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Sumner T, Clark RA, Mukandavire C, Portnoy A, Weerasuriya CK, Bakker R, Scarponi D, Hatherill M, Menzies NA, White RG. Modelling the health and economic impacts ofM72/AS01 E vaccination and BCG-revaccination: Estimates for South Africa. Vaccine 2024; 42:1311-1318. [PMID: 38307747 DOI: 10.1016/j.vaccine.2024.01.072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 01/11/2024] [Accepted: 01/22/2024] [Indexed: 02/04/2024]
Abstract
BACKGROUND Tuberculosis remains a major public health problem in South Africa, with an estimated 300,000 cases and 55,000 deaths in 2021. New tuberculosis vaccines could play an important role in reducing this burden. Phase IIb trials have suggested efficacy of the M72/AS01E vaccine candidate and BCG-revaccination. The potential population impact of these vaccines is unknown. METHODS We used an age-stratified transmission model of tuberculosis, calibrated to epidemiological data from South Africa, to estimate the potential health and economic impact of M72/AS01E vaccination and BCG-revaccination. We simulated M72/AS01E vaccination scenarios over the period 2030-2050 and BCG-revaccination scenarios over the period 2025-2050. We explored a range of product characteristics and delivery strategies. We calculated reductions in tuberculosis cases and deaths and costs and cost-effectiveness from health-system and societal perspectives. FINDINGS M72/AS01E vaccination may have a larger impact than BCG-revaccination, averting approximately 80% more cases and deaths by 2050. Both vaccines were found to be cost-effective or cost saving (compared to no new vaccine) across a range of vaccine characteristics and delivery strategies from both the health system and societal perspective. The impact of M72/AS01E is dependent on the assumed efficacy of the vaccine in uninfected individuals. Extending BCG-revaccination to HIV-infected individuals on ART increased health impact by approximately 15%, but increased health system costs by approximately 70%. INTERPRETATION Our results show that M72/AS01E vaccination or BCG-revaccination could be cost-effective in South Africa. However, there is considerable uncertainty in the estimated impact and costs due to uncertainty in vaccine characteristics and the choice of delivery strategy. FUNDING This work was funded by the Bill & Melinda Gates Foundation (INV-001754). This work used the Cirrus UK National Tier-2 HPC Service at EPCC (https://www.cirrus.ac.uk) funded by the University of Edinburgh and EPSRC (EP/P020267/1).
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Affiliation(s)
- Tom Sumner
- TB Modelling Group and TB Centre, London School of Hygiene and Tropical Medicine, United Kingdom; Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, United Kingdom; Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, United Kingdom.
| | - Rebecca A Clark
- TB Modelling Group and TB Centre, London School of Hygiene and Tropical Medicine, United Kingdom; Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, United Kingdom; Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, United Kingdom; Vaccine Centre, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Christinah Mukandavire
- TB Modelling Group and TB Centre, London School of Hygiene and Tropical Medicine, United Kingdom; Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, United Kingdom; Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Allison Portnoy
- Department of Global Health, Boston University School of Public Health, Boston, USA; Center for Health Decision Science, Harvard T.H. Chan School of Public Health, Boston, USA
| | - Chathika K Weerasuriya
- TB Modelling Group and TB Centre, London School of Hygiene and Tropical Medicine, United Kingdom; Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, United Kingdom; Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Roel Bakker
- TB Modelling Group and TB Centre, London School of Hygiene and Tropical Medicine, United Kingdom; Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, United Kingdom; Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, United Kingdom; KNCV Tuberculosis Foundation, USA
| | - Danny Scarponi
- TB Modelling Group and TB Centre, London School of Hygiene and Tropical Medicine, United Kingdom; Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, United Kingdom; Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Mark Hatherill
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine and Division of Immunology, Department of Pathology, University of Cape Town, South Africa
| | - Nicolas A Menzies
- Center for Health Decision Science, Harvard T.H. Chan School of Public Health, Boston, USA; Department of Global Health and Population, Harvard T.H. Chan School of Public Health, USA
| | - Richard G White
- TB Modelling Group and TB Centre, London School of Hygiene and Tropical Medicine, United Kingdom; Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, United Kingdom; Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, United Kingdom
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Wang H, Wang S, Fang R, Li X, Xing J, Li Z, Song N. Enhancing TB Vaccine Efficacy: Current Progress on Vaccines, Adjuvants and Immunization Strategies. Vaccines (Basel) 2023; 12:38. [PMID: 38250851 PMCID: PMC10820143 DOI: 10.3390/vaccines12010038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 12/27/2023] [Accepted: 12/27/2023] [Indexed: 01/23/2024] Open
Abstract
Tuberculosis (TB) remains a global infectious disease primarily transmitted via respiratory tract infection. Presently, vaccination stands as the primary method for TB prevention, predominantly reliant on the Bacillus Calmette-Guérin (BCG) vaccine. Although it is effective in preventing disseminated diseases in children, its impact on adults is limited. To broaden vaccine protection, efforts are underway to accelerate the development of new TB vaccines. However, challenges arise due to the limited immunogenicity and safety of these vaccines, necessitating adjuvants to bolster their ability to elicit a robust immune response for improved and safer immunization. These adjuvants function by augmenting cellular and humoral immunity against M. tuberculosis antigens via different delivery systems, ultimately enhancing vaccine efficacy. Therefore, this paper reviews and summarizes the current research progress on M. tuberculosis vaccines and their associated adjuvants, aiming to provide a valuable reference for the development of novel TB vaccines and the screening of adjuvants.
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Affiliation(s)
- Hui Wang
- Weifang Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang 261053, China; (H.W.); (S.W.); (R.F.); (X.L.); (J.X.)
| | - Shuxian Wang
- Weifang Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang 261053, China; (H.W.); (S.W.); (R.F.); (X.L.); (J.X.)
| | - Ren Fang
- Weifang Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang 261053, China; (H.W.); (S.W.); (R.F.); (X.L.); (J.X.)
| | - Xiaotian Li
- Weifang Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang 261053, China; (H.W.); (S.W.); (R.F.); (X.L.); (J.X.)
| | - Jiayin Xing
- Weifang Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang 261053, China; (H.W.); (S.W.); (R.F.); (X.L.); (J.X.)
| | - Zhaoli Li
- SAFE Pharmaceutical Technology Co., Ltd., Beijing 100000, China
| | - Ningning Song
- Weifang Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang 261053, China; (H.W.); (S.W.); (R.F.); (X.L.); (J.X.)
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Wang P, Cai Y, Zhang G, Jiang L, Li Y. Establishment of an indirect ELISA for Mycobacterium tuberculosis MTB39A protein antibody. Appl Microbiol Biotechnol 2023; 107:6339-6349. [PMID: 37597020 PMCID: PMC10560182 DOI: 10.1007/s00253-023-12715-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 07/24/2023] [Accepted: 07/29/2023] [Indexed: 08/21/2023]
Abstract
The MTB39A protein is a member of the unique Mycobacterium tuberculosis (MTB) PE/PPE protein family and is the main candidate for tuberculosis (TB) diagnosis. The aim of this study was to establish a novel indirect ELISA (iELISA) method that uses antibodies against MTB. The MTB39A gene sequence was synthesized according to the MTB39A nucleotide sequence of the MTB H37Rv strain (GenBank accession number: NC_000962.3) and cloned into the pET28a( +) vector. After correct sequencing, it was transferred to Escherichia coli BL21 (DE3) receptor cells for expression and purification, and the purified recombinant protein was identified by SDS-PAGE and western blotting. The purified MTB39A protein was used as the capture antibody, and a rabbit polyclonal antibody against the MTB MTB39A protein was used as the detection antibody to establish an indirect ELISA method. The ELISA conditions were optimized, and the optimal coating concentration of the MTB39A antigen was determined to be 0.5 μg/mL. The optimal dilution of MTB39A rabbit polyclonal antibody was 1:4096, and the optimal dilution of HRP-goat anti-rabbit IgG was 1:4000. The results showed that this indirect ELISA method has high sensitivity, specificity and efficacy for MTB39A protein detection. Moreover, this indirect ELISA method has optimal stability and can be used for the initial detection of MTB antibodies in clinical human and bovine serum samples. The establishment of this assay provides a new method for the rapid diagnosis of MTB and technical support for the prevention and control of tuberculosis. KEY POINTS: • MTB MTB39A protein was expressed in a prokaryotic expression system. • Rabbit polyclonal antibody against MTB39A was prepared. • To establish an iELISA based on the MTB39A protein for the detection of MTB antibodies.
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Affiliation(s)
- Pu Wang
- School of Life Sciences, Ningxia University, Yinchuan, China
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in Western China, Ningxia University, Yinchuan, China
| | - Yurong Cai
- School of Life Sciences, Ningxia University, Yinchuan, China
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in Western China, Ningxia University, Yinchuan, China
| | - Gang Zhang
- School of Life Sciences, Ningxia University, Yinchuan, China
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in Western China, Ningxia University, Yinchuan, China
| | - Lingling Jiang
- School of Life Sciences, Ningxia University, Yinchuan, China
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in Western China, Ningxia University, Yinchuan, China
| | - Yong Li
- School of Life Sciences, Ningxia University, Yinchuan, China.
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in Western China, Ningxia University, Yinchuan, China.
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Mao JJ, Zang X, Yue WL, Zhai PY, Zhang Q, Li CH, Zhuang X, Liu M, Qin G. Population-level health and economic impacts of introducing Vaccae vaccination in China: a modelling study. BMJ Glob Health 2023; 8:bmjgh-2023-012306. [PMID: 37257938 DOI: 10.1136/bmjgh-2023-012306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 05/06/2023] [Indexed: 06/02/2023] Open
Abstract
INTRODUCTION Given the ageing epidemic of tuberculosis (TB), China is facing an unprecedented opportunity provided by the first clinically approved next-generation TB vaccine Vaccae, which demonstrated 54.7% efficacy for preventing reactivation from latent infection in a phase III trial. We aim to assess the population-level health and economic impacts of introducing Vaccae vaccination to inform policy-makers. METHODS We evaluated a potential national Vaccae vaccination programme in China initiated in 2024, assuming 20 years of protection, 90% coverage and US$30/dose government contract price. An age-structured compartmental model was adapted to simulate three strategies: (1) no Vaccae; (2) mass vaccination among people aged 15-74 years and (3) targeted vaccination among older adults (60 years). Cost analyses were conducted from the healthcare sector perspective, discounted at 3%. RESULTS Considering postinfection efficacy, targeted vaccination modestly reduced TB burden (~20%), preventing cumulative 8.01 (95% CI 5.82 to 11.8) million TB cases and 0.20 (0.17 to 0.26) million deaths over 2024-2050, at incremental cost-effectiveness ratio of US$4387 (2218 to 10 085) per disability adjusted life year averted. The implementation would require a total budget of US$22.5 (17.6 to 43.4) billion. In contrast, mass vaccination had a larger bigger impact on the TB epidemic, but the overall costs remained high. Although both preinfection and postinfection vaccine efficacy type might have a maximum impact (>40% incidence rate reduction in 2050), it is important that the vaccine price does not exceed US$5/dose. CONCLUSION Vaccae represents a robust and cost-effective choice for TB epidemic control in China. This study may facilitate the practice of evidence-based strategy plans for TB vaccination and reimbursement decision making.
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Affiliation(s)
- Jun-Jie Mao
- Joint Division of Clinical Epidemiology, Affilated Hosptial of Nantong University, School of Public Health of Nantong University, Nantong, Jiangsu, China
| | - Xiao Zang
- Division of Health Policy and Management, University of Minnesota Twin Cities, Minneapolis, Minnesota, USA
| | - Wan-Lu Yue
- Department of Infectious Diseases, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong, Jiangsu, China
| | - Pei-Yao Zhai
- Department of Infectious Diseases, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong, Jiangsu, China
| | - Qiong Zhang
- Research Centre of Clinical Medicine, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China
| | - Chun-Hu Li
- Joint Division of Clinical Epidemiology, Affilated Hosptial of Nantong University, School of Public Health of Nantong University, Nantong, Jiangsu, China
| | - Xun Zhuang
- Department of Epidemiology and Biostatistics, School of Public Health of Nantong University, Nantong, Jiangsu, China
| | - Min Liu
- Department of Epidemiology and Biostatistics, School of Public Health of Peking University, Beijing, China
| | - Gang Qin
- Joint Division of Clinical Epidemiology, Affilated Hosptial of Nantong University, School of Public Health of Nantong University, Nantong, Jiangsu, China
- National Key Clinical Construction Specialty-Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China
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A Multistage Antigen Complex Epera013 Promotes Efficient and Comprehensive Immune Responses in BALB/c Mice. Vaccines (Basel) 2023; 11:vaccines11030609. [PMID: 36992193 DOI: 10.3390/vaccines11030609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 02/27/2023] [Accepted: 02/28/2023] [Indexed: 03/10/2023] Open
Abstract
Tuberculosis (TB) remains a serious global health problem. Despite the widespread use of the Mycobacterium bovis bacillus Calmette-Guerin (BCG) vaccine, the primary factor for the TB pandemic and deaths is adult TB, which mainly result from endogenous reactivation of latent Mycobacterium tuberculosis (MTB) infection. Improved new TB vaccines with eligible safety and long-lasting protective efficacy remains a crucial step toward the prevention and control of TB. In this study, five immunodominant antigens, including three early secreted antigens and two latency associated antigens, were used to construct a single recombinant fusion protein (Epera013f) and a protein mixture (Epera013m). When formulated with aluminum adjuvant, the two subunit vaccines Epera013m and Epera013f were administered to BALB/c mice. The humoral immune responses, cellular responses and MTB growth inhibiting capacity elicited after Epera013m and Epera013f immunization were analyzed. In the present study, we demonstrated that both the Epera013f and Epera013m were capable of inducing a considerable immune response and protective efficacy against H37Rv infection compared with BCG groups. In addition, Epera013f generated a more comprehensive and balanced immune status, including Th1, Th2 and innate immune response, over Epera013f and BCG. The multistage antigen complex Epera013f possesses considerable immunogenicity and protective efficacy against MTB infection ex vivo indicating its potential and promising applications in further TB vaccine development.
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Meeting report: 6th Global Forum on Tuberculosis Vaccines, 22–25 February 2022, Toulouse, France. Vaccine X 2023. [DOI: 10.1016/j.jvacx.2023.100267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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Andongma BT, Huang Y, Chen F, Tang Q, Yang M, Chou SH, Li X, He J. In silico design of a promiscuous chimeric multi-epitope vaccine against Mycobacterium tuberculosis. Comput Struct Biotechnol J 2023; 21:991-1004. [PMID: 36733703 PMCID: PMC9883148 DOI: 10.1016/j.csbj.2023.01.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 01/15/2023] [Accepted: 01/15/2023] [Indexed: 01/18/2023] Open
Abstract
Tuberculosis (TB) is a global health threat, killing approximately 1.5 million people each year. The eradication of Mycobacterium tuberculosis, the main causative agent of TB, is increasingly challenging due to the emergence of extensive drug-resistant strains. Vaccination is considered an effective way to protect the host from pathogens, but the only clinically approved TB vaccine, Bacillus Calmette-Guérin (BCG), has limited protection in adults. Multi-epitope vaccines have been found to enhance immunity to diseases by selectively combining epitopes from several candidate proteins. This study aimed to design a multi-epitope vaccine against TB using an immuno-informatics approach. Through functional enrichment, we identified eight proteins secreted by M. tuberculosis that are either required for pathogenesis, secreted into extracellular space, or both. We then analyzed the epitopes of these proteins and selected 16 helper T lymphocyte epitopes with interferon-γ inducing activity, 15 cytotoxic T lymphocyte epitopes, and 10 linear B-cell epitopes, and conjugated them with adjuvant and Pan HLA DR-binding epitope (PADRE) using appropriate linkers. Moreover, we predicted the tertiary structure of this vaccine, its potential interaction with Toll-Like Receptor-4 (TLR4), and the immune response it might elicit. The results showed that this vaccine had a strong affinity for TLR4, which could significantly stimulate CD4+ and CD8+ cells to secrete immune factors and B lymphocytes to secrete immunoglobulins, so as to obtain good humoral and cellular immunity. Overall, this multi-epitope protein was predicted to be stable, safe, highly antigenic, and highly immunogenic, which has the potential to serve as a global vaccine against TB.
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Affiliation(s)
- Binda T. Andongma
- State Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China
| | - Yazheng Huang
- State Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China
| | - Fang Chen
- State Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China
| | - Qing Tang
- State Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China
| | - Min Yang
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430070, PR China
| | - Shan-Ho Chou
- State Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China
| | - Xinfeng Li
- State Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China,CAS Key Laboratory of Special Pathogens and Biosafety, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China,Correspondence to: The State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, No. 1 Shizishan Street, Wuhan, Hubei 430070, PR China.
| | - Jin He
- State Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China,Correspondence to: The State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, No. 1 Shizishan Street, Wuhan, Hubei 430070, PR China.
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Jayawardana S, Weerasuriya CK, Pelzer PT, Seeley J, Harris RC, Tameris M, Tait D, White RG, Asaria M. Feasibility of novel adult tuberculosis vaccination in South Africa: a cost-effectiveness and budget impact analysis. NPJ Vaccines 2022; 7:138. [DOI: 10.1038/s41541-022-00554-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 10/10/2022] [Indexed: 11/09/2022] Open
Abstract
AbstractEarly trials of novel vaccines against tuberculosis (TB) in adults have suggested substantial protection against TB. However, little is known about the feasibility and affordability of rolling out such vaccines in practice. We conducted expert interviews to identify plausible vaccination implementation strategies for the novel M72/AS01E vaccine candidate. The strategies were defined in terms of target population, coverage, vaccination schedule and delivery mode. We modelled these strategies to estimate long-term resource requirements and health benefits arising from vaccination over 2025–2050. We presented these to experts who excluded strategies that were deemed infeasible, and estimated cost-effectiveness and budget impact for each remaining strategy. The four strategies modelled combined target populations: either everyone aged 18–50, or all adults living with HIV, with delivery strategies: either a mass campaign followed by routine vaccination of 18-year olds, or two mass campaigns 10 years apart. Delivering two mass campaigns to all 18–50-year olds was found to be the most cost-effective strategy conferring the greatest net health benefit of 1.2 million DALYs averted having a probability of being cost-effective of 65–70%. This strategy required 38 million vaccine courses to be delivered at a cost of USD 507 million, reducing TB-related costs by USD 184 million while increasing ART costs by USD 79 million. A suitably designed adult TB vaccination programme built around novel TB vaccines is likely to be cost-effective and affordable given the resource and budget constraints in South Africa.
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Larsen SE, Williams BD, Rais M, Coler RN, Baldwin SL. It Takes a Village: The Multifaceted Immune Response to Mycobacterium tuberculosis Infection and Vaccine-Induced Immunity. Front Immunol 2022; 13:840225. [PMID: 35359957 PMCID: PMC8960931 DOI: 10.3389/fimmu.2022.840225] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 02/08/2022] [Indexed: 11/18/2022] Open
Abstract
Despite co-evolving with humans for centuries and being intensely studied for decades, the immune correlates of protection against Mycobacterium tuberculosis (Mtb) have yet to be fully defined. This lapse in understanding is a major lag in the pipeline for evaluating and advancing efficacious vaccine candidates. While CD4+ T helper 1 (TH1) pro-inflammatory responses have a significant role in controlling Mtb infection, the historically narrow focus on this cell population may have eclipsed the characterization of other requisite arms of the immune system. Over the last decade, the tuberculosis (TB) research community has intentionally and intensely increased the breadth of investigation of other immune players. Here, we review mechanistic preclinical studies as well as clinical anecdotes that suggest the degree to which different cell types, such as NK cells, CD8+ T cells, γ δ T cells, and B cells, influence infection or disease prevention. Additionally, we categorically outline the observed role each major cell type plays in vaccine-induced immunity, including Mycobacterium bovis bacillus Calmette-Guérin (BCG). Novel vaccine candidates advancing through either the preclinical or clinical pipeline leverage different platforms (e.g., protein + adjuvant, vector-based, nucleic acid-based) to purposefully elicit complex immune responses, and we review those design rationales and results to date. The better we as a community understand the essential composition, magnitude, timing, and trafficking of immune responses against Mtb, the closer we are to reducing the severe disease burden and toll on human health inflicted by TB globally.
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Affiliation(s)
- Sasha E. Larsen
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle Children's Hospital, Seattle, WA, United States
| | - Brittany D. Williams
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle Children's Hospital, Seattle, WA, United States,Department of Global Health, University of Washington, Seattle, WA, United States
| | - Maham Rais
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle Children's Hospital, Seattle, WA, United States
| | - Rhea N. Coler
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle Children's Hospital, Seattle, WA, United States,Department of Global Health, University of Washington, Seattle, WA, United States,Department of Pediatrics, University of Washington School of Medicine, Seattle, WA, United States
| | - Susan L. Baldwin
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle Children's Hospital, Seattle, WA, United States,*Correspondence: Susan L. Baldwin,
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