title: Neutralizing antibodies in multiple sclerosis patients treated with 375 micrograms interferon-beta-1b.
abstract: BACKGROUND
  Neutralizing antibodies (NAbs) to IFN-beta may have a detrimental effect on treatment response, but increasing IFN-beta dose could reduce their occurrence. The OPTimization of Interferon for MS (OPTIMS) study was a multicenter trial investigating clinical and MRI outcomes with the approved IFN-beta-1b dose (250 microg) and a higher dose (375 microg), s.c. every other day.
  
  
  OBJECTIVE
  To analyze the occurrence of NAbs and their effect on clinical and MRI response over a long-term (4-year) follow-up using cross-sectional and longitudinal statistical analysis.
  
  
  METHODS
  Relapses or disease progression was assessed open-label and MRI scans were performed serially during the first year of the study. Neutralizing antibodies were measured using the MxA protein production neutralization assay.
  
  
  RESULTS
  A total of 145 patients with relapsing-remitting multiple sclerosis from 14 centers participated in the study. Neutralizing antibody frequency was negatively associated with MRI treatment response, but no detrimental effect of NAbs on the clinical response was observed. Results obtained using cross-sectional or longitudinal statistical approaches were similar. Over the 4-year period, NAb-positive patients treated with 375 microg had a significantly greater probability of NAb disappearance (hazard ratio: 3.41; 95% confidence interval: 1.78 - 6.43; p < 0.01).
  
  
  CONCLUSIONS
  Use of an IFN-beta-1b dose higher than the currently approved 250-microg dose is associated with an increased probability of NAb disappearance. The OPTIMS study was registered at ClinicalTrials.gov: NCT00473213.
authors.affiliation: Division of Neurology, San Luigi Gonzaga University Hospital, Regione Gonzole, 10, I 100143 Orbassano, Turin, Italy. luca.durelli@unito.it
authors.forename: L
authors.initials: L
authors.lastname: Durelli
authors.forename: P
authors.initials: P
authors.lastname: Barbero
authors.forename: A
authors.initials: A
authors.lastname: Cucci
authors.forename: B
authors.initials: B
authors.lastname: Ferrero
authors.forename: A
authors.initials: A
authors.lastname: Ricci
authors.forename: G
authors.initials: G
authors.lastname: Contessa
authors.forename: S
authors.initials: S
authors.lastname: De Mercanti
authors.forename: P
authors.initials: P
authors.lastname: Ripellino
authors.forename: D
authors.initials: D
authors.lastname: Lapuma
authors.forename: E
authors.initials: E
authors.lastname: Viglietta
authors.forename: M
authors.initials: M
authors.lastname: Bergui
authors.forename: E
authors.initials: E
authors.lastname: Versino
authors.forename: M
authors.initials: M
authors.lastname: Clerico
mesh_terms: D000293:Adolescent; D000328:Adult; D057134:Antibodies, Neutralizing / Q000096:biosynthesis / Q000097:blood*; D003430:Cross-Sectional Studies; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D000068576:Interferon beta-1b; D016899:Interferon-beta / Q000008:administration & dosage* / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000188:drug therapy* / Q000276:immunology; D009500:Neutralization Tests; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D057134:Antibodies, Neutralizing; D000068576:Interferon beta-1b; D016899:Interferon-beta