Comparative efficacy of two dosages of recombinant hepatitis B vaccine in healthy adolescents in India

Prospective clinical trial of hepatitis B vaccination for children with hematological malignancies: a study on the safety and immunogenicity efficacy

Children with hematological malignancies are at increased risk of hepatitis B virus infection. This study assessed the immunogenicity and safety profile of HBV vaccination in pediatric hemato-oncological children. A nonrandomized interventional study was conducted from January 2017 to February 2020 in Shanghai, China. Seventy-three pediatric hemato-oncological children with hepatitis B surface antibody (anti-HBs) titers <10 mIU/ml were recruited. The participants received three doses of recombinant HBV vaccine according to the 0-, 1-, and 6- month immunization schedule. Adverse events following immunization and anti-HBs titers (at baseline, 1 month, and 6 months after inoculation) were recorded. Forty-three males and thirty females with median ages of 9.12 and 9.60 years, respectively, were included. The mean anti-HBs titer was 4.88 ± 2.61 mIU/ml, 893.12 ± 274.12 mIU/ml, and 711.45 ± 337.88 mIU/ml at baseline, one month, and six months after inoculation, respectively (P< .001). A total of fourteen adverse events following immunization were reported, and among them, 5 (6.85%), 5 (6.85%), and 4 (5.48%) events were reported after the first, second, and third inoculation, respectively (P= .927). In conclusions, the HBV vaccine is immunogenic and safe in children with hematological malignancies. It is worth noting that the anti-HBs titer was decreased at the 6-month follow-up, and periodic monitoring of the anti-HBs titer accompanied by timely booster vaccination should be carefully considered.Abbreviations: AEFI: Adverse events following immunization; HBV: Hepatitis B virus; Anti-HBs: Antibody against hepatitis B surface antigen; HBsAg: Hepatitis B surface antigen; APC: Antigen-presenting cell; HSCT: Hemopoietic stem cell transplantation; COVID-19: Corona Virus Disease 2019.

Suitable hepatitis B vaccine for adult immunization in China: a systematic review and meta-analysis

Hepatitis B virus (HBV) infection remains an important public health problem in China, and adults need to be vaccinated. This systematic review and meta-analysis assessed the appropriate immunization of adults in China. Only randomized controlled trials (RCTs) were eligible, and seroprotection was defined as anti-HBs≥ 10 mIU/ml; 18,308 participants in 27 studies were included. Relative risk (RR) and random effects models were used. Twenty micrograms of HBV vaccine resulted in a better response than 10 μg (RR: 1.05, 95% confidence interval (CI): 1.02 to 1.08), and the 0-, 1-, and 6-month schedule was more effective than the 0-, 1-, and 2 - or 3-month schedule (RR: 0.98, 95% CI: 0.96 to 1.00). No significant differences were observed between 10 μg and 5 μg (RR: 1.05, 95% CI: 0.88 to 1.01); (yeast-derived hepatitis B vaccines) YDV and recombinant Chinese hamster ovary cell (CHO) hepatitis B vaccine (RR: 1.01, 95% CI: 0.98 to 1.04); domestic and imported (RR: 1.02, 95% CI: 0.99 to 1.05); or 0-, 1-, and 6-month and 0-, 1-, and 12-month schedules (RR: 1.02, 95% CI: 0.89 to 1.08). In conclusion, 20 μg of vaccine is recommended for adults in China, and the 0-, 1-, and 12-month immunization program schedule is also worth choosing when it is not possible to complete the 0-, 1-, and 6-month schedule.

High coverage of hepatitis B vaccination and low prevalence of chronic hepatitis B in migrant children dictate a new catch-up vaccination strategy

BACKGROUND

Worldwide coverage of hepatitis B (HB) vaccination is increasing. This should be considered when determining the best strategy for catch-up HB vaccination in migrant children, who rarely have written proof of past immunizations. This study aimed to estimate HB vaccine protection, chronic HB prevalence and to identify determinants of vaccine protection.

METHODS

Newly arrived migrant children at Lausanne University Hospital from October 2014 to July 2017 were prospectively enrolled. Children and adolescents aged 1-18 years were approached for inclusion if they had no proof of past vaccinations and accepted a single dose of injected HB vaccine. HB surface antibody (anti-HBs) serology was performed after 4-6 weeks. Anti-HBs ≥100 IU/L were considered consistent with a booster-type antibody response. Patients with anti-HBs <100 IU/L received additional dose(s) of HB vaccine, after exclusion of chronic HB in children with anti-HBs <10 IU/L. Potential determinants of vaccine response were compared between children with and without booster-type response.

RESULTS

Two hundred children were available for analysis. Median age was 8.9 years (IQR 4.8-12.9), and 97 (49%) were female. The majority (n = 124, 62%) came from the region classified by the WHO as eastern Mediterranean. One hundred and sixty-one children (81%) had a booster-type antibody response. Only 1 patient (<1%) had chronic HB. In the multivariate analysis, younger age (OR per decreasing-year, 1.28; 95%CI, 1.05-1.57; p = 0.017) and migration from an urban area (OR 1.16; 95%CI, 1.01-1.33; p = 0.043) were the only significant determinants of booster-type response.

CONCLUSION

Post-vaccine serology may be used to identify a high proportion of individuals in our pediatric migrant population with previous immunization for HB. Our study also showed extremely low prevalence of chronic HB. No variable could definitively determine the results of serology. Post-vaccine serology represents the most effective strategy in this context of high vaccine coverage.

Comparison of immunogenicity between hepatitis B vaccines with different dosages and schedules among healthy young adults in China: A 2-year follow-up study

Immunogenicity of hepatitis B vaccine between 20 μg with 3-dose schedule and 60 μg with 2-dose regimens was compared 2 years after primary immunization. A total of 353 healthy adults aged 18-25 years were enrolled in the study and randomly assigned (1: 1: 1) into 3 vaccine groups: A (20 μg, 0-1-6 month), B (60 μg, 0-1 month) and C (60 μg, 0-2 month). Serum samples were collected at 1 month after a series vaccination and 12 months, 24 months after the first-dose. The GMC level of anti-HBs antibody was measured using Chemiluminescent Microparticle ImmunoAssay (CMIA). There were 59, 45 and 55 vaccinees available to follow-up with 2 year later in vaccine groups A, B and C, respectively. No significant differences existed in sex ratio, age and body mass index (BMI) among vaccinees at month 24 and the corresponding participants at baseline in each group (P > 0.05). The seroprotection rates in group A, B and C were 98.31%, 88.37% and 85.19%, respectively (P = 0.014), reflecting the fact that the rate of group A was significantly higher than that in group C (P = 0.026). Also, the GMC level of anti-HBs antibody in group A was significantly higher than those of other two groups (427.46 mIU/ml vs. 89.74 mIU/ml, 89.80 mIU/ml, respectively; all P < 0.01). This data suggested that the standard 20 μg (0-1-6 month) regimen of hepatitis B vaccine should be recommended as a priority on the premise of complete compliance in adults.

Rapid immunization effects of a new type of 60 μg hepatitis B vaccine compared with traditional 20 μg hepatitis B vaccines in adults

BACKGROUND

The widely recommended standard schedule of hepatitis B vaccine for adults is months 0, 1 and 6, which takes 6 months to complete. Rapid completion of one vaccination schedule is important to adults because of its low compliance with follow-up doses. A new type of 60 μg Hepatitis B vaccine, made by Shenzhen Kangtai Biological Products Co., LTD., is originally recommended for low or non-responders. The objective of this clinical trial was to test whether this 60 μg hepatitis B vaccine could be used in primary immune population and what is its level of immunogenicity and safety compared with other hepatitis B vaccines.

METHODS

This is a 2-center randomized controlled study. A total of 1169 healthy adults aged between 25 and 55 who tested negative for HBsAg, anti-HBs, and anti-HBc were eligible for the study and were enrolled from relatively fixed and stable sites, such as villages, schools and large enterprises et al in Xuanhua county in Hebei province and Huaibei county in Anhui province. They were randomized to group A (20 μg Engerix-B® with 0, 1, 6 month intervals), group B (20 μg Kangtai hepatitis B vaccine with 0, 1, 6 month intervals), group C (60 μg Kangtai hepatitis B vaccine with 0, 2 month intervals) and group D (20 μg Huabei hepatitis B vaccine made by recombinant DNA techniques in CHO cell with 0, 1, 6 month intervals). In group A, B and D, every study object's blood sample was collected in the second month after their final injection to test the anti-HBs levels; while in group C, the blood sample was collected in the second month after the first and the second injection to test the anti-HBs levels. Adverse events were collected after each dose to assess the vaccines' safety.

RESULTS

The seroprotection rates were 93.17%, 97.23%, 93.54% and 98.98% respectively and the geometric mean titers (GMTs) were 1033.38 mIU/ml, 600.75 mIU/ml, 265.69 mIU/ml and 1627.05 mIU/ml in group A,B,C and D respectively. The difference of seroprotection rate among the 4 groups was statistically significant (χ² = 17.26, P<0.05). The difference of titers of anti-HBs among the 4 groups was statistically significant (H = 162.42, P<0.05). BMI, age (older than 40) and smoking were the influence factors of anti-HBs levels on 60 μg hepatitis B vaccine.

CONCLUSION

60 μg hepatitis B vaccine has a satisfactory safety and seroprotection rate in adult, It could be used in rapid adult hepatitis B immunization.

Comparison of the effect of increased hepatitis B vaccine dosage on immunogenicity in healthy children and adults

Hepatitis B (HepB) infection remains a global public health problem, particularly in China. Vaccination for children and adult who are unvaccinated is an effective method for preventing the disease. In this study, we aimed to compare the effects of increased dosage of HepB vaccine on immunogenicity in healthy children and adults. A phase III, controlled, double-blinded clinical trial was performed. The subjects were assigned into groups I (age 5-14 y), II (age 15-24 y), and III (age ≥ 25 y). Subjects were randomly administered either 10 or 5 μg recombinant HepB vaccine; blood samples were collected before and after vaccination to estimate immunogenicity. The results showed that the seroconversion rate and geometric mean concentration of antibody to hepB surface antigen (anti-HBs) did not differ significantly between the dosages in each age group. Anti-HBs levels were reduced with age, and this effect was more obvious in adults administered 5 μg HepB vaccine. In conclusion, both vaccine dosages could be used to immunize children, and the 10 μg vaccine could be used for adults ages 15-24 y, whereas a higher dosage of the HepB vaccine may be required for adults ages 25 y and older.

Mechanisms of aluminum adjuvant toxicity and autoimmunity in pediatric populations

Immune challenges during early development, including those vaccine-induced, can lead to permanent detrimental alterations of the brain and immune function. Experimental evidence also shows that simultaneous administration of as little as two to three immune adjuvants can overcome genetic resistance to autoimmunity. In some developed countries, by the time children are 4 to 6 years old, they will have received a total of 126 antigenic compounds along with high amounts of aluminum (Al) adjuvants through routine vaccinations. According to the US Food and Drug Administration, safety assessments for vaccines have often not included appropriate toxicity studies because vaccines have not been viewed as inherently toxic. Taken together, these observations raise plausible concerns about the overall safety of current childhood vaccination programs. When assessing adjuvant toxicity in children, several key points ought to be considered: (i) infants and children should not be viewed as “small adults” with regard to toxicological risk as their unique physiology makes them much more vulnerable to toxic insults; (ii) in adult humans Al vaccine adjuvants have been linked to a variety of serious autoimmune and inflammatory conditions (i.e., “ASIA”), yet children are regularly exposed to much higher amounts of Al from vaccines than adults; (iii) it is often assumed that peripheral immune responses do not affect brain function. However, it is now clearly established that there is a bidirectional neuro-immune cross-talk that plays crucial roles in immunoregulation as well as brain function. In turn, perturbations of the neuro-immune axis have been demonstrated in many autoimmune diseases encompassed in “ASIA” and are thought to be driven by a hyperactive immune response; and (iv) the same components of the neuro-immune axis that play key roles in brain development and immune function are heavily targeted by Al adjuvants. In summary, research evidence shows that increasing concerns about current vaccination practices may indeed be warranted. Because children may be most at risk of vaccine-induced complications, a rigorous evaluation of the vaccine-related adverse health impacts in the pediatric population is urgently needed.

Hepatitis B vaccination strategies tailored to different endemicity levels: some considerations

Hepatitis B is a serious public health problem. Worldwide three different levels of hepatitis B endemicity (high, intermediate and low) can be distinguished. Areas with different levels of endemicity require tailored vaccination strategies to fit the needs for individuals at risk and/or countries, depending on the infection risk per age group, vaccination rate, duration of protection after vaccination, cost effectiveness of vaccination strategies and ease of implementation in the national immunization schedules.This opinion paper evaluates these factors and proposes a combination of infant risk group and universal adolescent vaccination for low endemic countries thus targeting the different groups at risk. A universal infant vaccination schedule starting with a newborn vaccination within 24h after birth is more appropriate in intermediate- and high-endemic regions.

Development of up-converting phosphor technology-based lateral-flow assay for rapidly quantitative detection of hepatitis B surface antibody

An up-converting phosphor technology-based lateral-flow (UPT-LF) assay system was developed for rapid and quantitative detection of hepatitis B surface antibody (HBsAb). To evaluate its performance, we compared it with the Abbott Axsym AUSAB (ABBOTT Diagnostics Division, Wiesbaden, Germany) assay and conventional ELISA (Wantai Biological Pharmacy Enterprise, Beijing, China) using 13 standard positive sera and 306 clinical sera. In both laboratory evaluation and clinical application, UPT-LF assay showed the best sensitivity (99.19%) and detection agreement (97.43% for the adjusted agreement) with true results. The concordance rate between UPT-LF and ELISA, as shown by correlative regression analysis, was the highest (R(2)=0.6389), whereas that between UPT-LF and AUSAB was the lowest (R(2)=0.5702). In conclusion, UPT-LF assay for quantitative detection of HBsAb is sensitive and rapid, promising this new assay a bright future.