Sysmex and Eisai Present New Data on Blood-Based Diagnostic Method for Alzheimer's Disease at CTAD 2020

TOKYO, Dec. 11, 2020 /PRNewswire/ -- Sysmex Corporation (Headquarters: Kobe, Japan; Chairman and CEO: Hisashi Ienaga; hereinafter referred to as "Sysmex") and Eisai Co., Ltd. (Headquarters: Tokyo, Japan; CEO: Haruo Naito; hereinafter referred to as "Eisai") announced that the latest data from their joint project to develop a plasma-based diagnostic method for Alzheimer's disease (AD) were presented at the 13th Clinical Trials on Alzheimer's Disease (CTAD) Conference, held from November 4 to 7, 2020. Sysmex, on behalf of both companies, presented findings using the Sysmex HISCL^TMPlasma β-Amyloid Measured by Fully Automated Immunoassay Analyzer（Aβ）Performance in predicting amyloid pathology, with amyloid pathology determined using the Centiloid scale from amyloid positron emission tomography (PET) imaging^[1]。

Clinical Trials:
Biomarkers (including plasma)
LP10

Plasma Aβ Ratio Measured by Fully Automated Immunoassay Analyzer Predicts the Presence of Amyloid Pathology
(Determined using the Aβ-PET imaging Centiloid scale)
Poster Display: November 4 (Wednesday) to November 7 (Saturday)

To date, our research group has consistently employed the visual image interpretation methods commonly used in clinical trials.^[2], via amyloid PET scan
scans to confirm amyloid pathology. However, an increasing number of recent research studies have employed the SUVR (Standardized Uptake Value Ratio) metric to assess amyloid
Quantitative evaluation of amyloid PET images was performed, and correction was applied using a standardized technique known as the Centiloid method, to determine
Quantitative Assessment of Amyloid Pathology^[3]. Therefore, to evaluate plasma Aβ measured by the fully automated immunoassay system HISCL_1-42/Aβ_1-40(Aβ ratio)
In terms of performance in predicting amyloid pathology, we analyzed 149 cases clinically diagnosed with MCI (mild cognitive impairment) and mild AD,
Amyloid pathology was assessed using visual reading and the Centiloid scale to determine the differences in predictive performance between these two methods.
The results confirmed that the Centiloid scale method demonstrated superior performance in identifying amyloid pathology, with a sensitivity and specificity of 78% (AUC = 0.82).
The sensitivity and specificity of the visual interpretation method were 72% and 71%, respectively (AUC = 0.74). Furthermore, it was determined that
Correlation between Plasma Aβ Ratio and Centiloid Score (Spearman Rank Correlation Coefficient (r_s)^[4] = -0.57，p<0.0001），
Compared with previous results, it provides stronger evidence that plasma Aβ ratios can predict cerebral amyloid pathology. Furthermore, many plasma
Cases of discordance between the Aβ ratio and the Centiloid scale are considered false positives (i.e., positive plasma Aβ ratio but negative amyloid PET Centiloid).
Other research groups have also reported such inconsistencies, suggesting that these false-positive subjects, compared to negative subjects
More likely to have a positive amyloid PET imaging result^[5]. Based on these findings, the fully automated immunoassay system HISCL is considered
The measured plasma Aβ ratio may reflect earlier-stage cerebral amyloid pathology that is undetectable by amyloid PET imaging.
To further evaluate the clinical utility of our detection system, we will assess additional samples.

Sysmex Corporation(www.sysmex.co.jp)  

The global number of people with dementia is projected to reach 82 million by 2030 and 152 million by 2050. The total global social cost of dementia, comprising direct medical costs, social care costs, and productivity losses, is estimated to reach US$2 trillion by 2030.^[6]. In Japan, the number of patients with dementia reached approximately 4.62 million in 2012 and is projected to increase to 7.3 million by 2025.^[7], it is estimated that the total social cost of this disease in 2025 will be equivalent to 4.1% of the gross domestic product (GDP)^[8](25.8 trillion yen^[9]). Among these dementia patients, those with AD account for more than 60%.^[7]。

Alzheimer’s disease (AD) is known to be a disorder triggered by the extracellular aggregation of amyloid-beta (Aβ) protein, which induces intracellular tau protein deposition, leading to synaptic dysfunction and neuronal cell death. These brain changes can cause cognitive impairment and neuropsychiatric symptoms, suggesting that Aβ aggregation and accumulation in the brain occur prior to the onset of cognitive impairment. Therefore, early diagnosis and early intervention are considered more effective in Aβ-targeted therapies. Currently, the methods for detecting cerebral amyloid aggregation are amyloid positron emission tomography (PET) imaging and cerebrospinal fluid (CSF) Aβ ratio assays; however, both approaches impose a substantial burden on patients in terms of accessibility, cost, and physical invasiveness.^[10]。

Sysmex and Eisai are working to develop new diagnostic technologies for the prevention and treatment of dementia. Their primary goal is to advance healthcare and improve the quality of life for patients with dementia and their families.

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