User login
Seeking new vaccines against whooping cough: The PERISCOPE project
Although there is an effective vaccine against Bordetella pertussis, whooping cough remains a leading cause of death. Cases are increasing, and scientists face challenges in developing new vaccines.
In a key research session at the start of the annual meeting of the European Society for Paediatric Infectious Diseases, held virtually this year, Dimitri Diavatopoulos, PhD, associate professor at the Radboud University Medical Centre Nijmegen, the Netherlands, summarized the pertussis vaccination problem and what the Pertussis Correlates of Protection Europe (PERISCOPE) project seeks to achieve. Dr. Diavatopoulos has a longstanding interest in pertussis and immunity and will soon take over as the scientific coordinator of PERISCOPE.
Pertussis is a highly contagious infectious disease that causes uncontrollable coughing. The disease begins with an atypical cough and rhinorrhea before entering a paroxysmal stage characterized by cyanosis, lymphocytosis, vomiting, and whoops. Generally, fever is absent and coughing increases at night. Finally, after weeks to months, the patient enters a convalescent stage. The World Health Organization estimates that there are 16 million pertussis cases annually and approximately 195,000 deaths in children. Most cases are caused by Bordetella pertussis and are preventable by vaccination.
In the United States, following the introduction of a national immunization program using a whole-cell vaccine in the 1950s, cases fell significantly. After a lag phase, the adoption of an acellular vaccine in the United States in 1997 and the Netherlands in 2005 – usually in combination with diphtheria and tetanus via DTaP – saw an increase in case numbers. Dr. Diavatopoulos stated that control is no longer as good, compared with other infectious diseases prevented by the MMR vaccine, such as mumps, measles, and rubella.
In the face of increasing numbers, how do we move to the next generation of vaccines to improve control? There are several barriers to licensure, including the following:
• Universal recommendation for pertussis prevention means that more than 90% of the population will have received DTaP (usually in combination with polio and Haemophilus influenzae B) and be protected for several years after vaccination.
• Because DTaP vaccines are only efficacious for a limited time, the problem is not immediately apparent.
• Pertussis epidemics are cyclical, occurring every 3-5 years. These peaks and troughs complicate the development of epidemiological studies.
What this means is that large-scale Phase III efficacy studies, in which disease is used as the endpoint, are not feasible. Also, formal correlates of protection have not been identified.
The PERISCOPE Project started in March 2016 and is designed to respond to some of these issues. Funding is made available by a public private consortium involving the Bill & Melinda Gates foundation, the European Union, and European Federation of Pharmaceutical Industries and Associations (EFPIA) partners, and in this case, GlaxoSmithKline and Sanofi Pasteur. In total, there are 22 partners in this project.
The strategic objectives of this partnership include the following:
• Foster expertise and increase capacity in Europe to evaluate new pertussis vaccines both in clinical and preclinical models.
• Identify early biomarkers of long-lasting protective immunity to pertussis in humans. (This step will accelerate and de-risk clinical development of next generation pertussis vaccines.)
• Investigate the impact of maternal vaccination on infant response to pertussis vaccination.
The problem is that there is no one single study design that addresses all questions about the pertussis vaccine. For example, in PERISCOPE, the results of preclinical studies using the baboon or mouse models and addressing disease and colonization endpoints or immunogenicity do not perfectly model human infection and disease.
By comparison, controlled human infection studies provide information on colonization but not disease endpoints. Such studies, however, do provide information on immunogenicity endpoints. Also available are booster vaccination studies and infant vaccination studies providing data on immunogenicity, as well as safety information.
Finally, there are patient studies, such as household contact studies where immunogenicity can be correlated to disease endpoints. From these studies, it will be seen that what is needed is integration of evidence from clinical and preclinical studies to support a new vaccine registration.
PERISCOPE addresses these issues by developing novel, functional antibody and cellular assays and employing cutting-edge methods to characterize innate immune responses and cell-mediated systemic and mucosal immunity. PERISCOPE combines two major industrial partners with public researchers from academic and public health institutes and small and medium-sized enterprises with expertise in clinical trials, vaccinology, immunology, molecular microbiology, challenge models, and bioinformatics.
Andrew Gorringe, PhD, from Public Health England and the Research and Development Institute at Porton Down, Wiltshire, England, said, “Vaccines have greatly reduced the incidence of pertussis, but it remains the most prevalent ‘vaccine preventable’ disease. This is an exciting period for pertussis vaccine research as we find new ways to understand the immunity that protects from both infection and disease. The PERISCOPE project provides a collaborative environment that combines expertise across Europe to provide a route to the development of new, more effective vaccines.”
GSK and Sanofi Pasteur have cofunded the PERISCOPE Project. Dr. Diavatopoulos made no other financial disclosures.
Although there is an effective vaccine against Bordetella pertussis, whooping cough remains a leading cause of death. Cases are increasing, and scientists face challenges in developing new vaccines.
In a key research session at the start of the annual meeting of the European Society for Paediatric Infectious Diseases, held virtually this year, Dimitri Diavatopoulos, PhD, associate professor at the Radboud University Medical Centre Nijmegen, the Netherlands, summarized the pertussis vaccination problem and what the Pertussis Correlates of Protection Europe (PERISCOPE) project seeks to achieve. Dr. Diavatopoulos has a longstanding interest in pertussis and immunity and will soon take over as the scientific coordinator of PERISCOPE.
Pertussis is a highly contagious infectious disease that causes uncontrollable coughing. The disease begins with an atypical cough and rhinorrhea before entering a paroxysmal stage characterized by cyanosis, lymphocytosis, vomiting, and whoops. Generally, fever is absent and coughing increases at night. Finally, after weeks to months, the patient enters a convalescent stage. The World Health Organization estimates that there are 16 million pertussis cases annually and approximately 195,000 deaths in children. Most cases are caused by Bordetella pertussis and are preventable by vaccination.
In the United States, following the introduction of a national immunization program using a whole-cell vaccine in the 1950s, cases fell significantly. After a lag phase, the adoption of an acellular vaccine in the United States in 1997 and the Netherlands in 2005 – usually in combination with diphtheria and tetanus via DTaP – saw an increase in case numbers. Dr. Diavatopoulos stated that control is no longer as good, compared with other infectious diseases prevented by the MMR vaccine, such as mumps, measles, and rubella.
In the face of increasing numbers, how do we move to the next generation of vaccines to improve control? There are several barriers to licensure, including the following:
• Universal recommendation for pertussis prevention means that more than 90% of the population will have received DTaP (usually in combination with polio and Haemophilus influenzae B) and be protected for several years after vaccination.
• Because DTaP vaccines are only efficacious for a limited time, the problem is not immediately apparent.
• Pertussis epidemics are cyclical, occurring every 3-5 years. These peaks and troughs complicate the development of epidemiological studies.
What this means is that large-scale Phase III efficacy studies, in which disease is used as the endpoint, are not feasible. Also, formal correlates of protection have not been identified.
The PERISCOPE Project started in March 2016 and is designed to respond to some of these issues. Funding is made available by a public private consortium involving the Bill & Melinda Gates foundation, the European Union, and European Federation of Pharmaceutical Industries and Associations (EFPIA) partners, and in this case, GlaxoSmithKline and Sanofi Pasteur. In total, there are 22 partners in this project.
The strategic objectives of this partnership include the following:
• Foster expertise and increase capacity in Europe to evaluate new pertussis vaccines both in clinical and preclinical models.
• Identify early biomarkers of long-lasting protective immunity to pertussis in humans. (This step will accelerate and de-risk clinical development of next generation pertussis vaccines.)
• Investigate the impact of maternal vaccination on infant response to pertussis vaccination.
The problem is that there is no one single study design that addresses all questions about the pertussis vaccine. For example, in PERISCOPE, the results of preclinical studies using the baboon or mouse models and addressing disease and colonization endpoints or immunogenicity do not perfectly model human infection and disease.
By comparison, controlled human infection studies provide information on colonization but not disease endpoints. Such studies, however, do provide information on immunogenicity endpoints. Also available are booster vaccination studies and infant vaccination studies providing data on immunogenicity, as well as safety information.
Finally, there are patient studies, such as household contact studies where immunogenicity can be correlated to disease endpoints. From these studies, it will be seen that what is needed is integration of evidence from clinical and preclinical studies to support a new vaccine registration.
PERISCOPE addresses these issues by developing novel, functional antibody and cellular assays and employing cutting-edge methods to characterize innate immune responses and cell-mediated systemic and mucosal immunity. PERISCOPE combines two major industrial partners with public researchers from academic and public health institutes and small and medium-sized enterprises with expertise in clinical trials, vaccinology, immunology, molecular microbiology, challenge models, and bioinformatics.
Andrew Gorringe, PhD, from Public Health England and the Research and Development Institute at Porton Down, Wiltshire, England, said, “Vaccines have greatly reduced the incidence of pertussis, but it remains the most prevalent ‘vaccine preventable’ disease. This is an exciting period for pertussis vaccine research as we find new ways to understand the immunity that protects from both infection and disease. The PERISCOPE project provides a collaborative environment that combines expertise across Europe to provide a route to the development of new, more effective vaccines.”
GSK and Sanofi Pasteur have cofunded the PERISCOPE Project. Dr. Diavatopoulos made no other financial disclosures.
Although there is an effective vaccine against Bordetella pertussis, whooping cough remains a leading cause of death. Cases are increasing, and scientists face challenges in developing new vaccines.
In a key research session at the start of the annual meeting of the European Society for Paediatric Infectious Diseases, held virtually this year, Dimitri Diavatopoulos, PhD, associate professor at the Radboud University Medical Centre Nijmegen, the Netherlands, summarized the pertussis vaccination problem and what the Pertussis Correlates of Protection Europe (PERISCOPE) project seeks to achieve. Dr. Diavatopoulos has a longstanding interest in pertussis and immunity and will soon take over as the scientific coordinator of PERISCOPE.
Pertussis is a highly contagious infectious disease that causes uncontrollable coughing. The disease begins with an atypical cough and rhinorrhea before entering a paroxysmal stage characterized by cyanosis, lymphocytosis, vomiting, and whoops. Generally, fever is absent and coughing increases at night. Finally, after weeks to months, the patient enters a convalescent stage. The World Health Organization estimates that there are 16 million pertussis cases annually and approximately 195,000 deaths in children. Most cases are caused by Bordetella pertussis and are preventable by vaccination.
In the United States, following the introduction of a national immunization program using a whole-cell vaccine in the 1950s, cases fell significantly. After a lag phase, the adoption of an acellular vaccine in the United States in 1997 and the Netherlands in 2005 – usually in combination with diphtheria and tetanus via DTaP – saw an increase in case numbers. Dr. Diavatopoulos stated that control is no longer as good, compared with other infectious diseases prevented by the MMR vaccine, such as mumps, measles, and rubella.
In the face of increasing numbers, how do we move to the next generation of vaccines to improve control? There are several barriers to licensure, including the following:
• Universal recommendation for pertussis prevention means that more than 90% of the population will have received DTaP (usually in combination with polio and Haemophilus influenzae B) and be protected for several years after vaccination.
• Because DTaP vaccines are only efficacious for a limited time, the problem is not immediately apparent.
• Pertussis epidemics are cyclical, occurring every 3-5 years. These peaks and troughs complicate the development of epidemiological studies.
What this means is that large-scale Phase III efficacy studies, in which disease is used as the endpoint, are not feasible. Also, formal correlates of protection have not been identified.
The PERISCOPE Project started in March 2016 and is designed to respond to some of these issues. Funding is made available by a public private consortium involving the Bill & Melinda Gates foundation, the European Union, and European Federation of Pharmaceutical Industries and Associations (EFPIA) partners, and in this case, GlaxoSmithKline and Sanofi Pasteur. In total, there are 22 partners in this project.
The strategic objectives of this partnership include the following:
• Foster expertise and increase capacity in Europe to evaluate new pertussis vaccines both in clinical and preclinical models.
• Identify early biomarkers of long-lasting protective immunity to pertussis in humans. (This step will accelerate and de-risk clinical development of next generation pertussis vaccines.)
• Investigate the impact of maternal vaccination on infant response to pertussis vaccination.
The problem is that there is no one single study design that addresses all questions about the pertussis vaccine. For example, in PERISCOPE, the results of preclinical studies using the baboon or mouse models and addressing disease and colonization endpoints or immunogenicity do not perfectly model human infection and disease.
By comparison, controlled human infection studies provide information on colonization but not disease endpoints. Such studies, however, do provide information on immunogenicity endpoints. Also available are booster vaccination studies and infant vaccination studies providing data on immunogenicity, as well as safety information.
Finally, there are patient studies, such as household contact studies where immunogenicity can be correlated to disease endpoints. From these studies, it will be seen that what is needed is integration of evidence from clinical and preclinical studies to support a new vaccine registration.
PERISCOPE addresses these issues by developing novel, functional antibody and cellular assays and employing cutting-edge methods to characterize innate immune responses and cell-mediated systemic and mucosal immunity. PERISCOPE combines two major industrial partners with public researchers from academic and public health institutes and small and medium-sized enterprises with expertise in clinical trials, vaccinology, immunology, molecular microbiology, challenge models, and bioinformatics.
Andrew Gorringe, PhD, from Public Health England and the Research and Development Institute at Porton Down, Wiltshire, England, said, “Vaccines have greatly reduced the incidence of pertussis, but it remains the most prevalent ‘vaccine preventable’ disease. This is an exciting period for pertussis vaccine research as we find new ways to understand the immunity that protects from both infection and disease. The PERISCOPE project provides a collaborative environment that combines expertise across Europe to provide a route to the development of new, more effective vaccines.”
GSK and Sanofi Pasteur have cofunded the PERISCOPE Project. Dr. Diavatopoulos made no other financial disclosures.
FROM ESPID 2020
Current PERISCOPE vaccine studies: Toward better pertussis prevention?
With increasing whooping cough numbers, developing an effective new vaccine against Bordetella pertussis is a priority. Results from the multifactorial PERISCOPE Project will help scientists and clinicians move forward.
Dominic Kelly, PhD, talked about vaccine-induced immunity and provided an overview of ongoing clinical trials in the PERISCOPE (Pertussis Correlates of Protection Europe) project in a key research session at the start of the annual meeting of the European Society for Paediatric Infectious Diseases, held virtually this year. Dr. Kelly, a pediatrician at the Children’s Hospital in Oxford and a member of the Oxford Vaccines Group, leads one of the studies in the project looking at infant vaccination.
Dr. Kelly began his presentation by showing a figure depicting where vaccine-induced immunity fits into the larger suite of clinical studies. These studies involve mouse models, human challenge models, and infection patients. A key theme is the use of a core group of immunoassays across all studies, with the hope that they will allow effective cross comparisons.
Dr. Kelly stated, “If we find a correlate of protection in the challenge model, we can then interpret the vaccine studies in the light of that because we are using standardized constant immunoassays.”
The assays being used depend in part on the specific study and the volume of blood available. They will generally include Bordetella-specific antibody and functional antibody assays, as well as interesting studies collecting mucosal samples from infants and adults to look at serological responses. Also under examination are a range of enzyme-linked immune absorbent spot, flow cytometry, and culture techniques looking at Memory B cells, T cells, and gene expression.
Complementing these assay studies, PERISCOPE includes a series of clinical investigations designed to throw light on three areas of interest, described below:
First, researchers hope to gain a better understanding regarding the effects of the original whole cell vaccine versus the current acellular variety. The former uses an inactivated version of the whole organism. Epidemiological studies, animal data, and experience in the field demonstrate that whole-cell vaccination results in a broad, long-lasting, and effective immune response.
By comparison, the acellular pertussis vaccine consists of between three and five protein components, which are purified from cultured Bordetella pertussis. While it is an effective vaccine, its effects are less durable; routine use in some countries is associated with cyclical outbreaks of increasing severity.
A second issue for researchers involved in the PERISCOPE project concerns the effects of maternal immunization. In the United Kingdom in 2012, for example, an increasing number of cases were noted 6-7 years after adoption of an acellular vaccine for routine vaccination in the 2nd-3rd trimester of pregnancy. Vaccination appears to effectively control neonatal disease, but whether this influences infant immune responses and long-term control of pertussis for a population is unknown.
Finally, the group is interested in the effects of an acellular booster across all age groups. While the effects may be short-lived, the booster is a potential strategy for controlling a population by repeated boosting of immunity. This is another area where using novel immunoassays may aid better understanding.
To find answers, the consortium has established four studies: the Gambia Pertussis study (GaPs) in Gambia and AWARE, the sister study to GaPs in the United Kingdom, addressing the acellular pertussis versus cellular pertussis question; the Pertussis Maternal Immunization Study in Finland (MIFI) addressing maternal immunization; and the Booster against Pertussis (BERT) study across three countries (U.K., the Netherlands, and Finland) looking at acellular booster across age groups.
Gambia pertussis study
GaPs is the largest single study in the project and is being run at the Medical Research Council–funded London School of Tropical Medicine center in Gambia. Beate Kampmann, MD, PhD, of Imperial College London, England, is the project lead. It is due to complete in 2022. GaPs seeks to enroll 600 mother/infant pairs and randomize the mothers to either an acellular pertussis booster in pregnancy or a tetanus toxoid control vaccine. Infants are subsequently randomized to an acellular or whole-cell pertussis schedule of primary immunization. The vaccine doses are being given at 2, 3, and 4 months. The primary endpoint is a serological finding being measured at 9 months of age, when the infant would usually receive yellow fever, measles, and rubella vaccination.
GaPs has a number of pathways. Within each of the four arms generated by the two randomizations, the maternal randomization and the infant randomization, there are five subgroups. They are designed to study time points in subgroups A and B after the first dose in more detail, looking at the innate immune responses using gene expression. It will enable researchers to study adaptive immune responses to T cells and B cells after the second dose of vaccine. By employing a range of subgroups, the team can explore the immune profile using the assays referred to above. Such information should provide new insights into the differences between acellular and whole-cell vaccines.
The AWARE study
AWARE is the sister study to GaPs and looks at the acellular/whole pertussis issue. Because many developed countries, such as the United Kingdom, have established maternal immunization programs, it is not possible to randomize mothers. Consequently, researchers have opted to recruit infants of mothers who have received an acellular vaccine in pregnancy and randomize them to either an acellular schedule of primary immunization or a whole-cell schedule.
The selected vaccine is ComVac5 from Bharat Biotech. This whole-cell vaccine differs from that used in Gambia. An early obstacle for AWARE has been seeking permission to import a non-conventional vaccine into Europe. It has delayed the anticipated end date to 2023. Participating infants will receive a two-dose schedule at 2 and 4 months of age per their randomization; then, both groups will go on to receive an acellular pertussis booster at 12 months. At all time points, the team will sample blood for cells and serum, as well as mucosal fluid from the nose. Because the mucosal surface is where the action is, this approach will likely generate new data around antibody responses.
The MIFI
The Pertussis Maternal Immunization Study in Finland is being run by Jussi Mertsola, of the University of Turku, Finland, and Qiushui He, of the National Public Health Institute, Turku. It is due to complete in late 2021. Where, in the United Kingdom, researchers are unable to randomize mothers because of the current guidelines, researchers in Finland do not have a maternal immunization program to consider. MIFI will randomize 80 mothers, 40 to immunization with acellular pertussis and 40 to a control group. Dr. Kelly stated that whole cell vaccines are not available for use in Finland. Participants will receive a two-dose schedule at 3 and 5 months. Blood samples will then be taken to compare the serological and cellular responses, which will help researchers understand the effects of maternal immunization. In addition, there will be sampling of mucosal fluid using a device that collects a standardized aliquot of fluid.
The BERT study
The final clinical element of PERISCOPE presented by Dr. Kelly was the Booster against Pertussis study. This study is near completion. It seeks to examine the use of an acellular booster across different age groups and three countries: the United Kingdom, the Netherlands, and Finland. The study is being coordinated by Guy Berbers, PhD, at the National Institute for Public Health and the Environment in the Netherlands.
BERT comprises four cohorts (A, B, C, D) of different ages: 7-10 years (36 participants), 11-15 years (36 participants), mid-adult (25 participants), and older age (25 participants). After receiving an acellular booster, participants will undergo intense sampling. Sampling will take place immediately after immunization at day 7 and look at adaptive effects, then again at day 28 and day 365.
Because some participants will have already received whole cell or acellular vaccination, this approach will allow researchers to look at the effects of priming (i.e., how long the B cell/T cell antibody responses last).
Involving different countries across Europe ensures wide applicability of results, but also allows researchers to compare the effects of very different immunization histories.
At the end of this ESPID session, Dimitri Diavatopoulos, PhD, assistant professor at the Radboud University Medical Centre Nijmegen, the Netherlands, commented that a future problem in studying pertussis vaccines and their potential clinical application is that most vaccination schedules now involve combination products. Obtaining a stand-alone vaccination may prove difficult, and there may be resistance if it complicates current vaccination programs.
Dr. Kelly acknowledged funding for the PERISCOPE project from GlaxoSmithKline and Pasteur Sanofi.
With increasing whooping cough numbers, developing an effective new vaccine against Bordetella pertussis is a priority. Results from the multifactorial PERISCOPE Project will help scientists and clinicians move forward.
Dominic Kelly, PhD, talked about vaccine-induced immunity and provided an overview of ongoing clinical trials in the PERISCOPE (Pertussis Correlates of Protection Europe) project in a key research session at the start of the annual meeting of the European Society for Paediatric Infectious Diseases, held virtually this year. Dr. Kelly, a pediatrician at the Children’s Hospital in Oxford and a member of the Oxford Vaccines Group, leads one of the studies in the project looking at infant vaccination.
Dr. Kelly began his presentation by showing a figure depicting where vaccine-induced immunity fits into the larger suite of clinical studies. These studies involve mouse models, human challenge models, and infection patients. A key theme is the use of a core group of immunoassays across all studies, with the hope that they will allow effective cross comparisons.
Dr. Kelly stated, “If we find a correlate of protection in the challenge model, we can then interpret the vaccine studies in the light of that because we are using standardized constant immunoassays.”
The assays being used depend in part on the specific study and the volume of blood available. They will generally include Bordetella-specific antibody and functional antibody assays, as well as interesting studies collecting mucosal samples from infants and adults to look at serological responses. Also under examination are a range of enzyme-linked immune absorbent spot, flow cytometry, and culture techniques looking at Memory B cells, T cells, and gene expression.
Complementing these assay studies, PERISCOPE includes a series of clinical investigations designed to throw light on three areas of interest, described below:
First, researchers hope to gain a better understanding regarding the effects of the original whole cell vaccine versus the current acellular variety. The former uses an inactivated version of the whole organism. Epidemiological studies, animal data, and experience in the field demonstrate that whole-cell vaccination results in a broad, long-lasting, and effective immune response.
By comparison, the acellular pertussis vaccine consists of between three and five protein components, which are purified from cultured Bordetella pertussis. While it is an effective vaccine, its effects are less durable; routine use in some countries is associated with cyclical outbreaks of increasing severity.
A second issue for researchers involved in the PERISCOPE project concerns the effects of maternal immunization. In the United Kingdom in 2012, for example, an increasing number of cases were noted 6-7 years after adoption of an acellular vaccine for routine vaccination in the 2nd-3rd trimester of pregnancy. Vaccination appears to effectively control neonatal disease, but whether this influences infant immune responses and long-term control of pertussis for a population is unknown.
Finally, the group is interested in the effects of an acellular booster across all age groups. While the effects may be short-lived, the booster is a potential strategy for controlling a population by repeated boosting of immunity. This is another area where using novel immunoassays may aid better understanding.
To find answers, the consortium has established four studies: the Gambia Pertussis study (GaPs) in Gambia and AWARE, the sister study to GaPs in the United Kingdom, addressing the acellular pertussis versus cellular pertussis question; the Pertussis Maternal Immunization Study in Finland (MIFI) addressing maternal immunization; and the Booster against Pertussis (BERT) study across three countries (U.K., the Netherlands, and Finland) looking at acellular booster across age groups.
Gambia pertussis study
GaPs is the largest single study in the project and is being run at the Medical Research Council–funded London School of Tropical Medicine center in Gambia. Beate Kampmann, MD, PhD, of Imperial College London, England, is the project lead. It is due to complete in 2022. GaPs seeks to enroll 600 mother/infant pairs and randomize the mothers to either an acellular pertussis booster in pregnancy or a tetanus toxoid control vaccine. Infants are subsequently randomized to an acellular or whole-cell pertussis schedule of primary immunization. The vaccine doses are being given at 2, 3, and 4 months. The primary endpoint is a serological finding being measured at 9 months of age, when the infant would usually receive yellow fever, measles, and rubella vaccination.
GaPs has a number of pathways. Within each of the four arms generated by the two randomizations, the maternal randomization and the infant randomization, there are five subgroups. They are designed to study time points in subgroups A and B after the first dose in more detail, looking at the innate immune responses using gene expression. It will enable researchers to study adaptive immune responses to T cells and B cells after the second dose of vaccine. By employing a range of subgroups, the team can explore the immune profile using the assays referred to above. Such information should provide new insights into the differences between acellular and whole-cell vaccines.
The AWARE study
AWARE is the sister study to GaPs and looks at the acellular/whole pertussis issue. Because many developed countries, such as the United Kingdom, have established maternal immunization programs, it is not possible to randomize mothers. Consequently, researchers have opted to recruit infants of mothers who have received an acellular vaccine in pregnancy and randomize them to either an acellular schedule of primary immunization or a whole-cell schedule.
The selected vaccine is ComVac5 from Bharat Biotech. This whole-cell vaccine differs from that used in Gambia. An early obstacle for AWARE has been seeking permission to import a non-conventional vaccine into Europe. It has delayed the anticipated end date to 2023. Participating infants will receive a two-dose schedule at 2 and 4 months of age per their randomization; then, both groups will go on to receive an acellular pertussis booster at 12 months. At all time points, the team will sample blood for cells and serum, as well as mucosal fluid from the nose. Because the mucosal surface is where the action is, this approach will likely generate new data around antibody responses.
The MIFI
The Pertussis Maternal Immunization Study in Finland is being run by Jussi Mertsola, of the University of Turku, Finland, and Qiushui He, of the National Public Health Institute, Turku. It is due to complete in late 2021. Where, in the United Kingdom, researchers are unable to randomize mothers because of the current guidelines, researchers in Finland do not have a maternal immunization program to consider. MIFI will randomize 80 mothers, 40 to immunization with acellular pertussis and 40 to a control group. Dr. Kelly stated that whole cell vaccines are not available for use in Finland. Participants will receive a two-dose schedule at 3 and 5 months. Blood samples will then be taken to compare the serological and cellular responses, which will help researchers understand the effects of maternal immunization. In addition, there will be sampling of mucosal fluid using a device that collects a standardized aliquot of fluid.
The BERT study
The final clinical element of PERISCOPE presented by Dr. Kelly was the Booster against Pertussis study. This study is near completion. It seeks to examine the use of an acellular booster across different age groups and three countries: the United Kingdom, the Netherlands, and Finland. The study is being coordinated by Guy Berbers, PhD, at the National Institute for Public Health and the Environment in the Netherlands.
BERT comprises four cohorts (A, B, C, D) of different ages: 7-10 years (36 participants), 11-15 years (36 participants), mid-adult (25 participants), and older age (25 participants). After receiving an acellular booster, participants will undergo intense sampling. Sampling will take place immediately after immunization at day 7 and look at adaptive effects, then again at day 28 and day 365.
Because some participants will have already received whole cell or acellular vaccination, this approach will allow researchers to look at the effects of priming (i.e., how long the B cell/T cell antibody responses last).
Involving different countries across Europe ensures wide applicability of results, but also allows researchers to compare the effects of very different immunization histories.
At the end of this ESPID session, Dimitri Diavatopoulos, PhD, assistant professor at the Radboud University Medical Centre Nijmegen, the Netherlands, commented that a future problem in studying pertussis vaccines and their potential clinical application is that most vaccination schedules now involve combination products. Obtaining a stand-alone vaccination may prove difficult, and there may be resistance if it complicates current vaccination programs.
Dr. Kelly acknowledged funding for the PERISCOPE project from GlaxoSmithKline and Pasteur Sanofi.
With increasing whooping cough numbers, developing an effective new vaccine against Bordetella pertussis is a priority. Results from the multifactorial PERISCOPE Project will help scientists and clinicians move forward.
Dominic Kelly, PhD, talked about vaccine-induced immunity and provided an overview of ongoing clinical trials in the PERISCOPE (Pertussis Correlates of Protection Europe) project in a key research session at the start of the annual meeting of the European Society for Paediatric Infectious Diseases, held virtually this year. Dr. Kelly, a pediatrician at the Children’s Hospital in Oxford and a member of the Oxford Vaccines Group, leads one of the studies in the project looking at infant vaccination.
Dr. Kelly began his presentation by showing a figure depicting where vaccine-induced immunity fits into the larger suite of clinical studies. These studies involve mouse models, human challenge models, and infection patients. A key theme is the use of a core group of immunoassays across all studies, with the hope that they will allow effective cross comparisons.
Dr. Kelly stated, “If we find a correlate of protection in the challenge model, we can then interpret the vaccine studies in the light of that because we are using standardized constant immunoassays.”
The assays being used depend in part on the specific study and the volume of blood available. They will generally include Bordetella-specific antibody and functional antibody assays, as well as interesting studies collecting mucosal samples from infants and adults to look at serological responses. Also under examination are a range of enzyme-linked immune absorbent spot, flow cytometry, and culture techniques looking at Memory B cells, T cells, and gene expression.
Complementing these assay studies, PERISCOPE includes a series of clinical investigations designed to throw light on three areas of interest, described below:
First, researchers hope to gain a better understanding regarding the effects of the original whole cell vaccine versus the current acellular variety. The former uses an inactivated version of the whole organism. Epidemiological studies, animal data, and experience in the field demonstrate that whole-cell vaccination results in a broad, long-lasting, and effective immune response.
By comparison, the acellular pertussis vaccine consists of between three and five protein components, which are purified from cultured Bordetella pertussis. While it is an effective vaccine, its effects are less durable; routine use in some countries is associated with cyclical outbreaks of increasing severity.
A second issue for researchers involved in the PERISCOPE project concerns the effects of maternal immunization. In the United Kingdom in 2012, for example, an increasing number of cases were noted 6-7 years after adoption of an acellular vaccine for routine vaccination in the 2nd-3rd trimester of pregnancy. Vaccination appears to effectively control neonatal disease, but whether this influences infant immune responses and long-term control of pertussis for a population is unknown.
Finally, the group is interested in the effects of an acellular booster across all age groups. While the effects may be short-lived, the booster is a potential strategy for controlling a population by repeated boosting of immunity. This is another area where using novel immunoassays may aid better understanding.
To find answers, the consortium has established four studies: the Gambia Pertussis study (GaPs) in Gambia and AWARE, the sister study to GaPs in the United Kingdom, addressing the acellular pertussis versus cellular pertussis question; the Pertussis Maternal Immunization Study in Finland (MIFI) addressing maternal immunization; and the Booster against Pertussis (BERT) study across three countries (U.K., the Netherlands, and Finland) looking at acellular booster across age groups.
Gambia pertussis study
GaPs is the largest single study in the project and is being run at the Medical Research Council–funded London School of Tropical Medicine center in Gambia. Beate Kampmann, MD, PhD, of Imperial College London, England, is the project lead. It is due to complete in 2022. GaPs seeks to enroll 600 mother/infant pairs and randomize the mothers to either an acellular pertussis booster in pregnancy or a tetanus toxoid control vaccine. Infants are subsequently randomized to an acellular or whole-cell pertussis schedule of primary immunization. The vaccine doses are being given at 2, 3, and 4 months. The primary endpoint is a serological finding being measured at 9 months of age, when the infant would usually receive yellow fever, measles, and rubella vaccination.
GaPs has a number of pathways. Within each of the four arms generated by the two randomizations, the maternal randomization and the infant randomization, there are five subgroups. They are designed to study time points in subgroups A and B after the first dose in more detail, looking at the innate immune responses using gene expression. It will enable researchers to study adaptive immune responses to T cells and B cells after the second dose of vaccine. By employing a range of subgroups, the team can explore the immune profile using the assays referred to above. Such information should provide new insights into the differences between acellular and whole-cell vaccines.
The AWARE study
AWARE is the sister study to GaPs and looks at the acellular/whole pertussis issue. Because many developed countries, such as the United Kingdom, have established maternal immunization programs, it is not possible to randomize mothers. Consequently, researchers have opted to recruit infants of mothers who have received an acellular vaccine in pregnancy and randomize them to either an acellular schedule of primary immunization or a whole-cell schedule.
The selected vaccine is ComVac5 from Bharat Biotech. This whole-cell vaccine differs from that used in Gambia. An early obstacle for AWARE has been seeking permission to import a non-conventional vaccine into Europe. It has delayed the anticipated end date to 2023. Participating infants will receive a two-dose schedule at 2 and 4 months of age per their randomization; then, both groups will go on to receive an acellular pertussis booster at 12 months. At all time points, the team will sample blood for cells and serum, as well as mucosal fluid from the nose. Because the mucosal surface is where the action is, this approach will likely generate new data around antibody responses.
The MIFI
The Pertussis Maternal Immunization Study in Finland is being run by Jussi Mertsola, of the University of Turku, Finland, and Qiushui He, of the National Public Health Institute, Turku. It is due to complete in late 2021. Where, in the United Kingdom, researchers are unable to randomize mothers because of the current guidelines, researchers in Finland do not have a maternal immunization program to consider. MIFI will randomize 80 mothers, 40 to immunization with acellular pertussis and 40 to a control group. Dr. Kelly stated that whole cell vaccines are not available for use in Finland. Participants will receive a two-dose schedule at 3 and 5 months. Blood samples will then be taken to compare the serological and cellular responses, which will help researchers understand the effects of maternal immunization. In addition, there will be sampling of mucosal fluid using a device that collects a standardized aliquot of fluid.
The BERT study
The final clinical element of PERISCOPE presented by Dr. Kelly was the Booster against Pertussis study. This study is near completion. It seeks to examine the use of an acellular booster across different age groups and three countries: the United Kingdom, the Netherlands, and Finland. The study is being coordinated by Guy Berbers, PhD, at the National Institute for Public Health and the Environment in the Netherlands.
BERT comprises four cohorts (A, B, C, D) of different ages: 7-10 years (36 participants), 11-15 years (36 participants), mid-adult (25 participants), and older age (25 participants). After receiving an acellular booster, participants will undergo intense sampling. Sampling will take place immediately after immunization at day 7 and look at adaptive effects, then again at day 28 and day 365.
Because some participants will have already received whole cell or acellular vaccination, this approach will allow researchers to look at the effects of priming (i.e., how long the B cell/T cell antibody responses last).
Involving different countries across Europe ensures wide applicability of results, but also allows researchers to compare the effects of very different immunization histories.
At the end of this ESPID session, Dimitri Diavatopoulos, PhD, assistant professor at the Radboud University Medical Centre Nijmegen, the Netherlands, commented that a future problem in studying pertussis vaccines and their potential clinical application is that most vaccination schedules now involve combination products. Obtaining a stand-alone vaccination may prove difficult, and there may be resistance if it complicates current vaccination programs.
Dr. Kelly acknowledged funding for the PERISCOPE project from GlaxoSmithKline and Pasteur Sanofi.
FROM ESPID 2020
New tool may provide point-of-care differentiation between bacterial, viral infections
The World Health Organization estimates that 14.9 million of 57 million annual deaths worldwide (25%) are related directly to diseases caused by bacterial and/or viral infections.
The first crucial step in order to build a successful surveillance system is to accurately identify and diagnose disease, Ivana Pennisi reminded the audience at the annual meeting of the European Society for Paediatric Infectious Diseases, held virtually this year. A problem, particularly in primary care, is differentiating between patients with bacterial infections who might benefit from antibiotics and those with viral infections where supportive treatment is generally required. One solution might a rapid point-of-care tool.
Ms. Pennisi described early experiences of using microchip technology to detect RNA biomarkers in the blood rather than look for the pathogen itself. Early results suggest high diagnostic accuracy at low cost.
It is known that when a bacteria or virus enters the body, it stimulates the immune system in a unique way leading to the expression of different genes in the host blood. As part of the Personalized Management of Febrile Illnesses study, researchers have demonstrated a number of high correlated transcripts. Of current interest are two genes which are upregulated in childhood febrile illnesses.
Ms. Pennisi, a PhD student working as part of a multidisciplinary at the department of infectious disease and Centre for Bioinspired Technology at Imperial College, London, developed loop-mediated isothermal amplification (LAMP) assays to detect for the first time host RNA signatures on a nucleic acid–based point-of-care handheld system to discriminate bacterial from viral infection. The amplification reaction is then combined with microchip technology in the well of a portable point-of-care device named Lacewing. It translates the nucleic acid amplification signal into a quantitative electrochemical signal without the need for a thermal cycler.
The combination of genomic expertise in the section of paediatrics lead by Michael Levin, PhD, and microchip-based technologies in the department of electrical and electronic engineering under the guidance of Pantelis Georgiou, PhD, enabled the team overcome many clinical challenges.
Ms. Pennisi presented her team’s early experiences with clinical samples from 455 febrile children. First, transcription isothermal amplification techniques were employed to confirm bacterial and viral infections. Results were then validated using standard fluorescent-based quantitative polymerase chain reaction (PCR) instruments. In order to define a decision boundary between bacterial and viral patients, cutoff levels were determined using multivariate logistic regression analysis. Results then were evaluated using microarrays, reverse transcriptase PCR (RT-PCR), and the eLAMP to confirm comparability with preferred techniques.
In conclusion, Ms. Pennisi reported that the two-gene signature combined with the use of eLAMP technology in She outlined her vision for the future: “The patient sample and reagent are loaded into a disposable cartridge. This is then placed into a device to monitor in real time the reaction and share all the data via a Bluetooth to a dedicated app on a smart phone. All data and location of the outbreak are then stored in [the] cloud, making it easier for epidemiological studies and tracking of new outbreaks. We hope that by enhancing the capability of our platform, we contribute to better patient care.”
“Distinguishing between bacterial and viral infections remains one of the key questions in the daily pediatric acute care,” commented Lauri Ivaska, MD, from the department of pediatrics and adolescent medicine at Turku (Finland) University Hospital. “One of the most promising laboratory methods to do this is by measuring quantities of two specific host RNA transcripts from a blood sample. It would be of great importance if this could be done reliably by using a fast and cheap method as presented here by Ivana Pennisi.”
Ms. Pennisi had no relevant financial disclosures.
The World Health Organization estimates that 14.9 million of 57 million annual deaths worldwide (25%) are related directly to diseases caused by bacterial and/or viral infections.
The first crucial step in order to build a successful surveillance system is to accurately identify and diagnose disease, Ivana Pennisi reminded the audience at the annual meeting of the European Society for Paediatric Infectious Diseases, held virtually this year. A problem, particularly in primary care, is differentiating between patients with bacterial infections who might benefit from antibiotics and those with viral infections where supportive treatment is generally required. One solution might a rapid point-of-care tool.
Ms. Pennisi described early experiences of using microchip technology to detect RNA biomarkers in the blood rather than look for the pathogen itself. Early results suggest high diagnostic accuracy at low cost.
It is known that when a bacteria or virus enters the body, it stimulates the immune system in a unique way leading to the expression of different genes in the host blood. As part of the Personalized Management of Febrile Illnesses study, researchers have demonstrated a number of high correlated transcripts. Of current interest are two genes which are upregulated in childhood febrile illnesses.
Ms. Pennisi, a PhD student working as part of a multidisciplinary at the department of infectious disease and Centre for Bioinspired Technology at Imperial College, London, developed loop-mediated isothermal amplification (LAMP) assays to detect for the first time host RNA signatures on a nucleic acid–based point-of-care handheld system to discriminate bacterial from viral infection. The amplification reaction is then combined with microchip technology in the well of a portable point-of-care device named Lacewing. It translates the nucleic acid amplification signal into a quantitative electrochemical signal without the need for a thermal cycler.
The combination of genomic expertise in the section of paediatrics lead by Michael Levin, PhD, and microchip-based technologies in the department of electrical and electronic engineering under the guidance of Pantelis Georgiou, PhD, enabled the team overcome many clinical challenges.
Ms. Pennisi presented her team’s early experiences with clinical samples from 455 febrile children. First, transcription isothermal amplification techniques were employed to confirm bacterial and viral infections. Results were then validated using standard fluorescent-based quantitative polymerase chain reaction (PCR) instruments. In order to define a decision boundary between bacterial and viral patients, cutoff levels were determined using multivariate logistic regression analysis. Results then were evaluated using microarrays, reverse transcriptase PCR (RT-PCR), and the eLAMP to confirm comparability with preferred techniques.
In conclusion, Ms. Pennisi reported that the two-gene signature combined with the use of eLAMP technology in She outlined her vision for the future: “The patient sample and reagent are loaded into a disposable cartridge. This is then placed into a device to monitor in real time the reaction and share all the data via a Bluetooth to a dedicated app on a smart phone. All data and location of the outbreak are then stored in [the] cloud, making it easier for epidemiological studies and tracking of new outbreaks. We hope that by enhancing the capability of our platform, we contribute to better patient care.”
“Distinguishing between bacterial and viral infections remains one of the key questions in the daily pediatric acute care,” commented Lauri Ivaska, MD, from the department of pediatrics and adolescent medicine at Turku (Finland) University Hospital. “One of the most promising laboratory methods to do this is by measuring quantities of two specific host RNA transcripts from a blood sample. It would be of great importance if this could be done reliably by using a fast and cheap method as presented here by Ivana Pennisi.”
Ms. Pennisi had no relevant financial disclosures.
The World Health Organization estimates that 14.9 million of 57 million annual deaths worldwide (25%) are related directly to diseases caused by bacterial and/or viral infections.
The first crucial step in order to build a successful surveillance system is to accurately identify and diagnose disease, Ivana Pennisi reminded the audience at the annual meeting of the European Society for Paediatric Infectious Diseases, held virtually this year. A problem, particularly in primary care, is differentiating between patients with bacterial infections who might benefit from antibiotics and those with viral infections where supportive treatment is generally required. One solution might a rapid point-of-care tool.
Ms. Pennisi described early experiences of using microchip technology to detect RNA biomarkers in the blood rather than look for the pathogen itself. Early results suggest high diagnostic accuracy at low cost.
It is known that when a bacteria or virus enters the body, it stimulates the immune system in a unique way leading to the expression of different genes in the host blood. As part of the Personalized Management of Febrile Illnesses study, researchers have demonstrated a number of high correlated transcripts. Of current interest are two genes which are upregulated in childhood febrile illnesses.
Ms. Pennisi, a PhD student working as part of a multidisciplinary at the department of infectious disease and Centre for Bioinspired Technology at Imperial College, London, developed loop-mediated isothermal amplification (LAMP) assays to detect for the first time host RNA signatures on a nucleic acid–based point-of-care handheld system to discriminate bacterial from viral infection. The amplification reaction is then combined with microchip technology in the well of a portable point-of-care device named Lacewing. It translates the nucleic acid amplification signal into a quantitative electrochemical signal without the need for a thermal cycler.
The combination of genomic expertise in the section of paediatrics lead by Michael Levin, PhD, and microchip-based technologies in the department of electrical and electronic engineering under the guidance of Pantelis Georgiou, PhD, enabled the team overcome many clinical challenges.
Ms. Pennisi presented her team’s early experiences with clinical samples from 455 febrile children. First, transcription isothermal amplification techniques were employed to confirm bacterial and viral infections. Results were then validated using standard fluorescent-based quantitative polymerase chain reaction (PCR) instruments. In order to define a decision boundary between bacterial and viral patients, cutoff levels were determined using multivariate logistic regression analysis. Results then were evaluated using microarrays, reverse transcriptase PCR (RT-PCR), and the eLAMP to confirm comparability with preferred techniques.
In conclusion, Ms. Pennisi reported that the two-gene signature combined with the use of eLAMP technology in She outlined her vision for the future: “The patient sample and reagent are loaded into a disposable cartridge. This is then placed into a device to monitor in real time the reaction and share all the data via a Bluetooth to a dedicated app on a smart phone. All data and location of the outbreak are then stored in [the] cloud, making it easier for epidemiological studies and tracking of new outbreaks. We hope that by enhancing the capability of our platform, we contribute to better patient care.”
“Distinguishing between bacterial and viral infections remains one of the key questions in the daily pediatric acute care,” commented Lauri Ivaska, MD, from the department of pediatrics and adolescent medicine at Turku (Finland) University Hospital. “One of the most promising laboratory methods to do this is by measuring quantities of two specific host RNA transcripts from a blood sample. It would be of great importance if this could be done reliably by using a fast and cheap method as presented here by Ivana Pennisi.”
Ms. Pennisi had no relevant financial disclosures.
FROM ESPID 2020