Abstract
An additional one to three doses of hepatitis B vaccine are recommended for nonresponders to an initial standard three-dose series. We compared the safety and immunogenicity of an investigational hepatitis B surface antigen vaccine (HBsAg-1018) with a phosphorothioate oligodeoxyribonucleotide adjuvant that targets toll-like receptor-9 to a commercially available, alum-adjuvanted hepatitis B vaccine (HBsAg-Eng) in nonresponders to three previous doses (primary study) or to four to six previous doses (substudy) of HBsAg-Eng. Both vaccines were well tolerated, although HBsAg-1018 was associated with more injection-site tenderness (63.2% vs. 18.8%, p = 0.016 in the primary study and 81.8% vs. 15.4%, p = 0.003 in the substudy). No statistically significant differences in rates of seroprotection (anti-HBs concentration ≥ 10 mIU/mL) or geometric mean antibody concentrations were found in the primary study. In the substudy, a greater proportion of HBsAg-1018 recipients achieved an anti-HBs concentration ≥ 100 mIU/mL (54.5% vs. 8.3%, p = 0.027), and those responders had higher geometric mean antibody concentrations at 4 weeks (264 vs. 46.5 mIU/mL, p = 0.021) and 52 weeks (7.0 vs. 1.2 mIU/mL, p = 0.030) than HBsAg-Eng recipients. Although this study suggests that HBsAg-1018 may have improved immunogenicity in nonresponders to hepatitis B vaccine vaccination when compared with HBsAg-Eng, larger studies are required.
Disclosure of Potential Conflicts of Interest
J.T.M. and W.L.H. are employees of Dynavax Technologies Corporation. All other authors have no financial interest in the vaccine or its manufacturer but received research funding to undertake the study.
The study was funded by Dynavax Technologies Corporation.
Acknowledgments
We thank the participants of the study and the research staff at the three enrollment sites for their careful attention to detail. This study was funded by Dynavax Technologies Corporation.