Botulinum neurotoxin vaccines: past, present, and future

Area of Science:

• Vaccinology
• Microbiology
• Biotechnology

Background:

• Early botulism prevention relied on formalin-inactivated toxoids, with pentavalent botulinum toxoid (PBT) used since 1965 for at-risk populations.
• PBT has a strong safety record, with over 20,000 doses administered and continued use in high-risk individuals.
• Recent advancements utilize recombinant DNA technology to develop next-generation botulism vaccines.

Purpose of the Study:

• To evaluate the safety and immunogenicity of a novel recombinant subunit vaccine against botulism.
• To assess the efficacy of a bivalent recombinant vaccine targeting botulinum neurotoxin (BoNT) serotypes A and B in human trials.

Main Methods:

• Development of second-generation vaccines using recombinant DNA technology.
• Creation of recombinant subunit vaccines incorporating receptor-binding domains of BoNT.
• Phase I clinical trial of a recombinant bivalent vaccine (rBV A/B) in human participants.

Main Results:

• Recombinant subunit vaccines have demonstrated safety and efficacy in animal models against multiple BoNT serotypes (A, B, C1, D, E, F).
• The rBV A/B vaccine was found to be safe and well-tolerated across all tested dosage levels in the phase I trial.
• The majority of human participants in the trial developed serotype-specific neutralizing antibodies.

Conclusions:

• Recombinant subunit vaccines represent a significant advancement in botulism prevention.
• The rBV A/B vaccine is a safe and immunogenic candidate for preventing botulism caused by BoNT serotypes A and B.
• Further clinical development of recombinant vaccines is warranted for broad-spectrum botulism protection.