A Phase IIa clinical trial to evaluate the effects of anti-retroviral therapy in Alzheimer's disease (ART-AD)

Abstract

Retrotransposons constitute over 40% of the human genome. Studies in Drosophila, mice, cultured cells, and human brain show that retrotransposons are activated in tauopathies, including Alzheimer's disease, and causally drive neurodegeneration. The reverse transcriptase inhibitor 3TC (lamivudine) reduces retrotransposon activation and suppresses tau neurotoxicity among model systems. This phase 2a open-label trial (Pilot Study to Investigate the Safety and Feasibility of Anti-Retroviral Therapy for Alzheimer's Disease, NCT04552795, registered 09/10/2020) followed 12 participants with early Alzheimer's disease (MMSE > 24, CDR = 0.5) over 24 weeks to assess safety, tolerability, and feasibility of daily 300 mg 3TC treatment. The sample was well-educated (12-20 years) and culturally diverse (25% from underrepresented groups). In addition to a favorable safety profile and stable cognitive measures, notable significant changes in fluid-based biomarkers include reduction of glial fibrillary acidic protein (GFAP) (P = 0.03) in CSF, suggestive of reduced neuroinflammation, and elevation of Aβ42/40 (P = 0.009) in plasma, suggestive of reduced plaque load in the brain. These results warrant further exploration in a larger, placebo-controlled trial.

Keywords: Alzheimer's disease; Clinical trials.

Fig. 1. Quantification of biomarkers associated with neurodegeneration in CSF and plasma.

Quanterix was used to detect the indicated proteins in CSF (A–D) and plasma (E–H) of participants at baseline and after 24 weeks of 3TC treatment. CSF, N = 9; Plasma, N = 12. Normality testing was based on the POST-PRE difference for each target; P values are based on two-sided paired sample t-test (normal distribution) or Wilcoxon matched-pairs signed rank test (non-normal distribution).