A Study of LY3002813 in Participants With Early Symptomatic Alzheimer's Disease (TRAILBLAZER-ALZ)

Integrated Alzheimer's Disease Rating Scale is used to assess whether donanemab slows down the cognitive and functional decline associated with AD compared with placebo. iADRS is a simple linear combination of 13-item alzheimer's disease assessment scale-cognitive subscale (ADAS-Cog13) and the Alzheimer's disease cooperative study-instrumental activities of daily living scale (ADCS-iADL). The scale ranges from 0 to 144, where lower scores indicate worse performance and higher score indicates better performance. Least Squares (LS) Mean value was controlled for fixed, categorical effects of treatment, visit and treatment-by-visit interaction, pooled investigator, acetylcholinesterase inhibitor (AChEI) and/or memantine use at baseline, as well as the continuous, fixed covariates of baseline, baseline-by-visit, and age at baseline.

The ADAS is a rater administered instrument that was designed to assess the severity of the dysfunction in the cognitive and noncognitive behaviors characteristic of persons with AD. The cognitive subscale of the ADAS consists of 13 items assessing areas of cognitive function most typically impaired in AD: orientation, verbal memory, language, praxis, delayed free recall, digit cancellation. The ADAS--Cog13 scale ranges from 0 to 85. Higher scores indicate greater disease severity. LS Mean value was controlled for fixed, categorical effects of treatment, visit and treatment-by-visit interaction, pooled investigator, AChEI and/or memantine use at baseline, as well as the continuous, fixed covariates of baseline, baseline-by-visit, and age at baseline.

CDR-SB is a semi-structured interview of participants and their caregivers. Participant's cognitive status is rated across 6 domains of functioning, including memory, orientation, judgment/problem solving, community affairs, home/hobbies, and personal care. Severity score assigned for each of 6 domains; Total score (SB) ranges from 0 to 18. Higher scores indicate greater disease severity. LS Mean value was controlled for fixed, categorical effects of treatment, visit and treatment-by-visit interaction, pooled investigator, AChEI and/or memantine use at baseline, as well as the continuous, fixed covariates of baseline, baseline-by-visit, and age at baseline.

MMSE is a brief screening instrument used to assess cognitive function (orientation, memory, attention, ability to name objects, follow verbal/written commands, write a sentence, and copy figures). Total score ranges from 0 to 30; lower score indicates greater disease severity. LS Mean value was controlled for fixed, categorical effects of treatment, visit and treatment-by-visit interaction, pooled investigator, AChEI and/or memantine use at baseline, as well as the continuous, fixed covariates of baseline, baseline-by-visit, and age at baseline.

The ADCS-ADL is a 23-item inventory developed as a rater-administered questionnaire answered by the participant's caregiver. The ADCS-ADL measures both basic and instrumental activities (instrumental activity items 6a, 7-23) of daily living by participants. The range for the ADCS-iADL is 0-59 with higher scores reflecting better performance. LS Mean value was controlled for fixed, categorical effects of treatment, visit and treatment-by-visit interaction, pooled investigator, AChEI and/or memantine use at baseline, as well as the continuous, fixed covariates of baseline, baseline-by-visit, and age at baseline.

Florbetapir PET imaging was used as a quantitative amyloid biomarker. Florbetapir PET scans at baseline and at 76 weeks after the first treatment were used to quantitatively estimate change in amyloid plaques. Quantitative amyloid burden was first formalized as the average Standardized Uptake Value Ratio (SUVR) in six predetermined cortical areas of the brain relative to the cerebellum as a reference region. Larger SUVR reflects the larger cortical amyloid burden relative to cerebellum. SUVR values were further calibrated to a centiloid (CL) scale. The Centiloid scale anchor points are 0 and 100, where 0 represents a high-certainty amyloid negative scan and 100 represents the amount of global amyloid deposition found in a typical AD scan. Least Squares mean change was controlled for fixed, categorical effects of treatment, visit and treatment-by-visit interaction, as well as the continuous, fixed covariates of baseline, baseline-by-visit, and age at baseline.

Flortaucipir PET imaging was used as a quantitative tau biomarker. Flortaucipir PET scans at baseline and at 76 weeks after the first treatment were used to quantitatively estimate change in aggregated tau neurofibrillary tangles (NFTs). Quantitative tau burden was formalized using two measures: weighted average Standardized Uptake Value Ratio (MUBADA SUVR) in the brain relative to the cerebellum gray as a reference region and the global tau load (TauL) generated using a TauIQ method. Larger weighted average SUVR reflects the larger cortical tau burden relative to cerebellum gray. The TauIQ method quantifies the spatiotemporal accumulation pattern of tau and larger TauL value reflects the larger global tau level in the brain as determined using a TauIQ mathematical framework. Least Squares mean change was controlled for baseline + age + treatment (Type III sum of squares).

MRI scans at baseline and at 76 weeks after the first treatment were used to quantitatively estimate change in brain atrophy. Volumetric MRI (vMRI) parameters were measured in 14 brain regions: bilateral cortical, bilateral entorhinal cortex, bilateral hippocampus, bilateral inferior parietal lobe, bilateral isthmus cingulate, bilateral lateral parietal lobe, bilateral medial temporal lobe, bilateral precuneus, bilateral prefrontal lobe, bilateral superior temporal lobe, bilateral ventricles, bilateral whole brain, bilateral whole temporal lobe, and bilateral white matter. The atrophy was assessed by tensor-based morphometry, which captures volume changes within the deformation map. LS Mean value was controlled for fixed, categorical effects of treatment, visit and treatment-by-visit interaction, fixed covariates of baseline, and age at baseline.