ECTRIMS 2018 BERLIN, GERMANY

J Kuhle (1), C Barro(1), K Hrusovsky(2), L Chang(2), A Jeromin(2), C Bridel()3, A Bar-Or(4), S Bittner(5), W Brück(6), B Bielekova(7), T Chitnis(8), G Comi(9), M Comabella(10), G Arrambide(10), X Montalban(10), A Datwani(11), M Fluck(12), R Fox(13), M Freedman(14), R Furlan(9), S Gnanapavan(15), G Giovannoni(15), E Havari(16), M Khalil(17), D Leppert(18), H Kropshofer(18), MA Valentin(18), J Oksenberg(19), F Piehl(20), T Plavina(21), MP Sormani(22), S Lehmann(23), E Thouvenot(24), T Ziemssen(25), F Zipp(5), C Gross(26), H Wiendl(26), L Kappos(1), Z Michalak(1), K Blennow(27), H Zetterberg(18), C Teunissen(3), D Wilson(2).

1 Neurologic Clinic and Policlinic, University Hospital Basel, Switzerland; 2 Quanterix Corp, Cambridge, Massachusetts, United States; 3 Department of Clinical Chemistry, VU University Medical Center  Amsterdam, The Netherlands; 4 Department of Neurology, University of Pennsylvania, Philadelphia, USA; 5 Department of Neurology, Johannes Gutenberg University Mainz, Mainz, Germany. 6 Institute of Pathology, University Medical Centre Göttingen, Germany; 7 Neuroimmunological Diseases Unit, National Institutes of Health (NIH), Bethesda, Maryland, USA; 8 Partners Multiple Sclerosis Center, Brigham and Women’s Hospital, Boston, USA; 9 Department of Neurology, Università Vita-Salute San Raffaele, Milan, Italy; 10 Neurology-Neuroimmunology Department & Neurorehabilitation Unit, Multiple  Sclerosis Centre of Catalonia (Cemcat), Vall d’Hebron University Hospital, Barcelona, Spain;  11 Genentech, South San Francisco, CA, USA; 12 Merck, Darmstadt, Germany. 13 Mellen Centre for Multiple Sclerosis Treatment and Research, Cleveland Clinic, Cleveland, OH, USA. 14 Department of Medicine-Neurosciences, University of Ottawa, Ontario, Canada. 15 Blizard Institute, Queen Mary University of London, UK; 16 Genzyme, a Sanofi Company, Framingham, MA, USA; 17 Department of Neurology, Medical University of Graz, Austria; 18 Novartis Pharma AG, Basel, Switzerland, 19 Department of Neurology, University of California, San Francisco, CA, USA; 20 Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden; 21 Biogen Inc., Cambridge, MA, USA; 22 Biostatistics Unit, Department of Health Sciences, University of Genoa, Genoa, Italy; 23 Centre Hospitalier Universitaire de Montpellier, Montpellier, France; 24 Service de Neurologie, Hôpital Caremeau, CHU de Nîmes, Nîmes, France; 25 Center of Clinical Neuroscience, University Hospital, Dresden, Germany; 26 Department of Neurology, University of Münster, Münster, Germany; 27 Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Mö lndal, Sweden.

Background:

Neurofilament light chain (NfL) is an exclusively neuronal protein showing increased levels in blood upon neuroaxonal injury in various neurological diseases. For the first time highly sensitive NfL measurements in blood open the option for a sensitive assessment of the consequences of brain tissue damage. Measurement of peripheral blood NfL levels in multiple sclerosis (MS) is emerging as a biomarker of disease activity, treatment response and short and longer-term prognosis.

Establishing a normative multi-centre applicable database for NfL, including potential confounding by metabolic illnesses, other CNS diseases and age, is a key development step for a potential application in clinical trials and individual therapeutic decision making. As a prerequisite, we aimed at analytically validating the Simoa NF-light assay from Quanterix within the MSNfL Working group.

Methods:

The single molecule array (Simoa) assay technology is significantly more sensitive compared to conventional detection systems like ELISA or electrochemiluminescence immunoassays. Simoa allows reliable detection of NfL in individual serum samples.

Results:

As of May 2018, 11 centres have confirmed participation in the multisite analytical validation of the Simoa NF-light assay. All centres have agreed to perform 6 kit runs on individual days according to a standardized protocol and common materials. We will report data on assay sensitivity, parallelism (between calibrators and samples) and within- and across site comparability. We will also present results on centrally blinded serum samples from well-characterized MS patients in various different concentration ranges for analyzing consistency of NfL concentrations across sites.

Conclusions:

Coordinated multicentre research activities are under way to develop NfL as a body fluid marker that may accurately reflect brain tissue damage and allows monitoring disease activity and drug effects in clinical practice. To date, the main limitations towards an application in individual disease monitoring is the lack of normative data for NfL across a broad range of age groups and understanding how comorbidities affect blood NfL concentrations. The goal of this assay validation is to establish standardized and accurate NfL measurements across sites. Our results will inform about the precision and robustness of the NfL assay in a multi-centre setting and will facilitate future establishment of broadly applicable NfL reference ranges.