Clinical Trial: Residual Anti-pneumococcal Immunity After Pneumococcal Immunization in ANCA-associated Vasculitis

Study Status: Completed
Recruit Status: Completed
Study Type: Observational

Official Title: Residual Anti-pneumococcal Immunity After Pneumococcal Immunization in ANCA-associated Vasculitis. PneumoVas Pilot 1

Brief Summary: Descriptive study of the residual anti-pneumococcal immunity in patients with Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) who have previously gone through pneumococcal immunization.

Detailed Summary: The purpose of this study is to determine, through serotype-specific enzyme linked immunosorbent assay (ELISA) and opsonophagocytosis (OPA) titres whether AAV patients who have gone through pneumococcal vaccination are protected against invasive pneumococcal diseases (IPD).
Sponsor: Assistance Publique - Hôpitaux de Paris

Current Primary Outcome: Residual anti-pneumococcal immunity after pneumococcal immunization. [ Time Frame: visit V0 (day 0) ]

Proportion of patients at baseline (V0) with ≥1 µg/mL ELISA immunoglobulins G (IgG) antibody titers to at least 6 of the 10 shared serotypes (i.e. 3, 4, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F) included both in the 13-valent conjugate pneumococcal vaccine (PCV13) and in the 23-valent non-conjugate pneumococcal vaccine (PPV23)


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • To assess serotype 3, 4, 6B, 7F, 9V, 14, 18C, 19 A, 19F, 23F, 10A and 12F-specific residual immunity after vaccination [ Time Frame: visit V0 (day 0), visit V-1 (pre immunization) ]
    ELISA specific antibody titres to serotype 3, 4, 6B, 7F, 9V, 14, 18C, 19 A, 19F, 23F (included both in PCV13 and PPV23), 10A and 12F (specific to PPV23)
  • For each of the following serotypes (3, 4, 6B, 7F, 9V, 14, 18C, 19A, 19F, 23F), to assess among ELISA-protected patients (i.e. with a ≥1 µg/mL ELISA IgG antibody titer) the proportion who also show in vitro opsonophagocytic antibody activity [ Time Frame: visit V0 (day 0) ]

    Descriptive analysis:

    a/ For each of the following serotypes (3, 4, 6B, 7F, 9V, 14, 18C, 19A, 19F, 23F), opsonophagocytosis (OPA) titers will be measured in ELISA-protected patients at V0. Opsonophagocytic antibody activity is considered positive if the antibody titer is above a serotype-specific predefined threshold.

    B/ The proportion of overall OPA-protected patients (meaning ≥ 50% of OPA positive serotypes )

  • For patients for whom pre-vaccinal serum is available (via the PHENOVASC bank), to assess the impact of immunization on serotype-specific ELISA antibody titer and OPA activity. [ Time Frame: visit V-1 (pre immunization) ; visit V0 (day 0) ]

    For patients already included in the PHENOVASC study (V-1) ≤6 months before receiving pneumococcal immunization, anti-pneumococcal immunity will be assessed for serotype 3 , 4 , 6B, 7F, 9V, 14 , 18C, 19A , 19F , 23F, 10A and 12F (with ELISA only for the two latter).

    For each serotype:

    In ELISA, we will describe the proportion of responding patients (i.e. with a two-fold increase from V-1 to VO and a ≥1 μg/ml titre at V0.

    In VO ELISA-responding patients, OPA titers will be measured. An opsonophagocytic antibody activity is considered positive if the antibody titer shows a four-fold increase from V-1 to V0 and is above a serotype-specific predefined threshold.

  • Composite Outcome Measures - To identify epidemiologic, clinic and biologic predictive factors that may influence vaccine-induced immune response. [ Time Frame: visit V-1 (pre immunization) ; visit V0 (day 0) ]
    Analysis of epidemiological, clinical and biological data collected during follow-up: age, sex, history of immunosuppressive therapy, time since previous PPV23 injection, number of previous PPV23 immunizations, AAV activity and severity according to Birmingham Vasculitis Activity Score and Vasculitis Damage Index, results of biological analyses


Original Secondary Outcome: Same as current

Information By: Assistance Publique - Hôpitaux de Paris

Dates:
Date Received: May 12, 2015
Date Started: September 2015
Date Completion:
Last Updated: August 18, 2016
Last Verified: August 2016