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| ● Introduction ● Technology platforms (see) ● Diseases (see) ● SARS-CoV-2 (see) ● HIV infection (see) ● Influenza (see) ● Other diseases (see) ● Global distribution of R&D (see) ● Final considerations Factors (see) ● For more information about this website, bibliography and recommended links (see) |
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| ● Provides an overview of the development and clinical research status of new vaccines. ● At the beginning of 2023, a total of 966 candidate vaccine products are under investigation. ● Recombinant protein vaccines account for the largest proportion of products under development, accounting for 22%. The second group of products investigated was RNA and DNA (18%), followed by inactivated vaccines and viral vectors. ● SARS-CoV-2 (246; 25%), influenza (104; 11%) and HIV (84; 9%) account for almost half of the vaccine candidates under study. ● Vaccine development is mainly concentrated in the United States (355 product candidates; 36.7%), China (271; 28.1%)) and Western Europe (144; 14.9%). In the United States, nucleic acid vaccines dominate, in China, inactivated vaccines dominate, and in Europe, recombinant vaccines and viral vector vaccines dominate. ● HIV and malaria drug candidates are developed primarily by academic or other non-profit organizations. |
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introduce
Vaccines have had and will continue to have an extraordinary impact on public health, and the COVID-19 pandemic has highlighted their importance. This article reviews a publication that reviews the global status of new vaccine (preventive vaccines for infectious diseases) development in early 2023.
Vaccine product candidates are classified into two broad categories: the technology platform that supports them and the infectious diseases they are designed to prevent. Only 966 candidate molecules in clinical studies were included (there are estimated to be thousands of molecules in various stages of preclinical development).
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Technology platform
As of early 2023, the global vaccine R&D landscape includes 966 product candidates, of which 23% (220) Traditional inactivated or attenuated vaccines (See attached figure (a)). Advances in molecular technology have led to the development of other platforms, such as recombinant protein vaccines, nucleic acid vaccines, and viral vector vaccines. Products with insufficient information were classified into the “Unknown” group, and those that did not belong to the main groups were classified into the “Other” group.
this Recombinant protein vaccine They account for the largest share of the portfolio at 22% (215 candidates; see Figure (1b)), thanks to their well-known safety, manufacturing process stability and flexibility. Nearly 100 recombinant vaccine candidates are in Phase I development, the largest number of any platform at this stage.
Successful launch of mRNA vaccine against SARS-CoV-2 boosts Nucleic acid vaccine, which includes RNA and DNA vaccines. Such platforms currently make up the second largest portion of the entire pipeline, accounting for 18% (173 candidate platforms). Due to the flexibility of these platforms in developing vaccine candidates against pathogens with high variability in target antigens, many vaccine candidates are being developed against such pathogens, including SARS-CoV-2 (95 vaccine candidates), influenza (24 candidates vaccines) and HIV (21 candidates).
this viral vector vaccine (133 candidates; 14%) have also experienced rapid development in recent years due to their potential to induce robust and long-lasting immune responses. Various types of viral vectors are being used, including adenovirus, retrovirus, lentivirus, and poxvirus. In particular, adenoviral vectors (82 candidates) have been widely used in the development of vaccines for diseases such as Ebola, HIV, influenza, and SARS-CoV-2. To circumvent limitations of existing immunity to adenovirus type 5 (Ad5), multiple adenovirus serotypes were developed, such as Ad26, Ad35, and Ad11.
this conjugate vaccinewhich is the next group (109 candidates; 11%), is for meningococci, pneumococci and Haemophilus influenza. These vaccines are based on the covalent linkage of immunogenic protein carriers (mainly tetanus toxoid, diphtheria toxoid or group B meningococcal outer membrane proteins) to polysaccharides or capsular peptides to improve immunogenicity and stability.
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disease
The top three diseases in vaccine development are caused by viruses: SARS-CoV-2 (246 candidates; 25%), influenza (104 candidates; 11%), and HIV (84 candidates; 9% ) (see attached figures (c and d))).
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SARS-CoV-2
In addition to the more than 50 vaccines that have received marketing approval or emergency use authorization (not included in this report), an additional 64 vaccine candidates have entered Phase III or have submitted regulatory applications, 47% of which are mRNA vaccines. Currently, at least 14 nasal vaccines are under development, which are expected to enhance the immunity of the respiratory mucosa and further reduce transmission.
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HIV infection
The high variability of viral genomes and high glycosylation levels of HIV envelope glycoproteins (gp) often induce immune evasion, hindering the successful development of HIV vaccines. Today, however, there is great promise in stimulating the production of broadly neutralizing antibodies (bnAbs) by targeting conserved regions of envelope proteins that differ only slightly between HIV strains, such as gp160, gp41, and gp120. Novel platforms such as viral vectors and mRNA offer a promising avenue for HIV vaccine development. For example, two mRNA vaccines that induce bnAb production are currently in phase I trials (NCT05001373).
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influenza
In contrast to the dominance of new technologies in HIV vaccine development, 40% of influenza vaccine candidates are inactivated vaccines (see Figure (d)). Given the variety of influenza virus subtypes, more and more universal vaccines are being developed to reduce the need for frequent vaccinations. These vaccines are designed based on highly conserved epitopes on viral hemagglutinin, neuraminidase, or other proteins. As of the end of 2022, six universal influenza vaccine candidates are in Phase III trials.
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other illnesses
In addition to the three diseases mentioned above, a large number of vaccines are in development against respiratory syncytial virus (RSV; 31 vaccine candidates; 3%), supported by recent advances targeting the stabilized pre-F protein. In particular, two recombinant protein vaccines, PF-06928316 and GSK3844766A, achieved >80% protection in phase III trials and were approved by regulatory agencies (EMA and FDA) in 2023.An mRNA Vaccine (mRNA-1345) Receives FDA Breakthrough Also Shows >80 Protection Post-Therapeutic Designation·% in Phase III trials.
Non-viral pathogens such as malaria (57 candidates; 6%) and pneumococci (40 candidates; 4%) also represent important areas of interest (see accompanying figures (c and d)). Conjugate vaccines are the main approach for pneumococcal vaccines, while recombinant proteins and viral vectors are the main platforms for malaria vaccines.
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R&D global distribution
Vaccine research and development is mainly concentrated in the United States (355 candidate products), China (271) and Western Europe (144) (see attached figure (a)). There are some differences in technology platform preferences across these regions; take the United States as an example.·The United States has more nucleic acid vaccines, China has more inactivated vaccines, and fewer viral vector vaccines. The majority (68%) of candidates were developed independently or in partnership with private companies/industry, while 25% were developed by academic or other not-for-profit organizations (see accompanying figure (b)). In particular, HIV and malaria drug candidates are developed primarily by academic or other nonprofit organizations.
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final considerations
The success of vaccine development depends largely on the identification of effective antigens and the use of appropriate technology platforms. Furthermore, international cooperation and concerted efforts are crucial to effectively achieve these goals. The COVID-19 pandemic has highlighted the importance of global cooperation in responding to public health emergencies and demonstrated the potential benefits of sharing resources and expertise to accelerate vaccine development and deployment. This includes sharing scientific resources and expertise, collaborating on research and development, and establishing coordination mechanisms to prepare for and respond to outbreaks or emerging diseases.
Recent experience highlights the need for adequate funding, research process flexibility, new forms of governance and priority setting, without reducing the value of need in neglected diseases (Yarney G, BMJ 2021).
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For more information please visit this website
Bibliography and recommended links
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