Adult Hepatitis B Vaccination Using A Novel Triple Antigen Recombinant Vaccine

Abstract

Present hepatitis B vaccines use multidose prolonged regimens, which even healthcare workers at risk do not always complete. Moreover, when vaccination is completed there remain some who fail to achieve adequate protection. The protection of adults at risk could be improved if there were a more potent vaccine and/or a shorter vaccination regimen available. Vaccine-naive adults were randomized to vaccination with either Engerix-B (SmithKline Biologicals, Rixensart, Belgium) or a novel triple antigen (S, pre-S1, and pre-S2) recombinant vaccine (Hepacare; Medeva Pharma Plc, Speke, UK). The primary efficacy parameter was the degree of seroprotection 6 or 7 months (26 ؎ 2 weeks) after beginning vaccination. A total of 304 adults entered the study. Of these, 16 failed to complete the study (9 on Hepacare and 7 on Engerix-B). With the Engerix-B standard (0, 1, 6) regimen, 88% of subjects were protected by month 7, whereas with the triple antigen vaccine a 2-dose regimen (0, 1) provided equivalent protection (91%) within 6 months and a 3-dose (0, 1, 6) regimen was significantly superior (98% seroprotected by 7 months after starting vaccination P < .001). With adults at risk for a suboptimal response (i.e., older adults, the obese, men, and smokers) the triple antigen vaccine produced a greater degree of protection. The vaccines had similar safety profiles. Both vaccines were well tolerated. In healthy normal adults, a triple antigen hepatitis B vaccine containing S and pre-S antigens produced an enhanced immunologic response and was as effective as a 2-and 3-dose regimen. (HEPATOLOGY 2001;34:372-376.)Although hepatitis B is largely a disease of the developing world, it is still a problem in the developed world. The estimated annual incidence of new infections of hepatitis B in the United States has varied from 200,000 to 300,000 new cases each year over the past decade. 1-3 Much of the disease is subclinical and a recent estimate 4 has suggested some 6-fold under-reporting with a true incidence of 1,000,000 new cases every year in Europe alone. All this is despite the availability of vaccines for over 2 decades.Although much of the problem has been the limited population in whom the vaccine was used initially there are other issues. First, all hepatitis B vaccines to date show a decreased response in certain subjects such as older adults, men, smokers, and the obese as well as when given intradermally or in the buttocks rather than in the deltoid muscle. [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] Second, present vaccines are usually given in a 6-month/3-dose (0, 1, and 6 months) regimen. 20,21 This implies that protection is not provided to a significant number of adults until some 7 months after beginning a course of vaccination. The implication is reinforced by the development of a so-called "accelerated course" of 3 doses given within 2 months (0, 1, and 2 months) for those who require rapid protection. 20,22 Unfortunately, this course does not deliver longer-term protection, and a booster dose at 12 mon...

Serologic and Molecular Characteristics of Hepatitis B Virus among School Children in East Java, Indonesia

“…In Indonesia, recombinant hepatitis B -L62 +/+ S113T T126I, T143S --L119 -/+ K24R,Q56P,I57T,C64S, S113T T126I, T143S --vaccines that include pre-S1 and pre-S2 regions currently unavailable. However, this new triple-antigen vaccine is more efficient than the single-antigen vaccine, 20,21 and prevents infection from vaccine-escape mutants. 22 The triple-antigen vaccine should be considered in our study area where the prevalence of anti-HBs remains insufficient among children.…”

Construction of a fusion gene containing hepatitis B virus L gene and Mycobacterium tuberculosis Ag85B gene and its expression in Pichia pastoris

“…The S gene region includes three ATG initiation codons: PreS1, PreS2 and S segments, encoding three kinds of surface antigen protein. S protein is translated by the S region, M protein by the PreS2 and S region and the L protein by the PreS1, PreS2 and S regions (Young et al, 2001). Thus, when the L and S protein were compared, the L protein has PreS1 and PreS2.…”

Vaccination against viral hepatitis b in pediatric liver transplant recipients

“…В дополнение к S-антигену один из них со-держит антиген из пре-S2-области, в то время как другие два содержат антигены как из пре-S1, так и из пре-S2-области. Этот класс вакцины продемонс-трировал большую иммуногенность по сравнению с вакциной второго поколения [43]. Хотя вакцины с пре-S-антигенами могут быть более эффективны-ми, они не являются широко доступными в настоя-щее время.…”