title: Factors influencing the efficacy of two injections of a pandemic 2009 influenza A (H1N1) nonadjuvanted vaccine in systemic lupus erythematosus.
abstract: OBJECTIVE
  To assess the factors influencing the efficacy of 2 injections of a pandemic 2009 influenza A (H1N1) vaccine in patients with systemic lupus erythematosus (SLE).
  
  
  METHODS
  We conducted a single-center, observational prospective study of 111 patients who were vaccinated with a monovalent, inactivated, nonadjuvanted, split-virus vaccine during December 2009 and January 2010 and received a second dose of vaccine 3 weeks later. The antibody response was evaluated using the hemagglutination inhibition assay according to the guidelines recommended for the pandemic vaccine, consisting of 3 immunogenicity criteria (i.e., a seroprotection rate of 70%, a seroconversion rate of 40%, and a geometric mean ratio [GMR] of 2.5).
  
  
  RESULTS
  The 3 immunogenicity criteria were met on day 42 (seroprotection rate 80.0% [95% confidence interval (95% CI) 72.5-87.5%], seroconversion rate 71.8% [95% CI 63.4-80.2%], and GMR 10.3 [95% CI 2.9-14.2]), while only 2 criteria were met on day 21 (seroprotection rate 66.7% [95% CI 57.9-75.4%], seroconversion rate 60.4% [95% CI 51.3-69.5%], and GMR 8.5 [95% CI 3.2-12.0]). The vaccine was well tolerated. Disease activity, assessed by the Safety of Estrogens in Lupus Erythematosus National Assessment version of the SLE Disease Activity Index, the British Isles Lupus Assessment Group score, and the Systemic Lupus Activity Questionnaire, did not increase. In the multivariate analysis, vaccination failure was significantly associated with immunosuppressive treatment or a lymphocyte count of ≤ 1.0 × 10⁹/liter. The second injection significantly increased the immunogenicity in these subgroups, but not high enough to fulfill the seroprotection criterion in patients receiving immunosuppressive treatment.
  
  
  CONCLUSIONS
  Our findings indicate that the efficacy of the vaccine was impaired in patients who were receiving immunosuppressive drugs or who had lymphopenia. A second injection increased vaccine immunogenicity without reaching all efficacy criteria for a pandemic vaccine in patients receiving an immunosuppressive agent. These results open possibilities for improving anti-influenza vaccination in SLE.
authors.affiliation: Centre de Référence National pour les Lupus et le Syndrome des Antiphospholipides, Groupement Hospitalier Pitié-Salpêtrière, AP-HP, Université Pierre et Marie Curie, Université Paris 06, and INSERM UMR-S 945, Paris, France. alexis.mathian@psl.aphp.fr
authors.forename: A
authors.initials: A
authors.lastname: Mathian
authors.forename: H
authors.initials: H
authors.lastname: Devilliers
authors.forename: A
authors.initials: A
authors.lastname: Krivine
authors.forename: N
authors.initials: N
authors.lastname: Costedoat-Chalumeau
authors.forename: J
authors.initials: J
authors.lastname: Haroche
authors.forename: D Boutin-Le Thi
authors.initials: DB
authors.lastname: Huong
authors.forename: B
authors.initials: B
authors.lastname: Wechsler
authors.forename: B
authors.initials: B
authors.lastname: Hervier
authors.forename: M
authors.initials: M
authors.lastname: Miyara
authors.forename: N
authors.initials: N
authors.lastname: Morel
authors.forename: N
authors.initials: N
authors.lastname: Le Corre
authors.forename: L
authors.initials: L
authors.lastname: Arnaud
authors.forename: J C
authors.initials: JC
authors.lastname: Piette
authors.forename: L
authors.initials: L
authors.lastname: Musset
authors.forename: B
authors.initials: B
authors.lastname: Autran
authors.forename: F
authors.initials: F
authors.lastname: Rozenberg
authors.forename: Z
authors.initials: Z
authors.lastname: Amoura
mesh_terms: D000328:Adult; D000917:Antibody Formation; D005260:Female; D006801:Humans; D016867:Immunocompromised Host / Q000276:immunology*; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000009:adverse effects / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control*; D008180:Lupus Erythematosus, Systemic / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D007252:Influenza Vaccines