General Information

Vaxchora contains live attenuated cholera bacteria that replicate in the gastrointestinal tract of the recipient.

Vaxchora is specifically approved for active immunization against disease caused by Vibrio cholerae serogroup O1. Vaxchora is approved for use in adults 18 through 64 years of age traveling to cholera-affected areas.

Vaxchora is supplied as a suspension for oral administration. After preparation, a single dose of Vaxchora is 100 mL. Vaxchora should be admiinistered a minimum of 10 days before potential exposure to cholera.

Clinical Results

FDA Approval

The FDA approval of Vaxchora was based on the following trials:

Vaxchora’s efficacy was demonstrated in a randomized, placebo-controlled human challenge study of 197 subjects in the U.S. from 18 through 45 years of age. Of the 197 subjects, 68 received Vaxchora and 66 received placebo. The subjects were challenged by oral ingestion of Vibrio cholerae, the bacterium that causes cholera. Vaxchora efficacy was 90% among those challenged 10 days after vaccination and 80% among those challenged three months after vaccination. The study included provisions for administration of antibiotics and fluid replacement in symptomatic participants. To prevent transmission of cholera into the community, the study included provisions for administration of antibiotics to subjects not developing symptoms.

Two placebo-controlled studies to assess the immune system’s response to the vaccine were also conducted in the U.S. and Australia in adults 18 through 64 years of age. In the 18 through 45 year age group, 93% of Vaxchora recipients produced antibodies indicative of protection against cholera. In the 46 through 64 years age group, 90% produced antibodies indicative of protection against cholera. The effectiveness of Vaxchora has not been established in persons living in cholera-affected areas.

Mechanism of Action

Vaxchora contains live attenuated cholera bacteria that replicate in the gastrointestinal tract of the recipient. Immune mechanisms conferring protection against cholera following receipt of Vaxchora have not been determined. However, rises in serum vibriocidal antibody 10 days after vaccination with Vaxchora were associated with protection in a human challenge study.