BEATRIX (group B strEptococcus mATeRnal and Infant VaX study) The purpose of this study is to learn about the safety and how the group B streptococcus (GBS) vaccine works in pregnant women and their babies. This study is seeking healthy pregnant participants: * aged 49 or younger who can join. * between 24 and 36 weeks of gestation ("Gestational age" is a medical term used to describe how far along your pregnancy is) * had a fetal ultrasound examination performed with no major fetal abnormalities observed * documented negative for HIV, syphilis and Hepatitis B All participants in this study will receive only 1 shot in an arm. This could either be a group B streptococcus 6-valent polysaccharide conjugate vaccine (GBS6) or placebo. Placebo is an inactive substance used in the study for comparison purposes; in this study, the placebo injection will be saline (saltwater). The pregnant participants may take part in this study for a maximum of 14 months (6 months after delivery) , and their babies for about 12 months after they are born. The pregnant participants will need to visit the research site at least 3 to 4 times with some visits permitted to occur over the telephone. A subset of infants will be asked to take part in the study for up to 19 months. The subset will receive diphtheria toxoid-containing vaccine and/or pneumococcal vaccine following each country's standard immunization plan and have blood drawn 1 month after completion of the primary and/or toddler (booster) doses.
Age range
1 Day – 49 Years
Sex
ALL
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The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
The proportion of maternal participants reporting prespecified local reactions within 7 days following study intervention
Timeframe: Within 7 days
The proportion of maternal participants reporting prespecified systemic events within 7 days following study intervention
Timeframe: Within 7 days
The proportion of maternal participants reporting adverse events (AEs) through 1 month following study intervention
Timeframe: 1 month
The proportion of maternal participants reporting serious adverse events (SAEs) through 6 months after delivery
Timeframe: 6 months after delivery
The proportion of maternal participants reporting medically attended adverse events (MAAEs) through 6 months after delivery
Timeframe: 6 months after delivery
The proportion of maternal participants reporting adverse events of special interest (AESIs) through 6 months after delivery.
Timeframe: 6 months after delivery
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The proportion of infant participants born to pregnant women who were vaccinated with GBS6 during pregnancy reporting adverse events (AEs) from birth through 1 month of age
Timeframe: Birth to 1 month of age
The proportion of infant participants born to pregnant women who were vaccinated with GBS6 during pregnancy reporting serious adverse events (SAEs) from birth through end of the study
Timeframe: Through study completion, at least 1 year
The proportion of infant participants born to pregnant women who were vaccinated with GBS6 during pregnancy reporting medically attended adverse events (MAAEs) from birth through 6 months of age
Timeframe: Birth to 6 months of age
The proportion of infant participants born to pregnant women who were vaccinated with GBS6 during pregnancy reporting adverse events of special interest (AESIs) from birth through end of study
Timeframe: Through study completion, at least 1 year
To measure the relative risk reduction in the proportion of infant participants at birth with GBS serotype-specific IgG antibody concentrations below predefined serotype-specific GBS late onset disease thresholds in the GBS6 group to the placebo group
Timeframe: Birth
To measure the relative risk reduction in the proportion of infant participants at birth with GBS serotype-specific IgG antibody concentrations below predefined serotype-specific GBS early onset disease thresholds in the GBS6 group to the placebo group
Timeframe: Birth
To evaluate the aggregate predicted VE combining all 6 serotypes in GBS6 to provide protection from invasive GBS late onset disease based on serotype specific anti-CPS IgG concentrations measured in infants at birth.
Timeframe: Birth
To evaluate the aggregate predicted VE combining all 6 serotypes in GBS6 to provide protection from invasive GBS early onset disease based on serotype specific anti-CPS IgG concentrations measured in infants at birth.
Timeframe: Birth