Serological responses to Anthrax Vaccine Precipitated (AVP) increase with time interval between booster doses

Crown Copyright © 2022. Published by Elsevier Ltd. All rights reserved..

We undertook a Phase 4 clinical trial to assess the effect of time interval between booster doses on serological responses to AVP. The primary objective was to evaluate responses to a single booster dose in two groups of healthy adults who had previously received a complete 4-dose primary course. Group A had received doses on schedule while Group B had not had one for ≥2 years. Secondary objectives were to evaluate the safety and tolerability of AVP booster doses, and to gain information on correlates of protection to aid future anthrax vaccine development. Blood samples were taken on Day 1 before dosing, and on Days 8, 15, 29 and 120, to measure Toxin Neutralisation Assay (TNA) NF50 values and concentrations of IgG antibodies against Protective Antigen (PA), Lethal Factor (LF) and Edema Factor (EF) by ELISA. For each serological parameter, fold changes from baseline following the trial AVP dose were greater in Group B than Group A at every time-point studied. Peak responses correlated positively with time since last AVP dose (highest values being observed after intervals of ≥10 years), and negatively with number of previous doses (highest values occurring in individuals who had received a primary course only). In 2017, having reviewed these results, the Joint Committee on Vaccination and Immunisation (JCVI) updated UK anthrax vaccination guidelines, extending the interval between routine AVP boosters from one to 10 years. Booster doses of AVP induce significant IgG responses against the three anthrax toxin components, particularly PA and LF. Similarly high responses were observed in TNA, a recognised surrogate for anthrax vaccine efficacy. Analysis of the 596 TNA results showed that anti-PA and anti-LF IgG make substantial independent contributions to neutralisation of anthrax lethal toxin. AVP may therefore have advantages over anthrax vaccines that depend on generating immunity to PA alone.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:40

Enthalten in:

Vaccine - 40(2022), 42 vom: 06. Okt., Seite 6163-6178

Sprache:

Englisch

Beteiligte Personen:

Dyson, E Hugh [VerfasserIn]
Simpson, Andrew J H [VerfasserIn]
Gwyther, Robert J [VerfasserIn]
Cuthbertson, Hannah [VerfasserIn]
Patient, Dawn H [VerfasserIn]
Matheson, Mary [VerfasserIn]
Gregg, Anya [VerfasserIn]
Hepburn, Matthew J [VerfasserIn]
Hallis, Bassam [VerfasserIn]
Williamson, E Diane [VerfasserIn]

Links:

Volltext

Themen:

AVP
Anthrax Vaccines
Anthrax vaccine
Antibodies, Bacterial
Antigens, Bacterial
Booster dose
Clinical Trial, Phase IV
Clinical trial
Immunoglobulin G
Journal Article
Research Support, Non-U.S. Gov't
Serological responses
TNA

Anmerkungen:

Date Completed 04.10.2022

Date Revised 23.11.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.vaccine.2022.08.052

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM346694183