice of their Alzheimer’s and the other is a re-purposing of a class of drugs for HIV.
In the case of the HIV drugs, doctors at the University of Virginia found that people on them reduced their risk of Alzheimer’s disease by 10% for every year of treatment. The doctors found this by researching 24 years of insurance data involving 270,000 patients.
So what’s going on with that?
The drugs are antivirals called “nucleoside reverse transcriptase inhibitors,” or NRTIs. Inflammation is central to both HIV and Alzheimer’s, and these drugs quiet inflammation in the brain.
While the NRTIs prevent the HIV virus from replicating, they also prevent the activation of inflammasomes. Inflammasomes are proteins involved in the development of Alzheimer’s. We’ve discussed the role of cytokines in inflammation before, and inflammasomes promote cytokine storms. The researchers said that they weren’t surprised that the drug would affect the development of Alzheimer’s by reducing inflammation, but they were surprised by the strength of the effect.
Of course, “more research is necessary.” In this case, the study was observational, and such studies don’t provide convincing proof of cause and effect. So the authors of the study say that randomized control trials are still needed. But these drugs have been around for a while, and their behavior is otherwise well known.
The study was published in the May 2025 issue of Alzheimer’s and Dementia, the Journal of the Alzheimer’s Association.
The drug that cures mice is a promising drug candidate called DDL-357. It improves memory in Alzheimer’s mice by increasing levels of a protective brain protein. The protein is called clusterin, or CLU. CLU helps prevent the buildup of toxic amyloid plaques and tau proteins with which we are familiar.
Researchers at UCLA found that, in mice, DDL-357 reduces levels of tau, improves mitochondrial function, and enhances cognitive performance. Cognitive performance was tested by the checking the ability of mice to memorize mazes.
The research was published in the May 2025 issue of the journal Nature, npj | Drug Discovery, “Discovery of a small molecule secreted clusterin enhancer that improves memory in Alzheimer’s disease mice.”
Since CLU is a protein, there’s a gene responsible for generating it. And at least one variation of the gene inhibits CLU’s effectiveness in controlling the Alzheimer’s amyloid plaques and tau proteins. Among the genetic risk factors for Alzheimer’s, this gene is the third most significant. DDL-357 compensates for the deficiency in the CLU generated by this gene variant.
Here’s an article that is easier reading than the research paper.
One nice thing about DDL-357 is that it can cross the blood-brain barrier relatively easily. Therefore, it can be administered orally. But, as we’ve lamented before, this is for mice. What about people? That work remains to be done. How often do we hear about something that works great with mice, but more research is necessary ... and then we don't hear about more research?