A Study to Qualify an In-house Reference Standard Batch of Sci-B-Vac™

Hepatitis B

SciB018, Prophylactic vaccine, Sci-B-Vac™, HepB vaccines, Phase 4, pre-S1, pre-S2, Surface antigen

Each Sci-B-Vac™ lot to be released to the market is tested in comparison to a reference batch,which has to be tested in a human clinical trial. This study was conducted by SciVac Ltd. to to evaluate the immunogenicity and explore the immune kinetics of Sci-B-Vac™ in support of its qualification as new reference standard which according to the European Pharmacopeia (Ph.Eur. 1056) should elicit ≥ 95% seroprotection rate (SPR) of Hepatitis B surface (HBs) antibody concentrations ≥ 10 milli-International Units (mIU) per ml in young, healthy adult subjects.

This study was a post-marketing, open-label, single arm study in healthy volunteers who had never been vaccinated with any hepatitis B vaccine and were seronegative to HBsAg, Hepatitis B core (HBc) and HBs antibodies. This study consisted of three periods: screening period (up to 1 month prior to first vaccination), treatment (Day 1 to month 6), and post-vaccination follow-up period (months 6 -12). Immunogenicity endpoints were examined one month after the first injection and at every month until month 6, then at months 7, 9 and 12. The primary safety endpoint was the frequency, severity, and duration of adverse events, including clinically-significant laboratory abnormalities after administration of Sci-B-Vac™. Statistical Methods: A total of 92 subjects were recruited into the study. Subjects who fully complied with the study protocol, had no inclusion/exclusion criteria violation and who early terminated the study but reached the primary endpoint prior to withdrawal (modified intention-to-treat (mITT) population) were included in the final population for statistical analysis. mITT population was defined as the subset of the ITT set, which consisted of all enrolled subjects who were vaccinated at least once with Sci-B-Vac™ and had at least one post-vaccination follow-up visit, fully complied with the protocol and had no violation of the inclusion/exclusion criteria. Eligible subjects were followed for a total duration of 12 months. Significance Level: The overall significance level for this study was 5% using two-tailed tests. Sample size determination was performed under the following assumptions: The primary endpoint for the study was the SPR, defined as the proportion of subjects with HBs antibody titer ≥10 mIU/ml by month 7 (i.e. one month after the third immunization with Sci-B-Vac™). Subjects terminated early from the study for any reason at any time and who met the primary endpoint were included. In compliance with the European Pharmacopeia, the SPR threshold was set at ≥ 95%. Based on a 9% margin of non-inferiority, the study was considered successful if the lower bound of the 95.0% exact confidence interval (CI) was 86.0% or more (lower non-inferiority limit) by month 7. The secondary objective of the study was to explore kinetics of immune response induced by Sci-B-Vac™ based on serial immunogenicity measurements. Demographic and baseline data as well as disease prognostic factors, medical history and prior medications were summarized for the mITT population,For continuous variables, descriptive statistics (number \[n\], mean, standard deviation (SD), standard error, median, minimum, and maximum) were provided. For categorical variables, subject counts and percentages were provided.

Participants by arm

Withdrawals & dropouts