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Typhoid Vi vaccine

International Vaccine Institute · FDA-approved active Biologic

The Typhoid Vi vaccine stimulates the immune system to produce antibodies and cellular immunity against Salmonella typhi by presenting the bacterial Vi polysaccharide capsular antigen.

The Typhoid Vi vaccine stimulates the immune system to produce antibodies and cellular immunity against Salmonella typhi by presenting the bacterial Vi polysaccharide capsular antigen. Used for Prevention of typhoid fever caused by Salmonella typhi in travelers and at-risk populations.

At a glance

Generic nameTyphoid Vi vaccine
Also known asTypherix
SponsorInternational Vaccine Institute
Drug classpolysaccharide vaccine
TargetSalmonella typhi Vi polysaccharide capsular antigen
ModalityBiologic
Therapeutic areaImmunology / Infectious Disease
PhaseFDA-approved

Mechanism of action

The vaccine contains purified Vi polysaccharide from the outer capsule of Salmonella typhi, which is recognized by B cells to generate protective antibodies and by T cells to establish cellular immunity. This immune response prevents infection when exposed to wild-type typhoid bacteria. The Vi antigen is a key virulence factor that protects the bacteria from complement-mediated killing, making it an effective immunogenic target.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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