JPND - Defining measures of proximity to symptom onset in the GENetic Frontotemporal dementia Initiative

Frontotemporal dementia (FTD) is a highly heritable neurodegenerative disorder with the majority of that heritability accounted for by autosomal dominant mutations in three genes: progranulin (GRN), microtubule-associated protein tau (MAPT) and chromosome 9 open reading frame 72 (C9orf72). The Genetic FTD Initiative (GENFI) is a European and Canadian multicentre natural history study of genetic FTD with detailed phenotyping of both presymptomatic and symptomatic mutation carriers. In the absence of treatments that can delay the onset or prevent the progression of genetic FTD, the aim of GENFI has been to identify robust biomarkers for future trials. However, with trials imminent, it will be critically important to identify biomarkers of proximity to symptom onset, identifying on an individual basis those who are likely to progress to clinical FTD over the next 5 to 10 years. The aim of this study is therefore to characterize the prodromal period of genetic FTD, establishing cognitive, imaging and fluid biomarker measures that allow i) stratification of individual presymptomatic carriers into a stage proximal to symptom onset, and ii) measurement of subsequent disease progression during that proximal period. In particular, the work will extend the results found on a group basis in the prior GENFI studies to identify measures and patterns of change on an individual basis, thus paving the way for a precision medicine approach to FTD. It will make use of data from at least 950 participants already in the current GENFI studies with biomarker data acquired longitudinally (>2000 visits so far). It will focus on those likely to be in proximity to symptom onset, following 500 participants over time, with cognitive, neuroimaging, and fluid biomarker assessment as well as genomic, proteomic and transcriptomic profiling of participants. Integration of these approaches will allow stratification of genetic FTD, delineating an individualized disease profile that identifies those in proximity to symptom onset and their subsequent progression. This will be fundamental to rational trial design involving presymptomatic participants over the next few years - such trials will not be possible without this.

Frontotemporal dementia (FTD) is a highly heritable neurodegenerative disorder with the majority of that heritability accounted for by autosomal dominant mutations in three genes: progranulin (GRN), microtubule-associated protein tau (MAPT) and chromosome 9 open reading frame 72 (C9orf72). The Genetic FTD Initiative (GENFI) is a European and Canadian multicentre natural history study of genetic FTD with detailed phenotyping of both presymptomatic and symptomatic mutation carriers. With trials imminent, it will be critically important to identify biomarkers of proximity to symptom onset, identifying on an individual basis those who are likely to progress to clinical FTD over the next 5 to 10 years. The aim of this study is therefore to characterize the prodromal period of genetic FTD, establishing cognitive, imaging and fluid biomarker measures that allow i) stratification of individual presymptomatic carriers into a stage proximal to symptom onset, and ii) measurement of subsequent disease progression during that proximal period. In particular, the work will extend the results found on a group basis in the prior GENFI studies to identify measures and patterns of change on an individual basis, thus paving the way for a precision medicine approach to FTD. It will make use of data from at least 950 participants already in the current GENFI studies with biomarker data acquired longitudinally (>2000 visits so far). It will focus on those likely to be in proximity to symptom onset, following 500 participants over time, with cognitive, neuroimaging, and fluid biomarker assessment as well as genomic, proteomic and transcriptomic profiling of participants. Integration of these approaches will allow stratification of genetic FTD, delineating an individualized disease profile that identifies those in proximity to symptom onset and their subsequent progression.

The outcomes of this study will lead to improvement in the recognition and diagnosis of genetic FTD as well as provide improved prognostic information for patients and members of their family in the first instance. GENFI-prox will provide a platform for clinical trials in genetic FTD: finding a disease-modifying therapy in this disorder will be hugely beneficial both for the patient and their families at risk of the disorder, as well as improving the nation's health and wealth by altering a disease process that affects people generally of working age. Based on the current understanding of the pathophysiology of the disease, it is probable that effective interventions for genetic FTD due to progranulin mutations will become available either by repurposing or from novel agents.

The outcomes of GENFI-prox in terms of biomarkers of disease onset and progression will feed into pharmaceutical industry-led studies, providing the knowledge required to identify the primary and secondary outcomes used in clinical trials and the timing of when the trials should take place.