title: Vaccination against influenza in patients with rheumatoid arthritis: the effect of rituximab on the humoral response.
abstract: OBJECTIVE
  To assess the effect of rituximab on the efficacy and safety of influenza virus vaccine in patients with rheumatoid arthritis (RA).
  
  
  METHODS
  The study group comprised patients with RA treated with conventional disease-modifying drugs with or without rituximab. Split-virion inactivated vaccine containing 15 microg haemagglutinin/dose of B/Shanghai/361/02 (SHAN), A/New Caledonian/20/99 (NC) (H1N1) and A/California/7/04 (CAL) (H3N2) was used. Disease activity was assessed by the number of tender and swollen joints, duration of morning stiffness and evaluation of pain on the day of vaccination and 4 weeks later. CD19-positive cell levels were assessed in rituximab-treated patients. Haemagglutination inhibition (HI) antibodies were tested and response was defined as a greater than fourfold rise 4 weeks after vaccination or seroconversion in patients with a non-protective baseline level of antibodies (<1/40). Geometric mean titres (GMT) were calculated in all subjects.
  
  
  RESULTS
  The participants were divided into three groups: RA (n = 29, aged 64 (12) years), rituximab-treated RA (n = 14, aged 53 (15) years) and healthy controls (n = 21, aged 58 (15) years). All baseline protective levels of HI antibodies and GMT were similar. Four weeks after vaccination, there was a significant increase in GMT for NC and CAL antigens in all subjects, but not for the SHAN antigen in the rituximab group. In rituximab-treated patients, the percentage of responders was low for all three antigens tested, achieving statistical significance for the CAL antigen. Measures of disease activity remained unchanged.
  
  
  CONCLUSIONS
  Influenza virus vaccine generated a humoral response in all study patients with RA and controls. Although the response was significantly lower among rituximab-treated patients, treatment with rituximab does not preclude administration of vaccination against influenza.
authors.affiliation: Department of Rheumatology, Tel Aviv Sourasky Medical Centre, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 64239, Israel.
authors.forename: S
authors.initials: S
authors.lastname: Oren
authors.forename: M
authors.initials: M
authors.lastname: Mandelboim
authors.forename: Y
authors.initials: Y
authors.lastname: Braun-Moscovici
authors.forename: D
authors.initials: D
authors.lastname: Paran
authors.forename: J
authors.initials: J
authors.lastname: Ablin
authors.forename: I
authors.initials: I
authors.lastname: Litinsky
authors.forename: D
authors.initials: D
authors.lastname: Comaneshter
authors.forename: D
authors.initials: D
authors.lastname: Levartovsky
authors.forename: E
authors.initials: E
authors.lastname: Mendelson
authors.forename: R
authors.initials: R
authors.lastname: Azar
authors.forename: I
authors.initials: I
authors.lastname: Wigler
authors.forename: A
authors.initials: A
authors.lastname: Balbir-Gurman
authors.forename: D
authors.initials: D
authors.lastname: Caspi
authors.forename: O
authors.initials: O
authors.lastname: Elkayam
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000494:pharmacology* / Q000627:therapeutic use; D058846:Antibodies, Monoclonal, Murine-Derived; D000914:Antibodies, Viral / Q000096:biosynthesis; D018501:Antirheumatic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000188:drug therapy / Q000276:immunology*; D005260:Female; D006385:Hemagglutination Inhibition Tests / Q000379:methods; D006801:Humans; D009980:Influenza A virus / Q000276:immunology; D009981:Influenza B virus / Q000276:immunology; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D000069283:Rituximab; D012720:Severity of Illness Index; D014611:Vaccination
chemical_list: D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D000914:Antibodies, Viral; D018501:Antirheumatic Agents; D007252:Influenza Vaccines; D000069283:Rituximab