GSK4429016A

**GSK4429016A (Kleb4V)** is a tetravalent bioconjugate vaccine developed by LimmaTech Biologics and GSK to prevent infections caused by *Klebsiella pneumoniae*, a major antibiotic-resistant pathogen. It contains O-antigen polysaccharides from the four most predominant serotypes (O1v1, O2a, O2afg, O3b) conjugated to carrier proteins, formulated with or without the AS03 adjuvant, and administered intramuscularly. In a phase I/II trial (NCT04959344) involving 166 healthy adults (18-70 years), it demonstrated good tolerability with mostly mild to moderate adverse events and immunogenicity across all serotypes, with IgG responses persisting six months post-vaccination; AS03-adjuvanted versions showed superior responses for three serotypes, though O3b was weaker.[1][2][3][5]

Brand names

Kleb4VKleb-4VKleb 4V

Other names

Klebsiella pneumoniae tetravalent bioconjugate vaccine