M01ZH09

M01ZH09 is a live-attenuated oral typhoid vaccine candidate developed by the University of Oxford's Oxford Vaccine Group. It is derived from the *Salmonella enterica* serovar Typhi strain Ty2 and features two specific, independently attenuating genetic deletions: the *aroC* gene, which disrupts the aromatic amino acid biosynthetic pathway, and the *ssaV* gene, which encodes a structural component of the Salmonella Pathogenicity Island 2 (SPI-2) Type III secretion system. These modifications are designed to render the strain replication-deficient and prevent systemic spread while maintaining macrophage infectivity and the ability to induce mucosal and systemic immune responses. Although clinical trials demonstrated that the vaccine was well-tolerated and immunogenic after a single oral dose, it failed to provide significant protective efficacy in a controlled human infection model (CHIM) against virulent *S. Typhi* challenge.

Brand names

Typhella

Other names

Salmonella enterica serovar Typhi ZH9Ty2 aroC- ssaV- ZH9Ty-2 aroC- ssaV- ZH9Ty 2 aroC- ssaV- ZH9Typhoid vaccine (live, oral, ZH9)