The UK GENetic Frontotemporal dementia Initiative (UK GENFI)

Frontotemporal dementia (FTD) is a common cause of young onset dementia. Its effect on people of working age with young families represents a major health and economic burden on society. The only known risk factors for FTD at present are genetic with abnormalities (mutations) in three genes accounting for the majority of familial FTD, called progranulin, tau and chromosome 9 open reading frame 72. There are now promising avenues for treatment of these disorders but we still do not know when drugs should be started or how we should measure the response to treatment. This study investigates people who have genetic (inherited) FTD, including both people who have developed symptoms and also their first-degree relatives who are at 50% risk of carrying the genetic mutation and therefore developing symptoms in the future. By studying individuals who carry the disease mutation and are thus destined to develop the disease we can understand the development from the very earliest changes, which would be the best time to start any treatment whilst the person remains well. A pilot phase of the study between 2011 and 2014 has created a common platform for studying genetic FTD and a standardized testing protocol. This study builds on the pilot phase by creating a UK-wide study of genetic FTD (at University College London, University of Cambridge, University of Manchester and the University of Oxford) over the next five years. It is expected that 200 participants will be seen, being assessed three times in total. Study participants will have psychology testing (tests of memory, language, behaviour etc.), brain imaging, blood tests and spinal fluid collection (by lumbar puncture) in order to investigate the patterns of change in these different tests at different stages of the disorder. The key outcomes of the study are to (1) improve understanding of how brain systems break down in genetic FTD and how this breakdown relates to the underlying behavioural and cognitive symptoms, (2) develop markers which help identify the disease at its earliest stage, and (3) develop markers that allow the progression of the disease to be tracked. The eventual aim will be to use these markers in future clinical trials of drugs in genetic FTD. The results of this project will also lead to improvement in the recognition and diagnosis of genetic FTD as well as provide improved information about prognosis for patients and members of their family.

Frontotemporal dementia (FTD) is a common cause of young onset dementia, approximately equal in frequency to Alzheimer's disease in people below the age of 65. Its effect on people of working age with young families represents a major health and economic burden on society. The only known risk factors for FTD are genetic, and around a third of FTD is familial. There are currently no treatments that can delay the onset or prevent the progression of genetic FTD but there are now potential disease-modifying therapies in development. However, there are still no biomarkers of genetic FTD that can confidently predict when disease-modifying therapy should be initiated or how the response to it should be monitored. By studying participants who carry a mutation and are thus destined to develop the disease we can explore the entire disease pathway, using mutation negative first-degree relatives as controls. A pilot study has created a common methodological platform to study genetic FTD. This follow-on study aims to capitalize on the work of the pilot, extending both the platform and expertise generated to a UK-wide study of genetic FTD. Specifically, we will establish a UK-wide familial FTD cohort of 200 participants which will (1) lead to greater understanding of the biological underpinning of the cognitive and behavioural deficits seen in FTD; (2) permit large-scale cohesive and integrated longitudinal biomarker studies of familial FTD with the specific remit of informing clinical trial design; and (3) provide a "readiness" cohort of patients for disease-modifying drug trials. The experimental plan includes longitudinal clinical and neuropsychological assessments, neuroimaging and both blood and spinal fluid sampling, with the key outcomes including improved understanding regarding the selective vulnerability of the specific neural systems affected in FTD, robust biomarkers of disease onset and progression, and estimation of sample sizes required for trials.

The outcomes of UK GENFI 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. UK GENFI will provide a platform for clinical trials in genetic FTD, likely to occur in the next five years: 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. Rapid evaluation will support the G8 declaration of a treatment for dementia by 2025. This would have significant UK political benefit building on the UK lead internationally in the G8 dementia summit.

The outcomes of UK GENFI 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.