The Development of a New Generation of Cholera Vaccines

Michael Lebens of the University of Gothenburg Institute for Vaccine Research in Sweden proposes to develop a new oral cholera vaccine using a single cholera strain that expresses antigens for both the Inaba and Ogawa serotypes and produces cholera toxin subunits that act as an adjuvant to stimulate mucosal immune activity. In this project's Phase I research, Lebens and his team successfully generated potential vaccine candidate strains that express both Ogawa and Inaba type antigens simultaneously. They also demonstrated in an animal model that oral immunization with these bacteria in a killed formulation elicited immune responses similar to those obtained by vaccination with currently licensed oral killed whole-cell cholera vaccines. In Phase II, he will further improve these strains by inducing them to express an accompanying adjuvant and conduct immunogenicity analyses and other work to prepare for a Phase I trial.