Improving hepatitis B vaccine efficacy in end-stage renal diseases patients and role of adjuvants

Global Perspectives on the Hepatitis B Vaccination: Challenges, Achievements, and the Road to Elimination by 2030

Annually, more than 1.5 million preventable new hepatitis B (HBV) infections continue to occur, with an estimated global burden of 296 million individuals living with chronic hepatitis B infection. This substantial health challenge results in over 820,000 annual deaths being attributed to complications such as liver cirrhosis and hepatocellular carcinoma (HCC). The HBV vaccination remains the cornerstone of public health policy to prevent chronic hepatitis B and its related complications. It serves as a crucial element in the global effort to eliminate HBV, as established by the World Health Organization (WHO), with an ambitious 90% vaccination target by 2030. However, reports on global birth dose coverage reveal substantial variability, with an overall coverage rate of only 46%. This comprehensive review thoroughly examines global trends in HBV vaccination coverage, investigating the profound impact of vaccination on HBV prevalence and its consequences across diverse populations, including both high-risk and general demographics. Additionally, the review addresses the essential formidable challenges and facilitating factors for achieving WHO's HBV vaccination coverage objectives and elimination strategies in the coming decade and beyond.

Seroconversion following Heplisav-B, hepatitis B vaccine (recombinant), adjuvanted, in patients with end-stage renal disease at an urban safety net hospital

PURPOSE

Heplisav-B is a novel recombinant adjuvanted vaccine for hepatitis B virus (HBV) that has been approved as a 2-dose regimen and shown to have similar seroconversion rates in healthy adults as single-antigen HBV vaccines. More data are needed to determine whether similarly high rates of seroconversion and immunity are observed in immunocompromised patient populations such as in patients with end-stage renal disease (ESRD) on hemodialysis.

METHODS

Patients with ESRD who presented for emergency-only hemodialysis and either were HBV vaccine naive or had a hepatitis B surface antibody (anti-HBs) titer of less than 10 IU/mL received 3 standard 20-μg doses of Heplisav-B at week 0, week 4 (±2 weeks), and week 24 (±2 weeks), with anti-HBs titer measured at week 28 (±2 weeks).

RESULTS

Thirty-two patients received at least one dose in the study timeframe, with 24 patients completing the vaccine series and measurement of anti-HBs titer. The mean age of the patients was 46 years, and 58% of patients were male. Of the 24 patients who completed the vaccine series, 20 (83%) seroconverted after the third dose. Three of the 4 patients who did not seroconvert after 3 doses were revaccinated with an additional 20-μg dose, and 2 of the 3 patients had an anti-HBs titer of greater than 10 IU/mL 4 weeks after this dose.

CONCLUSION

Patients with ESRD who received three 20-μg doses of recombinant HBV vaccine had a seroconversion rate of 83%, representing a similar seroconversion rate and fewer doses of vaccine as compared to the standard HBV vaccine regimen for patients with ESRD.

Effectiveness of oral levamisole as an adjuvant to hepatitis B vaccination in healthcare workers non-responsive to previous vaccination: A randomized controlled trial

Background

Healthcare workers are at risk for HBV infection through percutaneous or mucosal contact with infected blood, body secretions, or blood products or via sharps injury. Hepatitis B vaccination, despite immunogenicity, may not induce a proper immune response in 5-10% of the general adult population. Increased immune response in healthcare providers that do not respond properly to conventional hepatitis B vaccination is an important health challenge. Therefore, the aim of the present study was to evaluate the effectiveness of hepatitis B vaccination plus oral levamisole as adjuvant in healthcare providers non-responsive to routine vaccination.

Materials and methods

The healthcare workers that were non-responsive to previous hepatitis B vaccination were enrolled in a double-blind randomized placebo-controlled clinical trial. The participants were then randomized to two groups including hepatitis B vaccination (as a three-dose series on a 0, 1, and 2-month schedule in the deltoid muscle) plus levamisole (levamisole group) and hepatitis B vaccination plus placebo (placebo group) at a 1:1 ratio. The outcome measure was the HBs antibody titer one month after receiving each dose as well as the seroprotection ratio. The side effects were also evaluated in all participants.

Results

In total, 22 subjects finished the trial (11 individual in per group). The median antibody titer one month after receiving the first and third doses increased more in the levamisole group compared to the placebo group but the difference was not significant (p ​= ​0.34, p ​= ​0.66, respectively).The seroprotection ratio after three doses was similarly high in both groups (90.9% in per group). Furthermore, the seroprotection ratio and median antibody titer had no significant correlation with age, sex, BMI, and history of smoking in intervention and control groups (p>0.05). No serious side effects were noted in both groups.

Conclusions

Re-vaccination can boost the immune response in healthcare professionals that were non-responsive to previous vaccination although the mean antibody titer was higher in the levamisole group.

Hepatitis B Vaccination in Advanced Chronic Kidney Disease: A Quality Improvement Project at a Veteran Affairs Chronic Kidney Disease Clinic

Hepatitis B vaccination is recommended in all patients with end-stage kidney disease (ESKD). However, only 50–60% of these patients achieve protective antibody levels if immunized after starting dialysis. Strategies to overcome this low seroconversion rate include a 6-month vaccination schedule starting earlier [chronic kidney disease (CKD) stage 4 and 5] to ensure immunity when patients progress to ESKD. We conducted a quality improvement program to immunize pre-dialysis patients. Patients who were found to have a negative baseline serology with a negative hepatitis B surface antibody level (HBsAb) were offered vaccination on a 6-month schedule (0, 1 and 6 months) with one of two available vaccines within the VA system (Recombivax™ or Engerix™). HBsAb titers were checked 3–4 months later, and titers ≥ 12 mIU/mL were indicative of immunity at VA. Patients who did not seroconvert were offered a repeat schedule of three more doses. We screened 198 patients (187 males and 11 females) with CKD 4 and 5 [glomerular filtration rate (GFR) < 29 mL/min/1.73 m²]. The median age of this cohort was 72 years (range 38–92 years). During the study period of 5 years (2015–2020), 10 patients were excluded since their GFR had improved to more than 30 mL/min/1.73 m², 24 others had baseline immunity and 2 refused vaccination. The hepatitis B vaccination series was not started on 106 patients. Of the remaining 56, 12 patients progressed to ESKD and started dialysis before completion of the vaccination schedule, 6 expired and 1 did not come to clinic in 2020 due to the pandemic. Of the 37 patients who completed the vaccination schedule, 16 achieved seroconversion with adequate HBsAb titers, 10 did not develop immunity despite a second hepatitis B vaccination series, while 11 did not get a second series. Given the low seroconversion rate, albeit in a small cohort, vaccination should be considered in patients with earlier stages of CKD. Other options include studies on FDA approved vaccines of shorter duration. We plan to increase awareness among nephrologists, patients and nursing staff about the importance of achieving immunity against hepatitis B.

Hepatitis B Vaccination Status in Chronic Kidney Disease: Experience at Pakistan Institute of Medical Sciences

Objective To know the status of vaccination against hepatitis B in chronic kidney disease patients, and to see the association of vaccination status with various factors. Materials and Methods A cross-sectional observational study was conducted in the Department of Nephrology, Pakistan Institute of Medical Sciences, Islamabad, from December 2015 to May 2016. Patients reporting in the outpatient department or admitted with the diagnosis of chronic kidney disease, whether on dialysis or not, were included in the study. Patient's information like the status of hepatitis B vaccination, age, gender, socioeconomic status, education and duration of chronic kidney disease were collected on a specially designed proforma. Results A total of 451 patients were included in the study, 57.43% were male and 42.57% were female. Mean age was 43.76±17.12 years. About 69% of the patients were from low socioeconomic class, 31% from the middle or higher middle class. Most of the patients were either uneducated (32.59%) or only had eight years of school education (33.04%). Only 19.9% of patients were vaccinated against hepatitis B virus. Conclusion Status of vaccination against hepatitis B virus in chronic kidney disease patients is not satisfactory. It is strongly associated with socioeconomic class.

Characterization of hepatitis B virus in Amerindian children and mothers from Amazonas State, Colombia

BACKGROUND

Hepatitis B Virus (HBV) infection is a worldwide public health problem. In the 1980's a highly effective and safe vaccine against HBV was developed, although breakthrough infection still occasionally occurs because of the emergence of escape mutants. The aim of this study was to identify HBV genotypes and escape mutants in children and their mothers in Amerindian communities of the Amazonas State, Southern Colombia.

METHODS

Blood specimens collected from children and mothers belonging to 37 Amerindian communities in Amazonas state, were screened for HBsAg and anti-HBc using ELISA. The partial region containing the S ORF was amplified by nested PCR, and amplicons were sequenced. The phylogenetic analysis was performed using the MEGA 5.05 software.

RESULTS

Forty-six children (46/1275, 3.6%) and one hundred and seventy-seven mothers (177/572, 30.9%) were tested positive for the anti-HBc serological marker. Among them, 190 samples were tested for viral genome detection; 8.3% (2/31) serum samples obtained from children and 3.1% (5/159) from mothers were positive for the ORF S PCR. The predominant HBV genotype in the study population was F, subgenotype F1b; in addition, subgenotype F1a and genotype A were also characterized. Two HBV escape mutants were identified, G145R, reported worldwide, and W156*; this stop codon was identified in a child with occult HBV infection. Other mutations were found, L109R and G130E, located in critical positions of the HBsAg sequence.

CONCLUSIONS

This study aimed to characterize the HBV genotype F, subgenotypes F1b and F1a, and genotype A in Amerindian communities and for the first time escape mutants in Colombia. Further investigations are necessary to elucidate the frequency and the epidemiological impact of the escape mutants in the country.