Cross-neutralization capacity of immune serum from different dosage of Sabin inactivated poliovirus vaccine immunization against multiple individual polioviruses.

Objectives To study the neutralizing capacity of Sabin strain-inactivated poliovirus vaccine (sIPV) immune serum against different strains of poliovirus. Research design and methods A neutralization assay against ten individual virus strains was performed on serum collected from 250 infant participants, who randomly received three doses of investigational sIPV with high, medium, and low antigen content, conventional inactivated poliovirus vaccine (cIPV), and control sIPV, at 0, 1, and 2 months. This study was conducted between July 20, 2019, and January 10, 2020, and the study location was Pizhou city, Jiangsu province, China. Results Immune serum interacted with the 10 poliovirus strains in a dose-dependent manner. The seroconversion rates against all the tested poliovirus strains induced by the medium dose investigational sIPV, control cIPV, and control sIPV ranged from 91.3% to 100% (GMT 47.8-1303.2), 85.7% to 100% (GMT 95.2-514.0), and 82.6% to 100% (GMT 50.3-1481.2), respectively. Conclusion The investigational sIPV can induce good immunogenicity against the Sabin and Salk poliovirus strains, as well as the recently circulating poliovirus strains. Trial registration : The trial is registered at ClinicalTrials.gov (CT.gov identifier: NCT04618783).