Brief Title
Sources of COmplement in Meningococcal and Pertussis Serum Bactericidal Antibody Assays
Official Title
Sources of COmplement in Meningococcal and Pertussis Serum Bactericidal Antibody Assays
Brief Summary
This study is designed to allow cord blood sample collection from the cords of babies born in
three gestational age windows: ≥37 gestational weeks, 32-36+6 gestational weeks and less than
32 gestational weeks to investigate whether the result obtained using a standard hSBA assay
is comparable to that achieved using complement from a gestation matched population for
meningococcal B and pertussis.
Detailed Description
Newborn infants, particularly those who are born preterm, are vulnerable to infection because
of their immature immune systems. Invasive meningococcal disease (IMD) and pertussis both
represent significant risks to the newborn infant.
Invasive meningococcal disease (IMD), caused by Neisseria meningitidis, is a devastating
illness with a case fatality rate of 10-20% even with intensive treatment. Even infants who
survive IMD experience significant disability in 10-20% of cases. Serogroups A, B, C, Y, W
and X cause almost all cases of IMD, and in Europe, North America and parts of Latin America
serogroup B is responsible for the majority of cases. In the UK there were 747 cases of IMD
in 2016/17 and Men B was responsible for 396 (53%) of these. The major burden of disease is
in infants under the age of 1 year. Pertussis is a highly infectious respiratory illness
caused by Bordetella pertussis which can cause significant morbidity and mortality in young
infants. There has been an increase in the incidence of pertussis in the UK, along with other
high income countries in recent years which has disproportionately affected young infants.
Infants in the UK are vaccinated against meningococcal group B disease at 2, 4 and 12 months
with Bexsero® and against pertussis at 2,3 and 4 months as part of the 6-in-1 vaccine
Infanrix hexa®. Additionally, since 2012 pregnant women in the UK have been routinely offered
pertussis vaccination during pregnancy to protect the infant in the first few months of life
prior to them receiving their own vaccinations.
Serum bactericidal antibody (SBA) assays are important in the assessment of immunity
following vaccination and are used in the production, release and licensure of some vaccines
and the evaluation of the function of others. SBA assays for pertussis and meningococcal B
typically use adult complement from a healthy adult donor pool. There is some concern that
using adult complement may not allow an adequate assessment of neonatal immunity. The
concentration of most complement components in the neonate is around 10-80% of that in the
adult and circulating regulator levels are also reduced. Differences in complement function
are more pronounced in preterm infants and the differences in the quality and activation of
complement in neonates raises questions about whether an SBA assay using adult complement
sources allows an accurate assessment of neonatal immunity.
In this study the investigators will create a pooled complement source for three different
gestational ages, ≥37 gestational weeks, 32-36+6 gestational weeks and less than 32
gestational weeks, which will allow the investigators to compare the results of the pertussis
and meningococcal SBA assays when using both standard adult complement and a gestational age
appropriate complement source. To do this the investigators will collect cord blood samples
from deliveries within the three gestational age groups.
Study Type
Observational
Primary Outcome
SBA assay results
Condition
Pertussis
Intervention
Cord blood sampling
Study Arms / Comparison Groups
Term babies
Description: Babies who are born at or after 37 gestational weeks.
Publications
* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.
Recruitment Information
Recruitment Status
Procedure
Estimated Enrollment
45
Start Date
October 28, 2020
Completion Date
September 21, 2021
Primary Completion Date
September 21, 2021
Eligibility Criteria
Inclusion Criteria:
- Pregnant and planning to deliver at St George's University Hospitals NHS Foundation
Trust
Exclusion Criteria:
- Aged less than 16 years
- Known complement deficiency
Gender
Female
Ages
16 Years - N/A
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Contacts
Anna Calvert, MBChB, 02087253887, [email protected]
Location Countries
United Kingdom
Location Countries
United Kingdom
Administrative Informations
NCT ID
NCT04023929
Organization ID
2019.0116
Responsible Party
Sponsor
Study Sponsor
St George's, University of London
Study Sponsor
Anna Calvert, MBChB, Principal Investigator, St George's, Univeristy of London
Verification Date
January 2021