Validation of Ella Platform for Serum Nfl And GFAP Measures In Multiple Sclerosis Patients

Study Overview
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Brief Summary
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Serum neurofilament-light chain (NfL) and glial fibrillary acidic protein (GFAP) measured by single molecule array (SIMOA) are novel biomarkers of multiple sclerosis patients (MS) activity and progression. Its use is limited due to low availability and high costs. ELLA is a cheaper platform with increasing availability. Recently, we compared SIMOA and ELLA platforms to assess serum NfL levels in 203 MS patients from the OFSEP-HD study. There was a strong correlation (Spearman r = 0.86, p < 0.0001) between both platforms. As for SIMOA, serum NfL levels measured by ELLA were correlated with age and EDSS and were significantly higher in active MS, suggesting that these assays are equivalent and can be used in any center for routine care. However, the accuracy of local measures acquired with ELLA has not been determined. The aim os this study is to assess the concordance of multi-site ELLA instruments, accuracy of GFAP measures as compared to SIMOA, and the predictive value of NfL and GFAP measured by ELLA in MS.

Official Title
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Multi-Site Validation of Ella Platform for Serum Nfl And GFAP Measures In Multiple Sclerosis Patients

Conditions
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Multiple Sclerosis

Intervention / Treatment
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* Other: Biomarker quantification


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients from the OFSEP HD cohort. At least one native (no thaw-freeze cycle) serum sample in local or in centralized Biological Resource Center Exclusion Criteria: No bio-collection or insufficient sample volume No OFSEP minimal sheet at baseline

Ages Eligible for Study
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Minimum Age: 15 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with multiple sclerosis<br> | Other: Biomarker quantification<br>* Patient blood samples will be tested on 2 different platforms<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inter-laboratory reproducibility of neurofilament-light chain level measurements | Coefficients of variation will be calculated in 30 patients | Day 0 | 
| Inter-laboratory repeatability of neurofilament-light chain level measurements | Serum from 3 patients with low, medium or high levels of NfL will be tested 10 times | Day 0 | 
| Inter-laboratory reproducibility and repeatability of glial fibrillary acidic protein level measurements | Coefficients of variation will be calculated in 30 patients | Day 0 | 
| Inter-laboratory repeatability of glial fibrillary acidic protein level measurements | Serum from 3 patients with low, medium or high levels of GFAP will be tested 10 times | Day 0 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| compare the GFAP values obtained using the ELLA and SIMOA platforms in MS patients | Intraclass concordance correlation coefficient and Passing-Bablock analysis calculated in 210 patients | Day 0 | 
| to build a global disease activity score | Logistic regression to predict active multiple sclerosis | Day 0 | 
| to build a global disability score | Logistic regression to predict Expanded Disability Status Scale score | Day 0 |