Results of Emergent BioSolutions Phase 1a Study on Adjuvanted BioThrax Anthrax Vaccine Published in the Journal Vaccine

Emergent BioSolutions Inc. EBS announced today that results from a Phase 1a clinical trial evaluating an investigational anthrax vaccine, Anthrax Vaccine Adsorbed with CPG 7909 Adjuvant mixed at bedside, have been published in Vaccine, a leading medical journal on vaccines and immunology. In the study, which enrolled 69 subjects, the addition of the CPG 7909 adjuvant to BioThrax, the only FDA-licensed anthrax vaccine, accelerated and enhanced the immune response to the vaccine in healthy volunteers. Trial subjects received three doses of either: (1) BioThrax alone, (2) 1 mg of CPG 7909 alone or (3) BioThrax plus 1 mg of CPG 7909, all given intramuscularly on study days 0, 14, and 28. Data from the trial show that BioThrax plus CPG 7909 generated peak antibody responses that were 6-fold higher than those generated by BioThrax alone (232 μg/ml with BioThrax alone; 1465 μg/ml with BioThrax plus CPG 7909). BioThrax plus CPG 7909 also accelerated the time to reach the peak immune response seen following BioThrax vaccination by three weeks. Both of these findings were statistically significant (P<0.001). Early immune responses are important due to the rapid disease progression of anthrax.