Khouri JM, et al. - Healthy volunteers who had been previously immunized with investigational pentavalent botulinum toxoid were examined in an open-label, uncontrolled study, to assess the safety and immunogenicity of investigational recombinant botulinum vaccine for botulinum neurotoxin (BoNT) serotypes A and B (rBV A/B). Study participants who wished to do so could donate their hyperimmune plasma for production of Human Botulism Immune Globulin Intravenous (BIG-IV, BabyBIG). Findings demonstrated the safety, good tolerability as well as immunogenicity of a single 0.5 mL dose of rBV A/B in participants previously immunized with pentavalent botulinum toxoid. The potential future use of rBV A/B vaccination to provide occupational protection to botulism laboratory workers was supported by its tolerability and immunogenicity characteristics in individuals with existing BoNT immunity. Almost all study participants donated hyperimmune plasma for production of BIG-IV.