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Honig LS, Sabbagh MN, van Dyck CH, Sperling RA, Hersch S, Matta A, Giorgi L, Gee M, Kanekiyo M, Li D, Purcell D, Dhadda S, Irizarry M, Kramer L. Updated safety results from phase 3 lecanemab study in early Alzheimer's disease. Alzheimers Res Ther 2024; 16:105. [PMID: 38730496 PMCID: PMC11084061 DOI: 10.1186/s13195-024-01441-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 03/31/2024] [Indexed: 05/13/2024]
Abstract
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 (Aβ)-directed antibody indicated for the treatment of early AD, binds with high affinity to soluble Aβ 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).
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Affiliation(s)
- Lawrence S Honig
- Columbia University Irving Medical Center, NYS Center of Excellence for Alzheimer's Disease, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Gertrude H. Sergievsky Center (PH19), & Department of Neurology, Columbia University Vagelos College of Physicians & Surgeons, 630 West 168th Street (P&S UNIT 16), New York, NY, 10032-3795, USA.
| | | | | | - Reisa A Sperling
- Brigham and Women's Hospital, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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Meyer MR, Kirmess KM, Eastwood S, Wente-Roth TL, Irvin F, Holubasch MS, Venkatesh V, Fogelman I, Monane M, Hanna L, Rabinovici GD, Siegel BA, Whitmer RA, Apgar C, Bateman RJ, Holtzman DM, Irizarry M, Verbel D, Sachdev P, Ito S, Contois J, Yarasheski KE, Braunstein JB, Verghese PB, West T. Clinical validation of the PrecivityAD2 blood test: A mass spectrometry-based test with algorithm combining %p-tau217 and Aβ42/40 ratio to identify presence of brain amyloid. Alzheimers Dement 2024. [PMID: 38491912 DOI: 10.1002/alz.13764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 01/25/2024] [Accepted: 01/31/2024] [Indexed: 03/18/2024]
Abstract
BACKGROUND With the availability of disease-modifying therapies for Alzheimer's disease (AD), it is important for clinicians to have tests to aid in AD diagnosis, especially when the presence of amyloid pathology is a criterion for receiving treatment. METHODS High-throughput, mass spectrometry-based assays were used to measure %p-tau217 and amyloid beta (Aβ)42/40 ratio in blood samples from 583 individuals with suspected AD (53% positron emission tomography [PET] positive by Centiloid > 25). An algorithm (PrecivityAD2 test) was developed using these plasma biomarkers to identify brain amyloidosis by PET. RESULTS The area under the receiver operating characteristic curve (AUC-ROC) for %p-tau217 (0.94) was statistically significantly higher than that for p-tau217 concentration (0.91). The AUC-ROC for the PrecivityAD2 test output, the Amyloid Probability Score 2, was 0.94, yielding 88% agreement with amyloid PET. Diagnostic performance of the APS2 was similar by ethnicity, sex, age, and apoE4 status. DISCUSSION The PrecivityAD2 blood test showed strong clinical validity, with excellent agreement with brain amyloidosis by PET.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Lucy Hanna
- Center for Statistical Sciences, Brown University School of Public Health, Providence, Rhode Island, USA
| | | | - Barry A Siegel
- School of Medicine, Washington University, St. Louis, Missouri, USA
| | | | - Charles Apgar
- American College of Radiology, Philadelphia, Pennsylvania, USA
| | | | - David M Holtzman
- School of Medicine, Washington University, St. Louis, Missouri, USA
| | | | | | | | | | | | | | | | | | - Tim West
- C2N Diagnostics, St. Louis, Missouri, USA
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Devanarayan V, Ye Y, Charil A, Andreozzi E, Sachdev P, Llano DA, Tian L, Zhu L, Hampel H, Kramer L, Dhadda S, Irizarry M. Predicting clinical progression trajectories of early Alzheimer's disease patients. Alzheimers Dement 2024; 20:1725-1738. [PMID: 38087949 PMCID: PMC10984448 DOI: 10.1002/alz.13565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 09/06/2023] [Accepted: 11/07/2023] [Indexed: 03/16/2024]
Abstract
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.
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Affiliation(s)
- Viswanath Devanarayan
- Clinical Evidence GenerationEisai Inc.NutleyNew JerseyUSA
- Department of MathematicsStatistics and Computer ScienceUniversity of Illinois ChicagoChicagoIllinoisUSA
| | - Yuanqing Ye
- Clinical Evidence GenerationEisai Inc.NutleyNew JerseyUSA
| | - Arnaud Charil
- Clinical Evidence GenerationEisai Inc.NutleyNew JerseyUSA
| | | | | | - Daniel A. Llano
- Carle Illinois College of MedicineUrbanaIllinoisUSA
- Department of Molecular and Integrative PhysiologyUniversity of Illinois Urbana‐ChampaignUrbanaIllinoisUSA
| | - Lu Tian
- Department of Biomedical Data ScienceStanford University School of MedicinePalo AltoCaliforniaUSA
| | - Liang Zhu
- Clinical Evidence GenerationEisai Inc.NutleyNew JerseyUSA
| | - Harald Hampel
- Clinical Evidence GenerationEisai Inc.NutleyNew JerseyUSA
| | - Lynn Kramer
- Clinical Evidence GenerationEisai Inc.NutleyNew JerseyUSA
| | - Shobha Dhadda
- Clinical Evidence GenerationEisai Inc.NutleyNew JerseyUSA
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Rissman RA, Langford O, Raman R, Donohue MC, Abdel‐Latif S, Meyer MR, Wente‐Roth T, Kirmess KM, Ngolab J, Winston CN, Jimenez‐Maggiora G, Rafii MS, Sachdev P, West T, Yarasheski KE, Braunstein JB, Irizarry M, Johnson KA, Aisen PS, Sperling RA. Plasma Aβ42/Aβ40 and phospho-tau217 concentration ratios increase the accuracy of amyloid PET classification in preclinical Alzheimer's disease. Alzheimers Dement 2024; 20:1214-1224. [PMID: 37932961 PMCID: PMC10916957 DOI: 10.1002/alz.13542] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 09/15/2023] [Accepted: 09/28/2023] [Indexed: 11/08/2023]
Abstract
INTRODUCTION Incorporating blood-based Alzheimer's disease biomarkers such as tau and amyloid beta (Aβ) into screening algorithms may improve screening efficiency. METHODS Plasma Aβ, phosphorylated tau (p-tau)181, and p-tau217 concentration levels from AHEAD 3-45 study participants were measured using mass spectrometry. Tau concentration ratios for each proteoform were calculated to normalize for inter-individual differences. Receiver operating characteristic (ROC) curve analysis was performed for each biomarker against amyloid positivity, defined by > 20 Centiloids. Mixture of experts analysis assessed the value of including tau concentration ratios into the existing predictive algorithm for amyloid positron emission tomography status. RESULTS The area under the receiver operating curve (AUC) was 0.87 for Aβ42/Aβ40, 0.74 for phosphorylated variant p-tau181 ratio (p-tau181/np-tau181), and 0.92 for phosphorylated variant p-tau217 ratio (p-tau217/np-tau217). The Plasma Predicted Centiloid (PPC), a predictive model including p-tau217/np-tau217, Aβ42/Aβ40, age, and apolipoprotein E improved AUC to 0.95. DISCUSSION Including plasma p-tau217/np-tau217 along with Aβ42/Aβ40 in predictive algorithms may streamline screening preclinical individuals into anti-amyloid clinical trials. CLINICALTRIALS gov Identifier: NCT04468659 HIGHLIGHTS: The addition of plasma phosphorylated variant p-tau217 ratio (p-tau217/np-tau217) significantly improved plasma biomarker algorithms for identifying preclinical amyloid positron emission tomography positivity. Prediction performance at higher NAV Centiloid levels was improved with p-tau217/np-tau217. All models generated for this study are incorporated into the Plasma Predicted Centiloid (PPC) app for public use.
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Affiliation(s)
- Robert A. Rissman
- Department of NeurosciencesUniversity of California San DiegoLa JollaCaliforniaUSA
- Alzheimer's Therapeutic Research InstituteKeck School of Medicine of the University of Southern CaliforniaSan DiegoCaliforniaUSA
- VA San Diego Healthcare SystemSan DiegoCaliforniaUSA
| | - Oliver Langford
- Alzheimer's Therapeutic Research InstituteKeck School of Medicine of the University of Southern CaliforniaSan DiegoCaliforniaUSA
| | - Rema Raman
- Alzheimer's Therapeutic Research InstituteKeck School of Medicine of the University of Southern CaliforniaSan DiegoCaliforniaUSA
| | - Michael C. Donohue
- Alzheimer's Therapeutic Research InstituteKeck School of Medicine of the University of Southern CaliforniaSan DiegoCaliforniaUSA
| | - Sara Abdel‐Latif
- Alzheimer's Therapeutic Research InstituteKeck School of Medicine of the University of Southern CaliforniaSan DiegoCaliforniaUSA
| | | | | | | | - Jennifer Ngolab
- Alzheimer's Therapeutic Research InstituteKeck School of Medicine of the University of Southern CaliforniaSan DiegoCaliforniaUSA
| | - Charisse N. Winston
- Department of NeurosciencesUniversity of California San DiegoLa JollaCaliforniaUSA
- Alzheimer's Therapeutic Research InstituteKeck School of Medicine of the University of Southern CaliforniaSan DiegoCaliforniaUSA
| | - Gustavo Jimenez‐Maggiora
- Alzheimer's Therapeutic Research InstituteKeck School of Medicine of the University of Southern CaliforniaSan DiegoCaliforniaUSA
| | - Michael S. Rafii
- Alzheimer's Therapeutic Research InstituteKeck School of Medicine of the University of Southern CaliforniaSan DiegoCaliforniaUSA
| | | | - Tim West
- C2N DiagnosticsSt. LouisMissouriUSA
| | | | | | | | - Keith A. Johnson
- Brigham and Women's Hospital, Massachusetts General HospitalHarvard Medical SchoolBostonMassachusettsUSA
| | - Paul S. Aisen
- Alzheimer's Therapeutic Research InstituteKeck School of Medicine of the University of Southern CaliforniaSan DiegoCaliforniaUSA
| | - Reisa A. Sperling
- Brigham and Women's Hospital, Massachusetts General HospitalHarvard Medical SchoolBostonMassachusettsUSA
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Grill JD, Flournoy C, Dhadda S, Ernstrom K, Sperling R, Molina-Henry D, Tranotti K, Harris R, Kanekiyo M, Gee M, Irizarry M, Kramer L, Aisen P, Raman R. Eligibility Rates among Racially and Ethnically Diverse US Participants in Phase 2 and Phase 3 Placebo-Controlled, Double-Blind, Randomized Trials of Lecanemab and Elenbecestat in Early Alzheimer Disease. Ann Neurol 2024; 95:288-298. [PMID: 37830926 DOI: 10.1002/ana.26819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 10/08/2023] [Accepted: 10/09/2023] [Indexed: 10/14/2023]
Abstract
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.
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Affiliation(s)
- Joshua D Grill
- Institute for Memory Impairments and Neurological Disorders, Departments of Psychiatry and Human Behavior and Neurobiology and Behavior, University of California, Irvine, Irvine, CA, USA
| | - Charlene Flournoy
- Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego, CA, USA
| | | | - Karin Ernstrom
- Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego, CA, USA
| | - Reisa Sperling
- Brigham and Women's Hospital, Massachusetts General Hospital, Boston, MA, USA
| | - Doris Molina-Henry
- Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego, CA, USA
| | | | | | | | | | | | | | - Paul Aisen
- Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego, CA, USA
| | - Rema Raman
- Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego, CA, USA
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Tahami Monfared AA, Stern Y, Doogan S, Irizarry M, Zhang Q. Understanding Barriers Along the Patient Journey in Alzheimer's Disease Using Social Media Data. Neurol Ther 2023; 12:899-918. [PMID: 37060417 PMCID: PMC10195971 DOI: 10.1007/s40120-023-00472-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 03/21/2023] [Indexed: 04/16/2023] Open
Abstract
INTRODUCTION We speculated that social media data from Alzheimer's disease (AD) stakeholders (patients, caregivers, and clinicians) could identify barriers along the patient journey in AD, and that insights gained may help devise strategies to remove barriers, and ultimately improve the patient journey. METHODS Our sample was drawn from a repository of social media posts extracted from 112 public sources between January 1998 and December 2021 using natural language processing text-mining algorithms. The patient journey was classified into three phases: (1) early signs/experiences (Early Signs); (2) screening/assessment/diagnosis (Screening); and (3) treatment/management (Treatment). In the Early Signs phase, issues/challenges derived from a conceptual AD identification framework (ADIF) were examined. In subsequent phases, behavioral/psychiatric challenges, access/barriers to health care, screening/diagnostic methods, and symptomatic treatments for AD were identified. Posts were classified by AD stakeholder type or disease stage, if possible. RESULTS We identified 225,977 AD patient journey-related social media posts. Anxiety was a predominant issue/challenge in all patient journey phases. In the Screening and Treatment phases combined, access/barriers to care were described in 16% of posts; unwillingness/resistance to seeking care was a major barrier (≥ 75% of access-related posts across all stakeholders). Commonly identified structural barriers (e.g., affordability/cost, geography/transportation/distance) were more common in patient/caregiver posts than clinician posts. Among Screening-related posts, imaging/scans were commonly mentioned by all stakeholders; biomarkers were more commonly mentioned by patients than clinicians. Treatment-related concerns were identified in 17% of stakeholder-specified posts that named pharmacological agents/classes for the symptomatic management of AD. CONCLUSION This descriptive analysis of out-of-clinic experiences reflected in AD social media posts found that unwillingness/resistance to seeking care was a key barrier, followed by structural barriers to health care, such as affordability/cost. Insights from the lived experiences of AD stakeholders are valuable and highlight the need to improve the patient journey in AD and ease patient and caregiver burden.
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Affiliation(s)
- Amir Abbas Tahami Monfared
- Eisai, Inc., 200 Metro Blvd, Nutley, NJ, 07110, USA.
- Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC, Canada.
| | - Yaakov Stern
- Cognitive Neuroscience Division, Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, USA
| | | | | | - Quanwu Zhang
- Eisai, Inc., 200 Metro Blvd, Nutley, NJ, 07110, USA
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Berry DA, Dhadda S, Kanekiyo M, Li D, Swanson CJ, Irizarry M, Kramer LD, Berry SM. Lecanemab for Patients With Early Alzheimer Disease: Bayesian Analysis of a Phase 2b Dose-Finding Randomized Clinical Trial. JAMA Netw Open 2023; 6:e237230. [PMID: 37040116 PMCID: PMC10091161 DOI: 10.1001/jamanetworkopen.2023.7230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/12/2023] Open
Abstract
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.
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Affiliation(s)
| | | | | | - David Li
- Eisai Inc, Woodcliff Lake, New Jersey
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Langbaum JB, Zissimopoulos J, Au R, Bose N, Edgar CJ, Ehrenberg E, Fillit H, Hill CV, Hughes L, Irizarry M, Kremen S, Lakdawalla D, Lynn N, Malzbender K, Maruyama T, Massett HA, Patel D, Peneva D, Reiman EM, Romero K, Routledge C, Weiner MW, Weninger S, Aisen PS. Recommendations to address key recruitment challenges of Alzheimer's disease clinical trials. Alzheimers Dement 2023; 19:696-707. [PMID: 35946590 PMCID: PMC9911558 DOI: 10.1002/alz.12737] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 05/26/2022] [Accepted: 06/14/2022] [Indexed: 11/10/2022]
Abstract
Clinical trials for Alzheimer's disease (AD) are slower to enroll study participants, take longer to complete, and are more expensive than trials in most other therapeutic areas. The recruitment and retention of a large number of qualified, diverse volunteers to participate in clinical research studies remain among the key barriers to the successful completion of AD clinical trials. An advisory panel of experts from academia, patient-advocacy organizations, philanthropy, non-profit, government, and industry convened in 2020 to assess the critical challenges facing recruitment in Alzheimer's clinical trials and develop a set of recommendations to overcome them. This paper briefly reviews existing challenges in AD clinical research and discusses the feasibility and implications of the panel's recommendations for actionable and inclusive solutions to accelerate the development of novel therapies for AD.
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Affiliation(s)
| | - Julie Zissimopoulos
- Sol Price School of Public Policy and Leonard D. Schaeffer Center for Health Policy and Economics, University of Southern California, Los Angeles, California, USA
| | - Rhoda Au
- Departments of Anatomy & Neurobiology, Neurology and Epidemiology, Boston University Schools of Medicine and Public Health, Boston, Massachusetts, USA
| | | | | | | | - Howard Fillit
- Alzheimer’s Drug Discovery Foundation, New York, New York, USA
| | | | | | | | - Sarah Kremen
- The Jona Goldrich Center for Alzheimer’s and Memory Disorders, Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Darius Lakdawalla
- Leonard D. Schaeffer Center for Health Policy and Economics, University of Southern California, Los Angeles, California, USA
| | - Nancy Lynn
- BrightFocus Foundation, Clarksburg, Maryland, USA
| | | | | | | | | | - Desi Peneva
- Leonard D. Schaeffer Center for Health Policy and Economics, University of Southern California, Los Angeles, California, USA
| | | | | | | | - Michael W. Weiner
- Departments of Radiology and Biomedical Imaging, Medicine, Psychiatry, and Neurology, University of California San Francisco, San Francisco, California, USA
| | | | - Paul S. Aisen
- Alzheimer’s Therapeutic Research Institute, University of Southern California, San Diego, California, USA
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van Dyck CH, Swanson CJ, Aisen P, Bateman RJ, Chen C, Gee M, Kanekiyo M, Li D, Reyderman L, Cohen S, Froelich L, Katayama S, Sabbagh M, Vellas B, Watson D, Dhadda S, Irizarry M, Kramer LD, Iwatsubo T. Lecanemab in Early Alzheimer's Disease. N Engl J Med 2023; 388:9-21. [PMID: 36449413 DOI: 10.1056/nejmoa2212948] [Citation(s) in RCA: 1037] [Impact Index Per Article: 1037.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
BACKGROUND The accumulation of soluble and insoluble aggregated amyloid-beta (Aβ) may initiate or potentiate pathologic processes in Alzheimer's disease. Lecanemab, a humanized IgG1 monoclonal antibody that binds with high affinity to Aβ 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.).
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Affiliation(s)
- Christopher H van Dyck
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Chad J Swanson
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Paul Aisen
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Randall J Bateman
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Christopher Chen
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Michelle Gee
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Michio Kanekiyo
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - David Li
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Larisa Reyderman
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Sharon Cohen
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Lutz Froelich
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Sadao Katayama
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Marwan Sabbagh
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Bruno Vellas
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - David Watson
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Shobha Dhadda
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Michael Irizarry
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Lynn D Kramer
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
| | - Takeshi Iwatsubo
- From the Alzheimer's Disease Research Unit, Yale School of Medicine, New Haven, CT (C.H.D.); Eisai, Nutley, NJ (C.J.S., M.K., D.L., L.R., S.D., M.I., L.D.K.); the Alzheimer's Therapeutic Research Institute, University of Southern California, San Diego (P.A.); Washington University School of Medicine in St. Louis, St. Louis (R.B.); the Memory, Aging, and Cognition Center, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.C.); Eisai, Hatfield, United Kingdom (M.G.); Toronto Memory Program, Toronto (S.C.); Medical Faculty Mannheim, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany (L.F.); Katayama Medical Clinic, Okayama (S.K.), and the Department of Neuropathology, Graduate School of Medicine, University of Tokyo, and the National Center of Neurology and Psychiatry, Tokyo (T.I.) - all in Japan; Barrow Neurological Institute, Phoenix, AZ (M.S.); Toulouse Gerontopole University Hospital, Université Paul Sabatier, INSERM Unité 1295, Toulouse, France (B.V.); and Alzheimer's Research and Treatment Center, Wellington, FL (D.W.)
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Honig LS, Barakos J, Dhadda S, Kanekiyo M, Reyderman L, Irizarry M, Kramer LD, Swanson CJ, Sabbagh M. ARIA in patients treated with lecanemab (BAN2401) in a phase 2 study in early Alzheimer's disease. Alzheimers Dement (N Y) 2023; 9:e12377. [PMID: 36949897 PMCID: PMC10026083 DOI: 10.1002/trc2.12377] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 01/25/2023] [Accepted: 02/10/2023] [Indexed: 03/24/2023]
Abstract
INTRODUCTION Lecanemab is a humanized immunoglobulin G1 (IgG1) monoclonal antibody that preferentially targets soluble aggregated Aβ 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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Affiliation(s)
- Lawrence S. Honig
- Department of Neurology and Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Jerome Barakos
- California Pacific Medical CenterSan FranciscoCaliforniaUSA
- Clario Inc.San MateoCaliforniaUSA
| | - Shobha Dhadda
- Alzheimer's Disease and Brain HealthEisai Inc.NutleyNew JerseyUSA
| | - Michio Kanekiyo
- Alzheimer's Disease and Brain HealthEisai Inc.NutleyNew JerseyUSA
| | - Larisa Reyderman
- Alzheimer's Disease and Brain HealthEisai Inc.NutleyNew JerseyUSA
| | - Michael Irizarry
- Alzheimer's Disease and Brain HealthEisai Inc.NutleyNew JerseyUSA
| | - Lynn D. Kramer
- Alzheimer's Disease and Brain HealthEisai Inc.NutleyNew JerseyUSA
| | - Chad J. Swanson
- Alzheimer's Disease and Brain HealthEisai Inc.NutleyNew JerseyUSA
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11
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Cohen S, van Dyck CH, Gee M, Doherty T, Kanekiyo M, Dhadda S, Li D, Hersch S, Irizarry M, Kramer LD. Lecanemab Clarity AD: Quality-of-Life Results from a Randomized, Double-Blind Phase 3 Trial in Early Alzheimer's Disease. J Prev Alzheimers Dis 2023; 10:771-777. [PMID: 37874099 DOI: 10.14283/jpad.2023.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
BACKGROUND Lecanemab is a humanized IgG1 monoclonal antibody binding with high affinity to amyloid-beta protein protofibrils. In phase 3 development, lecanemab has been shown to reduce markers of amyloid in early Alzheimer's disease and reduce decline on clinical endpoints of cognition and function at 18 months. OBJECTIVES To describe the health-related quality-of-life (HRQoL) results from Clarity AD which were exploratory outcomes in this trial. DESIGN Clarity AD was an 18-month, multi-center, double-blind, phase 3 trial. SETTING Early Alzheimer's disease. PARTICIPANTS Individuals 50-90 years of age with a diagnosis of mild cognitive impairment or mild dementia due to Alzheimer's disease and positron emission tomography or cerebrospinal fluid evidence of cerebral amyloid accumulation. INTERVENTION Placebo or lecanemab 10-mg/kg IV biweekly. MEASUREMENTS HRQoL was measured at baseline and every 6 months using the European Quality of Life-5 Dimensions (EQ-5D-5L; by subject) and Quality of Life in AD (QOL-AD; by subject and proxy). Study partner burden was measured using the Zarit Burden Interview (ZBI). RESULTS A total of 1795 participants were enrolled (lecanemab:898; placebo:897). At month 18, adjusted mean change from baseline in EQ-5D-5L and QOL-AD by subject showed 49% and 56% less decline, respectively. QOL-AD rated by study partner as proxy resulted in 23% less decline. ZBI adjusted mean change from baseline at 18 months resulted in 38% less increase of care partner burden. Individual HRQoL test items and dimensions also showed lecanemab benefit. CONCLUSIONS Lecanemab was associated with a relative preservation of HRQoL and less increase in caregiver burden, with consistent benefits seen across different quality of life scales and within scale subdomains. These benefits provide valuable patient reported outcomes which, together with previously reported benefits of lecanemab across multiple measures of cognition, function, disease progression, and biomarkers, demonstrate that lecanemab treatment may offer meaningful benefits to patients, care partners, and society.
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Affiliation(s)
- S Cohen
- Sharon Cohen, MD, FRCPC, Medical Director and Site Principal Investigator, 1 Valleybrook Drive, Suite 400, Toronto, Canada M3B 2S7, Tel: 416-386-9761; Fax: 416-386-0458,
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12
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McDade E, Cummings JL, Dhadda S, Swanson CJ, Reyderman L, Kanekiyo M, Koyama A, Irizarry M, Kramer LD, Bateman RJ. Lecanemab in patients with early Alzheimer's disease: detailed results on biomarker, cognitive, and clinical effects from the randomized and open-label extension of the phase 2 proof-of-concept study. Alzheimers Res Ther 2022; 14:191. [PMID: 36544184 PMCID: PMC9768996 DOI: 10.1186/s13195-022-01124-2] [Citation(s) in RCA: 64] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Accepted: 11/17/2022] [Indexed: 12/24/2022]
Abstract
BACKGROUND Lecanemab, a humanized IgG1 monoclonal antibody that targets soluble aggregated Aβ 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 Aβ42/40 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 Aβ42/40 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 .
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Affiliation(s)
- Eric McDade
- grid.4367.60000 0001 2355 7002The DIAN–TU, Department of Neurology, Washington University School of Medicine, St. Louis, MO USA
| | - Jeffrey L. Cummings
- grid.272362.00000 0001 0806 6926Chambers-Grundy Center for Transformative Neuroscience, Quirk Brain Health and Biomarker Laboratory, Department of Brain Health, School of Integrated Health Sciences, University of Nevada Las Vegas, Las Vegas, NV USA
| | - Shobha Dhadda
- grid.418767.b0000 0004 0599 8842Eisai Inc., Nutley, NJ USA
| | | | | | | | - Akihiko Koyama
- grid.418767.b0000 0004 0599 8842Eisai Inc., Nutley, NJ USA
| | | | - Lynn D. Kramer
- grid.418767.b0000 0004 0599 8842Eisai Inc., Nutley, NJ USA
| | - Randall J. Bateman
- grid.4367.60000 0001 2355 7002The DIAN–TU, Department of Neurology, Washington University School of Medicine, St. Louis, MO USA
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Dhadda S, Kanekiyo M, Li D, Swanson CJ, Irizarry M, Berry S, Kramer LD, Berry DA. Consistency of efficacy results across various clinical measures and statistical methods in the lecanemab phase 2 trial of early Alzheimer's disease. Alzheimers Res Ther 2022; 14:182. [PMID: 36482412 PMCID: PMC9733166 DOI: 10.1186/s13195-022-01129-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 11/21/2022] [Indexed: 12/13/2022]
Abstract
BACKGROUND Lecanemab (BAN2401) is a humanized IgG1 monoclonal antibody that preferentially targets soluble aggregated Aβ 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.
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Affiliation(s)
- Shobha Dhadda
- grid.418767.b0000 0004 0599 8842Eisai Inc, Nutley, NJ USA
| | | | - David Li
- grid.418767.b0000 0004 0599 8842Eisai Inc, Nutley, NJ USA
| | | | | | | | - Lynn D. Kramer
- grid.418767.b0000 0004 0599 8842Eisai Inc, Nutley, NJ USA
| | - Donald A. Berry
- Berry Consultants, LLC, Austin, TX USA ,grid.240145.60000 0001 2291 4776University of Texas M.D. Anderson Cancer Center, Houston, TX USA
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Bullich S, Mueller A, De Santi S, Koglin N, Krause S, Kaplow J, Kanekiyo M, Roé-Vellvé N, Perrotin A, Jovalekic A, Scott D, Gee M, Stephens A, Irizarry M. Evaluation of tau deposition using 18F-PI-2620 PET in MCI and early AD subjects—a MissionAD tau sub-study. Alzheimers Res Ther 2022; 14:105. [PMID: 35897078 PMCID: PMC9327167 DOI: 10.1186/s13195-022-01048-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 07/11/2022] [Indexed: 11/10/2022]
Abstract
Background The ability of 18F-PI-2620 PET to measure the spatial distribution of tau pathology in Alzheimer’s disease (AD) has been demonstrated in previous studies. The objective of this work was to evaluate tau deposition using 18F-PI-2620 PET in beta-amyloid positive subjects with a diagnosis of mild cognitive impairment (MCI) or mild AD dementia and characterize it with respect to amyloid deposition, cerebrospinal fluid (CSF) assessment, hippocampal volume, and cognition. Methods Subjects with a diagnosis of MCI due to AD or mild AD dementia and a visually amyloid-positive 18F-florbetaben PET scan (n=74, 76 ± 7 years, 38 females) underwent a baseline 18F-PI-2620 PET, T1-weighted magnetic resonance imaging (MRI), CSF assessment (Aβ42/Aβ40 ratio, p-tau, t-tau) (n=22) and several cognitive tests. A 1-year follow-up 18F-PI-2620 PET scans and cognitive assessments were done in 15 subjects. Results Percentage of visually tau-positive scans increased with amyloid-beta deposition measured in 18F-florbetaben Centiloids (CL) (7.7% (<36 CL), 80% (>83 CL)). 18F-PI-2620 standardized uptake value ratio (SUVR) was correlated with increased 18F-florbetaben CL in several regions of interest. Elevated 18F-PI-2620 SUVR (fusiform gyrus) was associated to high CSF p-tau and t-tau (p=0.0006 and p=0.01, respectively). Low hippocampal volume was associated with increased tau load at baseline (p=0.006 (mesial temporal); p=0.01 (fusiform gyrus)). Significant increases in tau SUVR were observed after 12 months, particularly in the mesial temporal cortex, fusiform gyrus, and inferior temporal cortex (p=0.04, p=0.047, p=0.02, respectively). However, no statistically significant increase in amyloid-beta load was measured over the observation time. The MMSE (Recall score), ADAS-Cog14 (Word recognition score), and CBB (One-card learning score) showed the strongest association with tau deposition at baseline. Conclusions The findings support the hypothesis that 18F-PI-2620 PET imaging of neuropathologic tau deposits may reflect underlying neurodegeneration in AD with significant correlations with hippocampal volume, CSF biomarkers, and amyloid-beta load. Furthermore, quantifiable increases in 18F-PI-2620 SUVR over a 12-month period in regions with early tau deposition are consistent with the hypothesis that cortical tau is associated with cognitive impairment. This study supports the utility of 18F-PI-2620 PET to assess tau deposits in an early AD population. Quantifiable tau load and its corresponding increase in early AD cases could be a relevant target engagement marker in clinical trials of anti-amyloid and anti-tau agents. Trial registration Data used in this manuscript belong to a tau PET imaging sub-study of the elenbecestat MissionAD Phase 3 program registered in ClinicalTrials.gov (NCT02956486; NCT03036280). Supplementary Information The online version contains supplementary material available at 10.1186/s13195-022-01048-x.
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Tahami Monfared AA, Stern Y, Doogan S, Irizarry M, Zhang Q. Stakeholder Insights in Alzheimer's Disease: Natural Language Processing of Social Media Conversations. J Alzheimers Dis 2022; 89:695-708. [PMID: 35938254 DOI: 10.3233/jad-220422] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Social media data may be especially effective for studying diseases associated with high stigma, such as Alzheimer's disease (AD). OBJECTIVE We primarily aimed to identify issues/challenges experienced by patients with AD using natural language processing (NLP) of social media posts. METHODS We searched 130 public social media sources between January 1998 and December 2021 for AD stakeholder social media posts using NLP to identify issues/challenges experienced by patients with AD. Issues/challenges identified by ≥10% of any AD stakeholder type were described. Illustrative posts were selected for qualitative review. Secondarily, issues/challenges were organized into a conceptual AD identification framework (ADIF) and representation of ADIF categories within clinical instruments was assessed. RESULTS We analyzed 1,859,077 social media posts from 30,341 AD stakeholders (21,011 caregivers; 7,440 clinicians; 1,890 patients). The most common issues/challenges were Worry/anxiety (34.2%), Pain (33%), Malaise (28.7%), Confusional state (27.1%), and Falls (23.9%). Patients reported a markedly higher volume of issues/challenges than other stakeholders. Patient posts reflected the broader scope of patient burden, caregiver posts captured both patient and caregiver burden, and clinician posts tended to be targeted. Less than 5% of the high frequency issues/challenges were in the "function and independence" and "social and relational well-being" categories of the ADIF, suggesting these issues/challenges may be difficult to capture. No single clinical instrument covered all ADIF categories; "social and relational well-being" was least represented. CONCLUSION NLP of AD stakeholder social media data revealed a broad spectrum of real-world insights regarding patient burden.
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Affiliation(s)
- Amir Abbas Tahami Monfared
- Eisai, Inc., Nutley, NJ, USA.,McGill University, Epidemiology, Biostatistics and Occupational Health, Montreal (QC), Canada
| | - Yaakov Stern
- Cognitive Neuroscience Division, Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
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Doherty T, Gee M, Maruff P, Smith R, Murphy J, Marsh J, Koschalka L, Martinez M, Irizarry M, Albala B. Increasing the Cognitive Screening Efficiency of Global Phase III Trials in Early Alzheimer Disease: The Cognitive Task Force. Alzheimer Dis Assoc Disord 2022; 36:185-191. [PMID: 35622461 DOI: 10.1097/wad.0000000000000508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 02/27/2022] [Indexed: 11/26/2022]
Abstract
PURPOSE A Cognitive Task Force (CTF) was established for the MissionAD program with the aim of reducing the screen failure (SF) rate to ∼30% and thereby reduce unnecessary subject burden, site burden, and excess trial costs. METHODS/SUBJECTS The MissionAD program consisted of 2 global phase 3 studies evaluating the BACE inhibitor elenbecestat in subjects with early Alzheimer disease. The CTF monitored and engaged with MissionAD clinical sites to provide support through collegial discussions to maximize the efficiency of the preconsent recruitment phase. RESULTS The CTF significantly improved cognitive screening efficiency in the MissionAD program, with a 24% decline in cognitive SF rate for the sites that the CTF contacted. The study-wide 11.5% reduction in cognitive SF rates were likely further driven by wider country-level initiatives in which CTF members held CTF-specific Investigator meetings with the recruitment staff, speaking to all sites on a country level regardless of their recruitment performance. CONCLUSIONS The establishment of a CTF to support efficient cognitive screening is highly recommended for future Alzheimer disease studies. Additional benefits included improved site relationships, increased engagement in MissionAD and access to a group of cognitive experts for consulting, with a focus on achieving more efficient trial recruitment.
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Affiliation(s)
- Thomas Doherty
- School of Life Sciences, University of Westminster, London
- Eisai Ltd, Hatfield, UK
| | | | | | | | | | | | | | | | | | - Bruce Albala
- School of Medicine, University of California Irvine, Irvine, CA
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Morin P, Li M, Wang Y, Aguilar BJ, Berlowitz D, Tahami Monfared AA, Irizarry M, Zhang Q, Xia W. Clinical Staging of Alzheimer's Disease: Concordance of Subjective and Objective Assessments in the Veteran's Affairs Healthcare System. Neurol Ther 2022; 11:1341-1352. [PMID: 35778542 PMCID: PMC9338180 DOI: 10.1007/s40120-022-00379-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 06/09/2022] [Indexed: 11/29/2022] Open
Abstract
INTRODUCTION Uncertainty surrounding the accurate assessment of the early-stage Alzheimer's disease (AD) may cause delayed care and inappropriate patient access to new AD therapies. METHODS To analyze clinical assessments of patients with AD in the Veteran's Affairs (VA) Healthcare System and evaluate concordance between subjective and objective assessments, we processed clinical notes extracted by text integration utilities between April 1, 2008 and October 14, 2021. Veterans who had mild, moderate, or severe AD with clinical notes documenting both clinician's judgement of AD severity and objective test scores from the Mini-Mental State Examination or the Montreal Cognitive Assessment were included. Using clinician-defined severity cohorts, we determined concordance between the clinician's (subjective) assessments and the test-derived (objective) assessments of AD severity. Concordance was assessed over time and by selected symptoms and comorbidities, as well as healthcare system factors. RESULTS A total of 8888 notes were initially extracted; the final analysis sample included 7514 notes corresponding to 4469 unique patients (mean [standard deviation] age of 78 [9] years; 96.5% male; 77.8% White). Subjective and objective assessments were concordant in approximately half (53%) of overall notes. In the mild Alzheimer's cohort, patients were assessed to have more severe disease by objective test scores in 40% of notes. Concordance varied about 21-73%, 47-58%, and 40-64% across symptoms/comorbidities, clinician types, and Veteran's Integrated Service Networks, respectively. The proportion of concordant notes was higher in visits to dementia (61%) instead of non-dementia clinics (53%). CONCLUSIONS We found higher concordance between clinician's assessment and test-based assessment of Alzheimer's disease severity in dementia specialty clinics. Discordance is especially high for the subjectively assessed mild AD cohort where objective assessments showed a higher severity level in 40% of notes. These data indicate a critical need for improved understanding of clinical assessments and decision-making to identify appropriate patients for anti-amyloid therapy.
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Affiliation(s)
- Peter Morin
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA
| | - Mingfei Li
- Department of Mathematical Sciences, Bentley University, Waltham, MA, USA.,Center for Healthcare Organization and Implementation Research, Bedford VA Healthcare System, Bedford, MA, USA
| | - Ying Wang
- Department of Mathematical Sciences, Bentley University, Waltham, MA, USA.,Geriatric Research Education and Clinical Center, Bedford VA Healthcare System, Bedford, MA, USA
| | - Byron J Aguilar
- Geriatric Research Education and Clinical Center, Bedford VA Healthcare System, Bedford, MA, USA.,Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
| | - Dan Berlowitz
- Department of Public Health, Zuckerberg College of Health Sciences, University of Massachusetts Lowell, Lowell, MA, USA
| | - Amir Abbas Tahami Monfared
- Alzheimer's Disease Franchise, Eisai Inc., Nutley, NJ, USA.,Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC, Canada
| | | | - Quanwu Zhang
- Alzheimer's Disease Franchise, Eisai Inc., Nutley, NJ, USA
| | - Weiming Xia
- Geriatric Research Education and Clinical Center, Bedford VA Healthcare System, Bedford, MA, USA. .,Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA.
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Hampel H, Vassar R, De Strooper B, Hardy J, Willem M, Singh N, Zhou J, Yan R, Vanmechelen E, De Vos A, Nisticò R, Corbo M, Imbimbo BP, Streffer J, Voytyuk I, Timmers M, Monfared AAT, Irizarry M, Albala B, Koyama A, Watanabe N, Kimura T, Yarenis L, Lista S, Kramer L, Vergallo A. The β-Secretase BACE1 in Alzheimer's Disease. Biol Psychiatry 2021; 89:745-756. [PMID: 32223911 PMCID: PMC7533042 DOI: 10.1016/j.biopsych.2020.02.001] [Citation(s) in RCA: 277] [Impact Index Per Article: 92.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 01/29/2020] [Accepted: 02/05/2020] [Indexed: 01/18/2023]
Abstract
BACE1 (beta-site amyloid precursor protein cleaving enzyme 1) was initially cloned and characterized in 1999. It is required for the generation of all monomeric forms of amyloid-β (Aβ), including Aβ42, which aggregates into bioactive conformational species and likely initiates toxicity in Alzheimer's disease (AD). BACE1 concentrations and rates of activity are increased in AD brains and body fluids, thereby supporting the hypothesis that BACE1 plays a critical role in AD pathophysiology. Therefore, BACE1 is a prime drug target for slowing down Aβ production in early AD. Besides the amyloidogenic pathway, BACE1 has other substrates that may be important for synaptic plasticity and synaptic homeostasis. Indeed, germline and adult conditional BACE1 knockout mice display complex neurological phenotypes. Despite BACE1 inhibitor clinical trials conducted so far being discontinued for futility or safety reasons, BACE1 remains a well-validated therapeutic target for AD. A safe and efficacious compound with high substrate selectivity as well as a more accurate dose regimen, patient population, and disease stage may yet be found. Further research should focus on the role of Aβ and BACE1 in physiological processes and key pathophysiological mechanisms of AD. The functions of BACE1 and the homologue BACE2, as well as the biology of Aβ in neurons and glia, deserve further investigation. Cellular and molecular studies of BACE1 and BACE2 knockout mice coupled with biomarker-based human research will help elucidate the biological functions of these important enzymes and identify their substrates and downstream effects. Such studies will have critical implications for BACE1 inhibition as a therapeutic approach for AD.
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Affiliation(s)
- Harald Hampel
- Neurology Business Group, Eisai Inc., Woodcliff Lake, New Jersey; Sorbonne University, GRC No. 21, Alzheimer Precision Medicine, Pitié-Salpêtrière Hospital, Paris, France.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Andrea Vergallo
- Neurology Business Group, Eisai Inc., Woodcliff Lake, New Jersey; Sorbonne University, GRC No. 21, Alzheimer Precision Medicine, Pitié-Salpêtrière Hospital, Paris, France; Institute of Memory and Alzheimer's Disease, Department of Neurology, Pitié-Salpêtrière Hospital, Paris, France; Brain & Spine Institute, INSERM U 1127, CNRS UMR 7225, Paris, France.
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Goldman JG, Forsberg LK, Boeve BF, Armstrong MJ, Irwin DJ, Ferman TJ, Galasko D, Galvin JE, Kaufer D, Leverenz J, Lippa CF, Marder K, Abler V, Biglan K, Irizarry M, Keller B, Munsie L, Nakagawa M, Taylor A, Graham T. Challenges and opportunities for improving the landscape for Lewy body dementia clinical trials. Alzheimers Res Ther 2020; 12:137. [PMID: 33121510 PMCID: PMC7597002 DOI: 10.1186/s13195-020-00703-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 10/08/2020] [Indexed: 01/05/2023]
Abstract
Lewy body dementia (LBD), including dementia with Lewy bodies and Parkinson's disease dementia, affects over a million people in the USA and has a substantial impact on patients, caregivers, and society. Symptomatic treatments for LBD, which can include cognitive, neuropsychiatric, autonomic, sleep, and motor features, are limited with only two drugs (cholinesterase inhibitors) currently approved by regulatory agencies for dementia in LBD. Clinical trials represent a top research priority, but there are many challenges in the development and implementation of trials in LBD. To address these issues and advance the field of clinical trials in the LBDs, the Lewy Body Dementia Association formed an Industry Advisory Council (LBDA IAC), in addition to its Research Center of Excellence program. The LBDA IAC comprises a diverse and collaborative group of experts from academic medical centers, pharmaceutical industries, and the patient advocacy foundation. The inaugural LBDA IAC meeting, held in June 2019, aimed to bring together this group, along with representatives from regulatory agencies, to address the topic of optimizing the landscape of LBD clinical trials. This review highlights the formation of the LBDA IAC, current state of LBD clinical trials, and challenges and opportunities in the field regarding trial design, study populations, diagnostic criteria, and biomarker utilization. Current gaps include a lack of standardized clinical assessment tools and evidence-based management strategies for LBD as well as difficulty and controversy in diagnosing LBD. Challenges in LBD clinical trials include the heterogeneity of LBD pathology and symptomatology, limited understanding of the trajectory of LBD cognitive and core features, absence of LBD-specific outcome measures, and lack of established standardized biologic, imaging, or genetic biomarkers that may inform study design. Demands of study participation (e.g., travel, duration, and frequency of study visits) may also pose challenges and impact trial enrollment, retention, and outcomes. There are opportunities to improve the landscape of LBD clinical trials by harmonizing clinical assessments and biomarkers across cohorts and research studies, developing and validating outcome measures in LBD, engaging the patient community to assess research needs and priorities, and incorporating biomarker and genotype profiling in study design.
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Affiliation(s)
- Jennifer G Goldman
- Parkinson's Disease and Movement Disorders Program, Shirley Ryan AbilityLab and Departments of Physical Medicine and Rehabilitation and Neurology, Northwestern University Feinberg School of Medicine, 355 E. Erie Street, Chicago, IL, 60611, USA.
| | | | | | - Melissa J Armstrong
- Department of Neurology, University of Florida College of Medicine, Gainesville, FL, USA
| | - David J Irwin
- Department of Neurology, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Tanis J Ferman
- Department of Psychiatry and Psychology, Mayo Clinic, Jacksonville, FL, USA
| | - Doug Galasko
- Department of Neurosciences, UC San Diego, San Diego, CA, USA
| | - James E Galvin
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Daniel Kaufer
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
| | - James Leverenz
- Lou Ruvo Center for Brain Health, Neurological Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Carol F Lippa
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Karen Marder
- Department of Neurology, Taub Institute, Sergievsky Center, Columbia University Irving Medical Center, New York, NY, USA
| | | | - Kevin Biglan
- Neuroscience Research, Eli Lilly and Company, Indianapolis, IN, USA
| | | | | | - Leanne Munsie
- Neuroscience Research, Eli Lilly and Company, Indianapolis, IN, USA
| | | | - Angela Taylor
- Lewy Body Dementia Association, S.W., Lilburn, GA, USA
| | - Todd Graham
- Lewy Body Dementia Association, S.W., Lilburn, GA, USA
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Messner DA, Rabins P, Downing AC, Irizarry M, Foster NL, Al Naber J, Dabbous O, Fillit H, Gabler S, Krakauer R, Lotz D, Payzant E, Schneider L, Tyrone J, Van Amerongen D, Wuest D. Designing Trials of Disease Modifying Agents for Early and Preclinical Alzheimer's Disease Intervention: What Evidence is Meaningful to Patients, Providers, and Payers? J Prev Alzheimers Dis 2018; 6:20-26. [PMID: 30569082 DOI: 10.14283/jpad.2018.42] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Drug development for disease modifying agents in Alzheimer's disease (AD) is focused increasingly on targeting underlying pathology in very early stages of AD or in cognitively normal patients at elevated risk of developing dementia due to Alzheimer's. Very early interventional studies of this type have many uncertainties, including whether they can provide the clinical results that payers, providers, and patients will wish to see for decisions. This paper describes an initiative to create greater transparency for researchers to anticipate these decision needs. OBJECTIVE To create multi-stakeholder-vetted recommendations for the design of studies in later phases of drug development to evaluate the ability of disease modifying agents to delay or prevent the onset of dementia due to Alzheimer's disease (AD). DESIGN A multi-stakeholder expert workgroup and overseeing steering group were convened to discuss current advances in early interventional clinical trial design and the evidence needs of patients, providers, and payers. Eight teleconferences and one in-person all-day meeting were held. Meetings were recorded and summary notes prepared between sessions. Final conclusions were consolidated by the project team with the workgroup Chair based on these discussions and were reviewed by group members. SETTING The in-person meeting was held in Baltimore, MD. PARTICIPANTS In total, 36 stakeholders representing life sciences industry, payers or health technology assessors, patient advocates and research advocacy organizations, regulators, clinical experts and academic or NIH researchers. INTERVENTION N/A. MEASUREMENTS N/A. RESULTS Certain aspects of clinical trial design were deemed important to address stakeholder decision needs for future Alzheimer's prevention drugs even as the field rapidly progresses. These include the need for more robust behavioral and psychological outcome data in early symptomatic disease and the need to update activities of daily living measures to include "digital independence." CONCLUSIONS Amyloid, tau, and biomarkers of neurodegeneration should be included in trials and studied in relation to other early measures of change meaningful to individuals with AD, their families, and health plans. These measures include early sensitive changes in behavioral and psychological measures and ability to navigate the contemporary digital landscape. Additional work is needed to generate more robust behavioral and psychological outcome data in early symptomatic disease, and to generate multi-stakeholder consensus on early measures of change and magnitudes of change that will be meaningful to patients, providers, and payers.
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Affiliation(s)
- D A Messner
- Donna A. Messner, PhD, Center for Medical Technology Policy, 401 E. Pratt Street, Suite 631, Baltimore, MD 21202, Tel: 410.547.2686 x101, Fax: 410.547.5088,
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Abstract
Dementia with Lewy bodies (DLB) is an increasingly recognized entity which overlaps in clinical, pathological and genetic features with Alzheimer's (AD) and Parkinson's disease (PD). Clinically, it is characterized by progressive cognitive impairment with significant fluctuations in alertness, parkinsonism, and psychosis with recurrent hallucinations. The neuropathological hallmarks are the intracytoplasmic inclusions in substantia nigra typical of PD, known as Lewy bodies (LB), but widely distributed throughout paralimbic and neocortical regions. Most of the cases also coexist with a plaque predominant AD. The evidence of alpha-synuclein in LB and related neurites as well as of a synuclein fragment in AD plaques opens new links among these neurodegenerative diseases. This article will review briefly the clinical and pathologicalfeatures that DLB shares with AD and PD, as well as those that support the idea that it is a distinct disorder.
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Affiliation(s)
| | | | | | - Bradley T. Hyman
- Alzheimer's Disease Research Unit, Massachusetts General Hospital East, Charlestown, Massachusetts
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Gungabissoon U, Hacquoil K, Bains C, Irizarry M, Dukes G, Williamson R, Deane AM, Heyland DK. Prevalence, risk factors, clinical consequences, and treatment of enteral feed intolerance during critical illness. JPEN J Parenter Enteral Nutr 2014; 39:441-8. [PMID: 24637246 DOI: 10.1177/0148607114526450] [Citation(s) in RCA: 141] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 02/11/2014] [Indexed: 12/27/2022]
Abstract
BACKGROUND We aimed to determine the incidence of enteral feed intolerance and factors associated with intolerance and to assess the influence of intolerance on nutrition and clinical outcomes. METHODS We conducted a retrospective analysis of data from an international observational cohort study of nutrition practices among 167 intensive care units (ICUs). Data were collected on nutrition adequacy, ventilator-free days (VFDs), ICU stay, and 60-day mortality. Intolerance was defined as interruption of enteral nutrition (EN) due to gastrointestinal (GI) reasons (large gastric residuals, abdominal distension, emesis, diarrhea, or subjective discomfort). Logistic regression was used to determine risk factors for intolerance and their clinical significance. A sensitivity analysis restricted to sites specifying a gastric residual volume ≥200 mL to identify intolerance was also conducted. RESULTS Data from 1,888 ICU patients were included. The incidence of intolerance was 30.5% and occurred after a median 3 days from EN initiation. Patients remained intolerant for a mean (±SD) duration of 1.9 ± 1.3 days . Intolerance was associated with worse nutrition adequacy vs the tolerant (56% vs 64%, P < .0001), fewer VFDs (2.5 vs 11.2, P < .0001), increased ICU stay (14.4 vs 11.3 days, P < .0001), and increased mortality (30.8% vs 26.2, P = .04). The sensitivity analysis demonstrated that intolerance remained associated with negative outcomes. Although mortality was greater among the intolerant patients, this was not statistically significant. CONCLUSIONS Intolerance occurs frequently during EN in critically ill patients and is associated with poorer nutrition and clinical outcomes.
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Affiliation(s)
- Usha Gungabissoon
- Worldwide Epidemiology, Quantitative Sciences, GlaxoSmithKline R&D, Uxbridge, United Kingdom
| | - Kimberley Hacquoil
- Discovery Biometrics, Quantitative Sciences, GlaxoSmithKline R&D, Uxbridge, United Kingdom
| | - Chanchal Bains
- Worldwide Epidemiology, Quantitative Sciences, GlaxoSmithKline R&D, Uxbridge, United Kingdom
| | - Michael Irizarry
- Worldwide Epidemiology, Quantitative Sciences, GlaxoSmithKline R&D, Durham, North Carolina, USA
| | - George Dukes
- Academic DPU, GlaxoSmithKline R&D, Durham, North Carolina, USA
| | | | - Adam M Deane
- Department of Critical Care Services, Royal Adelaide Hospital and the Discipline of Acute Care Medicine, University of Adelaide, Adelaide, Australia
| | - Daren K Heyland
- Department of Medicine and Public Health Sciences, Queen's University, Kingston, Ontario, Canada Clinical Evaluation Research Unit at Kingston General Hospital, Kingston, Ontario, Canada
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Tomson T, Hirsch LJ, Friedman D, Bester N, Hammer A, Irizarry M, Ishihara L, Krishen A, Spaulding T, Wamil A, Leadbetter R. Sudden unexpected death in epilepsy in lamotrigine randomized-controlled trials. Epilepsia 2012; 54:135-40. [PMID: 23030403 DOI: 10.1111/j.1528-1167.2012.03689.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE Nonrandomized studies of the relationship of antiepileptic drugs (AEDs) with sudden unexpected death in epilepsy (SUDEP) may be susceptible to confounding by tonic-clonic seizure frequency, polypharmacy, and other potential risk factors for SUDEP. We evaluated the risk of SUDEP with lamotrigine (LTG) compared to active comparators and placebo in randomized controlled clinical trials conducted by GlaxoSmithKline (GSK) between 1984 and 2009. METHODS Among 7,774 subjects in 42 randomized clinical trials, there were 39 all-cause deaths. Ten deaths occurred >2 weeks after discontinuation of study medication and were excluded. Narrative summaries of deaths were independently reviewed by three clinical experts (TT, LH, DF), who were blinded to randomized treatment arm. The risk of definite or probable SUDEP was compared between treatment arms for each trial type (placebo-controlled, active-comparator, crossover), using exact statistical methods. KEY FINDINGS Of 29 on-treatment deaths, eight were definite/probable SUDEP, four were possible SUDEP, and 17 were non-SUDEP. The overall, unadjusted rate of definite/probable SUDEP for LTG was 2.2 events per 1,000-patient years (95% confidence interval [95% CI] 0.70-5.4). The odds ratios (OR) for on-treatment, definite/probable SUDEP in LTG arms relative to comparator arms, adjusted for length of exposure and trial, were the following: placebo-controlled, OR 0.22 (95% CI 0.00-3.14; p = 0.26); active-comparator, OR 2.18 (95% CI 0.17-117; p = 0.89); and placebo-controlled cross-over, OR 1.08 (95% CI 0.00-42.2; p = 1.0). SIGNIFICANCE There was no statistically significant difference in rate of SUDEP between LTG and comparator groups. However, the CIs were wide and a clinically important effect cannot be excluded.
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Affiliation(s)
- Torbjörn Tomson
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
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Gungabissoon U, Hacquoil K, Bains C, Dukes G, Irizarry M, Heyland D. Frequency, determinants and impact of feed intolerance amongst the critically ill. Crit Care 2012. [PMCID: PMC3363579 DOI: 10.1186/cc10768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Harrington C, Sawchak S, Chiang C, Davies J, Donovan C, Saunders AM, Irizarry M, Jeter B, Zvartau-Hind M, van Dyck CH, Gold M. Rosiglitazone does not improve cognition or global function when used as adjunctive therapy to AChE inhibitors in mild-to-moderate Alzheimer's disease: two phase 3 studies. Curr Alzheimer Res 2011; 8:592-606. [PMID: 21592048 DOI: 10.2174/156720511796391935] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Accepted: 01/30/2011] [Indexed: 11/22/2022]
Abstract
INTRODUCTION Two phase 3 studies evaluated the efficacy and safety of rosiglitazone (RSG), a type 2 diabetes treatment, in an extended release (RSG XR) form as adjunctive therapy to ongoing acetylcholine esterase inhibitor (AChEI) treatment in AD (REFLECT-2, adjunctive to donepezil; REFLECT-3, to any AChEI). An open-label extension study (REFLECT-4) assessed RSG XR long-term safety. METHODS In these two double-blind, placebo-controlled studies, subjects with mild-to-moderate probable AD were randomized within 2 apolipoprotein E (APOE) allelic strata (APOE ε4-positive, APOE ε4-negative) to once daily placebo, 2 mg RSG XR, or 8 mg RSG XR for 48 weeks (REFLECT-2, N=1,496; REFLECT-3, N=1,485). Co-primary efficacy endpoints were change from baseline in Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) and Clinical Dementia Rating scale - Sum of Boxes (CDR-SB) scores at week 48. Three populations were analyzed: APOE4-negative, all subjects except APOE ε4 homozygotes, and the full intent-to-treat population. RESULTS No statistically or clinically relevant differences between treatment groups were observed on the a priori primary endpoints in REFLECT-2 or REFLECT-3. Edema was the most frequent adverse event with RSG in each study (14% and 19%, respectively, at 8 mg RSG XR). CONCLUSIONS No evidence of statistically or clinically significant efficacy in cognition or global function was detected for 2 mg or 8 mg RSG XR as adjunctive therapy to ongoing AChEIs. There was no evidence of an interaction between treatment and APOE status. Safety and tolerability of RSG XR was consistent with the known profile of rosiglitazone.
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Affiliation(s)
- C Harrington
- Neurosciences Medicines Development Center, GlaxoSmithKline, Research Triangle Park, NC, USA.
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Fitzpatrick A, Irizarry M, Cushman M, Jenny N, Chi G, Koro C. O2‐04‐05: Lipoprotein‐associated phospholipase A2 (Lp‐PLA2) and risk of dementia in the cardiovascular health study. Alzheimers Dement 2011. [DOI: 10.1016/j.jalz.2011.05.862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
| | | | - Mary Cushman
- University of Vermont College of MedicineBurlingtonVermontUnited States
| | - Nancy Jenny
- University of Vermont College of MedicineBurlingtonVermontUnited States
| | - Gloria Chi
- University of WashingtonSeattleWash.United States
| | - Carol Koro
- GalaxoSmithKlineResearch Triangle ParkN.C.United States
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Gold M, Alderton C, Zvartau-Hind M, Egginton S, Saunders AM, Irizarry M, Craft S, Landreth G, Linnamägi Ü, Sawchak S. Rosiglitazone monotherapy in mild-to-moderate Alzheimer's disease: results from a randomized, double-blind, placebo-controlled phase III study. Dement Geriatr Cogn Disord 2010; 30:131-46. [PMID: 20733306 PMCID: PMC3214882 DOI: 10.1159/000318845] [Citation(s) in RCA: 245] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/21/2010] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND/AIMS A phase II study of the peroxisome proliferator-activated receptor-γ agonist rosiglitazone extended release (RSG XR) in mild-to-moderate Alzheimer's disease (AD) detected a treatment benefit to cognition in apolipoprotein E(APOE)-ε4-negative subjects. The current phase III study with prospective stratification by APOE genotype was conducted to confirm the efficacy and safety of RSG XR in mild-to-moderate AD. An open-label extension study assessed the long-term safety and tolerability of 8 mg RSG XR. METHODS This double-blind, randomized, placebo-controlled study enrolled 693 subjects. Within 2 APOE allelic strata (ε4-positive, ε4-negative), subjects were randomized (2:2:2:1) to once-daily placebo, 2 mg RSG XR, 8 mg RSG XR or 10 mg donepezil (control). Coprimary endpoints were change from baseline to week 24 in the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-Cog) score, and week 24 Clinician's Interview-Based Impression of Change plus caregiver input (CIBIC+). RESULTS At week 24, no significant differences from placebo in change from baseline in coprimary endpoints were detected with either the RSG XR dose in APOE-ε4-negative subjects or overall. For donepezil, no significant treatment difference was detected in ADAS-Cog; however, a significant difference was detected (p = 0.009) on the CIBIC+. Peripheral edema was the most common adverse event for 8 mg RSG XR (15%) and placebo (5%), and nasopharyngitis for 2 mg RSG XR (7%). CONCLUSION No evidence of efficacy of 2 mg or 8 mg RSG XR monotherapy in cognition or global function was detected in the APOE-ε4-negative or other analysis populations. The safety and tolerability of RSG XR was consistent with its known pharmacology.
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Affiliation(s)
- Michael Gold
- Neurosciences Medicines Development Center, GlaxoSmithKline, Stockley Park, Harlow, UK.
| | - Claire Alderton
- Neurosciences Medicines Development Center, GlaxoSmithKline, Stockley Park, UK
| | - Marina Zvartau-Hind
- Neurosciences Medicines Development Center, GlaxoSmithKline, Stockley Park, UK
| | - Sally Egginton
- Neurosciences Medicines Development Center, GlaxoSmithKline, Harlow, UK
| | - Ann M. Saunders
- Deane Drug Discovery Institute, Division of Neurology, Duke University Medical Center, Durham, N.C., USA
| | - Michael Irizarry
- Neurosciences Medicines Development Center, GlaxoSmithKline, Research Triangle Park, N.C., USA
| | - Suzanne Craft
- Geriatric Research, Education and Clinical Center, VA Puget Sound Health Care System and Department of Psychiatry and Behavioral Sciences, University of Washington School of Medicine, Seattle, Wash., USA
| | - Gary Landreth
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA
| | - Ülla Linnamägi
- Department of Neurology and Neurosurgery, University of Tartu, Tartu, Estonia
| | - Sharon Sawchak
- Neurosciences Medicines Development Center, GlaxoSmithKline, Research Triangle Park, N.C., USA
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Ishihara L, Webb DJ, Irizarry M, Weil J. Exploring differential prescribing between anti-epileptic drugs in epilepsy patients with a history of mood disorders. Pharmacoepidemiol Drug Saf 2010; 19:289-95. [DOI: 10.1002/pds.1905] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Harrington C, Sawchak S, Chiang C, Davies J, Saunders A, Irizarry M, Zvartau‐Hind M, Dyck C, Gold M. P4‐299: Effects Of Rosiglitazone‐extended Release As Adjunctive Therapy To Acetylcholinesterase Inhibitors Over 48 Weeks On Cognition In
Apoe4
‐stratified Subjects With Mild‐to‐moderate Alzheimer's Disease. Alzheimers Dement 2009. [DOI: 10.1016/j.jalz.2009.07.079] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Steinerman JR, Irizarry M, Scarmeas N, Raju S, Brandt J, Albert M, Blacker D, Hyman B, Stern Y. Distinct pools of beta-amyloid in Alzheimer disease-affected brain: a clinicopathologic study. ACTA ACUST UNITED AC 2008; 65:906-12. [PMID: 18625856 DOI: 10.1001/archneur.65.7.906] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To determine whether beta-amyloid (Abeta) peptides segregated into distinct biochemical compartments would differentially correlate with clinical severity of Alzheimer disease (AD). DESIGN Clinicopathologic correlation study. PARTICIPANTS Twenty-seven patients from a longitudinal study of AD and 13 age- and sex-matched controls without a known history of cognitive impairment or dementia were included in this study. INTERVENTIONS Temporal and cingulate neocortex were processed using a 4-step extraction, yielding biochemical fractions that are hypothesized to be enriched with proteins from distinct anatomical compartments: TRIS (extracellular soluble), Triton (intracellular soluble), sodium dodecyl sulfate (SDS) (membrane associated), and formic acid (extracellular insoluble). Levels of Abeta(40) and Abeta(42) were quantified in each biochemical compartment by enzyme-linked immunosorbent assay. RESULTS The Abeta(42) level in all biochemical compartments was significantly elevated in patients with AD vs controls (P < .01). The Abeta(40) levels in the TRIS and formic acid fractions were elevated in patients with AD (temporal, P < .01; cingulate, P = .03); however, Triton and SDS Abeta(40) levels were similar in patients with AD and in controls. Functional impairment proximal to death correlated with Triton Abeta(42) (r = 0.48, P = .02) and SDS Abeta(42) (r = 0.41, P = .04) in the temporal cortex. Faster cognitive decline was associated with elevated temporal SDS Abeta(42) levels (P < .001), whereas slower decline was associated with elevated cingulate formic acid Abeta(42) and SDS Abeta(42) levels (P = .02 and P = .01, respectively). CONCLUSION Intracellular and membrane-associated Abeta, especially Abeta(42) in the temporal neocortex, may be more closely related to AD symptoms than other measured Abeta species.
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Affiliation(s)
- Joshua R Steinerman
- Departments of Neurology, Columbia University Medical Center, 630 W 168th St, P&S Box 16, New York, NY 10032, USA
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Lleó A, Berezovska O, Herl L, Raju S, Deng A, Bacskai BJ, Frosch MP, Irizarry M, Hyman BT. Nonsteroidal anti-inflammatory drugs lower Abeta42 and change presenilin 1 conformation. Nat Med 2004; 10:1065-6. [PMID: 15448688 DOI: 10.1038/nm1112] [Citation(s) in RCA: 168] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2004] [Accepted: 09/07/2004] [Indexed: 11/09/2022]
Abstract
Recent reports suggest that some commonly used nonsteroidal anti-inflammatory drugs (NSAIDs) unexpectedly shift the cleavage products of amyloid precursor protein (APP) to shorter, less fibrillogenic forms, although the underlying mechanism remains unknown. We now demonstrate, using a fluorescence resonance energy transfer method, that Abeta(42)-lowering NSAIDs specifically affect the proximity between APP and presenilin 1 and alter presenilin 1 conformation both in vitro and in vivo, suggesting a novel allosteric mechanism of action.
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Affiliation(s)
- Alberto Lleó
- Alzheimer Research Unit, Massachusetts General Hospital, 114 16th St, Charlestown, Massachusetts 02129, USA
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Lleo A, Berezovska O, Herl L, Raju S, Deng A, Irizarry M, Hyman BT. P4-324 Nonsteroidal anti-inflammatory drugs (NSAIDS) lower Aβ42 and change presenilin1 confomation. Neurobiol Aging 2004. [DOI: 10.1016/s0197-4580(04)81882-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Wexler NS, Lorimer J, Porter J, Gomez F, Moskowitz C, Shackell E, Marder K, Penchaszadeh G, Roberts SA, Gayán J, Brocklebank D, Cherny SS, Cardon LR, Gray J, Dlouhy SR, Wiktorski S, Hodes ME, Conneally PM, Penney JB, Gusella J, Cha JH, Irizarry M, Rosas D, Hersch S, Hollingsworth Z, MacDonald M, Young AB, Andresen JM, Housman DE, De Young MM, Bonilla E, Stillings T, Negrette A, Snodgrass SR, Martinez-Jaurrieta MD, Ramos-Arroyo MA, Bickham J, Ramos JS, Marshall F, Shoulson I, Rey GJ, Feigin A, Arnheim N, Acevedo-Cruz A, Acosta L, Alvir J, Fischbeck K, Thompson LM, Young A, Dure L, O'Brien CJ, Paulsen J, Brickman A, Krch D, Peery S, Hogarth P, Higgins DS, Landwehrmeyer B. Venezuelan kindreds reveal that genetic and environmental factors modulate Huntington's disease age of onset. Proc Natl Acad Sci U S A 2004; 101:3498-503. [PMID: 14993615 PMCID: PMC373491 DOI: 10.1073/pnas.0308679101] [Citation(s) in RCA: 499] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Huntington's disease (HD) is an autosomal dominant neurodegenerative disease caused by a triplet (CAG) expansion mutation. The length of the triplet repeat is the most important factor in determining age of onset of HD, although substantial variability remains after controlling for repeat length. The Venezuelan HD kindreds encompass 18,149 individuals spanning 10 generations, 15,409 of whom are living. Of the 4,384 immortalized lymphocyte lines collected, 3,989 DNAs were genotyped for their HD alleles, representing a subset of the population at greatest genetic risk. There are 938 heterozygotes, 80 people with variably penetrant alleles, and 18 homozygotes. Analysis of the 83 kindreds that comprise the Venezuelan HD kindreds demonstrates that residual variability in age of onset has both genetic and environmental components. We created a residual age of onset phenotype from a regression analysis of the log of age of onset on repeat length. Familial correlations (correlation +/- SE) were estimated for sibling (0.40 +/- 0.09), parent-offspring (0.10 +/- 0.11), avuncular (0.07 +/- 0.11), and cousin (0.15 +/- 0.10) pairs, suggesting a familial origin for the residual variance in onset. By using a variance-components approach with all available familial relationships, the additive genetic heritability of this residual age of onset trait is 38%. A model, including shared sibling environmental effects, estimated the components of additive genetic (0.37), shared environment (0.22), and nonshared environment (0.41) variances, confirming that approximately 40% of the variance remaining in onset age is attributable to genes other than the HD gene and 60% is environmental.
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Affiliation(s)
- Nancy S Wexler
- Columbia University, 1051 Riverside Drive, New York, NY 10032, USA.
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Spittaels K, Van den Haute C, Van Dorpe J, Terwel D, Vandezande K, Lasrado R, Bruynseels K, Irizarry M, Verhoye M, Van Lint J, Vandenheede JR, Ashton D, Mercken M, Loos R, Hyman B, Van der Linden A, Geerts H, Van Leuven F. Neonatal neuronal overexpression of glycogen synthase kinase-3 beta reduces brain size in transgenic mice. Neuroscience 2002; 113:797-808. [PMID: 12182887 DOI: 10.1016/s0306-4522(02)00236-1] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Glycogen synthase kinase-3beta (GSK-3beta) is important in neurogenesis. Here we demonstrate that the kinase influenced post-natal maturation and differentiation of neurons in vivo in transgenic mice that overexpress a constitutively active GSK-3beta[S9A]. Magnetic resonance imaging revealed a reduced volume of the entire brain, concordant with a nearly 20% reduction in wet brain weight. The reduced volume was most prominent for the cerebral cortex, without however, disturbing the normal cortical layering. The resulting compacted architecture was further demonstrated by an increased neuronal density, by reduced size of neuronal cell bodies and of the somatodendritic compartment of pyramidal neurons in the cortex. No evidence for apoptosis was obtained. The marked overall reduction in the level of the microtubule-associated protein 2 in brain and in spinal cord, did not affect the ultrastructure of the microtubular cytoskeleton in the proximal apical dendrites. The overall reduction in size of the entire CNS induced by constitutive active GSK-3beta caused only very subtle changes in the psychomotoric ability of adult and ageing GSK-3beta transgenic mice.
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Affiliation(s)
- K Spittaels
- Experimental Genetics Group, Department of Human Genetics, KU Leuven, Campus Gasthuisberg O&N 06, B-3000 Leuven, Belgium
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Chapman PF, White GL, Jones MW, Cooper-Blacketer D, Marshall VJ, Irizarry M, Younkin L, Good MA, Bliss TV, Hyman BT, Younkin SG, Hsiao KK. Impaired synaptic plasticity and learning in aged amyloid precursor protein transgenic mice. Nat Neurosci 1999; 2:271-6. [PMID: 10195221 DOI: 10.1038/6374] [Citation(s) in RCA: 683] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We investigated synaptic communication and plasticity in hippocampal slices from mice overexpressing mutated 695-amino-acid human amyloid precursor protein (APP695SWE), which show behavioral and histopathological abnormalities simulating Alzheimer's disease. Although aged APP transgenic mice exhibit normal fast synaptic transmission and short term plasticity, they are severely impaired in in-vitro and in-vivo long-term potentiation (LTP) in both the CA1 and dentate gyrus regions of the hippocampus. The LTP deficit was correlated with impaired performance in a spatial working memory task in aged transgenics. These deficits are accompanied by minimal or no loss of presynaptic or postsynaptic elementary structural elements in the hippocampus, suggesting that impairments in functional synaptic plasticity may underlie some of the cognitive deficits in these mice and, possibly, in Alzheimer's patients.
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Affiliation(s)
- P F Chapman
- Cardiff School of Biosciences, Cardiff University, Wales, UK
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Roots R, Holley W, Chatterjee A, Irizarry M, Kraft G. The formation of strand breaks in DNA after high-LET irradiation: a comparison of data from in vitro and cellular systems. Int J Radiat Biol 1990; 58:55-69. [PMID: 1973440 DOI: 10.1080/09553009014551431] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
This paper presents a summary of our understanding to date of the formation of DNA strand breaks induced by highly energetic particle beams (high-LET radiation). We have compared our own recent data on the formation of strand breaks induced in DNA in an aqueous solution with our previous data and those of others available from the literature for similar lesions made in cellular DNA. When the strand break induction frequency, as number of breaks per Gy per unit DNA, is plotted against LET, a series of biological effect curves (one for each particle atomic number Z) is obtained. The frequency of the formation of single-strand breaks has an RBE of less than 1 for DNA in solution and for DNA in the cell; the frequency of the formation of double-strand breaks (dsb) also has an RBE of less than 1 for DNA in a solution containing low amounts of free radical scavenger(s), while the RBE can be greater than 1 in the 50-200 keV/microns range for cellular DNA. RBE values are with respect to X-rays or cobalt gamma-rays. In cells the level of unrejoined strand breaks is also highest in the 50-200 keV/microns range and may reach 25-35% of the initial break yield depending on particle energy and Z-value. These irreparable lesions include double-strand scissions and some form(s) of single-strand breaks. The data presented cover results obtained for helium to uranium particles, with an LET range of 16 to 160,000 keV/microns. When different biological end-points are compared a strong correlation is found between induction of dsb, chromosomal abnormalities and mutation induction.
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Affiliation(s)
- R Roots
- Cellular and Molecular Biology Division, Lawrence Berkeley Laboratory, University of California, Berkeley 94720
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