Clinical Trial: PiB PET Scanning in Speech and Language Based Dementias

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: PiB PET Scanning in Speech and Language Based Dementias

Brief Summary: The study is designed to determine whether there are clinical features that can be used as biomarkers to predict whether underlying Alzheimer's pathology is the cause of a speech and language based dementia. The primary hypothesis is that the proportion of patients who test positive for beta-amyloid deposition will vary across different speech and language based dementias.

Detailed Summary:

Speech and language based dementias (SLDs) (often referred to as primary progressive aphasias or PPA) are neurodegenerative diseases in which speech or language impairments are the most salient features of the disease and explain deficits in activities of daily living. Patients with SLDs may have poor grammar, prominent anomia, comprehension deficits, speech production and articulation problems, difficulty with repetition of words or sentences, word finding pauses, or a combination of all these features. The SLDs can be further divided into different subtypes. Up to 50% of patients with SLDs that go on to autopsy have shown Alzheimer type pathology where beta-amyloid deposition is observed; the rest have pathology consistent with frontotemporal lobar degeneration where beta-amyloid deposition is absent. Future disease modifying treatments that target beta-amyloid will most likely differ from treatments that do not target beta-amyloid. As a consequence, biomarkers are needed to differentiate patients with SLDs with and without beta-amyloid deposition.

Little research has been done to identify biomarkers that could differentiate patients with SLDs with and without beta-amyloid, mainly because the gold standard to identify the presence of beta-amyloid has been pathological examination, which does not always occur, and may not occur until more than 10 years after onset. The recent development of [N-methyl-11C]2-(4'-methylaminophenyl)-6-hydroxybenzothiazole also known as 11C Pittsburgh Compound B or PiB is a solution to this problem since PiB allows the in vivo detection of beta-amyloid. Unfortunately, PiB is very expensive.

The long term goal of our research is to develop a cost effective algorithmic approach to the evaluation and diagnosis of patients presenting with SLDs. The objective of the studies outlined in this proposa
Sponsor: Mayo Clinic

Current Primary Outcome: Percentage of patients with different speech and language based dementia (SLD) subtypes who have a [N-methyl-11C]2-(4'-methylaminophenyl)-6-hydroxybenzothiazole (PiB) positive positron emission tomography (PET) scan at presentation [ Time Frame: Study entry, approximately day 1 or day 2 of study ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Percentage of patients who exhibit apraxia of speech as measured by the Apraxia of Speech Rating Scale at presentation [ Time Frame: Study entry, approximately day 1 or day 2 of study ]
    Apraxia of Speech Rating Scale has been developed by the speech pathologists involved in this study, and has tested to be reliable. The scale ranges from 0-4; 0=apraxia of speech not present, 4=apraxia of speech nearly always evident and marked in severity.
  • Temporoparietal hypometabolism as shown on [18-F]-fluoro-deoxy-glucose positron emission tomography (FDG-PET) scan at presentation [ Time Frame: Study entry, approximately day 1 or day 2 of study ]
  • Grey matter loss as shown on magnetic resonance imaging (MRI) at presentation [ Time Frame: Study entry, approximately day 1 or day 2 of study ]


Original Secondary Outcome: Same as current

Information By: Mayo Clinic

Dates:
Date Received: June 7, 2012
Date Started: March 2010
Date Completion:
Last Updated: December 21, 2015
Last Verified: December 2015