Pertussis vaccines have been very successful in reducing the global burden of pertussis-related disease. However, in the last decade there has been a rise in pertussis incidence, particularly in vaccinated adolescents and adults in industrialized countries. The increased circulation of B. pertussis (Bp) constitutes a risk for transmission to vulnerable infants and older adults. Additionally, immunity in humans has been shown to wane rapidly after immunization with pertussis vaccines, especially with acellular pertussis (aP) vaccines, suggesting that the improved reactogenicity profile of aP compared to whole cell pertussis vaccines, may be accompanied by differences in duration of immunity.
Why do we need PERISCOPE?
- Pertussis remains a leading cause of infant mortality in non-industrialized countries.
- The incidence of pertussis is increasing in different age groups despite high coverage by aP vaccines
- The number of infections with aP-antigen deficient strains is increasing
- wP and aP vaccines show different profiles in terms of immunogenicity, reactogenicity and duration of immunity. The immune mechanisms underlying persistent protection are not well understood.
- Maternal immunization offers effective protection to vulnerable infants. However, questions remain regarding the duration of protection and potential impact on the primary infant vaccination schedule.
What are the objectives of PERISCOPE?
- Accelerating the development of improved vaccines against Bp and/or vaccination strategies that will be used to control B. pertussis in humans.
- Fostering scientific innovation and rebuild the ecosystem and technical infrastructure needed in Europe to evaluate novel pertussis vaccine candidates.
- Improving the understanding of the pathogenesis of B. pertussis infection and its potential impact on the recently observed changes in pertussis epidemiology
- Identifying biomarkers of long lasting protective immunity to pertussis in humans
- Investigating the impact of maternal vaccination on the infant response to pertussis vaccination
What are the key challenges to develop new vaccines?
- Registration for new infant vaccines based on efficacy studies is challenging in view of the high DTaP coverage and effectiveness in the first years of life
- An extended toolbox of bioassays to measure the human immune response is needed
- Biomarkers to predict long lasting immunity are not yet known
- Correlates of protection in humans have not yet been identified
- New models to assess vaccine efficacy and shorten the development process of new vaccines are needed
- Discussion with regulatory authorities is warranted to advance the field