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Abstract Introduction Composite scores may be useful to summarize overall language or visuospatial functioning in studies of older adults. Methods We used item response theory to derive composite measures for language (ADNI‐Lan) and visuospatial functioning (ADNI‐VS) from the cognitive battery administered in the Alzheimer's Disease Neuroimaging Initiative (ADNI). We evaluated the scores among groups of people with normal cognition, mild cognitive impairment (MCI), and Alzheimer's disease (AD) in terms of responsiveness to change, association with imaging findings, and ability to differentiate between MCI participants who progressed to AD dementia and those who did not progress. Results ADNI‐Lan and ADNI‐VS were able to detect change over time and predict conversion from MCI to AD. They were associated with most of the pre‐specified magnetic resonance imaging measures. ADNI‐Lan had strong associations with a cerebrospinal fluid biomarker pattern. Discussion ADNI‐Lan and ADNI‐VS may be useful composites for language and visuospatial functioning in ADNI.

Deutetrabenazine (Austedo, Teva Pharmaceuticals) is a deuterated form of tetrabenazine. It is the first deuterated drug to receive US regulatory approval and is approved for treatment of chorea in Huntington’s disease and tardive dyskinesia. Two oral single dose studies comparing deutetrabenazine (25 mg) with tetrabenazine (25 mg) in healthy volunteers evaluated the impact of deuteration on pharmacokinetics of the active metabolites, alpha‐dihydrotetrabenazine (α‐HTBZ) and beta‐dihydrotetrabenazine (β‐HTBZ), metabolite profile, safety, and tolerability. In the two‐way, cross‐over study, the mean elimination half‐life of deuterated total (α + β)‐HTBZ was doubled compared with nondeuterated total (α + β)‐HTBZ, with a twofold increase in overall mean exposure (area under the concentration‐time curve from zero to infinity (AUC0–inf)) and a marginal increase in mean peak plasma concentration (Cmax). In the mass balance and metabolite profiling study, there were no novel plasma or urinary metabolites of [14C]‐deutetrabenazine relative to [14C]‐tetrabenazine. Specific deuteration in deutetrabenazine resulted in a superior pharmacokinetic profile and an increased ratio of active‐to‐inactive metabolites, attributes considered to provide significant benefits to patients.