1INTRODUCTION
As the Alzheimer’s Disease Neuroimaging Initiative (ADNI) reaches its 20-year milestone, it is helpful to reflect on the goals, accomplishments, and future directions of this study. ADNI, with its goals of improving clinical trials in the arena of Alzheimer’s disease (AD) by optimizing and validating biomarkers while freely sharing its data and biofluid samples with the worldwide scientific community, has achieved unprecedented success. ADNI has focused on AD and has not included vascular cog nitive impairment dementia, frontotemporal degeneration, Lewy body disease, or other causes of dementia. The study has standardized and validated amyloid and tau positron emission tomography (PET) imaging, magnetic resonance imaging (MRI), and cerebrospinal fluid (CSF) biomarkers for AD diagnosis.1–3 The data generated by ADNI were used to design the clinical trials by pharmaceutical companies, including Biogen (for aducanumab),4 Eisai (for lecanemab),5 Lilly (for donanemab6 and solanezumab7), Merck (for verubecestat),8 Genen tech (for crenezumab),9 and Roche (for gantenerumab).10 ADNI has been featured in multiple special issues in journals in the past,11–13 and its data have been used in > 6000 research articles to date. This intro duction summarizes the history, major accomplishments, limitations, and future directions of this groundbreaking study.
2 MAJOR ACCOMPLISHMENTS OF ADNI IN THE LAST 20 YEARS
- 1Data and sample sharing
From the outset, ADNI emphasized the importance of data sharing by making all ADNI data available to the scientific community with out any restrictions. Considering the scale of ADNI’s study, this was a novel and radical concept in the early 2000s. To facilitate this, the Informatics Core via the Laboratory of Neuro Imaging (LONI), devel oped the Image and Data Archive (IDA) to house ADNI data. This data can be accessed through the ADNI LONI website.14 The success of this initiative is discussed extensively by Arthur W. Toga et al.15 else where in this Special Issue, focusing on the Informatics Core. Further,