Anthrax vaccine

Kathryn Dzintars, PharmD, BCPS, Paul A. Pham, Pharm.D.
Pediatric Dosing Author: Alice Jenh Hsu, PharmD, BCPS, AQ-ID


Anthrax vaccine (AVA, BIOTHRAX), killed vaccine made from the cell-free filtrate of the nonencapsulated, attenuated strain of B. anthracis culture that contains no dead or live bacteria (note: a live attenuated vaccine was manufactured in the former USSR, but no longer available).



  • Routine vaccination with anthrax vaccine indications for persons engaged in:
  1. Work involving production quantities or concentrations of B. anthracis cultures.
  2. Activities with a high potential for anthrax aerosol production
  • Routine anthrax vaccine NOT recommended:
    • Laboratory personnel using standard Biosafety Level 2 practices in the routine processing of clinical samples are not at increased risk for exposure to B. anthracis spores.
  • Veterinarians in the U.S. not recommended because of the low incidence of animal cases.
    • Vaccination may be considered in high-risk persons handling potentially infected animals in areas with a high incidence of anthrax cases.
  • For bioterrorism preparedness (e.g., first responders, federal responders, medical practitioners, and private citizens).
    • The Working Group on Civilian Biodefense does recommend vaccination of exposed persons following a biological attack in conjunction with abx administration for 60 days following exposure.
  • ACIP recommends that if antimicrobial prophylaxis is administered in combination with post-exposure vaccination, it is prudent to continue antibiotics until 7-14 days after the third vaccine dose.


  • Post-exposure prophylaxis: AVA given as a sole agent was not effective in one primate study. AVA was effective if abx with activity against anthrax was given concurrently. The duration of post-exposure antimicrobial prophylaxis should be 60 days if used alone for PEP of unvaccinated exposed persons.
    • Approved for indication by FDA in November 2015.
  • Department of Defense has mandated some U.S. military active- and reserve-duty personnel receive pre-exposure (vaccine) prophylaxis as an adjunct to prolonged post-exposure antibiotic prophylaxis.
  • Pre-exposure vaccination of some persons deemed to be in high-risk groups should also be considered.


brand name








Anthrax Vaccine Adsorbed

Bioport Corp, Lansing, Michigan.



10 doses/ vial

$900 per vial

*Prices represent cost per unit specified, are representative of "Average Wholesale Price" (AWP).
^Dosage is indicated in mg unless otherwise noted.




  • Pre-exposure prophylaxis: 0.5 mL IM x 3 doses at 0, 6, and 12.
  • Post-exposure prophylaxis: 0.5 mL SQ x 3 doses, 0, 2 and 4 weeks after exposure.
    • Combine with antimicrobial therapy and possibly antibody administration (see anthrax prophylaxis modules for details).
  • Note: doses can be given IM or SQ, but IM recommended for pre-exposure and SQ for post-exposure prophylaxis.



  • 0.5 mL IM at 6 and 12 months after completion of the primary series.
  • Yearly booster dose (0.5mL IM) required to maintain immunity.


Not approved or studied in children (< 18 yrs old). The regimen of 3 doses at 0, 2 and 4 weeks after exposure (along with antimicrobial prophylaxis) available under IND protocol (#10061) if public health authorities determine an exposure event has occurred and use if justified.



No long-term sequelae reported

  • Generally well tolerated


  • Injection site nodule: most frequently reported local reaction and more common in women for unexplained reasons (60% vs 30% in men).
  • About 4% develop extensive erythema and swelling that may extend to the antecubital fossa --often misdiagnosed as bacterial cellulitis.


  • Headache (0.4%)
  • Myalgia or arthralgia
  • Headache
  • Fatigue


  • Anaphylaxis


  • No known drug interaction


  • History of an anaphylactic reaction to the vaccine. Previous anthrax infection (re: more severe adverse events among recipients with a vaccine history of anthrax).


The relationship between immunity and quantitative antibody levels has not been evaluated. Onset of protection: antibody titer increased 3-4x approximately 7d after the second dose (3-4 wks from first dose). However, clear minimum therapeutic antibody response has not been established but appears to be sufficient to prevent the development of disease once antibiotics were discontinued. An estimated 83% of human vaccinees develop a vaccine-induced immune response after two doses of the vaccine and >95% develop a four-fold rise in antibody titer after three doses.


  • Effective in a placebo-controlled human trial against cutaneous anthrax. Primate models showed that antibiotic prevented inhalation anthrax, but were not protected from re-challenge.
  • However, all animals given vaccine PLUS antibiotic were protected with re-challenge[8].


  • As post-exposure prophylaxis, vaccine indicated only for risk of inhalation anthrax but prevents cutaneous anthrax as well.
    • AVA available since 1970.
  • Post-exposure prophylaxis with 60 days of antibiotics remains the cornerstone of management but since 2015, now incorporates the AVA vaccine.
    • Only people who should not get the vaccine are those with history of serious reaction to previous dose of AVA vaccine.
  • The risk for persons who come in contact in the workplace with imported animal hides, furs, bone meal, wool, animal hair, or bristles has been reduced by changes in industry standards and import restrictions.
    • Routine preexposure vaccination is recommended only for persons in this group for whom these standards and restrictions are insufficient to prevent exposure to anthrax spores.
  • Safety in Pregnancy: Category D. Earlier unpublished study of infants born to women in the U.S. military service worldwide in 1998 and 1999 suggest that the vaccine may be linked with an increase in the number of birth defects. However, a published study found no effect on pregnancy or adverse birth outcomes in a cohort involving 4092 women[7].
  • Potentially exposed persons should be observed for signs of febrile illness.

Basis for recommendation

  1. Hendricks KA, Wright ME, Shadomy SV, et al. Centers for disease control and prevention expert panel meetings on prevention and treatment of anthrax in adults. Emerg Infect Dis. 2014;20(2).  [PMID:24447897]

    Comment: An expert panel that has led to current recommendations updating antimicrobial postexposure prophylaxis and antimicrobial and antitoxin treatment options

  2. Wright JG, Quinn CP, Shadomy S, et al. Use of anthrax vaccine in the United States: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2009. MMWR Recomm Rep. 2010;59(RR-6):1-30.  [PMID:20651644]

    Comment: Current CDC/ACIP recommendations.

  3. Centers for Disease Control and Prevention (CDC). Use of anthrax vaccine in response to terrorism: supplemental recommendations of the Advisory Committee on Immunization Practices. MMWR Morb Mortal Wkly Rep. 2002;51(45):1024-6.  [PMID:12458919]

    Comment: ACIP recommendations

  4. Advisory Committee on Immunization Practices. Use of anthrax vaccine in the United States. MMWR Recomm Rep. 2000;49(RR-15):1-20.  [PMID:11145529]

    Comment: ACIP recommendations

  5. Vaccine Information Statement, Anthrax VIS.… (accessed 2/21/2019)

    Comment: This statement handles both pre- and post-exposure prophylaxis. The vaccine has not been studied in ages < 18 years. If used in children, will need to be done as part of IND program.


  1. Hopkins RJ, Howard C, Hunter-Stitt E, et al. Phase 3 trial evaluating the immunogenicity and safety of a three-dose BioThrax® regimen for post-exposure prophylaxis in healthy adults. Vaccine. 2014;32(19):2217-24.  [PMID:24613523]

    Comment: This trial helped establish the pre-determined immunogenicity efficacy of the 3-dose SQ approach of AVA.

  2. Wiesen AR, Littell CT. Relationship between prepregnancy anthrax vaccination and pregnancy and birth outcomes among US Army women. JAMA. 2002;287(12):1556-60.  [PMID:11911758]
  3. Friedlander AM, Welkos SL, Pitt ML, et al. Postexposure prophylaxis against experimental inhalation anthrax. J Infect Dis. 1993;167(5):1239-43.  [PMID:8486963]
  4. Clinical Framework and Medical Countermeasure Use Durin an Anthrax Mass-Casualty Incident. MMWR 2015;64(4).… (accessed 2/21/2109)

    Comment: The guideline emphasizes antimicrobial use for mass-causality, acutely ill patients. Vaccine not recommended here.

Anthrax vaccine is a sample topic from the Johns Hopkins ABX Guide.

To view other topics, please or .

Official website of the Johns Hopkins Antibiotic (ABX), HIV, Diabetes, and Psychiatry Guides, powered by Unbound Medicine. Johns Hopkins Guide App for iOS, iPhone, iPad, and Android included. .

Last updated: March 5, 2019