title: Teriflunomide effect on immune response to influenza vaccine in patients with multiple sclerosis.
abstract: OBJECTIVE
  To investigate the effect of teriflunomide on the efficacy and safety of seasonal influenza vaccine.
  
  
  METHODS
  The 2011/2012 seasonal influenza vaccine (containing H1N1, H3N2, and B strains) was administered to patients with relapsing forms of multiple sclerosis (RMS) treated for ≥6 months with teriflunomide 7 mg (n = 41) or 14 mg (n = 41), or interferon-β-1 (IFN-β-1; n = 46). The primary endpoint was the proportion of patients with influenza strain-specific antibody titers ≥40, 28 days postvaccination.
  
  
  RESULTS
  More than 90% of patients achieved postvaccination antibody titers ≥40 for H1N1 and B in all groups. For H3N2, titers ≥40 were achieved in ≥90% of patients in the 7 mg and IFN-β-1 groups, and in 77% of the 14-mg group, respectively. A high proportion of patients already had detectable antibodies for each influenza strain at baseline. Geometric mean titer ratios (post/prevaccination) were ≥2.5 for all groups and strains, except for H1N1 in the 14-mg group (2.3). The proportion of patients with a prevaccination titer <40 achieving seroprotection was ≥61% across the 3 treatment groups and 3 influenza strains. However, fewer patients in the 14-mg than the 7-mg or IFN-β-1 groups exhibited seroprotection to H3N2 (61% vs. 78% and 82%, respectively).
  
  
  CONCLUSIONS
  Teriflunomide-treated patients generally mounted effective immune responses to seasonal influenza vaccination, consistent with preservation of protective immune responses.
  
  
  METHODS
  This study provides Class II evidence that teriflunomide generally does not adversely impact the ability of patients with RMS to mount immune responses to influenza vaccination.
authors.affiliation: McGill University, Montreal, Quebec, Canada. amit.bar-or@mcgill.ca
authors.forename: Amit
authors.initials: A
authors.lastname: Bar-Or
authors.forename: Mark S
authors.initials: MS
authors.lastname: Freedman
authors.forename: Marcelo
authors.initials: M
authors.lastname: Kremenchutzky
authors.forename: Françoise
authors.initials: F
authors.lastname: Menguy-Vacheron
authors.forename: Deborah
authors.initials: D
authors.lastname: Bauer
authors.forename: Stefan
authors.initials: S
authors.lastname: Jodl
authors.forename: Philippe
authors.initials: P
authors.lastname: Truffinet
authors.forename: Myriam
authors.initials: M
authors.lastname: Benamor
authors.forename: Scott
authors.initials: S
authors.lastname: Chambers
authors.forename: Paul W
authors.initials: PW
authors.lastname: O'Connor
mesh_terms: D000328:Adult; D000914:Antibodies, Viral / Q000096:biosynthesis*; D003437:Crotonates / Q000276:immunology* / Q000627:therapeutic use*; D004347:Drug Interactions / Q000276:immunology; D005260:Female; D006801:Humans; D006885:Hydroxybutyrates; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D053122:Influenza A Virus, H3N2 Subtype / Q000276:immunology; D007252:Influenza Vaccines / Q000008:administration & dosage* / Q000276:immunology / Q000627:therapeutic use; D038622:Internationality; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000188:drug therapy* / Q000276:immunology* / Q000821:virology; D009570:Nitriles; D014052:Toluidines / Q000276:immunology* / Q000627:therapeutic use*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D003437:Crotonates; D006885:Hydroxybutyrates; D007252:Influenza Vaccines; D009570:Nitriles; D014052:Toluidines; C527525:teriflunomide