The current anthrax vaccine adsorbed (AVA) vaccine is given in six doses -- at zero, two and four weeks then again at six, 12 and 18 months -- below the skin, or subcutaneously, with annual boosters.
If people are given three shots of Emergent's BioThrax in an arm muscle, they also had the same immune response as those who got four standard injections under the skin. Also, intramuscular injection led to less swelling and redness than skin shots, the study by the Centers for Disease Control and Prevention said.
Researchers at the CDC studied 1,005 people and followed five groups that got either three or four doses of BioThrax, under the skin or into the muscle, over six weeks. The first four standard shots are normally followed up with additional injections at one year and then 18 months.
After seven months, all the groups showed a comparable immune response. The CDC's Advisory Committee on Immunization Practice is planning to revise its recommendations on use of BioThrax vaccine now. The study that will be published in the Journal of the American Medical Association.
