-
Vaccines Feb 2024Vaccines are essential tools to prevent infection and control transmission of infectious diseases that threaten public health. Most infectious agents enter their hosts... (Review)
Review
Vaccines are essential tools to prevent infection and control transmission of infectious diseases that threaten public health. Most infectious agents enter their hosts across mucosal surfaces, which make up key first lines of host defense against pathogens. Mucosal immune responses play critical roles in host immune defense to provide durable and better recall responses. Substantial attention has been focused on developing effective mucosal vaccines to elicit robust localized and systemic immune responses by administration via mucosal routes. Mucosal vaccines that elicit effective immune responses yield protection superior to parenterally delivered vaccines. Beyond their valuable immunogenicity, mucosal vaccines can be less expensive and easier to administer without a need for injection materials and more highly trained personnel. However, developing effective mucosal vaccines faces many challenges, and much effort has been directed at their development. In this article, we review the history of mucosal vaccine development and present an overview of mucosal compartment biology and the roles that mucosal immunity plays in defending against infection, knowledge that has helped inform mucosal vaccine development. We explore new progress in mucosal vaccine design and optimization and novel approaches created to improve the efficacy and safety of mucosal vaccines.
PubMed: 38400174
DOI: 10.3390/vaccines12020191 -
International Journal of Infectious... Jun 2024Tropical infectious diseases inflict an unacceptable burden of disease on humans living in developing countries. Although anti-pathogenic drugs have been widely used,... (Review)
Review
Tropical infectious diseases inflict an unacceptable burden of disease on humans living in developing countries. Although anti-pathogenic drugs have been widely used, they carry a constant threat of selecting for resistance. Vaccines offer a promising means by which to enhance the global control of tropical infectious diseases; however, these have been difficult to develop, mostly because of the complex nature of the pathogen lifecycles. Here, we present recently developed vaccine candidates for five tropical infectious diseases in the form of a catalog that have either entered clinical trials or have been licensed for use. We deliberate on recently licensed dengue vaccines, provide evidence why combination vaccination could have a synergistic impact on schistosomiasis, critically appraise the value of typhoid conjugate vaccines, and discuss the potential of vaccines in the efforts to eliminate vivax malaria and hookworms.
Topics: Humans; Dengue; Dengue Vaccines; Schistosomiasis; Communicable Diseases; Tropical Medicine; Vaccines; Typhoid Fever; Malaria, Vivax; Vaccine Development
PubMed: 38499058
DOI: 10.1016/j.ijid.2024.107014 -
Frontiers in Oncology 2023Cancer is a devastating disease with a high global mortality rate and is projected to increase further in the coming years. Current treatment options, such as... (Review)
Review
Cancer is a devastating disease with a high global mortality rate and is projected to increase further in the coming years. Current treatment options, such as chemotherapy and radiation therapy, have limitations including side effects, variable effectiveness, high costs, and limited availability. There is a growing need for alternative treatments that can target cancer cells specifically with fewer side effects. Phages, that infect bacteria but not eukaryotic cells, have emerged as promising cancer therapeutics due to their unique properties, including specificity and ease of genetic modification. Engineered phages can transform cancer treatment by targeting cancer cells while sparing healthy ones. Phages exhibit versatility as nanocarriers, capable of delivering therapeutic agents like gene therapy, immunotherapy, and vaccines. Phages are extensively used in vaccine development, with filamentous, tailed, and icosahedral phages explored for different antigen expression possibilities. Engineered filamentous phages bring benefits such as built in adjuvant properties, cost-effectiveness, versatility in multivalent formulations, feasibility of oral administration, and stability. Phage-based vaccines stimulate the innate immune system by engaging pattern recognition receptors on antigen-presenting cells, enhancing phage peptide antigen presentation to B-cells and T-cells. This review presents recent phage therapy advances and challenges in cancer therapy, exploring its versatile tools and vaccine potential.
PubMed: 38033486
DOI: 10.3389/fonc.2023.1290296 -
Vaccines Jun 2023Traditional vaccines use inactivated or weakened forms of pathogens which could have side effects and inadequate immune responses. To overcome these challenges, phage... (Review)
Review
Traditional vaccines use inactivated or weakened forms of pathogens which could have side effects and inadequate immune responses. To overcome these challenges, phage display has emerged as a valuable tool for identifying specific epitopes that could be used in vaccines. This review emphasizes the direct connection between epitope identification and vaccine development, filling a crucial gap in the field. This technique allows vaccines to be engineered to effectively stimulate the immune system by presenting carefully selected epitopes. Phage display involves screening libraries of random peptides or gene/genome fragments using serum samples from infected, convalescent, or vaccinated individuals. This method has been used to identify epitopes from various pathogens including SARS-CoV-2, Mycobacterium tuberculosis, hepatitis viruses, H5N1, HIV-1, Human T-lymphotropic virus 1, , , and . Bacteriophages offer advantages such as being immunogenic carriers, low production costs, and customization options, making them a promising alternative to traditional vaccines. The purpose of this study has been to highlight an approach that encompasses the entire process from epitope identification to vaccine production using a single technique, without requiring additional manipulation. Unlike conventional methods, phage display demonstrates exceptional efficiency and speed, which could provide significant advantages in critical scenarios such as pandemics.
PubMed: 37514992
DOI: 10.3390/vaccines11071176 -
Heliyon Feb 2024Vaccination is the most cost-effective method for preventing various infectious diseases. Compared with conventional vaccines, new-generation vaccines, especially... (Review)
Review
Vaccination is the most cost-effective method for preventing various infectious diseases. Compared with conventional vaccines, new-generation vaccines, especially recombinant protein or synthetic peptide vaccines, are safer but less immunogenic than crude inactivated microbial vaccines. The immunogenicity of these vaccines can be enhanced using suitable adjuvants. This is the main reason why adjuvants are of great importance in vaccine development. Several novel human emulsion-based vaccine adjuvants (MF59, AS03) have been approved for clinical use. This paper reviews the research progress on emulsion-based adjuvants and focuses on their mechanism of action. An outlook can be provided for the development of emulsion-based vaccine adjuvants.
PubMed: 38317888
DOI: 10.1016/j.heliyon.2024.e24662 -
Clinical and Experimental Vaccine... Jul 2023One of the most significant medical advancements in human history is the development of vaccines. Progress in vaccine development has always been greatly influenced by... (Review)
Review
One of the most significant medical advancements in human history is the development of vaccines. Progress in vaccine development has always been greatly influenced by scientific human innovation. The main objective of vaccine development would be to acquire sufficient evidence of vaccine effectiveness, immunogenicity, safety, and/or quality to support requests for marketing approval. Vaccines are biological products that enhance the body's defenses against infectious diseases. From the first smallpox vaccine to the latest notable coronavirus disease 2019 nasal vaccine, India has come a long way. The development of numerous vaccines, driven by scientific innovation and advancement, combined with researcher's knowledge, has helped to reduce the global burden of disease and mortality rates. The Drugs and Cosmetics Rules of 1945 and the New Drugs and Clinical Trials Rules of 2019 specify the requirements and guidelines for CMC (chemistry, manufacturing, and controls) for all manufactured and imported vaccines, including those against coronavirus infections. This article provides an overview of the regulation pertaining to the development process, registration, and approval procedures for vaccines, particularly in India, along with their brief history.
PubMed: 37599804
DOI: 10.7774/cevr.2023.12.3.193 -
Human Vaccines & Immunotherapeutics Dec 2024The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) led to urgent actions by innovators, vaccine developers, regulators, and other... (Review)
Review
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) led to urgent actions by innovators, vaccine developers, regulators, and other stakeholders to ensure public access to protective vaccines while maintaining regulatory agency standards. Although development timelines for vaccines against SARS-CoV-2 were much quicker than standard vaccine development timelines, regulatory requirements for efficacy and safety evaluations, including the volume and quality of data collected, were upheld. Rolling review processes supported by sponsors and regulatory authorities enabled rapid assessment of clinical data as well as emergency use authorization. Post-authorization and pharmacovigilance activities enabled the quantity and breadth of post-marketing safety information to quickly exceed that generated from clinical trials. This paper reviews safety and reactogenicity data for the BNT162 vaccine candidates, including BNT162b2 (Comirnaty, Pfizer/BioNTech COVID-19 vaccine) and bivalent variant-adapted BNT162b2 vaccines, from preclinical studies, clinical trials, post-marketing surveillance, and real-world studies, including an unprecedentedly large body of independent evidence.
Topics: Humans; BNT162 Vaccine; COVID-19; COVID-19 Vaccines; Marketing; Pharmacovigilance; SARS-CoV-2; Vaccines, Combined
PubMed: 38407186
DOI: 10.1080/21645515.2024.2315659 -
Nature Communications Jul 2023With the ongoing evolution of the SARS-CoV-2 virus updated vaccines may be needed. We fitted a model linking immunity levels and protection to vaccine effectiveness data...
With the ongoing evolution of the SARS-CoV-2 virus updated vaccines may be needed. We fitted a model linking immunity levels and protection to vaccine effectiveness data from England for three vaccines (Oxford/AstraZeneca AZD1222, Pfizer-BioNTech BNT162b2, Moderna mRNA-1273) and two variants (Delta, Omicron). Our model reproduces the observed sustained protection against hospitalisation and death from the Omicron variant over the first six months following dose 3 with the ancestral vaccines but projects a gradual waning to moderate protection after 1 year. Switching the fourth dose to a variant-matched vaccine against Omicron BA.1/2 is projected to prevent nearly twice as many hospitalisations and deaths over a 1-year period compared to administering the ancestral vaccine. This result is sensitive to the degree to which immunogenicity data can be used to predict vaccine effectiveness and uncertainty regarding the impact that infection-induced immunity (not captured here) may play in modifying future vaccine effectiveness.
Topics: Humans; SARS-CoV-2; BNT162 Vaccine; COVID-19; ChAdOx1 nCoV-19; Vaccine Efficacy; COVID-19 Vaccines
PubMed: 37468463
DOI: 10.1038/s41467-023-39736-3 -
Biostatistics (Oxford, England) Jul 2023Vaccine trials are generally designed to assess efficacy on clinical disease. The vaccine effect on infection, while important both as a proxy for transmission and to...
Vaccine trials are generally designed to assess efficacy on clinical disease. The vaccine effect on infection, while important both as a proxy for transmission and to describe a vaccine's entire effects, requires frequent (e.g., twice a week) longitudinal sampling to capture all infections. Such sampling may not always be feasible. A logistically easy approach is to collect a sample to test for infection at a regularly scheduled visit. Such point or cross-sectional sampling does not permit estimation of classic vaccine efficacy on infection, as long duration infections are sampled with higher probability. Building on work by Rinta-Kokko and others (2009) and Lipsitch and Kahn (2021), we evaluate proxies of the vaccine effect on transmission at a point in time; the vaccine efficacy on prevalent infection and on prevalent viral load, VE$_{\rm PI}$ and VE$_{\rm PVL}$, respectively. Longer infections with higher viral loads should have more transmission potential and prevalent vaccine efficacy naturally captures this aspect. We demonstrate how these parameters obtain from an underlying proportional hazards model for infection and allow for waning efficacy on infection, duration, and viral load. We estimate these parameters based on regression models with either repeated cross-sectional sampling or frequent longitudinal sampling. We evaluate the methods by simulation and analyze a phase III vaccine trial with polymerase chain reaction (PCR) cross-sectional sampling for subclinical infection.
Topics: Humans; Cross-Sectional Studies; Vaccine Efficacy; Vaccines; Computer Simulation
PubMed: 35296878
DOI: 10.1093/biostatistics/kxac008 -
Vaccines Dec 2023Swine enteric coronaviruses (SECs) cause significant economic losses to the pig industry in China. Although many commercialized vaccines against transmissible... (Review)
Review
Swine enteric coronaviruses (SECs) cause significant economic losses to the pig industry in China. Although many commercialized vaccines against transmissible gastroenteritis virus (TGEV) and porcine epidemic diarrhea virus (PEDV) are available, viruses are still widespread. The recent emergence of porcine deltacoronavirus (PDCoV) and swine acute diarrhea syndrome coronavirus (SADS-CoV), for which no vaccines are available, increases the disease burden. In this review, we first introduced the genomic organization and epidemiology of SECs in China. Then, we discussed the current vaccine development and application in China, aiming to provide suggestions for better prevention and control of SECs in China and other countries.
PubMed: 38276670
DOI: 10.3390/vaccines12010011