Browsing by Author "Mackenzie, Ian R."

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    Aging-related tau astrogliopathy (ARTAG): harmonized evaluation strategy
    (Springer, 2016-01) Kovacs, Gabor G.; Ferrer, Isidro; Alafuzoff, Irina; Attems, Johannes; Budka, Herbert; Cairns, Nigel J.; Crary, John F.; Duyckaerts, Charles; Ghetti, Bernardino; Halliday, Glenda M.; Ironside, James W.; Love, Seth; Mackenzie, Ian R.; Munoz, David G.; Murray, Melissa E.; Nelson, Peter T.; Takahashi, Hitoshi; Trojanowski, John Q.; Ansorge, Olaf; Arzberger, Thomas; Baborie, Atik; Beach, Thomas G.; Bieniek, Kevin F.; Bigio, Eileen H.; Bodi, Istvan; Dugger, Brittany N.; Feany, Mel; Gelpi, Ellen; Gentleman, Stephen M.; Giaccone, Giorgio; Hatanpaa, Kimmo J.; Heale, Richard; Hof, Patrick R.; Hofer, Monika; Hortobágyi, Tibor; Jellinger, Kurt; Jicha, Gregory A.; Ince, Paul; Kofler, Julia; Kövari, Enikö; Kril, Jillian J.; Mann, David M.; Matej, Radoslav; McKee, Ann C.; McLean, Catriona; Milenkovic, Ivan; Montine, Thomas J.; Murayama, Shigeo; Lee, Edward B.; Rahimi, Jasmin; Rodriguez, Roberta D.; Rozemüller, Annemieke; Schneider, Julie A.; Schultz, Christian; Seeley, William; Seilhean, Danielle; Smith, Colin; Tagliavini, Fabrizio; Takao, Masaki; Thal, Dietmar Rudolf; Toledo, Jon B.; Tolnay, Markus; Troncoso, Juan C.; Vinters, Harry V.; Weis, Serge; Wharton, Stephen B.; White III, Charles L.; Wisniewski, Thomas; Woulfe, John M.; Yamada, Masahito; Dicks, Dennis W.; Department of Pathology and Laboratory Medicine, IU School of Medicine
    Pathological accumulation of abnormally phosphorylated tau protein in astrocytes is a frequent, but poorly characterized feature of the aging brain. Its etiology is uncertain, but its presence is sufficiently ubiquitous to merit further characterization and classification, which may stimulate clinicopathological studies and research into its pathobiology. This paper aims to harmonize evaluation and nomenclature of aging-related tau astrogliopathy (ARTAG), a term that refers to a morphological spectrum of astroglial pathology detected by tau immunohistochemistry, especially with phosphorylation-dependent and 4R isoform-specific antibodies. ARTAG occurs mainly, but not exclusively, in individuals over 60 years of age. Tau-immunoreactive astrocytes in ARTAG include thorn-shaped astrocytes at the glia limitans and in white matter, as well as solitary or clustered astrocytes with perinuclear cytoplasmic tau immunoreactivity that extends into the astroglial processes as fine fibrillar or granular immunopositivity, typically in gray matter. Various forms of ARTAG may coexist in the same brain and might reflect different pathogenic processes. Based on morphology and anatomical distribution, ARTAG can be distinguished from primary tauopathies, but may be concurrent with primary tauopathies or other disorders. We recommend four steps for evaluation of ARTAG: (1) identification of five types based on the location of either morphologies of tau astrogliopathy: subpial, subependymal, perivascular, white matter, gray matter; (2) documentation of the regional involvement: medial temporal lobe, lobar (frontal, parietal, occipital, lateral temporal), subcortical, brainstem; (3) documentation of the severity of tau astrogliopathy; and (4) description of subregional involvement. Some types of ARTAG may underlie neurological symptoms; however, the clinical significance of ARTAG is currently uncertain and awaits further studies. The goal of this proposal is to raise awareness of astroglial tau pathology in the aged brain, facilitating communication among neuropathologists and researchers, and informing interpretation of clinical biomarkers and imaging studies that focus on tau-related indicators.
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    Comprehensive cross-sectional and longitudinal comparisons of plasma glial fibrillary acidic protein and neurofilament light across FTD spectrum disorders
    (Springer Nature, 2025-03-12) Sheth, Udit; Öijerstedt, Linn; Heckman, Michael G.; White, Launia J.; Heuer, Hilary W.; Lago, Argentina Lario; Forsberg, Leah K.; Faber, Kelley M.; Foroud, Tatiana M.; Rademakers, Rosa; Ramos, Eliana Marisa; Appleby, Brian S.; Bozoki, Andrea C.; Darby, R. Ryan; Dickerson, Bradford C.; Domoto-Reilly, Kimiko; Galasko, Douglas R.; Ghoshal, Nupur; Graff-Radford, Neill R.; Grant, Ian M.; Hales, Chadwick M.; Hsiung, Ging-Yuek Robin; Huey, Edward D.; Irwin, David; Kwan, Justin Y.; Litvan, Irene; Mackenzie, Ian R.; Masdeu, Joseph C.; Mendez, Mario F.; Onyike, Chiadi U.; Pascual, Belen; Pressman, Peter S.; Roberson, Erik D.; Snyder, Allison; Tartaglia, M. Carmela; Seeley, William W.; Dickson, Dennis W.; Rosen, Howard J.; Boeve, Bradley F.; Boxer, Adam L.; Petrucelli, Leonard; Gendron, Tania F.; Medical and Molecular Genetics, School of Medicine
    Background: Therapeutic development for frontotemporal dementia (FTD) is hindered by the lack of biomarkers that inform susceptibility/risk, prognosis, and the underlying causative pathology. Blood glial fibrillary acidic protein (GFAP) has garnered attention as a FTD biomarker. However, investigations of GFAP in FTD have been hampered by symptomatic and histopathologic heterogeneity and small cohort sizes contributing to inconsistent findings. Therefore, we evaluated plasma GFAP as a FTD biomarker and compared its performance to that of neurofilament light (NfL) protein, a leading FTD biomarker. Methods: We availed ARTFL LEFFTDS Longitudinal Frontotemporal Lobar Degeneration (ALLFTD) study resources to conduct a comprehensive cross-sectional and longitudinal examination of the susceptibility/risk, prognostic, and predictive performance of GFAP and NfL in the largest series of well-characterized presymptomatic FTD mutation carriers and participants with sporadic or familial FTD syndromes. Utilizing single molecule array technology, we measured GFAP and NfL in plasma from 161 controls, 127 presymptomatic mutation carriers, 702 participants with a FTD syndrome, and 67 participants with mild behavioral and/or cognitive changes. We used multivariable linear regression and Cox proportional hazard models adjusted for co-variates to examine the biomarker utility of baseline GFAP and NfL concentrations or their rates of change. Results: Compared to controls, GFAP and NfL were elevated in each FTD syndrome but GFAP, unlike NfL, poorly discriminated controls from participants with mild symptoms. Similarly, both baseline GFAP and NfL were higher in presymptomatic mutation carriers who later phenoconverted, but NfL better distinguished non-converters from phenoconverters. We additionally observed that GFAP and NfL were associated with disease severity indicators and survival, but NfL far outperformed GFAP. Nevertheless, we validated findings that the GFAP/NfL ratio may discriminate frontotemporal lobar degeneration with tau versus TDP-43 pathology. Conclusions: Our head-to-head comparison of plasma GFAP and NfL as biomarkers for FTD indicate that NfL consistently outmatched GFAP as a prognostic and predictive biomarker for participants with a FTD syndrome, and as a susceptibility/risk biomarker for people at genetic risk of FTD. Our findings underscore the need to include leading biomarkers in investigations evaluating new biomarkers if the field is to fully ascertain their performance and clinical value.
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    Plasma Neurofilament Light for Prediction of Disease Progression in Familial Frontotemporal Lobar Degeneration
    (American Academy of Neurology, 2021-05-04) Rojas, Julio C.; Wang, Ping; Staffaroni, Adam M.; Heller, Carolin; Cobigo, Yann; Wolf, Amy; Goh, Sheng-Yang M.; Ljubenkov, Peter A.; Heuer, Hilary W.; Fong, Jamie C.; Taylor, Joanne B.; Veras, Eliseo; Song, Linan; Jeromin, Andreas; Hanlon, David; Yu, Lili; Khinikar, Arvind; Sivasankaran, Rajeev; Kieloch, Agnieszka; Valentin, Marie-Anne; Karydas, Anna M.; Mitic, Laura L.; Pearlman, Rodney; Kornak, John; Kramer, Joel H.; Miller, Bruce L.; Kantarci, Kejal; Knopman, David S.; Graff-Radford, Neill; Petrucelli, Leonard; Rademakers, Rosa; Irwin, David J.; Grossman, Murray; Ramos, Eliana Marisa; Coppola, Giovanni; Mendez, Mario F.; Bordelon, Yvette; Dickerson, Bradford C.; Ghoshal, Nupur; Huey, Edward D.; Mackenzie, Ian R.; Appleby, Brian S.; Domoto-Reilly, Kimiko; Hsiung, Ging-Yuek R.; Toga, Arthur W.; Weintraub, Sandra; Kaufer, Daniel I.; Kerwin, Diana; Litvan, Irene; Onyike, Chiadikaobi U.; Pantelyat, Alexander; Roberson, Erik D.; Tartaglia, Maria C.; Foroud, Tatiana; Chen, Weiping; Czerkowicz, Julie; Graham, Danielle L.; van Swieten, John C.; Borroni, Barbara; Sanchez-Valle, Raquel; Moreno, Fermin; Laforce, Robert; Graff, Caroline; Synofzik, Matthis; Galimberti, Daniela; Rowe, James B.; James B., Mario; Finger, Elizabeth; Vandenberghe, Rik; de Mendonça, Alexandre; Tagliavini, Fabrizio; Santana, Isabel; Ducharme, Simon; Butler, Chris R.; Gerhard, Alexander; Levin, Johannes; Danek, Adrian; Otto, Markus; Sorbi, Sandro; Cash, David M.; Convery, Rhian S.; Bocchetta, Martina; Foiani, Martha; Greaves, Caroline V.; Peakman, Georgia; Russell, Lucy; Swift, Imogen; Todd, Emily; Rohrer, Jonathan D.; Boeve, Bradley F.; Rosen, Howard J.; Boxer, Adam L.; Neurology, School of Medicine
    Objective: We tested the hypothesis that plasma neurofilament light chain (NfL) identifies asymptomatic carriers of familial frontotemporal lobar degeneration (FTLD)-causing mutations at risk of disease progression. Methods: Baseline plasma NfL concentrations were measured with single-molecule array in original (n = 277) and validation (n = 297) cohorts. C9orf72, GRN, and MAPT mutation carriers and noncarriers from the same families were classified by disease severity (asymptomatic, prodromal, and full phenotype) using the CDR Dementia Staging Instrument plus behavior and language domains from the National Alzheimer's Disease Coordinating Center FTLD module (CDR+NACC-FTLD). Linear mixed-effect models related NfL to clinical variables. Results: In both cohorts, baseline NfL was higher in asymptomatic mutation carriers who showed phenoconversion or disease progression compared to nonprogressors (original: 11.4 ± 7 pg/mL vs 6.7 ± 5 pg/mL, p = 0.002; validation: 14.1 ± 12 pg/mL vs 8.7 ± 6 pg/mL, p = 0.035). Plasma NfL discriminated symptomatic from asymptomatic mutation carriers or those with prodromal disease (original cutoff: 13.6 pg/mL, 87.5% sensitivity, 82.7% specificity; validation cutoff: 19.8 pg/mL, 87.4% sensitivity, 84.3% specificity). Higher baseline NfL correlated with worse longitudinal CDR+NACC-FTLD sum of boxes scores, neuropsychological function, and atrophy, regardless of genotype or disease severity, including asymptomatic mutation carriers. Conclusions: Plasma NfL identifies asymptomatic carriers of FTLD-causing mutations at short-term risk of disease progression and is a potential tool to select participants for prevention clinical trials. Trial registration information: ClinicalTrials.gov Identifier: NCT02372773 and NCT02365922. Classification of evidence: This study provides Class I evidence that in carriers of FTLD-causing mutations, elevation of plasma NfL predicts short-term risk of clinical progression.
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    Proposed research criteria for prodromal behavioural variant frontotemporal dementia
    (Oxford University Press, 2022) Barker, Megan S.; Gottesman, Reena T.; Manoochehri, Masood; Chapman, Silvia; Appleby, Brian S.; Brushaber, Danielle; Devick, Katrina L.; Dickerson, Bradford C.; Domoto-Reilly, Kimiko; Fields, Julie A.; Forsberg, Leah K.; Galasko, Douglas R.; Ghoshal, Nupur; Goldman, Jill; Graff-Radford, Neill R.; Grossman, Murray; Heuer, Hilary W.; Hsiung, Ging-Yuek; Knopman, David S.; Kornak, John; Litvan, Irene; Mackenzie, Ian R.; Masdeu, Joseph C.; Mendez, Mario F.; Pascual, Belen; Staffaroni, Adam M.; Tartaglia, Maria Carmela; Boeve, Bradley F.; Boxer, Adam L.; Rosen, Howard J.; Rankin, Katherine P.; Cosentino, Stephanie; Rascovsky, Katya; Huey, Edward D.; ALLFTD Consortium; Neurology, School of Medicine
    At present, no research criteria exist for the diagnosis of prodromal behavioural variant frontotemporal dementia (bvFTD), though early detection is of high research importance. Thus, we sought to develop and validate a proposed set of research criteria for prodromal bvFTD, termed 'mild behavioural and/or cognitive impairment in bvFTD' (MBCI-FTD). Participants included 72 participants deemed to have prodromal bvFTD; this comprised 55 carriers of a pathogenic mutation known to cause frontotemporal lobar degeneration, and 17 individuals with autopsy-confirmed frontotemporal lobar degeneration. All had mild behavioural and/or cognitive changes, as judged by an evaluating clinician. Based on extensive clinical workup, the prodromal bvFTD group was divided into a Development Group (n = 22) and a Validation Group (n = 50). The Development Group was selected to be the subset of the prodromal bvFTD group for whom we had the strongest longitudinal evidence of conversion to bvFTD, and was used to develop the MBCI-FTD criteria. The Validation Group was the remainder of the prodromal bvFTD group and was used as a separate sample on which to validate the criteria. Familial non-carriers were included as healthy controls (n = 165). The frequencies of behavioural and neuropsychiatric features, neuropsychological deficits, and social cognitive dysfunction in the prodromal bvFTD Development Group and healthy controls were assessed. Based on sensitivity and specificity analyses, seven core features were identified: apathy without moderate-severe dysphoria, behavioural disinhibition, irritability/agitation, reduced empathy/sympathy, repetitive behaviours (simple and/or complex), joviality/gregariousness, and appetite changes/hyperorality. Supportive features include a neuropsychological profile of impaired executive function or naming with intact orientation and visuospatial skills, reduced insight for cognitive or behavioural changes, and poor social cognition. Three core features or two core features plus one supportive feature are required for the diagnosis of possible MBCI-FTD; probable MBCI-FTD requires imaging or biomarker evidence, or a pathogenic genetic mutation. The proposed MBCI-FTD criteria correctly classified 95% of the prodromal bvFTD Development Group, and 74% of the prodromal bvFTD Validation Group, with a false positive rate of <10% in healthy controls. Finally, the MBCI-FTD criteria were tested on a cohort of individuals with prodromal Alzheimer's disease, and the false positive rate of diagnosis was 11-16%. Future research will need to refine the sensitivity and specificity of these criteria, and incorporate emerging biomarker evidence.
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    Psychotropic medication usage in sporadic versus genetic behavioral-variant frontotemporal dementia
    (Wiley, 2025) Vargas-Gonzalez, Juan-Camilo; Dimal, Nico; Cortez, Kasey; Heuer, Hilary; Forsberg, Leah K.; Appleby, Brian S.; Barmada, Sami; Bozoki, Andrea; Clark, David; Cobigo, Yann; Darby, R. Ryan; Dickerson, Bradford C.; Domoto-Reilly, Kimiko; Galasko, Douglas R.; Geschwind, Daniel H.; Ghoshal, Nupur; Graff-Radford, Neill R.; Grant, Ian M.; Irwin, David; Hsiung, Ging-Yuek Robin; Honig, Lawrence S.; Kantarci, Kejal; Léger, Gabriel C.; Litvan, Irene; Mackenzie, Ian R.; Masdeu, Joseph C.; Mendez, Mario F.; Onyike, Chiadi U.; Pascual, Belen; Pressman, Peter; Ramos, Eliana Marisa; Roberson, Erik D.; Rogalski, Emily; Boeve, Brad F.; Boxer, Adam L.; Rosen, Howie J.; Tartaglia, Maria Carmela; ALLFTD Consortium Investigators; Neurology, School of Medicine
    Introduction: Psychotropic medication (PM) use in behavioral-variant frontotemporal dementia (bvFTD) is higher than in other dementias. However, no information exists on whether PM use differs between sporadic and genetic bvFTD. Methods: We analyzed data from sporadic and genetic bvFTD participants with PM prescriptions in the Advancing Research and Treatment in Frontotemporal Lobar Degeneration/Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects study. We estimated ordinal odds ratio (OOR) of having more PM comparing sporadic and genetic bvFTD. Finally, we explored the neuropsychiatric symptom (NPS) combinations using classification and regression trees (CART). Results: We included 263 with sporadic and 193 with genetic bvFTD. The OOR for sporadic bvFTD to be on PM was 1.75 (95% confidence interval: 1.21 to 2.53) for the fully adjusted model. CART revealed the most common NPS combination was apathy + personality changes in 18% of participants. Discussion: Participants with sporadic bvFTD were twice as likely to be on PM compared to genetic bvFTD. The reason for increased PM usage in sporadic bvFTD participants should be further investigated. Highlights: We report on patients with behavioral variant frontotemporal dementia (bvFTD). We evaluated the psychotropic medication (PM) prescription at baseline in the cohort. Patients with sporadic bvFTD had more prescriptions for PM than genetic patients. The frequency of symptoms combination was different in sporadic and genetic bvFTD.
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    Recognition memory and divergent cognitive profiles in prodromal genetic frontotemporal dementia
    (Elsevier, 2021) Barker, Megan S.; Manoochehri, Masood; Rizer, Sandra J.; Appleby, Brian S.; Brushaber, Danielle; Dev, Sheena I.; Devick, Katrina L.; Dickerson, Bradford C.; Fields, Julie A.; Foroud, Tatiana M.; Forsberg, Leah K.; Galasko, Douglas R.; Ghoshal, Nupur; Graff-Radford, Neill R.; Grossman, Murray; Heuer, Hilary W.; Hsiung, Ging-Yuek; Kornak, John; Litvan, Irene; Mackenzie, Ian R.; Mendez, Mario F.; Pascual, Belen; Rankin, Katherine P.; Rascovsky, Katya; Staffaroni, Adam M.; Tartaglia, Maria Carmela; Weintraub, Sandra; Wong, Bonnie; Boeve, Bradley F.; Boxer, Adam L.; Rosen, Howard J.; Goldman, Jill; Huey, Edward D.; Cosentino, Stephanie; ALLFTD consortium; Medical and Molecular Genetics, School of Medicine
    Although executive dysfunction is the characteristic cognitive marker of behavioral variant frontotemporal dementia (bvFTD), episodic memory deficits are relatively common, and may be present even during the prodromal disease phase. In a cohort of mutation carriers with mild behavioral and/or cognitive symptoms consistent with prodromal bvFTD, we aimed to investigate patterns of performance on an abbreviated list learning task, with a particular focus on recognition memory. We further aimed to characterize the cognitive prodromes associated with the three major genetic causes of frontotemporal dementia, as emerging evidence suggests there may be subtle differences in cognitive profiles among carriers of different genetic mutations. Participants included 57 carriers of a pathogenic mutation in microtubule-associated protein tau (MAPT, N = 23), or progranulin (GRN, N = 15), or a or a hexanucleotide repeat expansion in chromosome 9 open reading frame 72 (C9orf72, N = 19), with mild cognitive and/or behavioral symptoms consistent with prodromal bvFTD. Familial non-carriers were included as controls (N = 143). All participants completed a comprehensive neuropsychological examination, including an abbreviated list learning test assessing episodic memory recall and recognition. MAPT mutation carriers performed worse than non-carriers in terms of list recall, and had difficulty discriminating targets from distractors on the recognition memory task, primarily due to the endorsement of distractors as targets. MAPT mutation carriers also showed nonverbal episodic memory and semantic memory dysfunction (object naming). GRN mutation carriers were variable in performance and overall the most dysexecutive. Slowed psychomotor speed was evident in C9orf72 repeat expansion carriers. Identifying the earliest cognitive indicators of bvFTD is of critical clinical and research importance. List learning may be a sensitive cognitive marker for incipient dementia in MAPT and potentially a subset of GRN carriers. Our results highlight that distinct cognitive profiles may be evident in carriers of the three disease-causing genes during the prodromal disease stage.
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    Temporal order of clinical and biomarker changes in familial frontotemporal dementia
    (Springer Nature, 2022) Staffaroni, Adam M.; Quintana, Melanie; Wendelberger, Barbara; Heuer, Hilary W.; Russell, Lucy L.; Cobigo, Yann; Wolf, Amy; Goh, Sheng-Yang Matt; Petrucelli, Leonard; Gendron, Tania F.; Heller, Carolin; Clark, Annie L.; Taylor, Jack Carson; Wise, Amy; Ong, Elise; Forsberg, Leah; Brushaber, Danielle; Rojas, Julio C.; VandeVrede, Lawren; Ljubenkov, Peter; Kramer, Joel; Casaletto, Kaitlin B.; Appleby, Brian; Bordelon, Yvette; Botha, Hugo; Dickerson, Bradford C.; Domoto-Reilly, Kimiko; Fields, Julie A.; Foroud, Tatiana; Gavrilova, Ralitza; Geschwind, Daniel; Ghoshal, Nupur; Goldman, Jill; Graff-Radford, Jonathon; Graff-Radford, Neill; Grossman, Murray; Hall, Matthew G. H.; Hsiung, Ging-Yuek; Huey, Edward D.; Irwin, David; Jones, David T.; Kantarci, Kejal; Kaufer, Daniel; Knopman, David; Kremers, Walter; Lago, Argentina Lario; Lapid, Maria I.; Litvan, Irene; Lucente, Diane; Mackenzie, Ian R.; Mendez, Mario F.; Mester, Carly; Miller, Bruce L.; Onyike, Chiadi U.; Rademakers, Rosa; Ramanan, Vijay K.; Ramos, Eliana Marisa; Rao, Meghana; Rascovsky, Katya; Rankin, Katherine P.; Roberson, Erik D.; Savica, Rodolfo; Tartaglia, M. Carmela; Weintraub, Sandra; Wong, Bonnie; Cash, David M.; Bouzigues, Arabella; Swift, Imogen J.; Peakman, Georgia; Bocchetta, Martina; Todd, Emily G.; Convery, Rhian S.; Rowe, James B.; Borroni, Barbara; Galimberti, Daniela; Tiraboschi, Pietro; Masellis, Mario; Finger, Elizabeth; van Swieten, John C.; Seelaar, Harro; Jiskoot, Lize C.; Sorbi, Sandro; Butler, Chris R.; Graff, Caroline; Gerhard, Alexander; Langheinrich, Tobias; Laforce, Robert; Sanchez-Valle, Raquel; de Mendonça, Alexandre; Moreno, Fermin; Synofzik, Matthis; Vandenberghe, Rik; Ducharme, Simon; Le Ber, Isabelle; Levin, Johannes; Danek, Adrian; Otto, Markus; Pasquier, Florence; Santana, Isabel; Kornak, John; Boeve, Bradley F.; Rosen, Howard J.; Rohrer, Jonathan D.; Boxer, Adam L.; Frontotemporal Dementia Prevention Initiative (FPI) Investigators; Medicine, School of Medicine
    Unlike familial Alzheimer’s disease, we have been unable to accurately predict symptom onset in presymptomatic familial frontotemporal dementia (f-FTD) mutation carriers, which is a major hurdle to designing disease prevention trials. We developed multimodal models for f-FTD disease progression and estimated clinical trial sample sizes in C9orf72, GRN, and MAPT mutation carriers. Models included longitudinal clinical and neuropsychological scores, regional brain volumes, and plasma neurofilament light chain (NfL) in 796 carriers and 412 non-carrier controls. We found that the temporal ordering of clinical and biomarker progression differed by genotype. In prevention-trial simulations employing model-based patient selection, atrophy and NfL were the best endpoints, whereas clinical measures were potential endpoints in early symptomatic trials. F-FTD prevention trials are feasible but will likely require global recruitment efforts. These disease progression models will facilitate the planning of f-FTD clinical trials, including the selection of optimal endpoints and enrollment criteria to maximize power to detect treatment effects.