Immunogenicity and safety of an investigational hepatitis B vaccine with a Toll-like receptor 9 agonist adjuvant (HBsAg-1018) compared to a licensed hepatitis B vaccine in healthy adults 40-70 years of age. Vaccine. 2013;31:5300-5305. [PMID: 23727002 DOI: 10.1016/j.vaccine.2013.05.068]

Post-marketing safety study to evaluate pregnancy outcomes among recipients of hepatitis B vaccines

HepB-CpG is a licensed adjuvanted two-dose hepatitis B vaccine for adults, with limited data on exposure during pregnancy. We assessed the risk of pregnancy outcomes among individuals who received HepB-CpG or the 3-dose HepB-alum vaccine ≤28 d prior to conception or during pregnancy at Kaiser Permanente Southern California (KPSC). The pregnancy cohort included KPSC members aged ≥18 y who received ≥1 dose of hepatitis B vaccine (HepB-CpG or HepB-alum) at KPSC outpatient family or internal medicine departments from August 2018 to November 2020. We followed these individuals through electronic health records from the vaccination date until the end of pregnancy, KPSC health plan disenrollment, or death, whichever came first. Among 81 and 125 eligible individuals who received HepB-CpG and HepB-alum, respectively, live births occurred in 84% and 74%, spontaneous abortion occurred in 7% and 17% (adjusted relative risk [aRR] 0.40, 95% CI: 0.16-1.00), and preterm birth occurred in 15% and 14% of liveborn infants (aRR 0.97, 95% CI 0.47-1.99). No major birth defects were identified through 6 months of age. The study found no evidence of adverse pregnancy outcomes for recipients of HepB-CpG in comparison to HepB-alum.

Phase 1 trial of an investigational Tdap booster vaccine with CpG 1018 adjuvant compared with Boostrix in healthy adults and adolescents

This phase 1 trial assessed the safety and immunogenicity of an investigational tetanus/diphtheria/acellular pertussis vaccine combined with CpG 1018 adjuvant 1500 μg (Tdap-1018 1500 μg) or 3000 μg (Tdap-1018 3000 μg) in adults and adolescents. In this randomized, active-controlled, multicenter, dose-escalation trial, healthy participants aged 10 to 22 years received 1 dose of Tdap-1018 1500 μg, Tdap-1018 3000 μg, or Boostrix. Geometric mean concentrations (GMCs) and booster response rates (BRRs) for antibodies against pertussis (pertussis toxin, filamentous hemagglutinin, pertactin), tetanus, and diphtheria antigens, and neutralizing antibodies against pertussis toxin were assessed 4 weeks after vaccination. Safety and tolerability were assessed for solicited post-injection reactions within 7 days after vaccination and unsolicited adverse events up to 12 weeks after vaccination. Of 117 enrolled participants, 80 adults (92%) and 30 adolescents (100%) completed the study. Both Tdap-1018 formulations were generally well tolerated, with no vaccine-related serious adverse events. Frequency and severity in post-injection reactions after Tdap-1018 administration were similar to Boostrix except for higher proportions of moderate pain for Tdap-1018. In adults at week 4, ratio of GMCs and BRRs for all antigens in the 3000-μg group were similar to or higher than Boostrix, with significantly higher GMC ratios for anti-pertussis toxin (2.1 [1.5-3.0]) and anti-tetanus (1.8 [1.1-2.9]) and significantly higher BRRs for anti-pertussis toxin (difference [95% CI]: 34.5% [13.4-54.6]), anti-pertactin (19.2% [4.4-38.1]), and anti-tetanus (30.0% [3.6-52.7]) antibodies. For adolescents, in the 3000-μg group, ratio of GMCs and BRRs were similar to or higher than Boostrix for all antigens. Both Tdap-1018 formulations showed acceptable safety and tolerability profiles. Tdap-1018 3000 μg induced similar or higher immune responses than Boostrix. ACTRN12620001177943 (Australian New Zealand Clinical Trials Registry; https://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=ACTRN12620001177943p).

Dose-dependent regulation of immune memory responses against HIV by saponin monophosphoryl lipid A nanoparticle adjuvant

The induction of durable protective immune responses is the main goal of prophylactic vaccines, and adjuvants play an important role as drivers of such responses. Despite advances in vaccine strategies, a safe and effective HIV vaccine remains a significant challenge. The use of an appropriate adjuvant is crucial to the success of HIV vaccines. Here we assessed the saponin/MPLA nanoparticle (SMNP) adjuvant with an HIV envelope (Env) trimer, evaluating the safety and impact of multiple variables including adjuvant dose (16-fold dose range), immunization route, and adjuvant composition on the establishment of Env-specific memory T and B cell responses (T Mem and B Mem ) and long-lived plasma cells in non-human primates. Robust B Mem were detected in all groups, but a 6-fold increase was observed in the highest SMNP dose group vs. the lowest dose group. Similarly, stronger vaccine responses were induced in the highest SMNP dose for CD40L + OX40 + CD4 T Mem (11-fold), IFNγ + CD4 T Mem (15-fold), IL21 + CD4 T Mem (9-fold), circulating T FH (3.6-fold), bone marrow plasma cells (7-fold), and binding IgG (1.3-fold). Substantial tier-2 neutralizing antibodies were only observed in the higher SMNP dose groups. These investigations highlight the dose-dependent potency of SMNP in non-human primates, which are relevant for human use and next-generation vaccines.

Non-coding RNAs to treat vascular smooth muscle cell dysfunction

Vascular smooth muscle cell (vSMC) dysfunction is a critical contributor to cardiovascular diseases, including atherosclerosis, restenosis and vein graft failure. Recent advances have unveiled a fascinating range of non-coding RNAs (ncRNAs) that play a pivotal role in regulating vSMC function. This review aims to provide an in-depth analysis of the mechanisms underlying vSMC dysfunction and the therapeutic potential of various ncRNAs in mitigating this dysfunction, either preventing or reversing it. We explore the intricate interplay of microRNAs, long-non-coding RNAs and circular RNAs, shedding light on their roles in regulating key signalling pathways associated with vSMC dysfunction. We also discuss the prospects and challenges associated with developing ncRNA-based therapies for this prevalent type of cardiovascular pathology.

Adjuvants in COVID-19 vaccines: innocent bystanders or culpable abettors for stirring up COVID-heart syndrome

COVID-19 infection is a multi-system clinical disorder that was associated with increased morbidity and mortality. Even though antiviral therapies such as Remdesvir offered modest efficacy in reducing the mortality and morbidity, they were not efficacious in reducing the risk of future infections. So, FDA approved COVID-19 vaccines which are widely administered in the general population worldwide. These COVID-19 vaccines offered a safety net against future infections and re-infections. Most of these vaccines contain inactivated virus or spike protein mRNA that are primarily responsible for inducing innate and adaptive immunity. These vaccines were also formulated to contain supplementary adjuvants that are beneficial in boosting the immune response. During the pandemic, clinicians all over the world witnessed an uprise in the incidence and prevalence of cardiovascular diseases (COVID-Heart Syndrome) in patients with and without cardiovascular risk factors. Clinical researchers were not certain about the underlying reason for the upsurge of cardiovascular disorders with some blaming them on COVID-19 infections while others blaming them on COVID-19 vaccines. Based on the literature review, we hypothesize that adjuvants included in the COVID-19 vaccines are the real culprits for causation of cardiovascular disorders. Operation of various pathological signaling events under the influence of these adjuvants including autoimmunity, bystander effect, direct toxicity, anti-phospholipid syndrome (APS), anaphylaxis, hypersensitivity, genetic susceptibility, epitope spreading, and anti-idiotypic antibodies were partially responsible for stirring up the onset of cardiovascular disorders. With these mechanisms in place, a minor contribution from COVID-19 virus itself cannot be ruled out. With that being said, we strongly advocate for careful selection of vaccine adjuvants included in COVID-19 vaccines so that future adverse cardiac disorders can be averted.

Efficacy and safety of hepatitis B vaccine: an umbrella review of meta-analyses

BACKGROUND

There is a lack of synthesis of literature to determine hepatitis B vaccine (HepB) strategies for hepatitis B virus (HBV) supported by quality evidence. We aimed to explore the efficacy and safety of HepB strategies among people with different characteristics.

RESEARCH DESIGN AND METHODS

PubMed, Cochrane Library, Embase, and Web of Science were searched for meta-analyses comparing the efficacy and safety of HepB up to July 2023.

RESULTS

Twenty-one meta-analyses comparing 83 associations were included, with 16 high quality, 4 moderate, and 1 low quality assessed by AMSTAR 2. Highly suggestive evidence supports HepB booster and HepB with 1018 adjuvant (HBsAg-1018) for improved seroprotection, and targeted and universal HepB vaccination reduced HBV infection Suggestive evidence indicated that targeted vaccination decreased the rate of hepatitis B surface antibody positivity and booster doses increased seroprotection in people aged 10-20. Weak evidence suggests potential local/systemic reaction risk with nucleotide analogs or HBsAg-1018. Convincing evidence shows HLA-DPB1*04:01 and DPB1*04:02 increased, while DPB1*05:01 decreased, hepatitis B antibody response. Obesity may reduce HepB seroprotection, as highly suggested.

CONCLUSION

Targeted vaccination could effectively reduce HBV infection, and adjuvant and booster vaccinations enhance seroprotection without significant reaction. Factors such as obesity and genetic polymorphisms may affect the efficacy.

Strategies for Hepatitis B Virus Prevention in People Living with HIV

PURPOSE OF REVIEW

Coinfection with HIV and hepatitis B virus (HBV) is common owing to shared routes of transmission, and persons with HIV-HBV coinfection experience an accelerated progression of liver disease. Despite the widespread availability of HBV vaccination, rates of seroprotection in people living with HIV (PLWH) have historically been low. In this article, we review strategies in HBV prevention among PLWH, focusing specifically on updates in HBV vaccination and chemoprophylaxis.

RECENT FINDINGS

Vaccination remains the hallmark of HBV prevention, and recent studies suggest that a double dose of HBV vaccine and Heplisav-B can improve rates of seroprotection among PLWH. The use of tenofovir-containing antiretroviral therapy (ART) has similarly been shown to provide some HBV protection in PLWH; however, this protection can be lost when switching to newer tenofovir-sparing regimens, including long-acting injectables. All HBV-susceptible persons with HIV should be vaccinated against HBV, regardless of ART regimen and CD4 count.

Worth a Pound of Cure? Emerging Strategies and Challenges in Cancer Immunoprevention

Cancer immunoprevention applies immunologic approaches such as vaccines to prevent, rather than to treat or cure, cancer. Despite limited success in the treatment of advanced disease, the development of cancer vaccines to intercept premalignant states is a promising area of current research. These efforts are supported by the rationale that vaccination in the premalignant setting is less susceptible to mechanisms of immune evasion compared with established cancer. Prophylactic vaccines have already been developed for a minority of cancers mediated by oncogenic viruses (e.g., hepatitis B and human papillomavirus). Extending the use of preventive vaccines to non-virally driven malignancies remains an unmet need to address the rising global burden of cancer. This review provides a broad overview of clinical trials in cancer immunoprevention with an emphasis on emerging vaccine targets and delivery platforms, translational challenges, and future directions.

Immunogenicity and Safety of Hepatitis B Virus (HBV) Vaccine With a Toll-Like Receptor 9 Agonist Adjuvant in HBV Vaccine-Naïve People With Human Immunodeficiency Virus

In this international, multicenter open-label study (ACTG A5379) of HepB-CpG vaccine in people with human immunodeficiency virus (HIV) without prior hepatitis B virus (HBV) vaccination, all 68 participants achieved HBV seroprotective titers after the 3-dose series in the primary analysis. No unexpected safety issues were observed.

Preventing Hepatitis B Virus Infection Among U.S. Military Personnel: Potential Impact of a 2-Dose Versus 3-Dose Vaccine on Medical Readiness

INTRODUCTION

Hepatitis B, a major public health issue worldwide, has been associated with serious clinical outcomes. Military personnel are at particular risk for hepatitis B, such that hepatitis B vaccination is part of the accession process for new recruits. Although lost time costs and medical cost avoidance have been used by the U.S. Military to guide their decision-making protocols, this has not been applied to hepatitis B vaccination costs. Herein, a decision-analytic model is used to compare the effective vaccine protection rates and vaccine and operational costs of 2-dose versus 3-dose hepatitis B vaccine regimens in a population of recruits from the U.S. Marine Corps Recruit Depot, Parris Island.

METHODS

A decision-analytic model was developed to assess the expected levels of adherence, seroprotection, and vaccination and operational costs of a cohort of recruits vaccinated with either a 2-dose (HepB-CpG) vaccine for those eligible (scenario 1) or a 3-dose (HepB-Alum) vaccine (scenario 2). De-identified data from 23,004 recruits at the Marine Corps Recruit Depot, Parris Island, in 2018 and 2019 were used to provide real-world data on age distribution and vaccination status. Other inputs included published data on adherence for hepatitis B vaccines and seroprotection rates for HepB-CpG and HepB-Alum in relation to the number of doses received. Costs included direct medical costs of the hepatitis B vaccination and operational costs such as missed training time.

RESULTS

After receipt of two vaccine doses, 92% of recruits in scenario 1 (HepB-CpG group) were expected to be protected against hepatitis B within 1 month of receiving the second dose, compared with 24% of recruits in scenario 2 (HepB-Alum group), leaving 76% of Marine recruits unprotected if using HepB-Alum during the intervening 5-month period between doses 2 and 3. Over the study period, HepB-CpG was estimated to provide cost savings of $744,509 (17.3% cost reduction) compared with HepB-Alum, with the cost of missed training time being the most influential driver of the cost difference between the two vaccination schedules.

CONCLUSIONS

Findings from this model suggest that vaccination with the 2-dose HepB-CpG vaccine may provide earlier and higher protection against hepatitis B compared with the 3-dose vaccine (HepB-Alum). A 2-dose vaccination strategy incorporated as part of individual medical readiness has the potential to not only increase protection but also confer economic savings among military recruits at risk for hepatitis B infection.

Observational Study Evaluating the Seroprotection of HepB-alum Vaccine and HepB-CpG Vaccine in People With HIV

Background

Hepatitis B virus (HBV) vaccine seroprotection rates with conventional aluminum adjuvanted recombinant HBV vaccines, Engerix-B (HepB-alum) vaccine, among people with HIV (PWH) are varied. Heplisav-B (HepB-CpG) vaccine, a novel adjuvanted recombinant HBV vaccine, has shown higher seroprotection rates in immunocompetent patients but is not well studied in PWH. There are no published studies comparing seroprotection rates between HepB-alum and HepB-CpG in PWH. This study aims to evaluate and compare the seroprotection incidence of HepB-alum vs HepB-CpG in PWH at least 18 years of age.

Methods

This retrospective, observational cohort study included adults diagnosed with HIV who received a complete series of HepB-alum or HepB-CpG at a community health center in Phoenix, Arizona. Patients had a hepatitis B surface antibody <10 IU/L at the time of the first vaccine dose. The primary outcome was a comparison of seroconversion incidence between HepB-CpG and HepB-alum. Secondary outcomes included identifying factors associated with likelihood of response to HBV vaccination.

Results

A total of 120 patients were included in this study, 59 in the HepB-alum cohort and 61 in the HepB-CpG cohort. In the HepB-alum cohort, 57.6% achieved seroconversion, compared with 93.4% in the HepB-CpG cohort (P < .001). Those without diabetes were more likely to have response to a vaccine.

Conclusions

Among PWH at a single community health center, HepB-CpG provided a statistically higher incidence of seroprotection against HBV compared with HepB-alum.

Nasal vaccines: solutions for respiratory infectious diseases

Nasal vaccines induce pathogen-specific dual protective immunity at mucosal surfaces and systemically throughout the body. Consequently, nasal vaccines both prevent pathogen invasion and reduce disease severity. Because of these features, nasal vaccines are considered to be a next-generation tool for preventing respiratory infectious diseases, including COVID-19. However, nasal vaccines must overcome key safety concerns given the anatomic proximity of the central nervous system (CNS) via the olfactory bulbs which lie next to the nasal cavity. This review summarizes current efforts to develop safe and effective nasal vaccines and delivery systems, as well as their clinical applications for the prevention of respiratory infections. We also discuss various concerns regarding the safety of nasal vaccines and introduce a system for evaluating them.

Recent Advances in Protective Vaccines against Hepatitis Viruses: A Narrative Review

Vaccination has been confirmed to be the safest and, sometimes, the only tool of defense against threats from infectious diseases. The successful history of vaccination is evident in the control of serious viral infections, such as smallpox and polio. Viruses that infect human livers are known as hepatitis viruses and are classified into five major types from A to E, alphabetically. Although infection with hepatitis A virus (HAV) is known to be self-resolving after rest and symptomatic treatment, there were 7134 deaths from HAV worldwide in 2016. In 2019, hepatitis B virus (HBV) and hepatitis C virus (HCV) resulted in an estimated 820,000 and 290,000 deaths, respectively. Hepatitis delta virus (HDV) is a satellite virus that depends on HBV for producing its infectious particles in order to spread. The combination of HDV and HBV infection is considered the most severe form of chronic viral hepatitis. Hepatitis E virus (HEV) is another orally transmitted virus, common in low- and middle-income countries. In 2015, it caused 44,000 deaths worldwide. Safe and effective vaccines are already available to prevent hepatitis A and B. Here, we review the recent advances in protective vaccines against the five major hepatitis viruses.

PreHevbrio: the first approved 3-antigen hepatitis B vaccine

INTRODUCTION

Hepatitis B remains a major cause of death and morbidity worldwide. Universal childhood immunization programs have been very successful, but many adults remain unprotected or are not optimally protected. PreHevbrio [Hepatitis B Vaccine (recombinant)] is a highly immunogenic 3-antigen (S/pre-S1/pre-S2) hepatitis B vaccine (3A-HBV) that recently received marketing authorization in the United States (2021), the European Union, United Kingdom (2022 - brand name PreHevbri), and Canada (2022- brand name PreHevbrio) for the prevention of infection caused by all known subtypes of the hepatitis B virus and the delta virus in adults 18 years and older.

AREAS COVERED

This review details the development of 3A-HBV and summarizes the results of the phase 3 clinical trials that support its immunogenicity and safety in adults.

EXPERT OPINION

3A-HBV is highly immunogenic in adults of all ages, including older adults and subgroups that respond sub-optimally to conventional single S-antigen hepatitis B vaccines (1A-HBV), such as those with obesity, type 2 diabetes, and smokers. 3A-HBV provides higher seroprotection rates after each vaccination compared to conventional 1A-HBV vaccines, allowing for more rapid protection. The higher overall immunogenicity is also reflected in more durable seroprotection years after vaccination, as supported by a follow-up study to one of the phase 3 studies.

Stabilized HIV-1 envelope immunization induces neutralizing antibodies to the CD4bs and protects macaques against mucosal infection

A successful HIV-1 vaccine will require induction of a polyclonal neutralizing antibody (nAb) response, yet vaccine-mediated induction of such a response in primates remains a challenge. We found that a stabilized HIV-1 CH505 envelope (Env) trimer formulated with a Toll-like receptor 7/8 agonist induced potent HIV-1 polyclonal nAbs that correlated with protection from homologous simian-human immunodeficiency virus (SHIV) infection. The serum dilution that neutralized 50% of virus replication (ID50 titer) required to protect 90% of macaques was 1:364 against the challenge virus grown in primary rhesus CD4+ T cells. Structural analyses of vaccine-induced nAbs demonstrated targeting of the Env CD4 binding site or the N156 glycan and the third variable loop base. Autologous nAb specificities similar to those elicited in macaques by vaccination were isolated from the human living with HIV from which the CH505 Env immunogen was derived. CH505 viral isolates were isolated that mutated the V1 to escape both the infection-induced and vaccine-induced antibodies. These results define the specificities of a vaccine-induced nAb response and the protective titers of HIV-1 vaccine-induced nAbs required to protect nonhuman primates from low-dose mucosal challenge by SHIVs bearing a primary transmitted/founder Env.

Insights into induction of the immune response by the hepatitis B vaccine

After more than four decades of hepatitis B virus (HBV) vaccine implementation, its safety and efficacy in preventing HBV infection have been proven and several milestones have been achieved. Most countries have included HBV immunization schedules in their health policies and progress has been made regarding universalization of the first HBV vaccine dose at birth. All of these actions have significantly contributed to reducing both the incidence of HBV infection and its related complications. However, there are still many drawbacks to overcome. The main concerns are the deficient coverage rate of the dose at birth and the large adult population that has not been reached timely by universal immunization. Additionally, the current most widely used second-generation vaccines do not induce protective immunity in 5% to 10% of the population, particularly in people over 40-years-old, obese (body mass index > 25 kg/m²), heavy smokers, and patients undergoing dialysis or infection with human immunodeficiency virus. Recently developed and approved novel vaccine formulations using more potent adjuvants or multiple antigens have shown better performance, particularly in difficult settings. These advances re-launch the expectations of achieving the World Health Organization’s objective of completing hepatitis control by 2030.

A Precision Adjuvant Approach to Enhance Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Vaccines Optimized for Immunologically Distinct Vulnerable Populations

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has caused significant mortality, especially among older adults whose distinct immune system reflects immunosenescence. Multiple SARS-CoV-2 vaccines have received emergency use authorization and/or licensure from the US Food and Drug Administration and throughout the world. However, their deployment has heighted significant limitations, such by age-dependent immunogenicity, requirements for multiple vaccine doses, refrigeration infrastructure that is not universally available, as well as waning immunity. Thus, there was, and continues to be a need for continued innovation during the pandemic given the desire for dose-sparing, formulations stable at more readily achievable temperatures, need for robust immunogenicity in vulnerable populations, and development of safe and effective pediatric vaccines. In this context, optimal SARS-CoV-2 vaccines may ultimately rely on inclusion of adjuvants as they can potentially enhance protection of vulnerable populations and provide dose-sparing effects enabling single shot protection.

Trends in Adult and Elderly Vaccination: Focus on Vaccination Practices in Tunisia and Morocco

Vaccine preventable diseases (VPDs) are a prevailing concern among the adult population, despite availability of vaccines. Unlike pediatric vaccination programs, adult vaccination programs lack the required reach, initiative, and awareness. Clinical studies and real-world data have proven that vaccines effectively reduce the disease burden of VPDs and increase life expectancy. In Tunisia and Morocco, the national immunization program (NIP) focuses more on pediatric vaccination and have limited vaccination programs for adults. However, some vaccination campaigns targeting adults are organized. For example, influenza vaccination campaigns prioritizing at risk adults which includes healthcare professionals, elderly, and patients with comorbidities. Women of childbearing age who have never been vaccinated or whose information is uncertain are recommended to receive tetanus vaccination. Tunisia NIP recommends rubella vaccine mainly for women of childbearing age, while in Morocco, national vaccination campaigns were organized for girls and women (up to 24 years of age) to eliminate rubella. Further, travelers from both countries are recommended to follow all requirements and recommendations in the travel destination. The objective of this manuscript is to provide an overview of the global disease burden of common VPDs including (but not limited to) meningococcal diseases, pneumococcal diseases, hepatitis, and influenza. The review also provides an overview of clinical data and guidelines/recommendations on adult vaccination practices, with special focus on Tunisia and Morocco. Some European and North American countries have concrete recommendations and strategies for adult vaccination to keep the VPDs in check. In Morocco and Tunisia, although, there are sporadic adult vaccination initiatives, the efforts still need upscaling and endorsements to boost vaccination awareness and uptake. There is a need to strengthen strategies in both countries to understand the disease burden and spread awareness. Additional studies are needed to generate economic evidence to support cost-effectiveness of vaccines. Integration of private and public healthcare systems may further improve vaccination uptake in adults.

An Evidence-based Practical Guide to Vaccination for Hepatitis B Virus

The hepatitis B virus (HBV) is highly infectious, with over 292 million chronically infected people worldwide and up to 2.4 million in the United States. Following infection, clinically silent liver damage can ensue, but symptoms or signs of advanced disease, including cirrhosis and hepatocellular carcinoma, can take decades to emerge. HBV has the heaviest public health burden of all hepatitis viruses and has now surpassed other major communicable diseases (eg, HIV, diarrheal disease, malaria, tuberculosis) as a leading cause of death globally. Preventing transmission is essential, and efforts are in place to reinforce screening, vaccination, and routine follow-up. Three safe and effective vaccines are available in the United States and other countries for HBV prevention, and the benefits of vaccination in preventing infection and its sequelae have been substantiated. For the first time in over 25 years, a new Food and Drug Administration-approved vaccine is available that offers a high degree of immunogenicity after 2, rather than 3, injections. Persistent challenges include the underutilization of vaccination, choice of vaccine, incomplete vaccinations, varying needs in different populations, management of nonresponders or those with undocumented or incompletely documented vaccination courses, and questions about whether and when booster injections may be needed. A panel of US academic hepatologists with expertise and experience in preventing and managing HBV infection have collaborated to write this practical clinical paper intended to guide clinicians in vaccinating for HBV and address questions that regularly arise in the clinic.

Safety and immunogenicity of HepB-CpG in women with documented pregnancies post-vaccination: A retrospective chart review

BACKGROUND

There are currently no published data on the use of HepB-CpG (HEPLISAV-B®) during pregnancy or in women with documented pregnancies in the post-vaccination period. We aimed to evaluate data from the clinical development program of HepB-CpG in women who became pregnant during study participation and follow up.

METHODS

We identified all study participants in the HepB-CpG pivotal pre-licensure clinical trials that had documented pregnancies during study follow up. We measured immunogenicity among study participants in the HepB-CpG (Heplisav-B®) arm compared to the HepB-alum (Engerix-B®) arm of the studies by comparing seroprotection rates (SPRs; anti-HBs ≥ 10 mIU/mL) and geometric mean concentrations (GMCs) of anti-HBs, obtained with FDA approved anti-HBsAg antibody assays at prespecified time points up to 28 weeks of follow up. Pregnancy outcomes were ascertained by chart review of extracted medical records of study participants.

RESULTS

We identified 40 documented pregnancies in the HepB-CpG arm and 19 documented pregnancies in the HepB-alum arm. Among subjects with documentation of seroprotection rates, 97.2% (95% CI 85.5-99.9) were seroprotected in the HepB-CpG arm and 66.7% (95% CI 41.0-86.7) were seroprotected in the HepB-alum arm. In the HepB-CpG arm, thirty-six study participants from the pivotal trials had reported pregnancy outcomes, the majority, 21/36 (58%) had a healthy term delivery, with 3/36 (8%) with spontaneous abortions, 1/36 (3%) congenital anomaly, and 2/36 (6%) had preterm birth. In the HepB-alum arm, 10/17 (59%) had healthy term deliveries, with 2/17 (12%) had spontaneous abortions and 1/17 (6%) had congenital anomaly.

CONCLUSIONS

These limited data suggest that HepB-CpG is immunogenic in women who become pregnant after vaccination, and pregnancy outcomes appear to be similar to women who received HepB-alum prior to pregnancy. These results need to be further verified with larger prospective studies with HBV vaccine administration during pregnancy.

Association Between 2-Dose vs 3-Dose Hepatitis B Vaccine and Acute Myocardial Infarction

Importance

The 2-dose hepatitis B vaccine with a cytosine phosphoguanine adjuvant (HepB-CpG vaccine; Heplisav-B) generated higher seroprotection in prelicensure trials than did a 3-dose hepatitis B vaccine with an aluminum hydroxide adjuvant (HepB-alum vaccine; Engerix-B). However, in 1 trial, a higher number of acute myocardial infarction (MI) events were observed among those who received the HepB-CpG vaccine than among those who received the HepB-alum vaccine, an outcome requiring further study.

Objective

To compare the rate of acute MI between recipients of HepB-CpG vaccine and HepB-alum vaccine.

Design, Setting, and Participants

This prospective cohort noninferiority study was conducted at Kaiser Permanente Southern California (KPSC), an integrated health care system with 15 medical centers and approximately 4.7 million members. The study included 69 625 adults not undergoing dialysis who received at least 1 dose of a hepatitis B vaccine in either family medicine or internal medicine departments at KPSC from August 7, 2018, to October 31, 2019 (November 30, 2020, final follow-up).

Exposures

Receipt of HepB-CpG vaccine vs HepB-alum vaccine. The first dose during the study period was the index dose.

Main Outcomes and Measures

Individuals were followed up for 13 months after the index dose for occurrence of type 1 acute MI. Potential events were identified using diagnosis codes and adjudicated by cardiologists. The adjusted hazard ratio (HR) of acute MI was estimated comparing recipients of HepB-CpG vaccine with recipients of HepB-alum vaccine, with inverse probability of treatment weighting (IPTW) to adjust for demographic and clinical characteristics. The upper limit of the 1-sided 97.5% CI was compared with a noninferiority margin of 2.

Results

Of the 31 183 recipients of HepB-CpG vaccine (median age, 49 years; IQR, 38-56 years), 51.2% (n = 15 965) were men, and 52.7% (n = 16 423) were Hispanic. Of the 38 442 recipients of HepB-alum (median age, 49 years; IQR, 39-56 years), 50.8% (19 533) were men, and 47.1% (n = 18 125) were Hispanic. Characteristics were well-balanced between vaccine groups after IPTW. Fifty-two type 1 acute MI events were confirmed among recipients of HepB-CpG vaccine for a rate of 1.67 per 1000-person-years, and 71 type 1 acute MI events were confirmed among recipients of HepB-alum vaccine for a rate of 1.86 per 1000 person-years (absolute rate difference, -0.19 [95% CI, -0.82 to 0.44]; adjusted HR, 0.92 [1-sided 97.5% CI, ∞ to 1.32], which was below the noninferiority margin; P < .001 for noninferiority).

Conclusions and Relevance

In this cohort study, receipt of HepB-CpG vaccine compared with HepB-alum vaccine did not meet the statistical criterion for increased risk of acute myocardial infarction.

Safety, immunogenicity, and protection provided by unadjuvanted and adjuvanted formulations of a recombinant plant-derived virus-like particle vaccine candidate for COVID-19 in nonhuman primates

Although antivirals are important tools to control severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, effective vaccines are essential to control the current coronavirus disease 2019 (COVID-19) pandemic. Plant-derived virus-like particle (VLP) vaccine candidates have previously demonstrated immunogenicity and efficacy against influenza. Here, we report the immunogenicity and protection induced in rhesus macaques by intramuscular injections of a VLP bearing a SARS-CoV-2 spike protein (CoVLP) vaccine candidate formulated with or without Adjuvant System 03 (AS03) or cytidine-phospho-guanosine (CpG) 1018. Although a single dose of the unadjuvanted CoVLP vaccine candidate stimulated humoral and cell-mediated immune responses, booster immunization (at 28 days after priming) and adjuvant administration significantly improved both responses, with higher immunogenicity and protection provided by the AS03-adjuvanted CoVLP. Fifteen micrograms of CoVLP adjuvanted with AS03 induced a polyfunctional interleukin-2 (IL-2)-driven response and IL-4 expression in CD4 T cells. Animals were challenged by multiple routes (i.e., intratracheal, intranasal, and ocular) with a total viral dose of 106 plaque-forming units of SARS-CoV-2. Lower viral replication in nasal swabs and bronchoalveolar lavage fluid (BALF) as well as fewer SARS-CoV-2-infected cells and immune cell infiltrates in the lungs concomitant with reduced levels of proinflammatory cytokines and chemotactic factors in the BALF were observed in animals immunized with the CoVLP adjuvanted with AS03. No clinical, pathologic, or virologic evidence of vaccine-associated enhanced disease was observed in vaccinated animals. The CoVLP adjuvanted with AS03 was therefore selected for vaccine development and clinical trials.

Developments in Vaccine Adjuvants

Vaccines, including subunit, recombinant, and conjugate vaccines, require the use of an immunostimulator/adjuvant for maximum efficacy. Adjuvants not only enhance the strength and longevity of immune responses but may also influence the type of response. In this chapter, we review the adjuvants that are available for use in human vaccines, such as alum, MF59, AS03, and AS01. We extensively discuss their composition, characteristics, mechanism of action, and effects on the immune system. Additionally, we summarize recent trends in adjuvant discovery, providing a brief overview of saponins, TLRs agonists, polysaccharides, nanoparticles, cytokines, and mucosal adjuvants.

Serological response with Heplisav-B® in prior Hepatitis B vaccine non-responders living with HIV

BACKGROUND

As people living with HIV (PLWH) are at risk for contracting Hepatitis B Virus (HBV), they should be screened for HBV and vaccinated if not immune. Seroconversion rates in PLWH receiving traditional recombinant HBV vaccines (Engerix-B® and Recombivax-HB®) have historically been low with at most 70% achieving immunity. In 2017, a recombinant, adjuvanted HBV vaccine (Heplisav-B®) was approved for use in HIV-negative patients. Heplisav-B® has shown superior seroprotection in this population compared to Engerix-B® and Recombivax-HB®, as well as interim analysis showing higher seropositivity rates in patients undergoing dialysis. However, its efficacy in PLWH is currently unknown. This study evaluates the rate of seroconversion following Heplisav-B® administration in PLWH with previous HBV vaccination failure.

METHODS

Retrospective, cross-sectional study at The Brooklyn Hospital Center's HIV primary care clinic in Brooklyn, NY. HIV-positive adults who received at least two doses of Heplisav-B® and had previously failed to seroconvert after vaccination with Engerix-B® or Recombivax-HB® were included. The primary outcome is the percentage of PLWH who became seropositive following Heplisav-B®.

RESULTS

A total of 67 patients met the inclusion criteria. Twenty-five (37.3%) PLWH had failed at least 2 courses of recombinant vaccines. Fifty-eight (86.6%) PLWH became seropositive (Anti-HBs > 10 mIU/mL) at least two months after completing Heplisav-B®. For the 9 (13.4%) patients that did not develop immunity, 3 (33%) had a detectable HIV RNA and 3 (33%) had a CD4 count < 200 cells/uL³.

CONCLUSIONS

Heplisav-B® was highly effective in achieving immunity to HBV in PLWH who failed non-adjuvanted recombinant vaccines.

Immunogenicity and safety of HBAI20 Hepatitis B vaccine in non-responders: Double-blinded, randomised, controlled phase 2 trial

BACKGROUND & AIMS

Approximately 5%-10% of the general population respond inadequately to licensed recombinant hepatitis B vaccines. We assessed the immunogenicity and safety of a new HBAI20 vaccine, consisting of a new AI20 adjuvant (20-µg recombinant human IL-2 attached to 20-µg aluminium hydroxide) in combination with HBVaxPro®-10 µg.

METHODS

In a double-blinded, randomised, controlled phase 2 trial, 18- to 59-year-old healthy non-responders (titre <10 mIU/ml after three or more doses of hepatitis B vaccine) were assigned (3:1 ratio) to receive either HBAI20 vaccine or HBVaxPro®-10 µg in a 0, 1 and 2-month schedule. The primary outcome was seroprotection (titre ≥ 10 mIU/ml) measured 1-3 months following the third vaccination.

RESULTS

A total of 133 participants were randomised to receive either HBAI20 vaccine (n = 101) or HBVaxPro®-10 µg (n = 32). In the modified intention-to-treat analysis, the seroprotection rate after the third vaccination was 92.0% (80/87) in the HBAI20 group and 79.3% (23/29) in the HBVaxPro®-10-µg group, P = .068. Using a generalised linear mixed model to adjust for stratification factors, a higher odds of seroprotection with HBAI20 vaccine was shown (adjusted odds ratio = 3.48, P = .028). Frequency of mild and moderate local adverse events was greater in the HBAI20 group than in the HBVaxPro®-10 µg. Rates of severe local adverse events and systemic adverse events were low and similar in both groups.

CONCLUSIONS

In this group of hepatitis B vaccine non-responders, the HBAI20 vaccine demonstrated a higher seroprotection rate when adjusting for stratification factors and a similar safety profile compared to the licensed recombinant HBVaxPro®-10 µg.

Considerations for estimating real-world outcomes and value in vaccination: A case study with adult hepatitis B virus vaccination

BACKGROUND

In the absence of field efficacy studies, estimating the real-world effectiveness of vaccines may consider immunogenicity from randomized controlled clinical trials and real-world adherence. Combining seroprotection rates (SPRs) with regimen completion rates gives an estimate of an effective vaccine protection rate (eVPR), which can be leveraged to evaluate real-world cost-effectiveness by linking it with vaccine costs to estimate the cost-per-protected patient (CPP).

METHODS

This study evaluated eVPR and CPP as estimates of vaccine clinical- and cost-effectiveness of two-dose (HepB-CpG) and three-dose (HepB-Alum) hepatitis B virus (HBV) vaccines in the general adult population and a subpopulation with diabetes mellitus. eVPR was calculated from head-to-head SPR data from phase 3 clinical trials directly comparing HepB-CpG and HepB-Alum vaccine regimens and real-world head-to-head adherence data. CPP was calculated as the average cost of each regimen divided by eVPR.

RESULTS

Higher eVPR in the adult population was achieved with HepB-CpG (68.0%) versus HepB-Alum (41.6%), reflecting the combination of higher SPR and vaccine regimen completion. The CPP for HepB-CpG ($331.31) was $45.67 (95% CI: $36.66, $55.19) less than HepB-Alum ($377.09). Greater savings were observed among persons with diabetes, with CPP $149.60 (95% CI: $80.29, $195.63) lower with HepB-CpG ($367.57) than HepB-Alum ($517.37).

CONCLUSIONS

Metrics estimating vaccine real-world effectiveness and value may guide informed decisions in vaccine selection. For example, using eVPR and CPP, HepB-CpG represents a more effective, value-advantaged approach than HepB-Alum toward reducing HBV infection.

Preventing hepatitis B virus infection among healthcare professionals: potential impact of a 2-dose versus 3-dose vaccine

The exposure risk to the highly infectious hepatitis B virus (HBV) is an established and recognizable hazard to healthcare professionals (HCPs). In the United States, implementing preemptive vaccination programs and safety procedures resulted in drastic reductions in HBV infections among HCPs; however, many HCPs remain unprotected and risk of exposure persists, especially among those first entering a healthcare system and undergoing professional training. First-generation HBV vaccines require completion of a 3-dose schedule over a 6-month interval for maximum immunogenicity. By comparison, HepB-CpG (HEPLISAV-B®) is a 2-dose HBV vaccine licensed in the United States in 2017, inducing rapid seroprotection over a 1-month interval and may represent a more effective strategy for combating HBV infection in US healthcare systems. In this modeling study, the health and economic impact of implementing an HBV vaccination strategy with HepB-CpG versus the 3-dose HBV vaccine (Engerix-B®) was evaluated among HCPs newly entering a healthcare system. The model used effective seroprotection rate, a real-world metric accounting for HCP vaccine compliance and seroprotection rates for different dosing regimens and considered current pricing for postexposure prophylaxis treatment. Compared with the 3-dose vaccine, HepB-CpG was anticipated to provide faster, increased protection against HBV infection among newly entered HCPs. In protecting a greater percentage of HCPs, HepB-CpG was also projected to substantially reduce the risk of HBV exposure. Accordingly, an economic analysis showed HepB-CpG vaccination would reduce costs of postexposure prophylaxis treatment compared with the 3-dose vaccine. Overall, HepB-CpG represents an effective therapeutic strategy against HBV infection for US healthcare systems.

Anti-Viral Pattern Recognition Receptors as Therapeutic Targets

Pattern recognition receptors (PRRs) play a central role in the inflammation that ensues following microbial infection by their recognition of molecular patterns present in invading microorganisms but also following tissue damage by recognising molecules released during disease states. Such receptors are expressed in a variety of cells and in various compartments of these cells. PRR binding of molecular patterns results in an intracellular signalling cascade and the eventual activation of transcription factors and the release of cytokines, chemokines, and vasoactive molecules. PRRs and their accessory molecules are subject to tight regulation in these cells so as to not overreact or react in unnecessary circumstances. They are also key to reacting to infection and in stimulating the immune system when needed. Therefore, targeting PRRs offers a potential therapeutic approach for chronic inflammatory disease, infections and as vaccine adjuvants. In this review, the current knowledge on anti-viral PRRs and their signalling pathways is reviewed. Finally, compounds that target PRRs and that have been tested in clinical trials for chronic infections and as adjuvants in vaccine trials are discussed.

Update on the management and treatment of viral hepatitis

This review aims to summarize the current evidence on the treatment of viral hepatitis, focusing on its clinical management. Also, future treatment options and areas of potential research interest are detailed. PubMed and Scopus databases were searched for primary studies published within the last ten years. Keywords included hepatitis A virus, hepatitis B virus (HBV), hepatitis C virus, hepatitis D virus (HDV), hepatitis E virus, and treatment. Outcomes reported in the studies were summarized, tabulated, and synthesized. Significant advances in viral hepatitis treatment were accomplished, such as the advent of curative therapies for hepatitis C and the development and improvement of hepatitis A, hepatitis B, and hepatitis E vaccination. Drugs that cure hepatitis B, going beyond viral suppression, are so far unavailable; however, targeted antiviral drugs against HBV (immunomodulatory therapies and gene silencing technologies) are promising approaches to eradicating the virus. Ultimately, high vaccination coverage and large-scale test-and-treat programmes with high screening rates may eliminate viral hepatitis and mitigate their burden on health systems. The development of curative hepatitis C treatment renewed the enthusiasm for curing hepatitis B, albeit further investigation is required. Novel therapeutic options targeting HDV life cycle are currently under clinical investigation.

Two-Dose Hepatitis B Vaccine (Heplisav-B) Results in Better Seroconversion Than Three-Dose Vaccine (Engerix-B) in Chronic Liver Disease

BACKGROUND

The efficacy of the two-dose hepatitis B virus (HBV) vaccine (Heplisav-B^®) in patients with chronic liver disease (CLD) is unknown.

AIMS

To compare the immunogenicity achieved with Heplisav-B and the conventional three-dose vaccine (Engerix-B^®) in patients with CLD, and to identify factors that predict seroconversion.

METHODS

We retrospectively identified all adults who completed Heplisav-B or Engerix-B regimens from August 1, 2015, to January 31, 2019. Post-vaccination immunity was assessed by quantitative HBV surface antibody (HBsAb) measurement.

RESULTS

We identified 166 patients (106 Engerix-B and 60 Heplisav-B) with chronic liver disease (mean age 59.0 ± 11.3 years, 52% male, 34% cirrhosis, mean MELD score of those with cirrhosis 10.1 ± 5.4) who had completed the vaccinations and had data available on post-vaccination HBsAb levels at least 2 months after completion of the vaccine regimen. Seroprotective HBsAb levels (> 10 mIU/ml) were achieved in 63% with Heplisav-B and in 45% with Engerix-B (p = 0.03). Univariable analysis showed that age (p = 0.01), insurance (p = 0.02), renal failure (p = 0.02), COPD (p = 0.05), and cirrhosis (p < 0.01) had a significant effect on achieving immunogenicity. On multivariable analysis, patients with cirrhosis (adjusted odds ratio [aOR]: 0.27, 95% CI 0.13-0.55), COPD (aOR: 0.06, 95% CI 0.01-0.56), or renal failure (aOR 0.36, 95% CI 0.14-0.93) had a lower likelihood of achieving immunity, and patients who received Heplisav-B^® had a 2.7-fold greater likelihood of achieving immunity than those who received Engerix-B^® (aOR: 2.74, 95% CI 1.31-5.71).

CONCLUSION

The two-dose recombinant hepatitis B vaccine resulted in better seroconversion than the three-dose vaccine. Cirrhosis, COPD, and renal failure were associated with a lower likelihood of achieving immunogenicity.

Safety of vaccines used for routine immunization in the United States: An updated systematic review and meta-analysis

BACKGROUND

Understanding the safety of vaccines is critical to inform decisions about vaccination. Our objective was to conduct a systematic review of the safety of vaccines recommended for children, adults, and pregnant women in the United States.

METHODS

We searched the literature in November 2020 to update a 2014 Agency for Healthcare Research and Quality review by integrating newly available data. Studies of vaccines that used a comparator and reported the presence or absence of key adverse events were eligible. Adhering to Evidence-based Practice Center methodology, we assessed the strength of evidence (SoE) for all evidence statements. The systematic review is registered in PROSPERO (CRD42020180089).

RESULTS

Of 56,603 reviewed citations, 338 studies reported in 518 publications met inclusion criteria. For children, SoE was high for no increased risk of autism following measles, mumps, and rubella (MMR) vaccine. SoE was high for increased risk of febrile seizures with MMR. There was no evidence of increased risk of  intussusception with rotavirus vaccine at the latest follow-up (moderate SoE), nor of diabetes (high SoE). There was no evidence of increased risk or insufficient evidence for key adverse events for newer vaccines such as 9-valent human papillomavirus and meningococcal B vaccines. For adults, there was no evidence of increased risk (varied SoE) or insufficient evidence for key adverse events for the new adjuvanted inactivated influenza vaccine and recombinant adjuvanted zoster vaccine. We found no evidence of increased risk (varied SoE) for key adverse events among pregnant women following tetanus, diphtheria, and acellular pertussis vaccine, including stillbirth (moderate SoE).

CONCLUSIONS

Across a large body of research we found few associations of vaccines and serious key adverse events; however, rare events are challenging to study. Any adverse events should be weighed against the protective benefits that vaccines provide.

Comparative cost-effectiveness of a 2-dose versus 3-dose vaccine for hepatitis B prevention in selected adult populations

The hepatitis B virus is highly infectious and can cause incurable liver disease, leading to high morbidity rates, increased healthcare utilization, and high mortality. Multiple preventative hepatitis B vaccine options have been available for decades, but adherence to the traditional 6-month vaccine schedule for the approved 3-dose series remains low in adult populations at risk of hepatitis B exposure. A 2-dose hepatitis B vaccine (HEPLISAV-B) approved by the US Food and Drug Administration in 2017 induces rapid seroprotection within 1 month and has a safety profile comparable to a commonly used 3-dose vaccine. In a previous cost-effectiveness study, HEPLISAV-B had a favorable cost-effectiveness profile for multiple at-risk populations. The goal of the current analysis was to update and extend previous findings by evaluating cost-effectiveness of HEPLISAV-B compared with a 3-dose vaccine (Engerix-B) in selected adult populations, including patients with diabetes, chronic liver or kidney disease, end-stage renal disease, healthcare personnel, travelers to countries with endemic hepatitis B, and a public health population. Cost-effectiveness was measured as incremental cost-effectiveness ratios using a health economics Markov model that accounts for adherence rates, seroprotection rates, healthcare costs, and current pricing considerations. Patients progressed between a series of health states, and the difference in lifetime spending and survival for individuals receiving either HEPLISAV-B or Engerix-B was estimated from the perspective of a US managed care payer, HEPLISAV-B had favorable cost-effectiveness profiles for patients with diabetes, healthcare personnel, travelers, and patients with chronic liver disease and dominant incremental cost-effectiveness ratios for patients with chronic kidney disease and end-stage renal disease. A probabilistic sensitivity analysis supported the robustness of the cost-effectiveness profiles, and an additional analysis indicated that HEPLISAV-B was cost-effective in the general adult population. Overall, HEPLISAV-B was cost-effective in multiple adult populations recommended for HBV vaccination in the United States.

Immunogenicity and safety of a tri-antigenic versus a mono-antigenic hepatitis B vaccine in adults (PROTECT): a randomised, double-blind, phase 3 trial

BACKGROUND

The seroprotection rate (SPR) of hepatitis B vaccination in adults is suboptimal. The aim of this study was to compare the SPR of a tri-antigenic hepatitis B vaccine (TAV), with a mono-antigenic vaccine (MAV) in adults of all ages.

METHODS

This was a multicentre, double-blind, phase 3, randomised controlled trial (PROTECT) comparing the immunogenicity and safety of TAV with MAV in 28 community and hospital sites in the USA, Finland, Canada, and Belgium. Adults (aged ≥18 years) seronegative for hepatitis B virus (HBV), including those with well-controlled common chronic conditions, were randomly assigned (1:1) and stratified by study centre and age according to a web-based permuted blocked randomisation. Participants received either TAV or MAV which were administered as an intramuscular dose (1 mL) of TAV (10 μg; Sci-B-Vac, VBI Vaccines [SciVac, Rehovot, Israel]) or MAV (20 μg; Engerix-B [GlaxoSmithKline Biologicals, Rixensart, Belgium]) on days 0, 28, and 168 with six study visits and 24 weeks of follow-up after the third vaccination. Participants, investigators, and those assessing outcomes were masked to group assignment. The co-primary outcomes were to show non-inferiority of the SPRs 4 weeks after the third vaccination with TAV versus MAV in adults aged 18 years and older, as well as superiority in adults aged 45 years and older. SPR was defined as the percentage of participants attaining anti-HBs titres of 10 mIU/mL or higher. Non-inferiority of TAV to MAV was concluded if the lower limit of the 95% CI for the between-group difference was greater than -5%. Non-inferiority was assessed in the per-protocol set of participants (aged ≥18 years) and superiority was assessed in all participants (aged ≥45 years) who received at least one vaccination and had at least one evaluable immunogenicity sample after baseline (full analysis set). Safety analyses were a secondary outcome and included all participants who received at least one injection. This trial is registered at Clinicaltrials.gov (NCT03393754) and EudraCT (2017-001819-36) and is closed to new participants.

FINDINGS

Between Dec 13, 2017, and April 8, 2019, 1607 participants (796 allocated to TAV and 811 allocated to MAV) were randomly assigned and distributed across age cohorts of 18-44 years (299 of 1607; 18·6%), 45-64 years (716 of 1607; 44·6%), and 65 years and older (592 of 1607; 36·8%). In participants aged 18 years and older, SPR was 91·4% (656 of 718) in the TAV group versus 76·5% (553 of 723) in the MAV group (difference 14·9%, 95% CI 11·2-18·6), showing non-inferiority in the per-protocol set. In participants aged 45 years and older, SPR was 89·4% (559 of 625) in the TAV group versus 73·1% (458 of 627) in the MAV group (difference 16·4%, 95% CI 12·2-20·7), showing superiority in the full analysis set. TAV was associated with higher rates of mild or moderate injection site pain (63·2% [503 of 796] in TAV vs 36·3% [294 of 811] in MAV), tenderness (60·8% [484 of 796] in TAV vs 34·8% [282 of 811] in MAV), and myalgia (34·7% [276 of 796] vs 24·3% [197 of 811] in MAV). Otherwise, the safety profile of TAV was similar to that of MAV.

INTERPRETATION

The safety and efficacy of TAV shows its usefulness for the prevention of HBV infection in adults, including those with stable and controlled chronic conditions.

FUNDING

VBI Vaccines.

Vaccines for immunoprevention of cancer

The immunoprevention of cancer and cancer recurrence is an important area of concern for the scientific community and society as a whole. Researchers have been working for decades to develop vaccines with the potential to alleviate these health care and economic burdens. So far, vaccines have made more progress in preventing cancer than in eliminating already established cancer. In particular, vaccines targeting oncogenic viruses, such as the human papillomavirus and the hepatitis B virus, are exceptional examples of successful prevention of virus-associated cancers, such as cervical cancer and hepatocellular carcinoma. Cancer-preventive vaccines targeting nonviral antigens, such as tumor-associated antigens and neoantigens, are also being extensively tested. Here, we review the currently approved preventive cancer vaccines; discuss the challenges in this field by covering ongoing preclinical and clinical human trials in various cancers; and address various issues related to maximizing cancer vaccine benefit.

CpG-Adjuvanted Hepatitis B Vaccine (HEPLISAV-B®) Update

Introduction: HEPLISAV-B is a hepatitis B vaccine composed of rHBsAg mixed with a synthetic oligonucleotide containing CpG motifs that stimulate innate immunity through TLR9. This vaccine was recently approved by FDA in view of its superior efficacy.Areas covered: Published literature on HEPLISAV-B was critically reviewed. Four randomized controlled trials among 7,056 subjects receiving 2 doses of HEPLISAV-B and 3,214 subjects receiving 3 doses of Engerix-B showed superior seroprotection rate (SPR) (anti-HBs ≥10 mIU/mL) of 90-100%, compared with 71-90% in those receiving Engerix-B. Furthermore, the seroprotection rate was also significantly higher in HEPLISAV-B compared with Engerix-B recipients in persons with traditionally poor vaccine responses such as older adults, diabetics, and those with chronic kidney disease. The safety profiles among 9,871 subjects were similar between HEPLISAV-B and Engerix-B .Expert opinion: HEPLISAV-B, a CpG adjuvant mixed with HBsAg, is more efficacious and produced earlier seroprotection compared to existing vaccines, with a favorable safety profile. The shorter, two-dose regimen, earlier seroprotection, higher adherence, and a higher seroprotection rate, especially in populations with traditionally poor vaccine response, makes this an important therapeutic option in hepatitis B vaccination.

Emerging concepts in the science of vaccine adjuvants

Adjuvants are vaccine components that enhance the magnitude, breadth and durability of the immune response. Following its introduction in the 1920s, alum remained the only adjuvant licensed for human use for the next 70 years. Since the 1990s, a further five adjuvants have been included in licensed vaccines, but the molecular mechanisms by which these adjuvants work remain only partially understood. However, a revolution in our understanding of the activation of the innate immune system through pattern recognition receptors (PRRs) is improving the mechanistic understanding of adjuvants, and recent conceptual advances highlight the notion that tissue damage, different forms of cell death, and metabolic and nutrient sensors can all modulate the innate immune system to activate adaptive immunity. Furthermore, recent advances in the use of systems biology to probe the molecular networks driving immune response to vaccines ('systems vaccinology') are revealing mechanistic insights and providing a new paradigm for the vaccine discovery and development process. Here, we review the 'known knowns' and 'known unknowns' of adjuvants, discuss these emerging concepts and highlight how our expanding knowledge about innate immunity and systems vaccinology are revitalizing the science and development of novel adjuvants for use in vaccines against COVID-19 and future pandemics.

Brief Report: Heplisav-B Seroprotection in People With HIV: A Single-Center Experience

BACKGROUND

Heplisav-B, a hepatitis B virus (HBV) vaccine with an immunostimulatory adjuvant, was FDA approved in 2017 for adults ≥18 years. In randomized controlled trials, Heplisav-B demonstrated seroprotection rates (SPR) of 90%-95% versus 65%-80% for Engerix-B. No studies have included people with HIV (PWH), and the SPR and its predictors in this population are unknown.

SETTING

Quaternary care center HIV clinic.

METHODS

This retrospective cohort study evaluated PWH aged ≥18 years without current HBV seroprotection (anti-HBV surface antibody level [anti-HBs] <10 mIU/mL) who were administered Heplisav-B. Patients without post-immunization titers were excluded. The primary outcome was the SPR, the proportion of participants with HBV seroprotection at any point after the first vaccination.

RESULTS

Among 64 PWH included, median time to anti-HBs measurement after vaccination was 13 weeks. The median age was 58 years, 81% were men, and 95% had a viral load <200. The SPR was 81% in the entire cohort (and 86% in those without significant non-HIV immunosuppression), 79% in those with no prior HBV vaccination and no anti-HBc positivity, and 84% in those with prior vaccine nonresponse. Lower current and nadir CD4+ counts were associated with progressively lower seroprotection.

CONCLUSION

In the first single-center retrospective study of Heplisav-B in PWH, the SPR compared favorably with the SPR seen among PWH from prior HBV vaccines across key subgroups. Given these findings, Heplisav-B should be considered for expanded use for HBV vaccination in PWH. Further research on the effectiveness of a repeat vaccination series or higher dosing in nonresponders is needed.

Immunogenicity of Varicella-Zoster Virus Glycoprotein E Formulated with Lipid Nanoparticles and Nucleic Immunostimulators in Mice

Theoretically, the subunit herpes zoster vaccine Shingrix^TM could be used as a varicella vaccine that avoids the risk of developing shingles from vaccination, but bedside mixing strategies and the limited supply of the adjuvant component QS21 have made its application economically impracticable. With lipid nanoparticles (LNPs) that were approved by the FDA as vectors for severe acute respiratory syndrome coronavirus 2 vaccines, we designed a series of vaccines efficiently encapsulated with varicella-zoster virus glycoprotein E (VZV-gE) and nucleic acids including polyinosinic-polycytidylic acid (Poly I:C) and the natural phosphodiester CpG oligodeoxynucleotide (CpG ODN), which was approved by the FDA as an immunostimulator in a hepatitis B vaccine. Preclinical trial in mice showed that these LNP vaccines could induce VZV-gE IgG titers more than 16 times those induced by an alum adjuvant, and immunized serum could block in vitro infection completely at a dilution of 1:80, which indicated potential as a varicella vaccine. The magnitude of the cell-mediated immunity induced was generally more than 10 times that induced by the alum adjuvant, indicating potential as a zoster vaccine. These results showed that immunostimulatory nucleic acids together with LNPs have promise as safe and economical varicella and zoster vaccine candidates.

CpG Oligonucleotides as Vaccine Adjuvants

CpG Oligonucleotides (ODN) are immunomodulatory synthetic oligonucleotides specifically designed to stimulate Toll-like receptor 9. TLR9 is expressed on human plasmacytoid dendritic cells and B cells and triggers an innate immune response characterized by the production of Th1 and pro-inflammatory cytokines. This chapter reviews recent progress in understanding the mechanism of action of CpG ODN and provides an overview of human clinical trial results using CpG ODN to improve vaccines for the prevention/treatment of cancer, allergy, and infectious disease.

Cost-Effectiveness of an Adjuvanted Hepatitis B Vaccine (HEPLISAV-B) in Patients With Inflammatory Bowel Disease

Background

Compare the cost-effectiveness of 2 recombinant hepatitis B virus (HBV) vaccines in patients with inflammatory bowel disease (IBD).

Methods

Markov models were developed for 2 IBD cohorts: (1) 40-year-old patients prior to starting IBD treatment and (2) 40-year-old patients already receiving therapy. Cohort A received full vaccination series, cohort B had primary vaccine failure and received a vaccine booster. Two vaccines were compared: adjuvanted HEPLISAV-B and nonadjuvanted Engerix-B. Clinical probabilities of acute hepatitis, chronic hepatitis, cirrhosis, fulminant hepatic failure and death, treatment costs, and effectiveness estimates were obtained from published literature. A lifetime analysis and a US payer perspective were used. Probabilistic sensitivity analyses were performed for different hypothetical scenarios.

Results

Analysis of cohort A showed moderate cost-effectiveness of HEPLISAV-B ($88,114 per quality-adjusted life year). Analysis of cohort B showed increased cost-effectiveness ($35,563 per quality-adjusted life year). Changing Engerix-B to HEPLISAV-B in a hypothetical group of 100,000 patients prevented 6 and 30 cases of acute hepatitis; and 4 and 5 cases of chronic hepatitis annually for cohorts A and B, respectively. It also prevented 1 and 2 cases of cirrhosis, and 1 and 2 deaths over 20 years for each cohort. Cost-effectiveness was determined by vaccination costs, patient age, and progression rate from chronic hepatitis to cirrhosis.

Conclusions

HEPLISAV-B is cost-effective over Engerix-B in patients receiving immunosuppressive therapy for IBD. Benefits increase with population aging and lower costs of vaccines. We advocate measuring levels of HBV antibodies in patients with IBD and favor adjuvanted vaccines when vaccination is needed.

Clinical Applications of Single-Stranded Oligonucleotides: Current Landscape of Approved and In-Development Therapeutics

Single-stranded oligonucleotides have been explored as a therapeutic modality for more than 20 years. Only during the last 5 years have single-stranded oligonucleotides become a modality of choice in the fields of precision medicine and targeted therapeutics. Recently, there have been a number of development efforts involving this modality that have led to treatments for genetic diseases that were once untreatable. This review highlights key applications of single-stranded oligonucleotides that function in a sequence-dependent manner when applied to modulate precursor (pre-)mRNA splicing, gene expression, and immune pathways. These applications have been used to address diseases that range from neurological to muscular to metabolic, as well as to develop vaccines. The wide range of applications denotes the versatility of single-stranded oligonucleotides as a robust therapeutic platform. The focus of this review is centered on approved single-stranded oligonucleotide therapies and the evolution of oligonucleotide therapeutics into novel applications currently in clinical development.

Assessing the cost-utility of preferentially administering Heplisav-B vaccine to certain populations

Vaccination is the primary strategy to prevent hepatitis B virus (HBV) infection in the United States. Prior to 2017, most standard hepatitis B vaccine schedules required 3 doses over 6 months. Heplisav-B, approved in 2017, is administered in 2 doses over a 1 month time period but has a higher per-dose cost ($115.75 per dose compared to $57.25 per Engerix-B dose, costs as of June 1, 2019). We aimed to assess the cost-utility of providing the two-dose Heplisav-B vaccine compared to a three-dose Engerix-B vaccine among adult populations currently recommended for vaccination against hepatitis B. We used a decision-tree model with microsimulation and a Markov disease progression process to assess the cost-utility separately for the following populations: adults with diabetes, obesity, chronic kidney disease, HIV; non-responders to previous hepatitis B vaccination; older adults; and persons who inject drugs (PWID). We modeled epidemiologic outcomes (incident HBV infections, sequelae and related deaths), costs (2019 USD) and benefits (quality-adjusted life years, QALYs) and compared them across strategies. Sensitivity analyses assessed the cost-utility at varying estimates of Heplisav-B efficacy. In the base case scenario for each population, vaccination with Heplisav-B resulted in fewer HBV infections (37.5-59.8% averted), sequelae, and HBV-related deaths (36.3-71.4% averted). Heplisav-B resulted in decreased costs and increased benefits compared to Engerix-B for all populations except non-responders. Incremental costs from the baseline strategy ranged from $4746.78 saved (PWID) to $14.15 added cost (non-responders). Incremental benefits per person ranged from 0.00005 QALYs (older adults) to 0.7 QALYs (PWID). For persons with HIV and PWID, Heplisav-B resulted in lower costs and increased benefits in all scenarios in which Heplisav-B series efficacy was at least 80%. Vaccination using Heplisav-B is a cost-saving strategy compared to Engerix-B for adults with diabetes, chronic kidney disease, obesity, and HIV; older adults; and PWID.

Association of Number of Doses With Hepatitis B Vaccine Series Completion in US Adults

IMPORTANCE

Receipt of hepatitis B virus vaccine is important to prevent infection. However, adherence to the hepatitis B vaccine series among adults at risk of infection has been low.

OBJECTIVE

To assess whether recipients of a 2-dose hepatitis B vaccine with cytosine phosphoguanine adjuvant (HepB-CpG vaccine; Heplisav-B) are more likely to complete their series compared with recipients of a 3-dose vaccine with alum adjuvant (comparator vaccine; Engerix-B [HepB-alum]).

DESIGN, SETTING, AND PARTICIPANTS

This nested cohort study was conducted from August 7 to December 31, 2018, at Kaiser Permanente Southern California, an integrated health care system with a diverse population of approximately 4.6 million members. Adults not receiving dialysis who received a first dose of a hepatitis B vaccine series in family practice or internal medicine departments of 15 Kaiser Permanente Southern California medical centers were followed up through electronic health records for up to 1 year after receipt of the first dose. Data were analyzed from March 16 to September 23, 2020.

EXPOSURES

Receipt of a first dose of the HepB-CpG vaccine (2-dose vaccine) vs receipt of a first dose of the HepB-alum vaccine (3-dose vaccine).

MAIN OUTCOMES AND MEASURES

Series completion within the recommended vaccine schedule plus 3 months (primary outcome) and series completion within 1 year after receipt of the first dose (secondary outcome).

RESULTS

Of 4727 individuals who initiated the HepB-CpG vaccine series and 6161 individuals who initiated the HepB-alum vaccine series included in the study, 2876 (60.8%) and 3789 (61.5%), respectively, were ages 40 to 59 years, 2415 (51.1%) and 3113 (50.5%) were male, and 2364 (50.0%) and 2881 (46.8%) were Hispanic. The vaccine series was completed within the recommended schedule plus 3 months for 2111 (44.7%) individuals who initiated the HepB-CpG vaccine series and 1607 (26.1%) individuals who initiated the HepB-alum vaccine series, and within 1 year for 2858 (60.5%) and 1989 (32.3%) individuals, respectively. The individuals who initiated the HepB-CpG vaccine series were significantly more likely to complete the series (adjusted relative risk, 1.77; 95% CI, 1.68-1.87). Results were consistent across clinical and demographic strata.

CONCLUSIONS AND RELEVANCE

In this study, use of the HepB-CpG vaccine was associated with hepatitis B vaccine series completion, but tailored strategies to increase completion of hepatitis B vaccine series are warranted.

Efficacy and Safety of a 3-Antigen (Pre-S1/Pre-S2/S) Hepatitis B Vaccine: Results of a Phase 3 randomized clinical trial in the Russian Federation

Background

This study compares the immunogenicity and safety of a 3-antigen (S/pre-S1/pre-S2) hepatitis B (HepB) vaccine (3AV), to a single antigen vaccine (1AV) in adults to support the registration of 3AV in Russia.

Methods

We conducted a randomized, double-blind, comparative study of 3-dose regimens of 3AV (10 μg) and 1AV (20 µg) in adults aged 18–45 years. We evaluated immunogenicity based on hepatitis B surface (HBs) antibody titers at days 1, 28, 90, 180, and 210, adverse and serious adverse events (SAEs) to study day 210. The primary outcome was based on the difference in rates of seroconversion at day 210 (lower bound 95% confidence interval [CI]: > − 4%). Secondary outcomes were seroprotection rates (SPR), defined as anti-HBs ≥10 mIU/mL and anti-HBs geometric mean concentration (GMC).

Results

Rate of seroconversion in 3AV (100%) was noninferior to 1AV (97.9%) at study day 210 (difference: 2.1%, 95% CI: −2.0, 6.3%]) but significantly higher at study day 28. SPR at study day 210 was >97% in both arms. Anti-HBs titers were significantly higher at study days 90 (P = .001) and 180 (P = .0001) with 3AV. Sex, age, and body mass index (BMI) had no impact on anti-HBs titers. The rates of local reactions related to vaccination were similar between vaccine arms (3AV vs 1AV) after the first (30% vs 18.8%, P = .15), second (20.0% vs 14.6%, P = .33), and third vaccination (14.9% vs 23.4%, P = .22). No SAEs were reported.

Conclusions

3AV was noninferior to 1AV. 3AV induced high SPR, and there were no safety concerns.

Clinical Trials Registration. NCT04209400.

Safety of Recombinant Zoster Vaccine in Patients with Inflammatory Bowel Disease

BACKGROUND

Patients with inflammatory bowel disease (IBD) are at increased risk of developing herpes zoster. In October 2017, the FDA approved a two-dose adjuvanted, recombinant herpes zoster vaccine (RZV). There is a theoretical concern that vaccine adjuvants may cause flares in patients with immune-mediated diseases. We aimed to assess the rates of IBD flare and adverse reactions after administration of RZV in a cohort of patients with IBD.

METHODS

We conducted a prospective observational study of patients with IBD who received RZV between February 2018 and July 2019 at a tertiary IBD referral center. IBD activity scores were collected from patients during office visit or phone call after vaccination. The primary outcome was rate of IBD flare, defined as an increase in IBD activity, resulting in escalation of medical therapy, following vaccination. The secondary outcomes were rates of local and systemic adverse reactions after vaccination.

RESULTS

We identified 67 patients (28 with ulcerative colitis and 39 with Crohn's disease) who received at least one dose of RZV. The two-dose vaccine series was completed by 55 patients (82%). Median duration of follow-up after vaccination was 207 days. One case of IBD flare was identified. No cases of herpes zoster were identified. Local and systemic adverse reactions were reported in 74.6% and 56.7% of patients, respectively.

CONCLUSIONS

In this cohort of 67 patients, a low rate of IBD flare (1.5%) was observed after RZV administration. Rates of local and systemic adverse reactions were comparable to those seen in the RZV clinical trials.

Heplisav-B: A Hepatitis B Vaccine With a Novel Adjuvant

OBJECTIVE

To review the immunogenicity and safety of a hepatitis B vaccine containing the cytosine phosphoguanosine (CpG) 1018 adjuvant (HepB-CpG).

DATA SOURCES

Literature searches were performed using PubMed and Scopus with the search terms hepatitis B vaccine, HepB-CpG, CpG 1018, 1018-ISS, HBsAg-1018, HBV-ISS, and Heplisav. Other sources included the Centers for Disease Control, the Food and Drug Administration, the Advisory Committee on Immunization Practices (ACIP), and prescribing information.

STUDY SELECTION AND DATA EXTRACTION

Search limits included randomized controlled trial in humans and published in English from January 2003 to August 2020. Studies using the final formulation and dosing schedule were reviewed.

DATA SYNTHESIS

Studies demonstrated that 2 doses of HepB-CpG induced significantly higher seroprotective responses with a faster onset in adults, including those in hyporesponsive populations, compared with 3 doses of alum-adjuvanted Engerix-B. Although the safety profile was comparable to that of Engerix-B, one study observed higher rates of acute myocardial infarction, herpes zoster, and death with HepB-CpG.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

ACIP recommends use of HepB-CpG as an option to prevent hepatitis B virus infection in adults ≥18 years old. Higher immune responses after 2 doses make it a promising option, especially in those with risk factors for hyporesponsiveness or at risk for poor adherence to vaccine series completion. Additional data are needed regarding the vaccine's safety in the general population and the persistence of its antibody response.

CONCLUSION

HepB-CpG has been shown to be as immunogenic as Engerix-B; however, long-term safety and persistence of immune memory has yet to be established.

Hepatitis B vaccine development and implementation

Vaccination against hepatitis B is the most effective strategy to control HBV infection. The first licensed hepatitis B vaccine was developed by the purification of hepatitis B surface antigen (HBsAg) from plasma of asymptomatic HBsAg carriers. Then, the recombinant DNA technology enabled the development of recombinant hepatitis B vaccine. A series of three doses vaccine can elicit long-term protection more than 30 y. Concurrent use of hepatitis B immunoglobulin and hepatitis B vaccine has substantially reduced the mother-to-child transmission of HBV, nearly zero infection in children of carrier mother with negative hepatitis B e antigen (HBeAg) and 5-10% infection in children of HBeAg-positive mothers. By the end of 2018, 189 countries adopted universal hepatitis B vaccination program, which has dramatically reduced the global prevalence of HBsAg in children <5 y of age, from 4.7% in the prevaccine era to 1.3% in 2015. However, the implementation of universal hepatitis B vaccination in some regions is suboptimal and timely birth dose vaccine is not routinely administered in more than half of newborn infants. Optimal worldwide universal hepatitis B vaccination requires more efforts to overcome the social and economic challenges.

What's New in Vaccine Science

Today vaccines can provide immunity against and treatment of a growing number of diseases including noninfectious conditions. Vaccine science continues to evolve newer and safer ways to deliver prevention and treatment of infectious and noninfectious diseases. This includes new adjuvants to enhance immunogenicity; delivery systems to reduce pain and improve acceptability; a wider range of uses including preventing emerging infectious diseases, such as Zika virus and Ebola, treatment of chronic diseases, such as cancer, and autoimmune disorders; and repurposing of existing vaccines, such as bacillus Calmette-Guérin for novel therapies.