This study will evaluate whether visual interpretation of flortaucipir-PET (positron emission tomography) scans, examining patterns of tracer uptake at baseline, can predict the rate of clinically-meaningful cognitive decline due to AD after 18 months. All scans are acquired from cohorts of a previously completed study, I8D-MC-AZES (NCT02245737, lanabecestat, Eli Lilly and Company sponsor).
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
DIAGNOSTIC
Masking
NONE
Enrollment
205
No study drug will be administered. Scans previously acquired from Study I8D-MC-AZES (NCT02245737, Eli Lilly and Company sponsor) at baseline will be read by independent, blinded readers. IV injection, 240 megabecquerel (MBq) (6.5 mCi), single dose in AZES
positron emission tomography (PET) scan of the brain
American College of Radiology
Philadelphia, Pennsylvania, United States
Risk Ratio for AD Symptom Progression on CDR-SB
Baseline flortaucipir F 18 PET imaging results were determined by majority read (see Baseline Characteristics for description). Clinically meaningful deterioration (CMD) was defined for the primary endpoint as a worsening of the Clinical Dementia Rating Scale Sum of Boxes (CDR-SB) score of one point or more. The clinical dementia rating (CDR) examines 6 categories of cognitive functioning domains. Each domain is scored on a scale ranging from 0 to 3 (including 0.5). A CDR-SB was generated as the sum of the values in each of the 6 domains. The CDR-SB sum scores range from 0 to 18, with higher scores indicating greater cognitive impairment and a 1 point worsening is considered a clinically significant symptom change.
Time frame: Within 18 months of scan
Risk Ratio for AD Symptom Progression on Various Clinical Measures
Baseline flortaucipir F 18 PET imaging results were determined by majority read (see Baseline Characteristics for description). Clinically meaningful deterioration (CMD) was defined for the cognitive endpoints as follows: mini-mental status exam (MMSE) worsening of 3 points or greater, Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog11) worsening of 4 points or greater, Pfeffer's Functional Activities Questionnaire (FAQ) worsening of 3 points or greater, CDR global worsening of greater than 0 points. MMSE scores range from 0 to 30 with lower scores indicating worsening cognitive function. ADAS-Cog11 scores range from 0 to 70 with higher scores indicating worsening cognitive function. FAQ scores range from 0 to 30 with higher scores indicating worsening cognitive function. CDR global is scored on a 5 point scale (0, 0.5, 1, 2, 3) with higher scores indicating worsening cognitive function.
Time frame: Within 18 months of scan
Mean Change in Cognitive/Functional Assessments
Mean change in cognitive/functional measures baseline between τAD++ and non-τAD++ (determined by baseline tau status), calculated by Mixed Model Repeat Measures (MMRM). CDR-SB scores range from 0 to 18, with higher scores indicating worsening cognitive impairment. MMSE scores range from 0 to 30 with lower scores indicating worsening cognitive function. ADAS-Cog11 scores range from 0 to 70 with higher scores indicating worsening cognitive function. FAQ scores range from 0 to 30 with higher scores indicating worsening cognitive function.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Time frame: baseline and 18 months
Inter-Reader Reliability of Reader Interpretation of Flortaucipir F 18 PET Imaging
As measured by Fleiss' Kappa across all scans read. Fleiss' kappa is a statistical measure for assessing the reliability of agreement between a fixed number of raters when assigning categorical ratings to a number of items or classifying items. Fleiss' kappa can range from -1 to 1 with 1 indicating perfect agreement between the readers. Read results binarized as τAD++ or non-τAD++.
Time frame: baseline scan