Flortaucipir PET Imaging in Subjects With FTD

Inclusion Criteria: * Subjects diagnosed by a dementia specialist with symptomatic clinical syndromes with expected Frontotemporal Dementia (FTD) pathology will be enrolled. Clinical syndromes associated with FTD pathology include: behavioral-variant FTD, FTD with motor-neuron disease, non-fluent/agrammatic and semantic variants of primary progressive aphasia, progressive supranuclear palsy syndrome and corticobasal syndrome. * Have provided informed consent or have a legally authorized (LAR) provide consent for study procedures * Have had volumetric brain MRI obtained in site's companion protocol within one year of enrollment * Can tolerate PET scan procedures Exclusion Criteria: * Have clinically significant cardiac, hepatic, renal, pulmonary, metabolic, or endocrine disturbances that pose potential safety risk * Have history of risk factors for Torsades de Pointes (TdP) or taking medication known to cause QT prolongation * Have history of drug or alcohol dependence within the last year * Are females of childbearing potential who are not surgically sterile, not refraining from sexual activity, or not using reliable contraception * Have history of relevant severe drug allergy or hypersensitivity * Have received an investigational medication under FDA IND protocol within 30 days of planned imaging session * Have received a radiopharmaceutical for imaging/therapy within 24 hours of imaging session * Possess PET scan evidence of amyloid deposition * Determined by the investigator to be unsuitable for this type of study