| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 2409486 | Vaccine | 2006 | 7 Pages |
The antibody profile during and after the six-dose primary vaccination series with anthrax vaccine adsorbed (AVA, Biothrax™) was characterized in 86 human volunteers. Ninety-three percent of recipients developed IgG antibodies to Bacillus anthracis protective antigen (PA) after two doses, and 100% were seropositive after dose #3. Geometric mean concentrations (GMC) of IgG to PA measured before and after each dose were significantly lower after injection #3 (peak GMC = 146.65 μg/mL, trough GMC = 15.16 μg/mL) than after injections #4 (peak GMC = 430.46 μg/mL, trough GMC = 94.57 μg/mL), #5 (peak GMC = 415.05 μg/mL, trough GMC = 81.94 μg/mL), or #6 (peak GMC = 401.16μg/mL, trough GMC = 96.19 μg/mL) (p ≤ 0.0001 for each); but not between injections #4 and #5, #5 and #6, or #4 and #6 (p ≥ 0.7923 for each). Decay rates for IgG to PA were significantly faster after injection #3 (half life [T1/2] = 39.21 days) than after injections #4 (T1/2 = 72.03 days), #5 (T1/2 = 70.14 days), and #6 (T1/2 = 74.59 days) (p ≤ 0.0282 for each). Toxin neutralizing assay (TNA) antibody patterns generally paralleled those for IgG to PA. The 6-month dose in the AVA primary series appears to be critical in sustaining IgG to PA concentrations in a substantial proportion of recipients.
