NCT07160244

BEATRIX: A Study to Learn About a Group B Streptococcus Vaccine in Healthy Pregnant Women and Their Babies

A Phase 3, Randomized, Placebo-Controlled, Double-Blinded Trial to Evaluate the Safety, Tolerability, and Immunogenicity of a Multivalent Group B Streptococcus Vaccine in Healthy Pregnant Women and Their Infants

• Status: Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 6,000 (estimated)
• Sponsor: Pfizer · Industry
• Sex: All
• Age: 1 Day – 49 Years
• Healthy volunteers: Accepted

Summary

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.

Conditions

• Healthy

Interventions

Type	Name	Description
BIOLOGICAL	Multivalent Group B streptococcus vaccine	Multivalent Group B streptococcus vaccine
BIOLOGICAL	Placebo	Saline Control
BIOLOGICAL	Infanrix hexa	Vaccine administered in a subset of infant participants as per the national immunization schedule
BIOLOGICAL	Prevenar 20	Vaccine administered in a subset of infant participants as per the national immunization schedule
BIOLOGICAL	Pediarix	Vaccine administered in a subset of infant participants as per the national immunization schedule
BIOLOGICAL	Prevnar 20	Vaccine administered in a subset of infant participants as per the national immunization schedule
BIOLOGICAL	Infanrix	Vaccine administered in a subset of infant participants as per the national immunization schedule

Timeline

• Start date: 2025-08-25
• Primary completion: 2028-11-06
• Completion: 2029-03-02
• First posted: 2025-09-08
• Last updated: 2026-04-13

Locations

158 sites across 13 countries: United States, Argentina, Brazil, Canada, Finland, Japan, Mexico, Netherlands, South Africa, South Korea, Spain, Taiwan, United Kingdom

Regulatory

• FDA-regulated drug study