Recent developments in the understanding and use of anthrax vaccine adsorbed: achieving more with less

A historical analysis of vaccine mandates in the United States military and its application to the COVID-19 vaccine mandate

The Department of Defense has implemented a mandate that all military personnel be vaccinated against COVID-19. This article reviews the historical precedent of vaccine mandates for United States military personnel dating back to the formation of the continental army, as well as previous controversies about vaccine mandates such as the first influenza vaccine mandate and the Anthrax Vaccine Immunization Program. The historical review discusses precedent for the current COVID-19 vaccine mandate and the reception of these vaccine mandates by military personnel. The review then discusses how these historical lessons can inform the present COVID-19 vaccine mandate.

Epizootological and epidemiological situation of anthrax in Ukraine in the context of mandatory specific prevention in susceptible animals

The problem of zoonoses remains relevant in the context of reliable prevention of human disease and effective ways to achieve this result, in particular through the impact on susceptible animals by the efforts of veterinary medicine. Anthrax is an acute, particularly dangerous infectious disease of all species of farm, domestic and wild animals, as well as humans, which is caused by Bacillus anthracis microbes. The causative agent of anthrax belongs to the group of aerobic spore-forming bacteria and exists in two main forms: vegetative and spore. The vegetative form in the body of an infected animal can form a "capsule". In Ukraine, according to the provisions of the current "Instruction for the prevention and control of animal anthrax" (2000), the main method of preventing anthrax among animals is regular vaccination of animals susceptible to this disease. The authors conducted a retrospective analysis of the epizootic and epidemiological situation of anthrax in Ukraine for the period 1994–2021 and made a critical assessment of the performance of mandatory measures for specific prevention of susceptible animals. In order to find out the ecological and geographical features of the spread of anthrax, data on outbreaks of the disease in cattle, swine, small ruminants and humans on the territory of Ukraine were analyzed by regions for the time period under investigation. Over the past 28 years in Ukraine, animal anthrax was registered in in all areas except Zhytomyr region. In total, during the analyzed period, 177 affected points and 637 infected animals (cattle, small ruminants, pigs, horses, wild and fur-bearing animals, dogs) were registered (estimated at 3.59 animals per outbreak). Cattle were most often involved in the epizootic process, followed by pigs and small ruminants, while horses and other animal species were least infected. Ecological and geographical analysis showed that the largest number of affected points among animals during the analyzed period was found in Kyiv, Volyn, Kharkiv, Luhansk, Khmelnytskyi, Cherkasy, Odesa, and Vinnytsia regions. A small number of affected points during the analyzed period were found in Zakarpattia, Ternopil, Kherson, Autonomous Republic of Crimea, Poltava, Dnipropetrovsk and Ivano-Frankivsk regions. During the analyzed period, 68 people in 11 regions of Ukraine were infected with anthrax, 15 outbreaks were registered (4.46 people per outbreak). Most cases were reported in Donetsk, Kyiv and Odesa regions. The association between outbreaks of anthrax in animals and cases of anthrax among humans has been established, this dependency was 86.6% (the index of contiguity, which takes into account the number of years with simultaneous registration of animal and human cases, was 0.5). The authors thoroughly proved that it is vaccination among susceptible animals that will finally prevent the incidence of anthrax among people.

Biodefence research two decades on: worth the investment?

For the past 20 years, the notion of bioterror has been a source of considerable fear and panic worldwide. In response to the terror attacks of 2001 in the USA, extensive research funding was awarded to investigate bioterror-related pathogens. The global scientific legacy of this funding has extended into the present day, highlighted by the ongoing COVID-19 pandemic. Unsurprisingly, the surge in biodefence-related research and preparedness has been met with considerable apprehension and opposition. Here, we briefly outline the history of modern bioterror threats and biodefence research, describe the scientific legacy of biodefence research by highlighting advances pertaining to specific bacterial and viral pathogens, and summarise the future of biodefence research and its relevance today. We sought to address the sizeable question: have the past 20 years of investment into biodefence research and preparedness been worth it? The legacy of modern biodefence funding includes advancements in biosecurity, biosurveillence, diagnostics, medical countermeasures, and vaccines. In summary, we feel that these advances justify the substantial biodefence funding trend of the past two decades and set a precedent for future funding.

Repeat Dose Toxicity Study of the AV7909 Anthrax Vaccine Candidate in Juvenile Rats

AV7909 is a next-generation anthrax vaccine candidate indicated for post-exposure prophylaxis of exposure to Bacillus anthracis. AV7909 consists of the Anthrax Vaccine Adsorbed (AVA) bulk drug substance and the immunostimulatory Toll-like receptor 9 agonist oligodeoxynucleotide adjuvant, CPG 7909. Safety testing for pediatric population is warranted to support the potential emergency use of AV7909 in children. This study was conducted to investigate the local tolerance and potential systemic toxicity and their reversibility in juvenile rats by repeat intramuscular injections of the AV7909 vaccine candidate. Animals were dosed on postnatal day (PND) 21 (at weaning), PND 28, and PND 35, with the test article (AV7909), the adjuvant alone (Alhydrogel + CPG 7909), or sterile water for injection. Core group animals were necropsied on PND 37 and recovery group on PND 49. Study end points included survival, clinical observations, injection site observations, body weights, clinical pathology (hematology, coagulation, and clinical chemistry), pro-inflammatory biomarker analysis (alpha-2 macroglobulin [A2M] and alpha-1 acid glycoprotein [AGP]), and anatomic pathology. Immune response to vaccination was measured using the high-throughput anthrax lethal toxin neutralization assay (htpTNA). The AV7909 vaccine candidate produced no apparent systemic or local toxicity. The AGP and A2M levels were elevated in both the adjuvant-alone and AV7909 groups at the end of treatment but were comparable to control levels by the end of the recovery period. All animals in the AV7909 group demonstrated a robust neutralizing antibody response. The results indicate that AV7909 has a favorable safety profile in juvenile rats.

Current Status and Trends in Prophylaxis and Management of Anthrax Disease

Bacillus anthracis has been identified as a potential military and bioterror agent as it is relatively simple to produce, with spores that are highly resilient to degradation in the environment and easily dispersed. These characteristics are important in describing how anthrax could be used as a weapon, but they are also important in understanding and determining appropriate prevention and treatment of anthrax disease. Today, anthrax disease is primarily enzootic and found mostly in the developing world, where it is still associated with considerable mortality and morbidity in humans and livestock. This review article describes the spectrum of disease caused by anthrax and the various prevention and treatment options. Specifically we discuss the following; (1) clinical manifestations of anthrax disease (cutaneous, gastrointestinal, inhalational and intravenous-associated); (2) immunology of the disease; (3) an overview of animal models used in research; (4) the current World Health Organization and U.S. Government guidelines for investigation, management, and prophylaxis; (5) unique regulatory approaches to licensure and approval of anthrax medical countermeasures; (6) the history of vaccination and pre-exposure prophylaxis; (7) post-exposure prophylaxis and disease management; (8) treatment of symptomatic disease through the use of antibiotics and hyperimmune or monoclonal antibody-based antitoxin therapies; and (9) the current landscape of next-generation product candidates under development.

Immunogenicity and safety of a novel recombinant protective antigen anthrax vaccine (GC1109), a randomized, single-blind, placebo controlled phase II clinical study

BACKGROUND

The demand on effective and safe anthrax vaccine is increasing as a part of the preparedness for possible bioterrorism in the future. We performed a randomized, single-blind, placebo controlled phase II clinical study to evaluate the immunogenicity and safety of a novel recombinant protective antigen (rPA) anthrax vaccine, GC1109, in healthy adult volunteers.

METHODS

Participants were randomized to experiment groups (0.3 mL, 0.5 mL, and 1.0 mL of GC1109) or placebo group (normal saline 0.5 mL) in 2:2:2:1 ratio. They received respective vaccines intramuscularly at 0, 4 and 8 weeks. Immunogenicity was evaluated by seroconversion rate and geometric mean titer (GMT) of lethal toxin neutralizing assay (TNA) and anti-PA IgG by ELISA. Safety was assessed by laboratory tests, and solicited and unsolicited adverse events on diary cards.

RESULTS

30, 29, 30 participants were randomized to 0.3, 0.5, and 1.0 mL of GC1109 groups, respectively, while 15 to placebo group. 92 participants received all three doses. In per-protocol analysis, TNA GMTs at week 12 were 296.5, 285.2, and 433.2 in the three groups, respectively. Seroconversion rates measured by ELISA were 100% at week 12 in the three groups. Local and systemic vaccine-related adverse events were frequent; however, most of them were mild, and no serious events were observed.

CONCLUSIONS

A new rPA anthrax vaccine GC1109 was immunogenic after three doses of intramuscular administration, and was well-tolerated.

Assessing the Importance of Domestic Vaccine Manufacturing Centers: An Overview of Immunization Programs, Vaccine Manufacture, and Distribution

Vaccines have significantly reduced the detrimental effects of numerous human infectious diseases worldwide, helped to reduce drastically child mortality rates and even achieved eradication of major pathogens, such as smallpox. These achievements have been possible due to a dedicated effort for vaccine research and development, as well as an effective transfer of these vaccines to public health care systems globally. Either public or private institutions have committed to developing and manufacturing vaccines for local or international population supply. However, current vaccine manufacturers worldwide might not be able to guarantee sufficient vaccine supplies for all nations when epidemics or pandemics events could take place. Currently, different countries produce their own vaccine supplies under Good Manufacturing Practices, which include the USA, Canada, China, India, some nations in Europe and South America, such as Germany, the Netherlands, Italy, France, Argentina, and Brazil, respectively. Here, we discuss some of the vaccine programs and manufacturing capacities, comparing the current models of vaccine management between industrialized and developing countries. Because local vaccine production undoubtedly provides significant benefits for the respective population, the manufacture capacity of these prophylactic products should be included in every country as a matter of national safety.