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BCG Sii

University of Oxford · Phase 3 active Small molecule

BCG Sii is a live attenuated Mycobacterium bovis BCG vaccine strain designed to stimulate innate and adaptive immune responses.

BCG Sii is a live attenuated Mycobacterium bovis BCG vaccine strain designed to stimulate innate and adaptive immune responses. Used for COVID-19 prevention or therapeutic immunization (investigational).

At a glance

Generic nameBCG Sii
Also known asBacille Calmette-Guérin Serum Institute of India
SponsorUniversity of Oxford
Drug classLive attenuated vaccine
ModalitySmall molecule
Therapeutic areaImmunology
PhasePhase 3

Mechanism of action

BCG (Bacillus Calmette-Guérin) is a live attenuated mycobacterial vaccine that activates both innate immunity through pattern recognition receptors and adaptive immunity through T-cell and B-cell responses. The Sii strain variant from the Serum Institute of India is being investigated for enhanced immunogenicity. In phase 3 development, it is being studied for potential therapeutic applications beyond traditional tuberculosis prevention.

Approved indications

Common side effects

Key clinical trials

Primary sources

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