Highlight
– First-in-human, observer-masked phase 1 trial shows novel type 1 and type 3 oral poliovirus vaccines (nOPV1, nOPV3) are well tolerated in healthy adults.
– Immunogenicity (homotypic neutralising antibody responses) after a single dose was high (86–100% seroconversion for nOPV; 86–93% for mOPV); seroprotection at 28 days reached 100%.
– Faecal viral shedding kinetics and peak detection by PCR were similar between nOPV and Sabin monovalent OPV (mOPV); peak shedding reached 100% by PCR on day 8 in IPV recipients.
– Results support advancement of nOPV1 and nOPV3 into phase 2 trials, while further evaluation in children, immunocompromised hosts, and population-level genetic stability remains essential.
