Interchangeability and tolerability of two inactivated hepatitis A vaccines in Chinese children

Safety and 6-month immune persistence of inactivated poliovirus vaccine (Sabin strains) simultaneously administrated with other vaccines for primary and booster immunization in Jiangxi Province, China

OBJECTIVES

This study aims to evaluate the safety of a new inactivated poliomyelitis vaccine (Sabin strains) (sIPV) for large-scale use in primary and booster immunizations, whether simultaneously administered with other vaccines or not and to explore the persistence of all vaccines at approximately six months after vaccination.

METHOD

A total of 3200 infants were recruited into this study, including 2000 infants aged 2-3 months randomly assigned (1:1) into the "sIPV basic" or the "sIPV+DTaP" group for primary immunization of sIPV. Another 1200 children aged 18 months old and above were randomly assigned (2:2:1:1) into the "sIPV booster," "sIPV+HepA-I," "sIPV+MMR", or "sIPV+HepA-L" group for booster immunization of sIPV. Adverse events within 30 days of each vaccination dose in all participants were self-reported by guardians using a WeChat mini-program. Approximately 200 blood samples were collected at 5-7 months after the final vaccination to test for antibodies against poliovirus and other viruses.

RESULTS

3198 participants in total were included in the safety study, including 1999 infants aged 2-3 months old and 1199 children aged 18-26 months old. For primary immunization, the incidence of adverse reactions in the "sIPV basic" and the "sIPV+DTaP" group were 3.19 and 6.21% (P = 0.001), respectively. For booster immunization, the incidences of adverse reaction for the "sIPV booster" group were 2.25%, while the incidence for the "sIPV +others" group in total was 2.50% (P = 0.788). Most adverse reactions were mild. Fever was the most common symptom in all groups. No vaccine-related serious adverse events (SAEs) were observed in this study. The seropositivity rates of antibodies in the "sIPV basic" and the "sIPV+DTaP" group were 92.31 and 100% against type 1 poliovirus (P = 0.031); 96.15% and 98.57% against type 2 poliovirus (P = 0.575); 98.08% and 91.43% against type 3 poliovirus (P = 0.237), respectively. Regarding booster vaccination with sIPV, whether co-administered with other vaccines or not, the seropositivity rates of antibodies against the three types of polioviruses were all 100%. Seropositivity rates of antibodies against hepatitis A, measles, mumps, and rubella were all no <77%, except for pertussis, which was <30%.

CONCLUSION

sIPV demonstrated good safety and immune persistence for primary and booster vaccinations, whether administered singly or simultaneously. Antibodies against hepatitis A, measles, mumps and rubella were not disrupted by the co-vaccination. However, the seropositivity rates and geometric mean concentrations (GMCs) of antibodies against pertussis indicate the necessity for a booster dose.

Immunogenicity and safety of a live attenuated varicella vaccine co-administered with inactive hepatitis A vaccine: A phase 4, single-center, randomized, controlled trial

Co-administration of vaccines can facilitate the introduction of new vaccines in immunization schedules. This study aimed to evaluate the immunogenicity and safety of co-administration with live attenuated varicella vaccine (VarV) and inactivated hepatitis A vaccine (HepA) among children aged 12 ~ 15 months. In this phase 4 clinical trial, 450 children were randomized with a ratio of 1:1 to receive VarV and Hep A simultaneously (Group A) or separately (Group B). The primary endpoints were the seroconversion rate of anti-varicella-zoster virus (VZV) antibodies 42 days after vaccination of VarV and the seroconversion rate of anti-Hepatitis A virus (HAV) antibodies 30 days after two-dose vaccination of HepA. After full immunization, the seroconversion rates of anti-VZV antibodies were 91.79% in Group A and 92.15% in Group B; the geometric mean titers (GMTs) were 11.80 and 12.19, respectively. The seroconversion rates of anti-HAV antibodies were 99.48% in Group A and 100.0% in Group B; the geometric mean concentrations (GMCs) reached 9499.11 and 9528.36 mIU/ml, respectively. The lower limits of the 95% CI for the seroconversion difference of anti-VZV antibodies and anti-HAV antibodies were -5.86% and -2.90%, which greater than the predefined non-inferiority margin (-10%). The incidence rate of adverse reactions in Group A was lower than Group B (9.33% vs 16.22%), and only one serious adverse event was reported in Group B, which was unrelated to the study vaccine. In conclusion, the co-administration of VarV with HepA has non-inferior immunogenicity and safety profiles were quite comparable with the separate administration of both vaccines.Trial registration number: NCT05526820 (ClinicalTrials.gov).

Hepatitis A vaccination

Hepatitis A is an important public health issue worldwide. Hepatitis A vaccine (HepA) was first licensed in 1992. Both inactivated HepA (HepA-I) and live attenuated HepA (HepA-L) are highly immunogenic and well tolerated, and immune protection postvaccination can persist for at least 20 y. HepA is effective for both preexposure and postexposure prophylaxis, especially among children and young adults. The strategy of HepA vaccination varies in different countries and mainly includes vaccination among high-risk populations, regional childhood vaccination and universal childhood vaccination. The incidence of hepatitis A has decreased greatly in many countries in the last 30 y, but hepatitis A outbreaks frequently occur among high-risk populations and those who have not been covered by universal child vaccination programs in recent years. Disease surveillance and serosurveys are suggested to clarify the shift in the epidemiology of hepatitis A. The long-term persistence of immune protection after one dose of HepA should be further studied, as well as the cost-effective evaluation of different strategies of HepA vaccination. Based on this evidence, the recommendation on HepA vaccination should be put forward scientifically and updated in a timely and well-implemented manner.

Interchangeability of two Enterovirus 71 inactivated vaccines in Chinese children: A phase IV, open-label, and randomized controlled trial

BACKGROUND

In China, three inactivated Enterovirus 71 (EV71) vaccines have been approved. Although the vaccines in an immunization series should be from a single manufacture, children sometimes have to receive EV71 vaccines from more than one manufacturers. The aim of this study was to evaluate the interchangeability and safety of vaccination with EV71 vaccines from two manufacturers among Chinese children.

METHODS

We conducted an open label and randomized controlled study among children aged 6-35 months from November 2018 to January 2019. The participants were randomly assigned (1:1:1:1) to receive EV71 vaccines in one of the four different schedules (two using a single vaccine for all doses from one manufacture, and two mixed schedules using vaccines from two manufactures). Blood samples were collected pre-vaccination (Day 0) and one month after the second dose (Day 60) for neutralizing antibody assay. Immunogenicity was assessed in the per-protocol cohort and safety was assessed in the total vaccinated cohort.

RESULTS

A total of 300 children were enrolled and randomized, of whom 89.0% (267/300) were included in the per-protocol cohort for immunogenicity analysis. The seroconversion rates of the EV71 neutralizing antibody in four groups ranged from 98.4% to 100.0%, and were not significantly different among the groups. Compared with other groups, geometric mean titer was higher in group D, in which the participants received Institute of Medical Biology Chinese Academy of Medical Sciences (CAMS) vaccine in the first dose and the Sinovac vaccine in the second dose. Safety profiles were similar among the four groups and no serious adverse events related to the vaccination were reported.

CONCLUSIONS

Interchangeability of EV71 vaccines from two manufactures to complete an immunization series showed good immunogenicity and safety. The antibody response levels may vary by vaccination sequences of EV71 vaccines from the two manufacturers.

TRIAL REGISTRATION

ClinicalTrials.govNCT03873740.

Five-year antibody persistence in children after one dose of inactivated or live attenuated hepatitis A vaccine

In China, both inactivated hepatitis A (HA) vaccine and live attenuated HA vaccine are available. We conducted a trial to evaluate 5-year immune persistence induced by one dose of inactivated or live attenuated HA vaccines in children. Subjects with no HA vaccination history had randomly received one dose of inactivated or live attenuated HA vaccine at 18-60 months of age. Anti-HAV antibody concentrations were measured before vaccination and at the first, second, and fifth year after vaccination. Suspected cases of hepatitis A were monitored during the study period. A total of 332 subjects were enrolled and 182 provided evaluable serum samples at all planned time points. seropositive rate at 5 y was 85.9% in the inactivated HA vaccine group and 90.7% in the live attenuated HA vaccine group. GMCs were 76.3% mIU/ml (95% CI: 61.7 - 94.4) and 66.8mIU/ml (95% CI: 57.8 - 77.3), respectively. No significant difference in antibody persistence between 2 groups was found. No clinical hepatitis A case was reported. A single dose of an inactivated or live attenuated HA vaccine at 18-60 months of age resulted in high HAV seropositive rate and anti-HAV antibody concentrations that lasted for at least 5 y.

Comparison of immune persistence among inactivated and live attenuated hepatitis a vaccines 2 years after a single dose

OBJECTIVE

Compare immune persistence from one dose of each of 3 different hepatitis A vaccines when given to school-age children: a domestic, live attenuated hepatitis A vaccine (H2 vaccine); a domestic inactivated hepatitis A vaccine (Healive®); and an imported, inactivated hepatitis A vaccine (Havrix®),.

METHODS

School-age children were randomized into 1 of 4 groups to receive a single dose of a vaccine: H2 vaccine, Healive®, Havrix®, or hepatitis B vaccine [control]. Serum samples were collected 12 and 24 months after vaccination for measurement of anti-HAV IgG using microparticle enzyme immunoassay. Seropositivity was defined as ≥ 20 mUI/ml. We compared groups on seropositivity and geometric mean concentration (GMC).

RESULTS

Seropositive rates for the H2, Healive®, Havrix®, and control groups were 64%, 94.4%, 73%, and 1.0%, respectively, 12-months post-vaccination; and 63%, 95.6%, 72%, and 1.0%, respectively 24-months post-vaccination. Seropositivity was greater for Healive® than for H2 and Havrix® at 12 months (p-values < 0.001) and 24 months (p-values < 0.0001). Average GMCs for the H2, Healive®, Havrix®, and control groups, in mIU/ml, were 29.7, 81.0, 36.4, and 2.9, respectively at 12 months, and 30.9, 112.2, 44.3, and 2.9, respectively, at 24 months. GMCs were greater for Healive® than for H2 and Havrix® at 12 months (p-values < 0.0001 and < 0.001, respectively) and 24 months (p-values < 0.001). No statistically significant differences in seropositivity or GMC were found within groups between 12 and 24 months.

CONCLUSION

Immunity persisted 24 months after a single dose of inactivated hepatitis A vaccine and live attenuated hepatitis A vaccine.

Advances in hepatitis immunization (A, B, E): public health policy and novel vaccine delivery

PURPOSE OF REVIEW

This review offers an update on hepatitis A, B and E vaccines based on relevant literature published in 2011-2012. Hepatitis A and B vaccines have been commercially available for years; however, the development of the hepatitis E vaccine is still facing some challenges.

RECENT FINDINGS

Current scientific evidence shows that both hepatitis A and B vaccines confer long-term protection. These data supported the updated recommendations from the WHO on hepatitis A and B vaccines and the respective booster policy. In addition, a single-dose hepatitis A vaccination programme may be an option for some intermediate endemic countries, as far as the epidemiological situation is further monitored. Recent data illustrate the co-administration of hepatitis A with infant vaccines, as well as the interchangeability with other hepatitis A vaccines. Two genetically engineered hepatitis E vaccines are currently in development, showing more than 95% protective efficacy.

SUMMARY

Follow-up of vaccinated individuals confirms the long-term protection offered by the hepatitis A as well as hepatitis B vaccines. Data confirm the safety and immunogenicity profile of both vaccines, also when used in patient groups. The first data on the hepatitis E vaccine look promising, but questions on cross-protection, long-term efficacy and safety and immunogenicity in pregnant women and children less than 2 years remain unanswered.

Review of 10 years of marketing experience with Chinese domestic inactivated hepatitis A vaccine Healive®

In 2002, the first Chinese domestic preservative-free inactivated hepatitis A vaccine, Healive®, was introduced in China. It is highly immunogenic, and provides lasting protection in healthy individuals and generates protective levels of antibodies in other at-risk individuals. Over 10 years since its first licensure, postmarketing surveillance data have confirmed the outstanding safety profile of the vaccine. Comparative clinical trials indicated that Healive® induce equal or similar immunogenicity with other currently available inactivated hepatitis A vaccines and are interchangeable for the course of HAV immunization in Chinese children. The vaccine is effective in curbing outbreaks of hepatitis A due to rapid seroconversion and the long incubation period of the disease. Additional issues surrounding the use of the vaccine are also reviewed.