Could We Use Antivirals to Treat Alzheimer’s Disease?

Chronic brain infections can trigger neuroinflammation that may, in turn, trigger some cases of Alzheimer’s disease (AD) and perhaps several other dementias. Leading suspected culprit infections are herpesviruses — particularly herpes simplex viruses (HSV) and varicella-zoster virus (VZV), which are neurotropic and produce an ineradicable, lifelong infection of cells. Observational studies correlate VZV vaccine receipt with lower subsequent dementia incidence (e.g., Nat Med 2024; 30:2777). Now, investigators have conducted a placebo-controlled, randomized trial of valacyclovir, an antiviral effective against both HSV and VZV, in 120 people with antibodies to HSV1 or HSV2 and early AD or minimal cognitive impairment with AD biomarkers…