The goal of this clinical trial is to learn if orally administered nicotinamide riboside works to slow the progression of early Alzheimer disease in adults. It will also learn about the safety of drug nicotinamide riboside. The main questions it aims to answer are:
* Does drug nicotinamide riboside slow the progression of Alzheimer disease as measured by the Clinical Dementia Rating scale. * What medical problems do participants have when taking drug nicotinamide riboside? Researchers will compare drug nicotinamide riboside to a placebo (a look-alike substance that contains no drug) to see if nicotinamide riboside works to treat early Alzheimer disease.
Participants will:
* Take drug nicotinamide ribosie or a placebo every day for 24 months * Visit the clinic once every 26 weeks for checkups and tests
Diagnosis Early clinical AD, e.g. Stage 3 MCI or Stage 4 (mild AD dementia), as defined by the FDA, 2024.
Biomarker evidence consistent with AD neuropathologic change, defined by CSF markers, i.e. Aβ42 < 1030 ng/L and P-tau181/Aβ42 > 0,023 ng/L and/or T-tau/Aβ42 > 0,28 ng/L* or AD amyloid biomarker (as determined either by visual reading of amyloid PET scans using an approved ligand
Diagnosed with AD within 2 years from baseline.
Capacity to provide written informed consent for study participation defined as Montreal Cognitive Assessment (MoCA) score ≥ 16 or Mini Mental State Evaluation (MMSE) score ≥ 20. MMSE or MoCA must have been performed within 6 months prior to baseline. If there is any doubt regarding the participants capacity to give informed consent, this will be determined by an evaluation by a consultant clinician who is not associated with the N-AD study.
Diagnosis of dementia other than probable AD.
Abundant vascular pathology, i.e. Fazekas >2. or >3 lacunar infarcts, stroke involving a major vascular territory, severe small vessel, or white matter disease
More than 1 core feature of dementia with Lewy bodies, i.e; recurrent visual hallucination, cognitive fluctuations, REM sleep behaviour disorder, one or more spontaneous cardinal features of parkinsonism (tremor, rigidity and bradykinesia).
Comorbidity that precludes study participation or data interpretation.