Safety, reactogenicity and immunogenicity of a recombinant protective antigen anthrax vaccine given to healthy adults.

Abstract

BACKGROUND:

Bacillus anthracis causes anthrax, a vaccine-preventable zoonotic disease that may follow intentional or unintentional exposure to its spores. Although an anthrax vaccine is currently licensed in the USA, better vaccines are desirable for both pre- and post-exposure prophylaxis.

METHODS:

Healthy adults, aged 18-40 years, received anthrax immunization with either licensed Anthrax Vaccine Adsorbed (AVA, BioThrax), or an experimental recombinant Protective Antigen vaccine (rPA) produced from an avirulent, non-spore-forming strain of B. anthracis at one of four doses (5, 25, 50 or 75 microg). Volunteers were followed for safety, reactogenicity, and immunogenicity.

RESULTS:

rPA vaccine was well tolerated with a low rate of local or systemic reactions. Although antibody responses were poor following unadjuvanted rPA administration, 89 and 100% of volunteers who received Alhydrogel-adjuvanted rPA given intramuscularly had four-fold increases by enzyme-linked immunosorbent and toxin neutralization assays, respectively. Peak antibody responses to adjuvanted rPA given intramuscularly were equivalent to AVA, given either intramuscularly or subcutaneously, when measured by either assay.

CONCLUSIONS:

This recombinant Protective Antigen anthrax vaccine, when given with the adjuvant Alhydrogel to healthy adults in two intramuscular injections four weeks apart, is very well-tolerated and highly immunogenic.

• Authors: James D Campbell, Kristin H Long Clement, Steven S Wasserman, Sarah Donegan, Lisa Chrisley, Karen L Kotloff
• Journal: Human vaccines (Hum Vaccin) 2007 Sep-Oct Vol. 3 Issue 5 Pg. 205-11 ISSN: 1554-8600 [Print] United States
• PMID: 17881903 (Publication Type: Clinical Trial, Phase I, Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Anthrax Vaccines
• Antibodies, Bacterial
• Antigens, Bacterial
• Recombinant Proteins

Topics

• Adolescent
• Adult
• Anthrax (immunology, prevention & control)
• Anthrax Vaccines (administration & dosage, adverse effects)
• Antibodies, Bacterial (blood)
• Antigens, Bacterial (genetics, immunology)
• Dose-Response Relationship, Drug
• Enzyme-Linked Immunosorbent Assay
• Female
• Humans
• Injections, Intramuscular
• Male
• Recombinant Proteins (immunology)