Alzheimer's disease (AD) is an age-related neurodegenerative disorder characterized by progressive decline in cognitive function and the ability to perform activities of daily living. The amyloid hypothesis of AD postulates that the accumulation of amyloid beta (Aβ) is an early and necessary event in the pathogenesis of AD. This hypothesis suggests that interventions that slow the accumulation of Aβ plaque in the brain or increase clearance of Aβ may be able to slow the progression of the AD clinical syndrome. AD occurs on a continuum from asymptomatic (preclinical) to mild cognitive impairment (MCI), and then to dementia in mild, moderate, and severe stages. Evidence from both genetic at-risk and age at-risk cohorts, such as in dominantly inherited AD (DIAD) suggests that the pathophysiological process of AD begins well more than a decade before the clinical stage now recognized as AD dementia, and that neurodegeneration is already apparent on MRI by the stage of mild cognitive impairment. Recent clinical trial data suggest that treating AD during the earlier stages could have the greatest potential benefit on the disease by slowing progression
The ability to identify individuals destined to develop Alzheimer's disease (AD) with a high degree of confidence provides a unique opportunity to assess the efficacy of therapies at asymptomatic and very early stages of dementia. Families with known disease-causing mutations are extremely rare and are geographically dispersed throughout the world.
Participants in this study will not yet have developed any clinical symptoms of AD; they will be "asymptomatic" carriers of mutations that cause DIAD and would be expected to perform normally on standard cognitive and functional testing. Further, most mutation carriers will have levels of AD-associated amyloid beta (Aβ) and non-Aβ biomarkers that are the same as non-carriers.
Amyloid beta is a protein that accumulates in the brain of people with AD. Although we do not understand exactly what causes AD, the abnormal accumulation of amyloid beta protein in the brain is thought to play an important role in the symptoms of AD. Recent research studies indicate that amyloid beta may start building up in the brain 15 years or more before the onset of memory loss.
Imaging and fluid biomarkers will be used to demonstrate that the treatment compounds have engaged their therapeutic targets. A set of cognitive measures designed to assess the very earliest and most subtle cognitive changes will be collected. The overall objectives of this study are to evaluate the biomarker effect, safety, and tolerability of investigational study drugs in participants who are known to have an AD-causing mutation.
The primary objective of Stage 1 is to determine if treatment with the study drug prevents or slows the rate of Aβ pathological disease accumulation demonstrated by Aβ PiB positron emission tomography (PET) imaging.
The primary objective of Stage 2 is to evaluate the effect of early anti-amyloid treatment on disease progression by assessing downstream non-Aβ biomarkers of AD (e.g., CSF total tau, NfL, MRI volume) compared to a control group from the DIAN Obs natural history study and the DIAN-TU-001 placebo-treated participants.
Remternetug is a monoclonal antibody. The mechanism of action of remternetug is to target and remove aggregated amyloid plaque, a key pathological hallmark of AD, via microglial-mediated clearance. Remternetug has demonstrated the ability to reduce brain amyloid plaque.
The remternetug arm is part of Master Protocol DIAN-TU-002 (NCT05552157)