The shelf-life of AVA is reported to be three years when stored between 2 °C and 8 °C (36 °F and 46 °F) and never frozen. History
Initial research and development (1954-1970)
The vaccine efficacy of AVA in humans was initially established by Philip S. Brachman of the United States Public Health Service (USPHS) in a controlled study undertaken between 1954 and 1959. The study field sites were four wool-sorting mills in the northeastern United States where employees were sometimes exposed to anthrax spores in the course of their work. Over the five years, 379 vaccinees were compared against 414 unvaccinated control subjects. There were 23 cases among controls (5 of them inhalation anthrax) compared with 3 cases among vaccinated (0 inhalation cases). The vaccine was judged to have a 92.5% vaccine efficacy against all types of anthrax experienced. Subsequently, there were no controlled clinical trials in humans of the efficacy of AVA due to the rarity of the condition (especially in the inhalational form) in humans and the ethical inadmissibility of conducting dangerous challenge studies in human subjects. Supportive animal challenge studies were done, however, showing that unvaccinated animals uniformly die whereas vaccinated animals are protected. About 95% of rhesus monkeys (62 of 65) survived challenge, as did 97% of rabbits (114 of 117). Guinea pigs (which are a poorer model for human anthrax than are monkeys or rabbits) showed a 22% protection (19 of 88).
The academy considered more than a dozen studies using various scientific designs, and heard personally from many concerned US military service members. Development of a replacement vaccine
While effective in protecting against anthrax, the licensed vaccine schedule is not very efficient, involving a cumbersome five (previously six) dose injection series. Typically, five injections are given over a period of 18 months in order to induce a protective immune system response. In addition, in 2004 the US Department of Health and Human Services contracted with Vaxgen Inc. to supply up to 75 million doses of a recombinant anthrax vaccine, for $877 million. To be acceptable to HHS, this vaccine was to be protective against anthrax in three doses or less. On December 19, 2006, HHS voided the contract, because of stability problems with the vaccine, and a failure to start a Phase 2 clinical trial on time. In May 2008, Emergent Biosolutions, the Maryland-based successor to BioPort, both controlled by former Lebanese banker Faud el Hibri, acquired rights to Vaxgens patents and processes.On 30 October 2012, the US National Institute of Allergy and Infectious Diseases agreed to provide $6.5 million to the United Kingdoms Health Protection Agency for initial work on a potential future anthrax vaccine that could be delivered through the nasal passage instead of via a needle. The HPA has long produced the UKs AVP anthrax vaccine. Research is being continuously done to develop and test new improved candidate anthrax vaccines.