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Abstract: Plasma pTau181, a marker of amyloid and tau burden, was evaluated as a prognostic predictor of clinical decline and Alzheimer's disease (AD) progression of amyloid-positive (Aß+) patients with mild cognitive impairment (MCI). The training cohort for constructing the Bayesian prediction models comprised 135 Aß+ MCI clinical trial placebo subjects. Performance was evaluated in two validation cohorts. An 18-month ≥1 increase in the Clinical Dementia Rating Sum of Boxes was the clinical decline criterion. Baseline plasma pTau181 concentration matched clinical assessments' prediction performance. Adding pTau181 to clinical assessments significantly improved the prediction of an 18-month clinical decline and the 36-month progression from Aß+ MCI to AD. The area under the receiver operating characteristic curve for the latter increased from 71.8% to 79%, and the hazard ratio for time-to-progression improved from 2.26 to 3.11 (p < 0.0001). Baseline plasma pTau181 has the potential for identifying Aß+ MCI subjects with faster clinical decline over time. Highlights: This study assessed pTau181 as a prognostic predictor of 18-month clinical decline and extended progression to Alzheimer's disease (AD) in amyloid-positive patients with mild cognitive impairment (Aß+ MCI).The research findings underscore the promise of baseline plasma pTau181 as a screening tool for identifying Aß+ MCI individuals with accelerated clinical decline within a standard 18-month clinical trial period. The predictive accuracy is notably enhanced when combined with clinical assessments.Similar positive outcomes were noted in forecasting the extended progression of Aß+ MCI subjects to AD.
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BACKGROUND: This study investigated the potential of phosphorylated plasma Tau217 ratio (pTau217R) and plasma amyloid beta (Aß) 42/Aß40 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 Aß42/Aß40 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 Aß42/Aß40 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 Aß42/Aß40's range. Combining it with plasma Aß42/Aß40 enhances sensitivity for low amyloid detection, reducing unnecessary PET scans and expanding clinical utility. HIGHLIGHTS: Phosphorylated plasma Tau217 ratio (pTau217R) effectively predicts amyloid-PET Centiloid (CL) across a broad spectrum. Integrating pTau217R with Aß42/Aß40 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.
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BACKGROUND: Alzheimer disease (AD) is a major health problem of aging, with tremendous burden on healthcare systems, patients, and families globally. Lecanemab, an FDA-approved amyloid beta (Aß)-directed antibody indicated for the treatment of early AD, binds with high affinity to soluble Aß protofibrils, which have been shown to be more toxic to neurons than monomers or insoluble fibrils. Lecanemab has been shown to be well tolerated in multiple clinical trials, although risks include an increased rate of amyloid-related imaging abnormalities (ARIA) and infusion reactions relative to placebo. METHODS: Clarity AD was an 18-month treatment (Core study), multicenter, double-blind, placebo-controlled, parallel-group study with open-label extension (OLE) in participants with early AD. Eligible participants were randomized 1:1 across 2 treatment groups (placebo and lecanemab 10 mg/kg biweekly). Safety evaluations included monitoring of vital signs, physical examinations, adverse events, clinical laboratory parameters, and 12-lead electrocardiograms. ARIA occurrence was monitored throughout the study by magnetic resonance imaging, read both locally and centrally. RESULTS: Overall, 1795 participants from Core and 1612 participants with at least one dose of lecanemab (Core + OLE) were included. Lecanemab was generally well-tolerated in Clarity AD, with no deaths related to lecanemab in the Core study. There were 9 deaths during the OLE, with 4 deemed possibly related to study treatment. Of the 24 deaths in Core + OLE, 3 were due to intracerebral hemorrhage (ICH): 1 placebo in the Core due to ICH, and 2 lecanemab in OLE with concurrent ICH (1 on tissue plasminogen activator and 1 on anticoagulant therapy). In the Core + OLE, the most common adverse events in the lecanemab group (> 10%) were infusion-related reactions (24.5%), ARIA with hemosiderin deposits (ARIA-H) microhemorrhages (16.0%), COVID-19 (14.7%), ARIA with edema (ARIA-E; 13.6%), and headache (10.3%). ARIA-E and ARIA-H were largely radiographically mild-to-moderate. ARIA-E generally occurred within 3-6 months of treatment, was more common in ApoE e4 carriers (16.8%) and most common in ApoE ε4 homozygous participants (34.5%). CONCLUSIONS: Lecanemab was generally well-tolerated, with the most common adverse events being infusion-related reactions, ARIA-H, ARIA-E. Clinicians, participants, and caregivers should understand the incidence, monitoring, and management of these events for optimal patient care. TRIAL REGISTRATION: ClinicalTrials.gov numbers: Clarity AD NCT03887455).
Subject(s)
Alzheimer Disease , Humans , Alzheimer Disease/drug therapy , Male , Double-Blind Method , Female , Aged , Aged, 80 and over , Antibodies, Monoclonal, Humanized/therapeutic use , Antibodies, Monoclonal, Humanized/adverse effects , Middle Aged , Amyloid beta-Peptides/metabolism , Magnetic Resonance Imaging , Treatment OutcomeABSTRACT
INTRODUCTION: In trials of amyloid-lowering drugs for Alzheimer's disease (AD), differential eligibility may contribute to under-inclusion of racial and ethnic underrepresented groups. We examined plasma amyloid beta 42/40 and positron emission tomography (PET) amyloid eligibility for the ongoing AHEAD Study preclinical AD program (NCT04468659). METHODS: Univariate logistic regression models were used to examine group differences in plasma and PET amyloid screening eligibility. RESULTS: Of 4905 participants screened at time of analysis, 1724 were plasma eligible to continue in screening: 13.3% Hispanic Black, 24.7% Hispanic White, 20.8% non-Hispanic (NH) Asian, 24.7% NH Black, and 38.9% NH White. Plasma eligibility differed across groups in models controlling for covariates (odds ratio from 1.9 to 4.0 compared to the NH White reference group, P < 0.001). Among plasma eligible participants, PET eligibility did not differ by group. DISCUSSION: These results suggest that prevalence of brain amyloid pathology differed, but that eligibility based on plasma was equally effective across racial and ethnic group members. HIGHLIGHTS: Plasma amyloid eligibility is lower in underrepresented racial and ethnic groups. In plasma eligible adults, positron emission tomography eligibility rates are similar across race and ethnicity. Plasma biomarker tests may be similarly effective across racial and ethnic groups.
Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Biomarkers , Positron-Emission Tomography , Aged , Female , Humans , Male , Alzheimer Disease/blood , Alzheimer Disease/ethnology , Alzheimer Disease/diagnostic imaging , Amyloid beta-Peptides/blood , Biomarkers/blood , Brain/diagnostic imaging , Brain/pathology , Ethnicity , Racial GroupsABSTRACT
OBJECTIVE: Many factors contribute to inadequate diversity in Alzheimer disease (AD) clinical trials. We evaluated eligibility rates among racial and ethnic groups at US sites in large global multisite trials in early AD. METHODS: Using screening data from 4 randomized, double-blind, placebo-controlled clinical trials in early AD, we assessed rates of eligibility among racial and ethnic groups controlling for other demographic covariates. Each trial incorporated positron emission tomography and/or cerebrospinal fluid to evaluate brain amyloid pathology, as well as typical eligibility criteria used in early AD trials. RESULTS: Across the trials, 10,804 US participants were screened: 193 (2%) were of Hispanic ethnicity and Black race, 2,624 (25%) were of Hispanic ethnicity and White race, 118 (1%) were of non-Hispanic ethnicity (NH) and Asian race, 696 (7%) were of NH ethnicity and Black race, and 7,017 (65%) were of NH ethnicity and White race. Data from 156 participants who did not fit into these categories were excluded. Accounting for age, sex, and trial and using NH White participants as a reference group, we observed higher probabilities of ineligibility for amyloid biomarker criteria among Hispanic Black (odds ratio [OR] = 3.20, 95% confidence interval [CI] = 2.11-4.88), Hispanic White (OR = 4.15, 95% CI = 3.58-4.83), NH Asian (OR = 2.35, 95% CI = 1.23-4.55), and NH Black (OR = 3.75, 95% CI = 2.80-5.06) participants. INTERPRETATION: Differential eligibility may contribute to underrepresentation of some minoritized racial and ethnic groups in early AD trials. Amyloid biomarker eligibility is a requirement to confirm the diagnosis of AD and for treatment with amyloid-lowering drugs and differed among racial and ethnic groups. ANN NEUROL 2024;95:288-298.
Subject(s)
Alzheimer Disease , Antibodies, Monoclonal, Humanized , Humans , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/drug therapy , Randomized Controlled Trials as Topic , Ethnicity , BiomarkersABSTRACT
BACKGROUND: Models for forecasting individual clinical progression trajectories in early Alzheimer's disease (AD) are needed for optimizing clinical studies and patient monitoring. METHODS: Prediction models were constructed using a clinical trial training cohort (TC; n = 934) via a gradient boosting algorithm and then evaluated in two validation cohorts (VC 1, n = 235; VC 2, n = 421). Model inputs included baseline clinical features (cognitive function assessments, APOE ε4 status, and demographics) and brain magnetic resonance imaging (MRI) measures. RESULTS: The model using clinical features achieved R2 of 0.21 and 0.31 for predicting 2-year cognitive decline in VC 1 and VC 2, respectively. Adding MRI features improved the R2 to 0.29 in VC 1, which employed the same preprocessing pipeline as the TC. Utilizing these model-based predictions for clinical trial enrichment reduced the required sample size by 20% to 49%. DISCUSSION: Our validated prediction models enable baseline prediction of clinical progression trajectories in early AD, benefiting clinical trial enrichment and various applications.
Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Humans , Alzheimer Disease/pathology , Magnetic Resonance Imaging/methods , Cognitive Dysfunction/pathology , Brain/pathology , Disease ProgressionABSTRACT
The efficient and accurate execution of clinical trials testing novel treatments for Alzheimer's disease (AD) is a critical component of the field's collective efforts to develop effective disease-modifying treatments for AD. The lengthy and heterogeneous nature of clinical progression in AD contributes to the challenges inherent in demonstrating a clinically meaningful benefit of any potential new AD therapy. The failure of many large and expensive clinical trials to date has prompted a focus on optimizing all aspects of decision making, to not only expedite the development of new treatments, but also maximize the value of the information that each clinical trial yields, so that all future clinical trials (including those that are negative) will contribute toward advancing the field. To address this important topic the Alzheimer's Association Research Roundtable convened December 1-2, 2020. The goals focused around identifying new directions and actionable steps to enhance clinical trial decision making in planned future studies.
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Importance: Bayesian clinical trial designs are increasingly common; given their promotion by the US Food and Drug Administration, the future use of the bayesian approach will only continue to increase. Innovations possible when using the bayesian approach improve the efficiency of drug development and the accuracy of clinical trials, especially in the context of substantial data missingness. Objective: To explain the foundations, interpretations, and scientific justification of the bayesian approach in the setting of lecanemab trial 201, a bayesian-designed phase 2 dose-finding trial; to demonstrate the efficiency of using a bayesian design; and to show how it accommodates innovations in the prospective design and also treatment-dependent types of missing data. Design, Setting, and Participants: This study was a bayesian analysis of a clinical trial comparing the efficacy of 5 lecanemab 201 dosages for treatment of early Alzheimer disease. The goal of the lecanemab 201 trial was to identify the effective dose 90 (ED90), the dose achieving at least 90% of the maximum effectiveness of doses considered in the trial. This study assessed the bayesian adaptive randomization used, in which patients were preferentially assigned to doses that would give more information about the ED90 and its efficacy. Interventions: Patients in the lecanemab 201 trial were adaptively randomized to 1 of 5 dose regimens or placebo. Main Outcomes and Measures: The primary end point of lecanemab 201 was the Alzheimer Disease Composite Clinical Score (ADCOMS) at 12 months with continued treatment and follow-up out to 18 months. Results: A total 854 patients were included in trial treatment: 238 were in the placebo group (median age, 72 years [range, 50-89 years]; 137 female [58%]) and 587 were assigned to a lecanemab 201 treatment group (median age, 72 years [range, 50-90 years]; 272 female [46%]). The bayesian approach improved the efficiency of a clinical trial by prospectively adapting to the trial's interim results. By the trial's end more patients had been assigned to the better-performing doses: 253 (30%) and 161 (19%) patients to 10 mg/kg monthly and 10 mg/kg biweekly vs 51 (6%), 52 (6%), and 92 (11%) patients to 5 mg/kg monthly, 2.5 mg/kg biweekly, and 5 mg/kg biweekly, respectively. The trial identified 10 mg/kg biweekly as the ED90. The change in ADCOMS of the ED90 vs placebo was -0.037 at 12 months and -0.047 at 18 months. The bayesian posterior probability that the ED90 was superior to placebo was 97.5% at 12 months and 97.7% at 18 months. The respective probabilities of super-superiority were 63.8% and 76.0%. The primary analysis of the randomized bayesian lecanemab 201 trial found in the context of missing data that the most effective dose of lecanemab nearly doubles its estimated efficacy at 18 months of follow-up in comparison with restricting analysis to patients who completed the full 18 months of the trial. Conclusions and Relevance: Innovations associated with the bayesian approach can improve the efficiency of drug development and the accuracy of clinical trials, even in the context of substantial data missingness. Trial Registration: ClinicalTrials.gov Identifier: NCT01767311.
Subject(s)
Alzheimer Disease , Humans , Female , Aged , Bayes TheoremABSTRACT
INTRODUCTION: Lecanemab is a humanized immunoglobulin G1 (IgG1) monoclonal antibody that preferentially targets soluble aggregated Aß species (protofibrils) with activity at amyloid plaques. Amyloid-related imaging abnormalities (ARIA) profiles appear to differ for various anti-amyloid antibodies. Here, we present ARIA data from a large phase 2 lecanemab trial (Study 201) in early Alzheimer's disease. METHODS: Study 201 trial was double-blind, placebo-controlled (core) with an open-label extension (OLE). Observed ARIA events were summarized and modeled via Kaplan-Meier graphs. An exposure response model was developed. RESULTS: In the phase 2 core and OLE, there was a low incidence of ARIA-E (<10%), with <3% symptomatic cases. ARIA-E was generally asymptomatic, mild-to-moderate in severity, and occurred early (<3 months). ARIA-E was correlated with maximum lecanemab serum concentration and incidence was higher in apolipoprotein E4 (ApoE4) homozygous carriers. ARIA-H and ARIA-E occurred with similar frequency in core and OLE. DISCUSSION: Lecanemab can be administered without titration with modest incidence of ARIA.
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BACKGROUND: The accumulation of soluble and insoluble aggregated amyloid-beta (Aß) may initiate or potentiate pathologic processes in Alzheimer's disease. Lecanemab, a humanized IgG1 monoclonal antibody that binds with high affinity to Aß soluble protofibrils, is being tested in persons with early Alzheimer's disease. METHODS: We conducted an 18-month, multicenter, double-blind, phase 3 trial involving persons 50 to 90 years of age with early Alzheimer's disease (mild cognitive impairment or mild dementia due to Alzheimer's disease) with evidence of amyloid on positron-emission tomography (PET) or by cerebrospinal fluid testing. Participants were randomly assigned in a 1:1 ratio to receive intravenous lecanemab (10 mg per kilogram of body weight every 2 weeks) or placebo. The primary end point was the change from baseline at 18 months in the score on the Clinical Dementia Rating-Sum of Boxes (CDR-SB; range, 0 to 18, with higher scores indicating greater impairment). Key secondary end points were the change in amyloid burden on PET, the score on the 14-item cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-cog14; range, 0 to 90; higher scores indicate greater impairment), the Alzheimer's Disease Composite Score (ADCOMS; range, 0 to 1.97; higher scores indicate greater impairment), and the score on the Alzheimer's Disease Cooperative Study-Activities of Daily Living Scale for Mild Cognitive Impairment (ADCS-MCI-ADL; range, 0 to 53; lower scores indicate greater impairment). RESULTS: A total of 1795 participants were enrolled, with 898 assigned to receive lecanemab and 897 to receive placebo. The mean CDR-SB score at baseline was approximately 3.2 in both groups. The adjusted least-squares mean change from baseline at 18 months was 1.21 with lecanemab and 1.66 with placebo (difference, -0.45; 95% confidence interval [CI], -0.67 to -0.23; P<0.001). In a substudy involving 698 participants, there were greater reductions in brain amyloid burden with lecanemab than with placebo (difference, -59.1 centiloids; 95% CI, -62.6 to -55.6). Other mean differences between the two groups in the change from baseline favoring lecanemab were as follows: for the ADAS-cog14 score, -1.44 (95% CI, -2.27 to -0.61; P<0.001); for the ADCOMS, -0.050 (95% CI, -0.074 to -0.027; P<0.001); and for the ADCS-MCI-ADL score, 2.0 (95% CI, 1.2 to 2.8; P<0.001). Lecanemab resulted in infusion-related reactions in 26.4% of the participants and amyloid-related imaging abnormalities with edema or effusions in 12.6%. CONCLUSIONS: Lecanemab reduced markers of amyloid in early Alzheimer's disease and resulted in moderately less decline on measures of cognition and function than placebo at 18 months but was associated with adverse events. Longer trials are warranted to determine the efficacy and safety of lecanemab in early Alzheimer's disease. (Funded by Eisai and Biogen; Clarity AD ClinicalTrials.gov number, NCT03887455.).
Subject(s)
Alzheimer Disease , Antibodies, Monoclonal, Humanized , Nootropic Agents , Humans , Activities of Daily Living , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/drug therapy , Amyloid beta-Peptides/cerebrospinal fluid , Antibodies, Monoclonal, Humanized/adverse effects , Antibodies, Monoclonal, Humanized/pharmacology , Antibodies, Monoclonal, Humanized/therapeutic use , Cognition/drug effects , Double-Blind Method , Nootropic Agents/adverse effects , Nootropic Agents/pharmacology , Nootropic Agents/therapeutic useABSTRACT
INTRODUCTION: The Alzheimer's disease (AD) continuum begins with a long asymptomatic or preclinical stage, during which amyloid beta (Aß) 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 Aß, 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 Aß 42/40 ratio (Aß 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.
Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Tauopathies , Humans , Middle Aged , Aged , Aged, 80 and over , Alzheimer Disease/diagnosis , Amyloid beta-Peptides/metabolism , Australia , Tauopathies/metabolism , Brain/diagnostic imaging , Brain/metabolism , Positron-Emission Tomography , Cognitive Dysfunction/metabolism , Biomarkers/metabolism , tau Proteins/metabolismABSTRACT
BACKGROUND: Lecanemab (BAN2401) is a humanized IgG1 monoclonal antibody that preferentially targets soluble aggregated Aß species (protofibrils) with activity at insoluble fibrils and slowed clinical decline in an 18-month phase 2 proof-of-concept study (Study 201; ClinicalTrials.gov NCT01767311) in 856 subjects with early Alzheimer's disease (AD). In this trial, subjects were randomized to five lecanemab dose regimens or placebo. The primary efficacy endpoint was change from baseline in the Alzheimer's Disease Composite Score (ADCOMS) at 12 months with Bayesian analyses. The key secondary endpoints were ADCOMS at 18 months and Clinical Dementia Rating-Sum-of-Boxes (CDR-SB) and Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog14) at 18 months. The results have been published previously. Herein, we describe the results of sensitivity analyses evaluating the consistency of the lecanemab efficacy results in Study 201 at the identified dose, the ED90, across multiple statistical methods and multiple endpoints over the duration of the study. METHODS: The protocol-specified analysis model was a mixed model for repeated measures (MMRM). Sensitivity analyses address the consistency of the conclusions using multiple statistical methods. These include a disease progression model (DPM), a natural cubic spline (NCS) model, a quadratic mixed model (QMM), and 2 MMRMs with additional covariates. RESULTS: The sensitivity analyses showed positive lecanemab treatment effects for all endpoints and all statistical models considered. The protocol-specified ADCOMS analysis showed a 29.7% slower decline than placebo for ADCOMS at 18 months. The various other analyses of 3 key endpoints showed declines ranging from 26.5 to 55.9%. The results at 12 months are also consistent with those at 18 months. CONCLUSIONS: The conclusion of the primary analysis of the lecanemab Study 201 is strengthened by the consistently positive conclusions across multiple statistical models, across efficacy endpoints, and over time, despite missing data. The 18-month data from this trial was utilized in the design of the confirmatory phase 3 trial (Clarity AD) and allowed for proper powering for multiple, robust outcomes.
Subject(s)
Alzheimer Disease , Humans , Bayes Theorem , Alzheimer Disease/drug therapy , Proof of Concept Study , Research DesignABSTRACT
BACKGROUND: Lecanemab, a humanized IgG1 monoclonal antibody that targets soluble aggregated Aß species (protofibrils), has demonstrated robust brain fibrillar amyloid reduction and slowing of clinical decline in early AD. The objective of this analysis is to report results from study 201 blinded period (core), the open-label extension (OLE), and gap period (between core and OLE) supporting the effectiveness of lecanemab. METHODS: The lecanemab study 201 core was a double-blind, randomized, placebo-controlled study of 856 patients randomized to one of five dose regimens or placebo. An OLE of study 201 was initiated to allow patients to receive open-label lecanemab 10mg/kg biweekly for up to 24 months, with an intervening off-treatment period (gap period) ranging from 9 to 59 months (mean 24 months). RESULTS: At 12 and 18 months of treatment in the core, lecanemab 10 mg/kg biweekly demonstrated dose-dependent reductions of brain amyloid measured PET and corresponding changes in plasma biomarkers and slowing of cognitive decline. The rates of clinical progression during the gap were similar in lecanemab and placebo subjects, with clinical treatment differences maintained after discontinued dosing over an average of 24 months in the gap period. During the gap, plasma Aß42/40 ratio and p-tau181 levels began to return towards pre-randomization levels more quickly than amyloid PET. At OLE baseline, treatment differences vs placebo at 18 months in the randomized period were maintained across 3 clinical assessments. In the OLE, lecanemab 10 mg/kg biweekly treatment produced dose-dependent reductions in amyloid PET SUVr, improvements in plasma Aß42/40 ratio, and reductions in plasma p-tau181. CONCLUSIONS: Lecanemab treatment resulted in significant reduction in amyloid plaques and a slowing of clinical decline. Data indicate that rapid and pronounced amyloid reduction correlates with clinical benefit and potential disease-modifying effects, as well as the potential to use plasma biomarkers to monitor for lecanemab treatment effects. TRIAL REGISTRATION: ClinicalTrials.gov NCT01767311 .
Subject(s)
Alzheimer Disease , Humans , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/drug therapy , Brain/diagnostic imaging , Antibodies, Monoclonal, Humanized/therapeutic use , Biomarkers , Amyloidogenic Proteins , Cognition , Amyloid beta-PeptidesABSTRACT
BACKGROUND: Clinicians, researchers, and patients alike would greatly benefit from more accessible and inexpensive biomarkers for neural ß-amyloid (Aß). We aimed to assess the performance of fully automated plasma Aß immunoassays, which correlate significantly with immunoprecipitation mass spectrometry assays, in predicting brain Aß status as determined by visual read assessment of amyloid positron emission tomography (PET). METHODS: The plasma Aß42/Aß40 ratio was measured using a fully automated immunoassay platform (HISCL series) in two clinical studies (discovery and validation studies). The discovery and validation sample sets were retrospectively and randomly selected from participants with early Alzheimer's disease (AD) identified during screening for the elenbecestat Phase 3 program. RESULTS: We included 197 participants in the discovery study (mean [SD] age 71.1 [8.5] years; 112 females) and 200 in the validation study (age 70.8 [7.9] years; 99 females). The plasma Aß42/Aß40 ratio predicted amyloid PET visual read status with areas under the receiver operating characteristic curves of 0.941 (95% confidence interval [CI] 0.910-0.973) and 0.868 (95% CI 0.816-0.920) in the discovery and validation studies, respectively. In the discovery study, a cutoff value of 0.102 was determined based on maximizing the Youden Index, and the sensitivity and specificity were calculated to be 96.0% (95% CI 90.1-98.9%) and 83.5% (95% CI 74.6-90.3%), respectively. Using the same cutoff value, the sensitivity and specificity in the validation study were calculated to be 88.0% (95% CI 80.0-93.6%) and 72.0% (95% CI 62.1-80.5%), respectively. CONCLUSIONS: The plasma Aß42/Aß40 ratio measured using the HISCL series achieved high accuracy in predicting amyloid PET status. Since our blood-based immunoassay system is less invasive and more accessible than amyloid PET and cerebrospinal fluid testing, it may contribute to the diagnosis of AD in routine clinical practice.
Subject(s)
Alzheimer Disease , Amyloidosis , Aged , Alzheimer Disease/diagnostic imaging , Amyloid , Amyloid beta-Peptides/cerebrospinal fluid , Biomarkers/cerebrospinal fluid , Female , Humans , Immunoassay , Peptide Fragments/cerebrospinal fluid , Positron-Emission Tomography , Retrospective StudiesABSTRACT
BACKGROUND: Lecanemab (BAN2401), an IgG1 monoclonal antibody, preferentially targets soluble aggregated amyloid beta (Aß), with activity across oligomers, protofibrils, and insoluble fibrils. BAN2401-G000-201, a randomized double-blind clinical trial, utilized a Bayesian design with response-adaptive randomization to assess 3 doses across 2 regimens of lecanemab versus placebo in early Alzheimer's disease, mild cognitive impairment due to Alzheimer's disease (AD) and mild AD dementia. METHODS: BAN2401-G000-201 aimed to establish the effective dose 90% (ED90), defined as the simplest dose that achieves ≥90% of the maximum treatment effect. The primary endpoint was Bayesian analysis of 12-month clinical change on the Alzheimer's Disease Composite Score (ADCOMS) for the ED90 dose, which required an 80% probability of ≥25% clinical reduction in decline versus placebo. Key secondary endpoints included 18-month Bayesian and frequentist analyses of brain amyloid reduction using positron emission tomography; clinical decline on ADCOMS, Clinical Dementia Rating-Sum-of-Boxes (CDR-SB), and Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog14); changes in CSF core biomarkers; and total hippocampal volume (HV) using volumetric magnetic resonance imaging. RESULTS: A total of 854 randomized subjects were treated (lecanemab, 609; placebo, 245). At 12 months, the 10-mg/kg biweekly ED90 dose showed a 64% probability to be better than placebo by 25% on ADCOMS, which missed the 80% threshold for the primary outcome. At 18 months, 10-mg/kg biweekly lecanemab reduced brain amyloid (-0.306 SUVr units) while showing a drug-placebo difference in favor of active treatment by 27% and 30% on ADCOMS, 56% and 47% on ADAS-Cog14, and 33% and 26% on CDR-SB versus placebo according to Bayesian and frequentist analyses, respectively. CSF biomarkers were supportive of a treatment effect. Lecanemab was well-tolerated with 9.9% incidence of amyloid-related imaging abnormalities-edema/effusion at 10 mg/kg biweekly. CONCLUSIONS: BAN2401-G000-201 did not meet the 12-month primary endpoint. However, prespecified 18-month Bayesian and frequentist analyses demonstrated reduction in brain amyloid accompanied by a consistent reduction of clinical decline across several clinical and biomarker endpoints. A phase 3 study (Clarity AD) in early Alzheimer's disease is underway. TRIAL REGISTRATION: Clinical Trials.gov NCT01767311 .
Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Alzheimer Disease/complications , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/drug therapy , Bayes Theorem , Brain , Double-Blind Method , HumansABSTRACT
Importance: Insomnia disorder is prevalent and associated with health risks in older adults; however, efficacy and safety issues with existing treatments create significant unmet needs in this patient population. Objective: To compare treatment with the orexin receptor antagonist lemborexant with placebo and zolpidem tartrate extended release in participants with insomnia disorder. Design, Setting, and Participants: The Study of the Efficacy and Safety of Lemborexant in Subjects 55 Years and Older With Insomnia Disorder (SUNRISE 1) clinical trial was a global randomized double-blind parallel-group placebo-controlled active-comparator phase 3 study conducted at 67 sites in North America and Europe from May 31, 2016, to January 30, 2018. Data analyses were conducted from January 31, 2018, to September 10, 2018. Participants were 55 years and older with insomnia disorder characterized by reported sleep maintenance difficulties and confirmed by sleep history, sleep diary, and polysomnography. Participants could have also had sleep onset difficulties. Interventions: Participants received placebo, zolpidem tartrate extended release (6.25 mg), or lemborexant (5 mg or 10 mg) for 1 month at bedtime. Main Outcomes and Measures: Paired polysomnograms were collected at baseline, the first 2 nights, and the last 2 nights of treatment. The primary end point was the change from baseline in latency to persistent sleep for lemborexant therapy vs placebo. Key secondary end points were changes from baseline in sleep efficiency and wake-after-sleep onset compared with placebo, and wake-after-sleep onset in the second half of the night compared with zolpidem therapy. Results: Among 1006 participants randomized (placebo, n = 208; zolpidem, n = 263; lemborexant 5 mg, n = 266; and lemborexant 10 mg, n = 269), 869 (86.4%) were women and the median age was 63 years (range, 55-88 years). Both doses of lemborexant therapy demonstrated statistically significant greater changes from baseline on objective sleep onset as assessed by latency to persistent sleep (log transformed) that was measured using polysomnography at the end of 1 month of treatment (nights 29 and 30) compared with placebo (primary end point for least squares geometric means treatment ratio vs placebo: for lemborexant 5 mg, 0.77; 95% CI, 0.67-0.89; P < .001; for lemborexant 10 mg, 0.72; 95% CI, 0.63-0.83; P < .001). For nights 29 and 30, as measured using polysomnography, the mean change from baseline in sleep efficiency (LSM treatment difference vs placebo for lemborexant 5 mg, 7.1%; 95% CI, 5.6%-8.5%; P < .001 and for lemborexant 10 mg, 8.0%; 95% CI, 6.6%-9.5%; P < .001) and wake-after-sleep onset (least squares mean treatment ratio vs placebo for lemborexant 5 mg, -24.0 min; 95% CI, -30.0 to -18.0 min; P < .001 and for lemborexant 10 mg, -25.4 min; 95% CI, -31.4 to -19.3 min; P < .001) were significantly greater for both doses of lemborexant therapy compared with placebo. Also, for nights 29 and 30, wake-after-sleep onset in the second half of the night (least squares mean treatment difference vs zolpidem for lemborexant 5 mg, -6.7 min; 95% CI, -11.2 to -2.2 min; P = .004 and for lemborexant 10 mg, -8.0 min; 95% CI, -12.5 to -3.5 min; P < .001) was significantly greater for both doses of lemborexant therapy compared with zolpidem therapy measured using polysomnography. Six participants (4 in the zolpidem group and 2 in the lemborexant 5 mg group) reported serious adverse events; none were treatment-related. Other adverse events were mostly mild or moderate in severity. Conclusions and Relevance: In this randomized clinical trial, lemborexant therapy significantly improved both sleep onset and sleep maintenance, including in the second half of the night, compared with both placebo and zolpidem measured objectively using polysomnography. Lemborexant therapy was well tolerated. Trial Registrations: ClinicalTrials.gov identifier: NCT02783729; EudraCT identifier: 2015-001463-39.
Subject(s)
Hypnotics and Sedatives/therapeutic use , Pyridines/therapeutic use , Pyrimidines/therapeutic use , Sleep Aids, Pharmaceutical/therapeutic use , Sleep Initiation and Maintenance Disorders/drug therapy , Zolpidem/therapeutic use , Aged , Delayed-Action Preparations , Double-Blind Method , Female , Humans , Male , Middle Aged , PolysomnographyABSTRACT
OBJECTIVE: Evaluate the long-term safety, tolerability, and behavioral effects of adjunctive rufinamide in pediatric patients (≥1 to <4 years old) with inadequately controlled seizures associated with Lennox-Gastaut syndrome (LGS). METHODS: Study 303 (ClinicalTrials.gov identifier NCT01405053) was a multicenter, randomized, open-label, Phase III trial. Patients were randomized (2:1) to oral suspension rufinamide (≤45 mg/kg/day) or any other investigator-chosen antiepileptic drug (AED) for a 2-year treatment period. Primary safety/tolerability assessments included monitoring of treatment-emergent adverse events (TEAEs) and serious TEAEs. Behavioral effects were assessed via the Child Behavior Checklist (CBCL) using the Total Problems score and change from baseline in CBCL Total Problems score. CBCL subscores were also evaluated. RESULTS: The Safety Analysis Set included 37 patients (rufinamide: n = 25; any other AED: n = 12). TEAE incidence was similar between the rufinamide (88.0%) and any-other-AED groups (83.3%); serious TEAE incidence was also similar between treatment groups (40.0% and 41.7%, respectively). Between treatment groups, the difference in the least squares mean CBCL Total Problems score across time was not significant (p = 0.7083), behavior outcomes were similar across all endpoints, and there were no consistent trends in CBCL subscores. SIGNIFICANCE: Long-term (2 years) adjunctive rufinamide was well tolerated in pediatric patients with LGS. Behavioral outcomes were comparable between the rufinamide and any-other-AED groups, however the small sample size and difficulties assessing behavior in this population should be noted. The challenges of this study raise the issue of revising how studies in very young children with rare and complex epilepsies are performed.
Subject(s)
Lennox Gastaut Syndrome/drug therapy , Triazoles/therapeutic use , Anticonvulsants/therapeutic use , Child , Child, Preschool , Female , Humans , MaleABSTRACT
BACKGROUND: There is a direct relationship between bodyweight and risk of diabetes. Lorcaserin, a selective serotonin 2C receptor agonist that suppresses appetite, has been shown to facilitate sustained weight loss in obese or overweight patients. We aimed to evaluate the long-term effects of lorcaserin on diabetes prevention and remission. METHODS: In this randomised, double-blind, placebo-controlled trial done in eight countries, we recruited overweight or obese patients (body-mass index ≥27 kg/m2) with or at high risk for atherosclerotic vascular disease. Eligible patients were aged 40 years or older; patients at high risk for atherosclerotic vascular disease had to be aged 50 years or older with diabetes and at least one other risk factor. Patients were randomly assigned to receive either lorcaserin (10 mg twice daily) or matching placebo. Additionally, all patients had access to a standardised weight management programme based on lifestyle modification. The prespecified primary metabolic efficacy endpoint of time to incident diabetes was assessed in patients with prediabetes at baseline. The prespecified secondary outcomes for efficacy were incident diabetes in all patients without diabetes, achievement of normoglycaemia in patients with prediabetes, and change in glycated haemoglobin (HbA1c) in patients with diabetes. Hypoglycaemia was a prespecified safety outcome. Analysis was by intention to treat, using Cox proportional hazard models for time-to-event analyses. This trial is registered with ClinicalTrials.gov, number NCT02019264. FINDINGS: Between Feb 7, 2014, and Nov 20, 2015, 12â000 patients were randomly assigned to lorcaserin or placebo (6000 patients in each group) and followed up for a median of 3·3 years (IQR 3·0-3·5). At baseline, 6816 patients (56·8%) had diabetes, 3991 (33·3%) prediabetes, and 1193 (9·9%) normoglycaemia. At 1 year, patients treated with lorcaserin had a net weight loss beyond placebo of 2·6 kg (95% CI 2·3-2·9) for those with diabetes, 2·8 kg (2·5-3·2) for those with prediabetes, and 3·3 kg (2·6-4·0) for those with normoglycaemia (p<0·0001 for all analyses). Lorcaserin reduced the risk of incident diabetes by 19% in patients with prediabetes (172 [8·5%] of 2015 vs 204 [10·3%] of 1976; hazard ratio 0·81, 95% CI 0·66-0·99; p=0·038) and by 23% in patients without diabetes (174 [6·7%] of 2615 vs 215 [8·4%] of 2569; 0·77, 0·63-0·94; p=0·012). Lorcaserin resulted in a non-significant increase in the rate of achievement of normoglycaemia in patients with prediabetes (185 [9·2%] vs 151 [7·6%]; 1·20, 0·97-1·49; p=0·093). In patients with diabetes, lorcaserin resulted in a reduction of 0·33% (95% CI 0·29-0·38; p<0·0001) in HbA1c compared with placebo at 1 year from a mean baseline of 53 mmol/mol (7·0%). In patients with diabetes at baseline, severe hypoglycaemia with serious complications was rare, but more common with lorcaserin (12 [0·4%] vs four [0·1%] events; p=0·054). INTERPRETATION: Lorcaserin decreases risk for incident diabetes, induces remission of hyperglycaemia, and reduces the risk of microvascular complications in obese and overweight patients, supporting the role of lorcaserin as an adjunct to lifestyle modification for chronic management of weight and metabolic health. FUNDING: Eisai.