Antibody persistence and immune memory in adults, 15 years after a three‐dose schedule of a combined hepatitis A and B vaccine

Abstract

A combined hepatitis A and B vaccine is available since 1996. Two separate open-label primary studies evaluated the immunogenicity and safety of this hepatitis A and B vaccine (720 EI.U of HAV and 20 µg of HBsAg) in 306 healthy subjects aged 17-43 years who received three doses of the vaccine following a 0, 1, and 6 months schedule. These subjects were followed up annually for the next 15 years to evaluate long-term persistence of anti-HAV and anti-HBs antibodies. The subjects whose antibody concentrations fell below the cut-offs between Year 11 and Year 15 (anti-HAV: <15 mIU/ml; anti-HBs: <10 mIU/ml) were offered an additional dose of the appropriate monovalent hepatitis A and/or B vaccine. In subjects who received the additional vaccine dose, a blood sample was collected 1 month after vaccination. At the Year 15 time point, all subjects in Study A and Study B were seropositive for anti-HAV antibodies and 89.3% and 92.9% of subjects in the respective studies had anti-HBs antibody concentrations ≥10 mIU/ml. Four subjects (two in each study) received an additional dose of monovalent hepatitis B vaccine and mounted anamnestic responses to vaccination. No vaccine-related serious adverse events were reported. This study confirms the long-term immunogenicity of the three-dose regimen of the combined hepatitis A and B vaccine, as eliciting long-term persistence of antibodies and immune memory against hepatitis A and B for up to at least 15 years after a primary vaccination.

Persistence of immunity in healthy adults aged ≥50 years primed with a hepatitis B vaccine 3 years previously

“…[15][16][17][18][19][20][22][23][24][25][26] The post-challenge SPRs and GMTs observed in this extension study were also comparable to or higher than those reported at the end of the primary vaccination series (Dose 3) for both groups (HBvaxPRO Ò group: 79.5% and 152.9 mIU/mL, respectively, at the end of the primary study, and 85.2% and 957.4 mIU/mL, respectively, post-challenge; Engerix B TM group : 88.3% and 437.2 mIU/mL, respectively, at the end of the primary series, and 88.3% and 1,497.6 mIU/mL, respectively, postchallenge).…”

“…[27][28][29] Booster vaccinations are reported to be very effective in older individuals in case of inadequate response to primary vaccination. 12 Routine booster vaccination is not usually recommended for children or adults 3,19,20,[24][25][26] as it is difficult to identify individuals who would benefit from the procedure.…”

Immunogenicity, effectiveness and safety of combined hepatitis A and B vaccine: a systematic literature review

“…After full vaccination, the rate of seropositivity for anti-HAV ranged from 96.2% to 100%, regardless of the schedule used or whether the study was done in adults or children (Tables 2-4) [11,12,14,[18][19][20][22][23][24][25][27][28][29][30]32,[34][35][36][37]. Two articles reported lower seropositivity rates at month 7.…”

“…After the third dose, the GMC ranged from 2747 to 8895 mIU/ml [11,12,14,19,20,[22][23][24][25][27][28][29][30]34,35], which is well above the seropositivity cut-off levels, inferring seroprotection. However, GMC decreased with increasing age and body mass index (BMI) [23,27,33] was lower in HCV-positive adults [12], and it was lower in smokers compared to nonsmokers [24,27].…”

“…Three presentations of the combined vaccine against hepatitis A and B (Twinrix TM , Twinrix Pediatric TM , and Ambirix TM ; GSK Vaccines, Belgium) are available [3,14], see Table 1. These vaccines are able to confer concurrent protection against the two infections while reducing the number of injections, associated costs, and other logistical issues.…”