Enhanced immune response to hepatitis B vaccination through immunization with a Pre-S1/Pre-S2/S Vaccine

Abstract

Efficacy and safety of recombinant yeast-derived hepatitis B vaccines for prevention of hepatitis B have been demonstrated unequivocally worldwide as reflected in reduction in HBsAg carrier rates and hepatocellular carcinoma. A new generation of recombinant HBV vaccines expressed in mammalian cells containing Pre-S/S epitopes has been developed in several countries. Such vaccines are useful in special risk groups, i.e., in non-responders to conventional HBV vaccines including older adults, obese people, health care workers, patients with renal failure and on dialysis, transplant patients, patients with HIV as well as travelers on short notice to HBV endemic regions. The future of such vaccines depends on their enhanced immunogenicity and cost profile. Sci-B-Vac™ is a mammalian cell-derived recombinant Pre-S1/Pre-S2/S hepatitis B vaccine which has been shown to be highly immunogenic, inducing faster and higher seroprotection rates against HBV with higher anti-HBs levels at lower HBsAg doses as compared to conventional yeast-derived vaccines. Recently, it has been suggested that such Pre-S/S vaccines against HBV might be efficacious not only for prevention but also for intervention in persistent HBV infection. Data obtained in a recent clinical trial conducted in Vietnam in patients with chronic hepatitis B suggest that repeated monthly i.m. injections of the Sci-B-Vac™ co-administered with daily oral lamivudine treatment can suppress HBV replication and lead to anti-HBs seroconversion in ~50 % of treated patients. Optimization of protocols and efficacy of such an intervention, intended to bypass T cell exhaustion and immune tolerance to HBV remains to be explored.

Control of hepatitis B virus infection in hematopoietic stem cell recipients after receiving grafts from vaccinated donors

“…As compared with conventional (second generation) HBV vaccines, HBV immunity develops earlier and immunity is stronger after application of the third generation vaccines. 11,13,14 In the current study, anti-HBs clearly increased in patient 1 after receiving a graft from the donor vaccinated with a third generation vaccine. On the contrary, even a decline in anti-HBs titers was observed in patient 2 receiving a graft from the donor vaccinated with a conventional HBV vaccine.…”

Virosomes of hepatitis B virus envelope L proteins containing doxorubicin: synergistic enhancement of human liver-specific antitumor growth activity by radiotherapy

“…However, BNC (targeting molecule of virosomes) has already been shown as a safe biomaterial in humans. 30,31 And, the LP-DOX complexes (ie, Doxil, DOXOVES) have also been confirmed safe in human. 26 It was therefore considered that the virosomes containing DOX are not cytotoxic in vivo.…”

Recombinant Hepatitis B Vaccine Adjuvanted With AS04 in Dialysis Patients: A Prospective Cohort Study

“…Since the mid 1980s, second-generation recombinant hepatitis B vaccines have gradually replaced the plasma-derived vaccines even among patients with CKD. Second-generation vaccines have been made in yeasts transfected with HBV-DNA sequences coding for the small hepatitis B surface protein (SHBs) [15]. They are currently used for universal vaccination of newborns and adults in >170 countries worldwide.…”