Immunogenicity was measured by Hemagglutination Inhibition (HI) assay and summarized through the geometric mean titers (GMTs) at baseline (day 1) and three weeks after the second (day 43) vaccination

Geometric mean ratio (GMR) of subjects was calculated as the ratio of postvaccination to prevaccination HI GMTs three weeks after second (day 43) vaccination.

Percentage of subjects achieving HI seroconversion in HI titer was measured three weeks after second (day 43) vaccination. Seroconversion is defined as postvaccination HI titer\> 40 for subjects with baseline (day 1); HI titer \<1:10 or a minimum 4-fold increase in titer for subjects with baseline titer \>1:10.

Percentage of subjects who achieved HI titers≥1:40 was measured at baseline (day 1) and three weeks after second (Day 43) vaccination.

Safety was assessed as the number of subjects who reported any AEs, and at least possibly related AEs are collected from day 1 to day 43 following vaccination with adjuvanted and unadjuvanted formulations of H7N9c vaccine.

The number of subjects reporting unsolicited adverse events after receiving adjuvanted and unadjuvanted formulations of H7N9c vaccine was reported. Safety was assessed as the number of subjects who reported SAEs, at least possibly related SAEs, new onset of chronic diseases (NOCDs), medically attended AEs, AEs of Special Interest (AESIs), AEs leading to withdrawal from the study were collected from day 1 to day 366 following vaccination with adjuvanted and unadjuvanted formulations of H7N9 vaccine.

Safety was assessed as the number of subjects who reported solicited local and systemic adverse events from day 1 to day 7 of vaccination of adjuvanted and unadjuvanted formulations of H7N9c vaccine.