1
|
Giersing BK, Isbrucker R, Kaslow DC, Cavaleri M, Baylor N, Maiga D, Pavlinac PB, Riddle MS, Kang G, MacLennan CA. Clinical and regulatory development strategies for Shigella vaccines intended for children younger than 5 years in low-income and middle-income countries. Lancet Glob Health 2023; 11:e1819-e1826. [PMID: 37858591 PMCID: PMC10603611 DOI: 10.1016/s2214-109x(23)00421-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 08/28/2023] [Accepted: 08/29/2023] [Indexed: 10/21/2023]
Abstract
Shigellosis causes considerable public health burden, leading to excess deaths as well as acute and chronic consequences, particularly among children living in low-income and middle-income countries (LMICs). Several Shigella vaccine candidates are advancing in clinical trials and offer promise. Although multiple target populations might benefit from a Shigella vaccine, the primary strategic goal of WHO is to accelerate the development and accessibility of safe, effective, and affordable Shigella vaccines that reduce mortality and morbidity in children younger than 5 years living in LMICs. WHO consulted with regulators and policy makers at national, regional, and global levels to evaluate pathways that could accelerate regulatory approval in this priority population. Special consideration was given to surrogate efficacy biomarkers, the role of controlled human infection models, and the establishment of correlates of protection. A field efficacy study in children younger than 5 years in LMICs is needed to ensure introduction in this priority population.
Collapse
Affiliation(s)
- Birgitte K Giersing
- Department of Immunization, Vaccines and Biologicals, World Health Organization, Geneva, Switzerland.
| | - Richard Isbrucker
- Norms and Standards for Biologicals, World Health Organization, Geneva, Switzerland
| | - David C Kaslow
- Essential Medicines and PATH Center for Vaccines Innovation and Access, PATH, Seattle, WA, USA
| | - Marco Cavaleri
- Office of Health Threats and Vaccine Strategy, European Medicines Agency, Amsterdam, Netherlands
| | | | - Diadié Maiga
- Vaccine Regulation, World Health Organization, Regional Office for Africa, Brazzaville, Republic of the Congo
| | - Patricia B Pavlinac
- Global Center for Integrated Health of Women, Adolescents, and Children (Global WACh), Department of Global Health and Department of Epidemiology, University of Washington, Seattle, WA, USA
| | - Mark S Riddle
- Department of Internal Medicine (Community Faculty), University of Nevada, Reno, NV, USA
| | - Gagandeep Kang
- Department of Gastrointestinal Sciences, CMC Vellore, Vellore, India
| | - Calman A MacLennan
- Enterics, Diagnostics, Genomics & Epidemiology, Global Health, Bill & Melinda Gates Foundation, Seattle, WA, USA
| |
Collapse
|
2
|
Libby TE, Delawalla MLM, Al-Shimari F, MacLennan CA, Vannice KS, Pavlinac PB. Consequences of Shigella infection in young children: a systematic review. Int J Infect Dis 2023; 129:78-95. [PMID: 36736579 PMCID: PMC10017352 DOI: 10.1016/j.ijid.2023.01.034] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 01/07/2023] [Accepted: 01/24/2023] [Indexed: 02/02/2023] Open
Abstract
OBJECTIVES We conducted a systematic review of the longitudinal consequences of Shigella infection in children to inform the value proposition for an effective vaccine. METHODS We searched PubMed and Embase for studies published from January 01, 1980 to December 12, 2022 and conducted in low- and middle-income countries that included longitudinal follow-up after Shigella detection among children aged <5 years, irrespective of language. We collected data on all outcomes subsequent to Shigella detection, except mortality. RESULTS Of 2627 papers identified, 52 met inclusion criteria. The median sample size of children aged <5 years was 66 (range 5-2172). Data were collected in 20 countries; 56% (n = 29) of the publications included Bangladesh. The most common outcomes related to diarrhea (n = 20), linear growth (n = 14), and the mean total cost of a Shigella episode (n = 4; range: $ 6.22-31.10). Among children with Shigella diarrhea, 2.9-61.1% developed persistent diarrhea (≥14 days); the persistence was significantly more likely among children who were malnourished, had bloody stool, or had multidrug-resistant Shigella. Cumulative Shigella infections over the first 2 years of life contributed to the greatest loss in length-for-age z-score. CONCLUSION We identified evidence that Shigella is associated with persistent diarrhea, linear growth faltering, and economic impact to the family.
Collapse
Affiliation(s)
- Tanya E Libby
- Department of Epidemiology, University of Washington, Seattle, Washington, USA.
| | | | - Fatima Al-Shimari
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | | | | | - Patricia B Pavlinac
- Department of Global Health, University of Washington, Seattle, Washington, USA
| |
Collapse
|
3
|
Meron-Sudai S, Asato V, Adler A, Bialik A, Goren S, Ariel-Cohen O, Reizis A, Mulard LA, Phalipon A, Cohen D. A Shigella flexneri 2a synthetic glycan-based vaccine induces a long-lasting immune response in adults. NPJ Vaccines 2023; 8:35. [PMID: 36894570 PMCID: PMC9998260 DOI: 10.1038/s41541-023-00624-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 02/09/2023] [Indexed: 03/11/2023] Open
Abstract
Shigella is a leading cause of moderate to severe diarrhea worldwide and of diarrhea-associated deaths in children under 5 years of age in low-and middle-income countries. A vaccine against shigellosis is in high demand. SF2a-TT15, a synthetic carbohydrate-based conjugate vaccine candidate against Shigella flexneri 2a (SF2a) was found safe and strongly immunogenic in adult volunteers. Here, SF2a-TT15 at 10 µg oligosaccharide (OS) vaccine dose is shown to induce a sustained immune response in magnitude and functionality in the majority of volunteers followed up 2 and 3 years post-vaccination. High levels of either one of the humoral parameters as well as the number of specific-IgG memory B-cells determined 3 months after vaccination were good predictors of the durability of the immune response. This study is the first to examine the long-term durability of antibody functionality and memory B-cell response induced by a Shigella vaccine candidate.
Collapse
Affiliation(s)
- Shiri Meron-Sudai
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Valeria Asato
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Amos Adler
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel.,Clinical Microbiology Laboratory, Tel-Aviv Sourasky Medical Center, 6 Weizmann Street, Tel Aviv, 6423906, Israel
| | - Anya Bialik
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Sophy Goren
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Ortal Ariel-Cohen
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Arava Reizis
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Laurence A Mulard
- Institut Pasteur, Université Paris Cité, CNRS UMR3523, Unité de Chimie des Biomolécules, F-75015, Paris, France
| | - Armelle Phalipon
- Institut Pasteur, Innovation Lab. Vaccines, F-75015, Paris, France
| | - Dani Cohen
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel.
| |
Collapse
|
4
|
Plotkin SA. Recent updates on correlates of vaccine-induced protection. Front Immunol 2023; 13:1081107. [PMID: 36776392 PMCID: PMC9912984 DOI: 10.3389/fimmu.2022.1081107] [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: 10/26/2022] [Accepted: 12/02/2022] [Indexed: 02/14/2023] Open
Abstract
Correlates of protection are key for vaccine development against any pathogen. In this paper we summarize recent information about correlates for vaccines against dengue, Ebola, influenza, pneumococcal, respiratory syncytial virus, rotavirus, shigella, tuberculosis and Zika virus.
Collapse
Affiliation(s)
- Stanley A. Plotkin
- University of Pennsylvania, Philadelphia, PA, United States,Consultant, Doylestown, PA, United States,*Correspondence: Stanley A. Plotkin,
| |
Collapse
|
5
|
MacLennan CA, Grow S, Ma LF, Steele AD. The Shigella Vaccines Pipeline. Vaccines (Basel) 2022; 10:vaccines10091376. [PMID: 36146457 PMCID: PMC9504713 DOI: 10.3390/vaccines10091376] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/06/2022] [Accepted: 08/10/2022] [Indexed: 11/22/2022] Open
Abstract
Shigella is the leading cause of global diarrheal deaths that currently lacks a licensed vaccine. Shigellosis drives antimicrobial resistance and leads to economic impact through linear growth faltering. Today, there is a robust pipeline of vaccines in clinical development which are broadly divided into parenteral glycoconjugate vaccines, consisting of O-antigen conjugated to carrier proteins, and oral live attenuated vaccines, which incorporate targeted genetic mutations seeking to optimize the balance between reactogenicity, immunogenicity and ultimately protection. Proof of efficacy has previously been shown with both approaches but for various reasons no vaccine has been licensed to date. In this report, we outline the requirements for a Shigella vaccine and describe the current pipeline in the context of the many candidates that have previously failed or been abandoned. The report refers to papers from individual vaccine developers in this special supplement of Vaccines which is focused on Shigella vaccines. Once readouts of safety and immunogenicity from current trials of lead candidate vaccines among the target population of young children in low- and middle-income countries are available, the likely time to licensure of a first Shigella vaccine will become clearer.
Collapse
|
6
|
Detoxified O-Specific Polysaccharide (O-SP)–Protein Conjugates: Emerging Approach in the Shigella Vaccine Development Scene. Vaccines (Basel) 2022; 10:vaccines10050675. [PMID: 35632431 PMCID: PMC9145086 DOI: 10.3390/vaccines10050675] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/08/2022] [Accepted: 04/17/2022] [Indexed: 11/17/2022] Open
Abstract
Shigella is the second most common cause of moderate to severe diarrhea among children worldwide and of diarrheal disease-associated mortality in young children in low-and middle-income countries. In spite of many years of attempts to develop Shigella vaccines, no licensed vaccines are yet available. Injectable conjugate vaccines made of the detoxified lipopolysaccharide (LPS) of S. flexneri 2a, S. sonnei, and S. dysenteriae type 1 covalently bound to protein carriers were developed in the early 1990s by John B. Robbins and Rachel Schneerson at the US National Institutes of Health. This approach was novel for a disease of the gut mucosa, at a time when live, rationally attenuated oral vaccine strains that intended to mimic Shigella infection and induce a protective local immune response were extensively investigated. Of keystone support to Shigella glycoconjugates development were the findings of a strong association between pre-existent serum IgG antibodies to S. sonnei or S. flexneri 2a LPS and a lower risk of infection with the homologous Shigella serotypes among Israeli soldiers serving in field units. In view of these findings and of the successful development of the pioneering Haemophilus influenzae type b conjugate vaccines, it was hypothesized that protective immunity may be conferred by serum IgG antibodies to the O-Specific Polysaccharide (O-SP) following parenteral delivery of the conjugates. S. sonnei and S. flexneri 2a glycoconjugates induced high levels of serum IgG against the homologous LPS in phase I and II studies in healthy volunteers. The protective efficacy of a S. sonnei detoxified LPS-conjugate was further demonstrated in field trials in young adults (74%) and in children older than three years of age (71%), but not in younger ones. The evaluation of the Shigella conjugates confirmed that IgG antibodies to Shigella LPS are correlates of protection and provided solid basis for the development of a new generation of glycoconjugates and other injectable LPS-based vaccines that are currently in advanced stages of clinical evaluation.
Collapse
|
7
|
Abstract
PURPOSE OF REVIEW This review describes recent findings about the burden of bacterial diarrhoea and its potential complications, newer diagnostics, the emerging threat of multidrug resistance, and the promise of vaccines in development. RECENT FINDINGS Introduction of rotavirus vaccines in over 110 countries has changed the landscape of diarrheal pathogens. In upper middle and high-income countries, the incidence of rotavirus-specific and all-cause gastroenteritis has declined substantially, and norovirus has become the major pathogen in many settings. Bacterial pathogens cause approximately 10-15% of episodes, most often Shigella, nontyphoidal Salmonella (NTS) Campylobacter and Shiga toxin-producing Escherichia coli (STEC). In lower income countries, bacterial pathogens remain a major cause of medically attended diarrhoea with Shigella, Campylobacter and enterotoxigenic Escherichia coli (ETEC) predominating. Multidrug-resistant strains of Shigella, NTS and, Campylobacter have emerged globally requiring judicious use of antibiotics according to current guidance. SUMMARY Management of bacterial diarrhoea includes standard fluid and electrolyte therapy, vigilance for potential complications, and use of antibiotics for children who have moderate-severe illness due to pathogens for which efficacy has been demonstrated, or for those at high risk for severe disease. The threat of multiply resistant strains provides impetus for preventive strategies such as development of vaccines.
Collapse
Affiliation(s)
- Karen L Kotloff
- Division of Infectious Disease and Tropical Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
8
|
Pavlinac PB, Rogawski McQuade ET, Platts-Mills JA, Kotloff KL, Deal C, Giersing BK, Isbrucker RA, Kang G, Ma LF, MacLennan CA, Patriarca P, Steele D, Vannice KS. Pivotal Shigella Vaccine Efficacy Trials-Study Design Considerations from a Shigella Vaccine Trial Design Working Group. Vaccines (Basel) 2022; 10:489. [PMID: 35455238 PMCID: PMC9032541 DOI: 10.3390/vaccines10040489] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 03/15/2022] [Accepted: 03/17/2022] [Indexed: 01/27/2023] Open
Abstract
Vaccine candidates for Shigella are approaching phase 3 clinical trials in the target population of young children living in low- and middle-income countries. Key study design decisions will need to be made to maximize the success of such trials and minimize the time to licensure and implementation. We convened an ad hoc working group to identify the key aspects of trial design that would meet the regulatory requirements to achieve the desired indication of prevention of moderate or severe shigellosis due to strains included in the vaccine. The proposed primary endpoint of pivotal Shigella vaccine trials is the efficacy of the vaccine against the first episode of acute moderate or severe diarrhea caused by the Shigella strains contained within the vaccine. Moderate or severe shigellosis could be defined by a modified Vesikari score with dysentery and molecular detection of vaccine-preventable Shigella strains. This report summarizes the rationale and current data behind these considerations, which will evolve as new data become available and after further review and consultation by global regulators and policymakers.
Collapse
Affiliation(s)
- Patricia B. Pavlinac
- Departments of Global Health and Epidemiology, University of Washington, Seattle, WA 98105, USA
| | | | - James A. Platts-Mills
- Department of Medicine, Infectious Diseases and International Health, University of Virginia, Charlottesville, VA 22908, USA;
| | - Karen L. Kotloff
- Department of Pediatrics, Medicine, Epidemiology, and Public Health, University of Maryland, Baltimore, MD 21201, USA;
| | - Carolyn Deal
- Enteric and Sexually Transmitted Infections Branch, National Institutes of Health, Rockvile, MD 20892, USA;
| | - Birgitte K. Giersing
- Immunization, Vaccines, and Biologicals Department, World Health Organization, 1211 Geneva, Switzerland; (B.K.G.); (R.A.I.)
| | - Richard A. Isbrucker
- Immunization, Vaccines, and Biologicals Department, World Health Organization, 1211 Geneva, Switzerland; (B.K.G.); (R.A.I.)
| | - Gagandeep Kang
- Department of Gastrointestinal Sciences, Christian Medical College, Vellore 632004, Tamil Nadu, India;
| | - Lyou-Fu Ma
- Enteric and Diarrheal Diseases Program Strategy Team, Bill & Melinda Gates Foundation, Seattle, WA 98102, USA; (L.-F.M.); (C.A.M.); (D.S.); (K.S.V.)
| | - Calman A. MacLennan
- Enteric and Diarrheal Diseases Program Strategy Team, Bill & Melinda Gates Foundation, Seattle, WA 98102, USA; (L.-F.M.); (C.A.M.); (D.S.); (K.S.V.)
| | - Peter Patriarca
- Bill & Melinda Gates Medical Research Institute, Cambridge, MA 02139, USA;
| | - Duncan Steele
- Enteric and Diarrheal Diseases Program Strategy Team, Bill & Melinda Gates Foundation, Seattle, WA 98102, USA; (L.-F.M.); (C.A.M.); (D.S.); (K.S.V.)
| | - Kirsten S. Vannice
- Enteric and Diarrheal Diseases Program Strategy Team, Bill & Melinda Gates Foundation, Seattle, WA 98102, USA; (L.-F.M.); (C.A.M.); (D.S.); (K.S.V.)
| |
Collapse
|