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IntroductionFrontotemporal lobar degeneration (FTLD) is the most common form of dementia for those under 60 years of age. Increasing numbers of therapeutics targeting FTLD syndromes are being developed.MethodsIn March 2018, the Association for Frontotemporal Degeneration convened the Frontotemporal Degeneration Study Group meeting in Washington, DC, to discuss advances in the clinical science of FTLD.ResultsChallenges exist for conducting clinical trials in FTLD. Two of the greatest challenges are (1) the heterogeneity of FTLD syndromes leading to difficulties in efficiently measuring treatment effects and (2) the rarity of FTLD disorders leading to recruitment challenges.DiscussionNew personalized endpoints that are clinically meaningful to individuals and their families should be developed. Personalized approaches to analyzing MRI data, development of new fluid biomarkers and wearable technologies will help to improve the power to detect treatment effects in FTLD clinical trials and enable new, clinical trial designs, possibly leveraged from the experience of oncology trials. A computational visualization and analysis platform that can support novel analyses of combined clinical, genetic, imaging, biomarker data with other novel modalities will be critical to the success of these endeavors.

BackgroundProgressive supranuclear palsy (PSP) -Richardson's Syndrome and Corticobasal Syndrome (CBS) are the two classic clinical syndromes associated with underlying four repeat (4R) tau pathology. The PSP Rating Scale is a commonly used assessment in PSP clinical trials; there is an increasing interest in designing combined 4R tauopathy clinical trials involving both CBS and PSP.ObjectivesTo determine contributions of each domain of the PSP Rating Scale to overall severity and characterize the probable sequence of clinical progression of PSP as compared to CBS.MethodsMulticenter clinical trial and natural history study data were analyzed from 545 patients with PSP and 49 with CBS. Proportional odds models were applied to model normalized cross-sectional PSP Rating Scale, estimating the probability that a patient would experience impairment in each domain using the PSP Rating Scale total score as the index of overall disease severity.ResultsThe earliest symptom domain to demonstrate impairment in PSP patients was most likely to be Ocular Motor, followed jointly by Gait/Midline and Daily Activities, then Limb Motor and Mentation, and finally Bulbar. For CBS, Limb Motor manifested first and ocular showed less probability of impairment throughout the disease spectrum. An online tool to visualize predicted disease progression was developed to predict relative disability on each subscale per overall disease severity.ConclusionThe PSP Rating Scale captures disease severity in both PSP and CBS. Modelling how domains change in relation to one other at varying disease severities may facilitate detection of therapeutic effects in future clinical trials.

BACKGROUND: This study investigated the potential of phosphorylated plasma Tau217 ratio (pTau217R) and plasma amyloid beta (Aβ) 42/Aβ40 in predicting brain amyloid levels measured by positron emission tomography (PET) Centiloid (CL) for Alzheimer's disease (AD) staging and screening. METHODS: Quantification of plasma pTau217R and Aβ42/Aβ40 employed immunoprecipitation‐mass spectrometry. CL prediction models were developed on a cohort of 904 cognitively unimpaired, preclinical and early AD subjects and validated on two independent cohorts. RESULTS: Models integrating pTau217R outperformed Aβ42/Aβ40 alone, predicting amyloid levels up to 89.1 CL. High area under the receiver operating characteristic curve (AUROC) values (89.3% to 94.7%) were observed across a broad CL range (15 to 90). Utilizing pTau217R‐based models for low amyloid levels reduced PET scans by 70.5% to 78.6%. DISCUSSION: pTau217R effectively predicts brain amyloid levels, surpassing cerebrospinal fluid Aβ42/Aβ40's range. Combining it with plasma Aβ42/Aβ40 enhances sensitivity for low amyloid detection, reducing unnecessary PET scans and expanding clinical utility. CLINICALTRIALS.GOV IDENTIFIERS: NCT02956486 (MissionAD1), NCT03036280 (MissionAD2), NCT04468659 (AHEAD3‐45), NCT03887455 (ClarityAD) Highlights: Phosphorylated plasma Tau217 ratio (pTau217R) effectively predicts amyloid‐PET Centiloid (CL) across a broad spectrum.Integrating pTau217R with Aβ42/Aβ40 extends the CL prediction upper limit to 89.1 CL.Combined model predicts amyloid status with high accuracy, especially in cognitively unimpaired individuals.This model identifies subjects above or below various CL thresholds with high accuracy.pTau217R‐based models significantly reduce PET scans by up to 78.6% for screening out individuals with no/low amyloid. [ABSTRACT FROM AUTHOR]

Background: Tau positron emission tomography (PET) is increasingly used in the clinical evaluation of patients and as an outcome measure in Alzheimer's disease (AD) clinical trials. Due to differences in tracer properties, instrumentation, and methods of analysis, however, tau‐PET outcome data cannot currently be meaningfully compared or combined. Here, we tested i) the feasibility of adapting the Centiloid method—an approach originally developed to standardize amyloid PET—to harmonize tau‐PET quantification (CenTauRs); ii) the performance of a non‐linear mixed model‐based approach (Joint Propagation Model) that does not require the use of a reference tracer. Methods: Head‐to‐head tau‐PET data (Table 1) was included from two cohorts ([18F]RO948 vs [18F]flortaucipir, n = 37 [BioFINDER‐2]; [18F]flortaucipir [Avid A05] vs [18F]MK‐6240, n = 15, University of Pittsburgh) in which each participant was scanned with two tau‐PET tracers. Standardized uptake value ratio (SUVR) values were calculated using the inferior cerebellar cortex as the reference region. Anchor point data (Table 1) was derived for each tracer using the following criteria: CenTauR‐0, cognitively unimpaired (CU), amyloid PET negative (<10 Centiloids); CenTauR‐100, amyloid PET positive (>50 Centiloids), typical (temporoparietal) AD pattern on tau‐PET visual read, age<65 andMMSE>20. Regions‐of‐interest (ROIs) included a universal tau‐PET ROI—based on the intersection of tracer specific ([18F]flortaucipir, [18F]MK‐6240, [18F]PI‐2620, [18F]PM‐PBB3, [18F]GTP1 and [18F]RO948) masks that had been derived by subtracting average of amyloid‐negative CU images from the average AD image—as well as four subregions delineated within this ROI (medial temporal, meta‐temporal, temporoparietal and frontal) (Figure 1A). An overview of the adapted Centiloid‐like approach and the joint propagation model is shown in Figure 1B. Results: High R2 values were observed between tracers across all ROIs: [18F]RO948 vs [18F]flortaucipir, average 0.965 [range 0.923 (frontal) to 0.986 (universal)]; [18F]MK‐6240 vs [18F]flortaucipir, average 0.985 [range, 0.923 (medial temporal) to 0.991 (frontal)]. The Centiloid‐like and joint propagation model approaches provided near identical CenTauR values (Figure 2). Conclusions: Preliminary findings support the development of standardized scale for tau‐PET using both a Centiloid‐like or joint propagation model approach. Additional data and consideration of the advantages and disadvantages of each will be needed to recommend one approach over the other. [ABSTRACT FROM AUTHOR]

Alzheimer’s disease (AD) is the major cause of dementia that is now threatening the lives of billions of elderly people on the globe, and recent progress in the elucidation of the pathomechanism of AD is now opening venue to tackle the disease by developing and implementing “disease-modifying therapies” that directly act on the pathophysiology and slow down the progression of neurodegeneration. A recent example is the success of clinical trials of anti-amyloid b antibody drugs, whereas other therapeutic targets, e.g., inflammation and tau, are being actively investigated. In this dual perspective session, we plan to have speakers from leading pharmas in the field representing distinct investments in the AD space, which will be followed by the comment from scientific leadership of the Alzheimer’s Association who will speak on behalf of all stakeholders. Neuroscientists participating in the Society for Neuroscience may be able to gain insights into the cutting edge of the therapeutic approaches to AD and neurodegenerative disorders, and discuss future contribution of neuroscience to this field. [ABSTRACT FROM AUTHOR]

Introduction: The Alzheimer's disease (AD) continuum begins with a long asymptomatic or preclinical stage, during which amyloid beta (Aβ) is accumulating for more than a decade prior to widespread cortical tauopathy, neurodegeneration, and manifestation of clinical symptoms. The AHEAD 3‐45 Study (BAN2401‐G000‐303) is testing whether intervention with lecanemab (BAN2401), a humanized immunoglobulin 1 (IgG1) monoclonal antibody that preferentially targets soluble aggregated Aβ, initiated during this asymptomatic stage can slow biomarker changes and/or cognitive decline. The AHEAD 3‐45 Study is conducted as a Public‐Private Partnership of the Alzheimer's Clinical Trial Consortium (ACTC), funded by the National Institute on Aging, National Institutes of Health (NIH), and Eisai Inc. Methods: The AHEAD 3‐45 Study was launched on July 14, 2020, and consists of two sister trials (A3 and A45) in cognitively unimpaired (CU) individuals ages 55 to 80 with specific dosing regimens tailored to baseline brain amyloid levels on screening positron emission tomography (PET) scans: intermediate amyloid (≈20 to 40 Centiloids) for A3 and elevated amyloid (>40 Centiloids) for A45. Both trials are being conducted under a single protocol, with a shared screening process and common schedule of assessments. A3 is a Phase 2 trial with PET‐imaging end points, whereas A45 is a Phase 3 trial with a cognitive composite primary end point. The treatment period is 4 years. The study utilizes innovative approaches to enriching the sample with individuals who have elevated brain amyloid. These include recruiting from the Trial‐Ready Cohort for Preclinical and Prodromal Alzheimer's disease (TRC‐PAD), the Australian Dementia Network (ADNeT) Registry, and the Japanese Trial Ready Cohort (J‐TRC), as well as incorporation of plasma screening with the C2N mass spectrometry platform to quantitate the Aβ 42/40 ratio (Aβ 42/40), which has been shown previously to reliably identify cognitively normal participants not likely to have elevated brain amyloid levels. A blood sample collected at a brief first visit is utilized to "screen out" individuals who are less likely to have elevated brain amyloid, and to determine the participant's eligibility to proceed to PET imaging. Eligibility to randomize into the A3 Trial or A45 Trial is based on the screening PET imaging results. Result: The focus of this article is on the innovative design of the study. Discussion: The AHEAD 3‐45 Study will test whether with lecanemab (BAN2401) can slow the accumulation of tau and prevent the cognitive decline associated with AD during its preclinical stage. It is specifically targeting both the preclinical and the early preclinical (intermediate amyloid) stages of AD and is the first secondary prevention trial to employ plasma‐based biomarkers to accelerate the screening process and potentially substantially reduce the number of screening PET scans. [ABSTRACT FROM AUTHOR]