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YF vaccine (live)

Sanofi · Phase 3 active Biologic

YF vaccine (live) is a live attenuated yellow fever virus vaccine that stimulates both humoral and cellular immune responses to provide protection against yellow fever infection.

YF vaccine (live) is a live attenuated yellow fever virus vaccine that stimulates both humoral and cellular immune responses to provide protection against yellow fever infection. Used for Prevention of yellow fever in endemic regions and travelers to yellow fever-endemic areas.

At a glance

Generic nameYF vaccine (live)
Also known asYF-VAX vaccine, YF-VAX
SponsorSanofi
Drug classLive attenuated vaccine
ModalityBiologic
Therapeutic areaImmunology / Infectious Disease
PhasePhase 3

Mechanism of action

The vaccine contains a weakened strain of yellow fever virus (17D strain) that replicates in vaccinated individuals but does not cause disease in immunocompetent hosts. This replication triggers robust antibody production and T-cell mediated immunity, conferring long-lasting protection against natural yellow fever virus infection. A single dose typically provides lifelong immunity in most recipients.

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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