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
2 other identifiers
interventional
6,000
13 countries
165
Brief 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.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_3 healthy
Started Aug 2025
Longer than P75 for phase_3 healthy
165 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
August 14, 2025
CompletedStudy Start
First participant enrolled
August 25, 2025
CompletedFirst Posted
Study publicly available on registry
September 8, 2025
CompletedPrimary Completion
Last participant's last visit for primary outcome
November 6, 2028
ExpectedStudy Completion
Last participant's last visit for all outcomes
March 2, 2029
May 5, 2026
May 1, 2026
3.2 years
August 14, 2025
May 4, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (12)
The proportion of maternal participants reporting prespecified local reactions within 7 days following study intervention
Within 7 days
The proportion of maternal participants reporting prespecified systemic events within 7 days following study intervention
Within 7 days
The proportion of maternal participants reporting adverse events (AEs) through 1 month following study intervention
1 month
The proportion of maternal participants reporting serious adverse events (SAEs) through 6 months after delivery
6 months after delivery
The proportion of maternal participants reporting medically attended adverse events (MAAEs) through 6 months after delivery
6 months after delivery
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
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
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 events (MAAEs) from birth through 6 months of age
Birth to 6 months of age
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
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
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.
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.
Birth
Secondary Outcomes (6)
To measure GBS serotype-specific opsonophagocytic titers in infant participants at birth by geometric mean ratio between GBS6 group versus placebo group and by the difference in seroresponse rates between GBS6 group and placebo group
Birth
To describe anti-CPS IgG antibody levels predicted to provide protection from invasive GBS disease (all disease) caused by the 6 individual vaccine serotypes in infants when GBS6 is administered to healthy pregnant women.
Birth
To describe anti-CPS IgG antibody levels in infant participants born to maternal participants vaccinated with GBS6.
Birth
To describe anti-CPS IgG antibody levels predicted to provide protection from invasive GBS LOD and EOD, separately, caused by the 6 individual vaccine serotypes (Ia, Ib, II, III, IV, and V) in infants when GBS6 is administered to healthy pregnant women.
Birth
To measure GBS serotype-specific IgG by geometric mean concentration in maternal participants at 1 month after vaccination and at delivery.
1 month after vaccination and at delivery
- +1 more secondary outcomes
Study Arms (7)
GBS6
EXPERIMENTALMultivalent group B streptococcus vaccine
Placebo
PLACEBO COMPARATORPlacebo
Infanrix hexa
EXPERIMENTALCommercially available combination vaccine containing diphtheria, tetanus, pertussis (whooping cough), hepatitis B, poliomyelitis (polio), and Haemophilus influenzae type b (Hib)
Prevenar 20
EXPERIMENTALCommercially available vaccine that protects against 20 strains of Streptococcus pneumoniae
Pediarix
EXPERIMENTALCommercially available combination vaccine containing diphtheria, tetanus, pertussis (whooping cough), hepatitis B, and polio
Prevnar 20
EXPERIMENTALCommercially available vaccine that protects against 20 strains of Streptococcus pneumoniae
Infanrix
EXPERIMENTALCommercially available combination vaccine containing diphtheria, tetanus, and pertussis
Interventions
Vaccine administered in a subset of infant participants as per the national immunization schedule
Vaccine administered in a subset of infant participants as per the national immunization schedule
Multivalent Group B streptococcus vaccine
Vaccine administered in a subset of infant participants as per the national immunization schedule
Vaccine administered in a subset of infant participants as per the national immunization schedule
Vaccine administered in a subset of infant participants as per the national immunization schedule
Eligibility Criteria
You may qualify if:
- Healthy pregnant women ≤49 years of age who are between 24 0/7 and 36 0/7 weeks of gestation on the day of planned vaccination, with an uncomplicated, singleton pregnancy, and who have no known increased risk of complications.
- Had a fetal anomaly ultrasound examination with no significant fetal abnormalities observed.
- Documented negative human immunodeficiency virus (HIV) antibody test, syphilis test, and hepatitis B virus (HBV) surface antigen test during this pregnancy and prior to randomization.
- Capable of giving personal signed informed consent.
- Willing to give informed consent for her infant to participate in the study.
You may not qualify if:
- Prepregnancy body mass index (BMI) of \>40 kg/m2.
- Current pregnancy complications or abnormalities that may increase the risk associated with the participation in and completion of the study.
- Prior pregnancy complications or abnormalities that, based on the investigator's judgment, may increase the risk associated with the participation in and completion of the study.
- History of microbiologically proven invasive disease caused by GBS in the current pregnancy.
- A known or suspected infection during the current pregnancy that may increase the risk of complications in pregnancy (eg, active tuberculosis, syphilis, primary genital herpes simplex, malaria).
- \- Evidence of a signed and dated ICD signed by the parent(s)/legally authorized representative or legal guardian
- \- Children or grandchildren who are direct descendants of investigator site staff or sponsor and sponsor delegate employees directly involved in the conduct of the study.
- \- Children with a known or suspected contraindication to any vaccine administered in the infant vaccine immunogenicity subset.
- Refer to the study contact for further eligibility details
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Pfizerlead
Study Sites (165)
Center for Research in Women's Health
Birmingham, Alabama, 35233, United States
Children's of Alabama
Birmingham, Alabama, 35233, United States
University of Alabama at Birmingham - School of Medicine
Birmingham, Alabama, 35233, United States
University of Alabama at Birmingham Women & Infants Center
Birmingham, Alabama, 35294, United States
SEC Clinical Research
Dothan, Alabama, 36305, United States
ClinMed
Phoenix, Arizona, 85004, United States
Valleywise Comprehensive Health Center Women's Clinic
Phoenix, Arizona, 85008, United States
Valleywise Health Medical Center
Phoenix, Arizona, 85008, United States
Genesis OB/GYN
Tucson, Arizona, 85741, United States
Eclipse Clinical Research
Tucson, Arizona, 85745, United States
Antelope Valley Medical Center
Lancaster, California, 93534, United States
Chemidox Clinical Trials
Lancaster, California, 93534, United States
Lucile Packard Children's Hospital
Palo Alto, California, 94304, United States
Stanford Obstetrics Clinic
Palo Alto, California, 94304, United States
Stanford University Medical Center
Palo Alto, California, 94304, United States
Stanford University
Palo Alto, California, 94304, United States
South Florida Clinical Research Institute - Margate
Margate, Florida, 33063, United States
Citadelle Clinical Research
North Miami Beach, Florida, 33162, United States
Emerald Coast OBGYN Clinical Research
Panama City, Florida, 32405, United States
HCA Florida Gulf Coast Hospital
Panama City, Florida, 32405, United States
Advanced Specialty Research
Boise, Idaho, 83702, United States
Express Lab
Garden City, Idaho, 83714, United States
Clinical Research Prime
Idaho Falls, Idaho, 83404, United States
Eastern Idaho Regional Medical Center
Idaho Falls, Idaho, 83404, United States
Mountain View Hospital
Idaho Falls, Idaho, 83404, United States
Madison Memorial Hospital
Rexburg, Idaho, 83440, United States
Accellacare - McFarland
Ames, Iowa, 50010, United States
Mary Greeley Medical Center
Ames, Iowa, 50010, United States
McFarland Clinic, PC
Ames, Iowa, 50010, United States
Velocity Clinical Research, Covington
Covington, Louisiana, 70433, United States
Center for Immunization Research
Baltimore, Maryland, 21205, United States
Center for Immunization Research
Baltimore, Maryland, 21224, United States
Johns Hopkins Bayview Medical Center
Baltimore, Maryland, 21224, United States
Gynecology and Obstetrics at Johns Hopkins Health Care and Surgery Center- White Marsh
Nottingham, Maryland, 21236, United States
Boston Medical Center
Boston, Massachusetts, 02118, United States
Washington University School of Medicine
St Louis, Missouri, 63110, United States
Boeson Research GTF
Great Falls, Montana, 59405, United States
Origin Health GTF
Great Falls, Montana, 59405, United States
Boeson Research MSO
Missoula, Montana, 59804, United States
Origin Health
Missoula, Montana, 59804, United States
Velocity Clinical Research, Grand Island
Grand Island, Nebraska, 68803, United States
Midwest Children's Health Research Center
Lincoln, Nebraska, 68504, United States
Midwest Children's Health Research Center
Lincoln, Nebraska, 68505, United States
Bryan Health
Lincoln, Nebraska, 68506, United States
Midwest Children's Health Research Institute
Lincoln, Nebraska, 68516, United States
Women's Health Care Center of Williamsburg
Lincoln, Nebraska, 68516, United States
Midwest Children's Health Research Center
Lincoln, Nebraska, 68522, United States
Velocity Clinical Research, Norfolk
Norfolk, Nebraska, 68701, United States
Stony Brook Medicine Clinical Research Center
East Setauket, New York, 11733, United States
ACGC Research, NYU Ambulatory Care Garden City
Garden City, New York, 11530, United States
NYU Langone Ambulatory Care Garden City
Garden City, New York, 11530, United States
NYU Langone Long Island, Clinical Research Center 3-002 (Admin only)
Mineola, New York, 11501, United States
Weill Cornell Medicine - New York Presbyterian Hospital
New York, New York, 10065, United States
Stony Brook University
Stony Brook, New York, 11794, United States
Duke Vaccine and Trials Unit
Durham, North Carolina, 27703, United States
Duke University - Main Hospital and Clinics
Durham, North Carolina, 27705, United States
Duke University - Main Hospital and Clinics
Durham, North Carolina, 27710, United States
Cincinnati Children's Hospital Medical Center
Cincinnati, Ohio, 45206, United States
University of Cincinnati Physicians Midtown
Cincinnati, Ohio, 45213, United States
Hoxworth Center
Cincinnati, Ohio, 45219, United States
University of Cincinnati Medical Center
Cincinnati, Ohio, 45219, United States
Cincinnati Children's Hospital Medical Center
Cincinnati, Ohio, 45229, United States
University Hospitals
Cleveland, Ohio, 44106, United States
Cincinnati Children's Hospital Medical Center Liberty
Liberty Township, Ohio, 45044, United States
Cincinnati Children's Hospital Medical Center Mason
Mason, Ohio, 45040, United States
Senders Pediatrics
South Euclid, Ohio, 44121, United States
University of Cincinnati Medical Center West Chester
West Chester, Ohio, 45069, United States
University of Cincinnati Physicians
West Chester, Ohio, 45069, United States
UPMC Children's Hospital of Pittsburgh
Pittsburgh, Pennsylvania, 15213, United States
UPMC Magee Women's Hospital
Pittsburgh, Pennsylvania, 15213, United States
Tribe Clinical Research, LLC- Greer
Greer, South Carolina, 29650, United States
Tribe Clinical Research at Parkside Pediatrics Five Forks
Simpsonville, South Carolina, 29681, United States
Proactive Clinical Research LLC
Edinburg, Texas, 78539, United States
Memorial Hermann Memorial City Hospital
Houston, Texas, 77024, United States
The University of Texas Health Science Center at Houston
Houston, Texas, 77024, United States
Maximos Ob/Gyn
League City, Texas, 77573, United States
Inova Fairfax Medical Campus
Falls Church, Virginia, 22042, United States
Sentara Leigh Hospital
Norfolk, Virginia, 23502, United States
The Group For Women - Kempsville Office
Norfolk, Virginia, 23502, United States
Tidewater Physicians for Women
Norfolk, Virginia, 23502, United States
Womens Care Center
Norfolk, Virginia, 23502, United States
Virginia Physicians For Women (VPFW)
North Chesterfield, Virginia, 23235, United States
Clinical Research Partners, LLC
Richmond, Virginia, 23226, United States
Seattle Childrens Research Institute
Seattle, Washington, 98101, United States
Seattle Childrens Hospital
Seattle, Washington, 98105, United States
UW Medical Center Northwest
Seattle, Washington, 98133, United States
UW Medical Center Montlake
Seattle, Washington, 98195, United States
Fundación Respirar
Ciudad Autónoma de Buenos Aires, Buenos Aires, C1426ABP, Argentina
Clinica Del Niño Y La Madre
Mar del Plata, Buenos Aires, 7600, Argentina
Clinica Privada del Sol S.A
Córdoba, Córdoba Province, X5000IIH, Argentina
Clínica Mayo de Urgencias Médicas Cruz Blanca S.R.L
San Miguel de Tucumán, Tucumán Province, 4000, Argentina
Instituto de Maternidad y Ginecología Nuestra Señora de las Mercedes
San Miguel de Tucumán, Tucumán Province, 4000, Argentina
Centro de investigación Clínica OSECAC - Sede Jonas Salk
Buenos Aires, 1044, Argentina
Equipo Ciencia
Buenos Aires, C1428BNF, Argentina
Centro de Pesquisa Clínica - Obras Sociais Irmã Dulce
Salvador, Estado de Bahia, 41680-430, Brazil
Universidade Federal de Santa Maria.
Santa Maria, Rio Grande do Sul, 97105-900, Brazil
Fundação Faculdade Regional de Medicina de São José do Rio Preto
São José do Rio Preto, São Paulo, 15090000, Brazil
Canadian Center for Vaccinology
Halifax, Nova Scotia, B3K 6R8, Canada
Kingston Health Sciences Centre - Kingston General Site
Kingston, Ontario, K7L 2V7, Canada
CHU de Quebec-Universite Laval-Centre hospitalier de l'Universite Laval et Centre mere-enfant Soleil
Québec, Quebec, G1V 4G2, Canada
FVR, Kokkolan rokotetutkimusklinikka
Kokkola, Keski-Pohjanmaa, 67100, Finland
FVR, Oulun rokotetutkimusklinikka
Oulu, North Ostrobothnia, 90220, Finland
FVR, Tampereen rokotetutkimusklinikka
Tampere, Pirkanmaa, 33100, Finland
FVR, Seinäjoen rokotetutkimusklinikka
Seinäjoki, South Ostrobothnia, 60100, Finland
FVR, Turun rokotetutkimusklinikka
Turku, Southwest Finland, 20520, Finland
MeVac - Meilahti Vaccine Research Center
Helsinki, Uusimaa, 00290, Finland
St.Mary's Hospital
Kurume, Fukuoka, 830-8543, Japan
Sendai City Hospital
Sendai, Miyagi, 982-8502, Japan
Beppu Medical Center
Beppu-shi, Oita Prefecture, 874-0011, Japan
Osaka Habikino Medical Center
Habikino, Osaka, 583-8588, Japan
Taniguchi Hospital
Izumisano, Osaka, 598-0043, Japan
Yamanashi Prefectural Central Hospital
Kofu, Yamanashi, 400-8506, Japan
Fukui Aiiku Hospital
Fukui, 910-0833, Japan
Rakuwakai Otowa Hospital
Kyoto, 607-8062, Japan
Shizuoka General Hospital
Shizuoka, 420-8527, Japan
Panamerican Clinical Research Mexico S.A de C.V. Guadalajara.
Guadalajara, Jalisco, 44670, Mexico
Unidad de Medicina Especializada SMA
San Juan del Río, Querétaro, 76800, Mexico
Jeroen Bosch Hospital
's-Hertogenbosch, North Brabant, 5223 GZ, Netherlands
Josha Research
Bloemfontein, Free State, 9301, South Africa
REIMED Reiger Park
Boksburg, Gauteng, 1459, South Africa
Wits RHI Shandukani Research Centre
Johannesburg, Gauteng, 2001, South Africa
Setshaba Research Centre
Pretoria, Gauteng, 0152, South Africa
Wits Vaccines & Infectious Diseases Analytics (VIDA) Research Unit
Soweto, Gauteng, 1864, South Africa
MRC Unit on Child And Adolescent Health
Cape Town, Western Cape, 7700, South Africa
Gugulethu Green Clinic
Cape Town, Western Cape, 7750, South Africa
Kangwon National University Hospital
Chuncheon, Gangwon-do, 24289, South Korea
Chonnam National University Hospital
Gwangju, Kwangju-kwangyǒkshi, 61469, South Korea
Seoul National University Hospital
Seoul, Seoul-teukbyeolsi [seoul], 03080, South Korea
Korea University Guro Hospital
Seoul, Seoul-teukbyeolsi [seoul], 08308, South Korea
Keimyung University Dongsan Hospital
Daegu, Taegu-kwangyǒkshi, 42601, South Korea
Kyung Hee University Hospital at Gangdong
Seoul, 05278, South Korea
CHUS - Hospital Clinico Universitario
Santiago de Compostela, A Coruña [LA Coruña], 15706, Spain
Hospital Sant Joan de Déu
Esplugues de Llobregat, Barcelona [barcelona], 08950, Spain
Hospital Universitario Quironsalud Madrid
Pozuelo de Alarcón, Madrid, 28223, Spain
Hospital Universitario de Torrejón
Torrejón de Ardoz, Madrid, 28850, Spain
Hospital Universitario La Paz
Madrid, Madrid, Comunidad de, 28046, Spain
Hospital Universitario HM Puerta del Sur
Madrid, Madrid, Comunidad de, 28938, Spain
Hospital Costa del Sol
Marbella, Malaga, 29603, Spain
Hospital Antequera
Antequera, 29200, Spain
Hospital Universitario La Zarzuela
Aravaca, 28023, Spain
Hospital General Universitario Gregorio Marañon
Madrid, 28007, Spain
Hospital Universitario 12 de Octubre
Madrid, 28041, Spain
Hospital Quirónsalud Sagrado Corazón
Seville, 41013, Spain
Instituto Hispalense de Pediatria- IHP1
Seville, 41014, Spain
Hsinchu Municipal Mackay Children's Hospital
Hsinchu, Hsinchu, 30046, Taiwan
Kaohsiung Medical University Chung-Ho Memorial Hospital
Kaohsiung City, 80756, Taiwan
National Taiwan University Hospital
Taipei, 10002, Taiwan
Mackay Memorial Hospital
Taipei, 10449, Taiwan
Chang Gung Medical Foundation-Linkou Branch
Taoyuan, 333, Taiwan
University Hospitals Bristol NHS Foundation Trust
Bristol, Bristol, CITY of, BS1 3NU, United Kingdom
St Michael's Hospital
Bristol, Bristol, CITY of, BS2 8EG, United Kingdom
Barnet Hospital
London, England, EN5 3DJ, United Kingdom
St. George's Hospital
London, England, SW17 0QT, United Kingdom
North Manchester General Hospital
Manchester, England, M8 5RB., United Kingdom
The Royal Cornwall Hospital
Truro, England, TR1 3LJ, United Kingdom
Southampton General Hospital
Southampton, Hampshire, SO16 6YD, United Kingdom
St Mary's Hospital (Manchester University NHS Foundation Trust)
Manchester, Lancashire, M13 9WL, United Kingdom
Imperial College Healthcare NHS Foundation Trust - St Mary's Hospital
London, London, CITY of, W2 1NY, United Kingdom
The John Radcliffe Hospital
Oxford, Oxfordshire, OX3 9DU, United Kingdom
The Princess Royal Hospital
Shropshire, Telford AND Wrekin, TF1 6TF, United Kingdom
Bristol Royal Hospital for Children
Bristol, BS2 8BJ, United Kingdom
Bristol Royal Infirmary
Bristol, BS2 8EX, United Kingdom
St James's University Hospital
Leeds, LS9 7TF, United Kingdom
Royal Free Hospital
London, NW32QG, United Kingdom
Wythenshawe Hospital
Manchester, M23 9LT, United Kingdom
Related Links
MeSH Terms
Interventions
Intervention Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Pfizer CT.gov Call Center
Pfizer
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 3
- Allocation
- RANDOMIZED
- Masking
- QUADRUPLE
- Who Masked
- PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
- Purpose
- PREVENTION
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
August 14, 2025
First Posted
September 8, 2025
Study Start
August 25, 2025
Primary Completion (Estimated)
November 6, 2028
Study Completion (Estimated)
March 2, 2029
Last Updated
May 5, 2026
Record last verified: 2026-05
Data Sharing
- IPD Sharing
- Will share
Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.