 Expected results and perspectives: The main expected result is the confirmation of the efficacy of memantine as a treatment for FTD, which would set a precedent in the treatment of this disease. Such a result could also lead the way to the development of treatments for other related neurodegenerative disorders tauopathies such as the other frontotemporal lobar degenerations semantic dementia, progressive non-fluent aphasia, progressive supranuclear palsy, or corticobasal degeneration. Finally, the standardized follow-up of a 64 patient cohort in this study will provide important information on the natural history of a rare and poorly-known disease. 