EraPolio Mechanism of Action

Pharmacology: Clinical Studies: This product has completed phase Ⅰ, phase Ⅱ, phase Ⅲ pivotal clinical trials, and phase Ⅲ sIPV & OPV sequential vaccination clinical trials, as well as the cross-neutralization study based on the serum collected in the phase Ⅱ clinical trial. (See Table 1.)

Click on icon to see table/diagram/image

Primary Vaccination: In the phase III pivotal clinical trial, the immunogenicity endpoint evaluation and non-inferiority analysis were conducted based on the per-protocol set (PPS). A total of 553 subjects in the experimental group and 652 subjects in the control group were included in the PPS. The clinical trial results of FAS and PPS are consistent.
The immunogenicity evaluation endpoints include the seroconversion rates and geometric mean titer (GMT). The seroconversion is defined as a change from seronegative (<1:8) to seropositive (≥1:8) or a 4-fold increase from baseline titers if seropositive. The serum antibody assay was performed using the World Health Organization standard method, i.e. micro-neutralization test method. The immunogenicity results of the primary vaccination are shown in Table 2 and Table 3. (See Tables 2 and 3.)

Click on icon to see table/diagram/image


Click on icon to see table/diagram/image

Booster vaccination: The booster dose was administered to the subjects of the phase Ⅲ pivotal clinical trial at the age of 18 months and the immunogenicity data before and after the booster vaccination are shown in Table 4 and Table 5, respectively. (See Tables 4 and 5.)

Click on icon to see table/diagram/image


Click on icon to see table/diagram/image

Cross neutralization study: Pre-vaccination and post-vaccination paired backup serum of 250 subjects from five parallel groups (50 in each group) in the phase Ⅱ clinical trial were used for the cross-neutralization study (10 poliovirus strains), including 4 type 1 strains (Sabin 1 Mahoney, cVDPV1, and imported type 1 wild strain in China in 2011), 3 type 2 strains (Sabin 2, MEF-1, and cVDPV2), and 3 type 3 strains (Sabin 3, Saukett, and cVDPV3).
The immunogenicity results calculated based on PPS are listed as follows: The post-vaccination seropositive rates against all strains of type 1 were 100%; the seroconversion rates were 91%-100%, and the GMTs were 48-1,303. The seropositive rates against all strains of type 2 were 98%-100%; the seroconversion rates were 96%-100% and the GMTs were 209-336. The seropositive rates against all strains of type 3 were 100%; seroconversion rates were 98%-100% and GMTs were 486-647.
Sequential vaccination study: The immunogenicity data of the sequential vaccination study is shown in Table 6, Table 7, Table 8 and Table 9. (See Tables 6, 7, 8 and 9.)

Click on icon to see table/diagram/image


Click on icon to see table/diagram/image


Click on icon to see table/diagram/image


Click on icon to see table/diagram/image