The primary purpose of this Phase 3 study is to determine whether the preventive hepatitis E is effective in the prevention of hepatitis E occurring at least 30 days after the administration of the third dose of vaccine.

The secondary purpose of this study is to evaluate the safety and immunogenicity and immunopersistence of the study vaccine.

Results

On September 11, 2010, the Lancet published the results of this clinical trial.

11,165 of the trial participants were tested for hepatitis E virus IgG, of which 5285 (47%) were seropositive for hepatitis E virus. Participants were randomly assigned to vaccine (n=5602) or placebo (n=5602). 4,693 (86%) participants in the vaccine group and 4,663 participants (86%) in the placebo group received three vaccine doses and were included in the primary efficacy analysis. During the 12 months after 30 days from receipt of the third dose 15 per-protocol participants in the placebo group developed hepatitis E compared with none in the vaccine group. Vaccine efficacy after three doses was 100.0% (95% CI 72.1-100.0). Adverse effects attributable to the vaccine were few and mild. No vaccination-related serious adverse event was noted.

Conclusion

HEV 239 is well tolerated and effective in the prevention of hepatitis E in the general population in China, including both men and women age 16-65 years.