Predictive nature of IgM anti-α-glucose serum biomarker for relapse activity and EDSS progression in CIS patients: a BENEFIT study analysis

BACKGROUND Higher serum levels of at least one of a panel of four α-glucose IgM antibodies (gMS-Classifier1) in clinically isolated syndrome (CIS) patients are associated with imminent early relapse within 2 years. OBJECTIVE The objective of this study was to determine the prognostic value of gMS-Classifier1 in a large study cohort of CIS patients. METHODS The BEtaseron(®) in Newly Emerging multiple sclerosis For Initial Treatment (BENEFIT) 5-year study was designed to evaluate the impact of early versus delayed interferon-β-1b (IFNβ-1b; Betaseron(®)) treatment in patients with a first event suggestive of multiple sclerosis (MS). Patients (n = 258, 61% of total) with a minimum of 2 ml baseline serum were eligible for the biomarker study. gMS-Classifier1 antibodies' panel (anti-GAGA2, anti-GAGA3, anti-GAGA4 and anti-GAGA6) levels were measured blinded to clinical data. Subjects were classified as either 'positive' or 'negative' according to a classification rule. RESULTS gMS-Classifier1 was not predictive for the time to clinically definite MS or time to MS according to the revised McDonald's criteria, but did significantly predict an increased risk for confirmed disability progression (log-rank test: p = 0.012). CONCLUSIONS We could not confirm previous results that gMS-Classifier1 can predict early conversion to MS in CIS. However, raised titres of these antibodies may predict early disability progression in this patient population.