A Phase 3 interventional study of RSVPreF3 vaccine and Control in Respiratory Syncytial Virus Infections, sponsored by GlaxoSmithKline. Completed at 138 sites in 23 countries. Open to female participants aged 9 Years to 49 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-03-17.
Sponsored by GlaxoSmithKline · Phase 3, Interventional, and Other
The purpose of this follow-up study was to describe the safety in subsequent pregnancies in participants who were previously administered the RSVPreF3 maternal vaccine or control during any prior RSV MAT study.
The study participants enrolled in this follow-up study received RSVPreF3 maternal vaccination (any dose) or controls during the following prior RSV MAT studies: RSV MAT-001 (NCT03674177), RSV MAT-004 (NCT04126213), RSV MAT-010 (NCT05045144), RSV MAT-011 (NCT04138056), RSV MAT-009 (NCT04605159), RSV MAT-012 (NCT04980391) and RSV MAT-039 (NCT05169905).
No intervention was administered in this study. The exposure was the intervention (either RSVPreF3 vaccine or control) received by the study participants in the abovementioned prior RSV MAT studies.
Retrospective cohort
Adult/Adolescent Participant:
Study participant:
Infant Participant:
Prospective cohort
Adult/Adolescent Participant:
Study participant:
Infant Participant:
Exclusion Criteria:
Adult/adolescent participant otherwise eligible for the prospective cohort:
Infant participant:
Maternal participants who received the RSVPreF3 vaccine during the prior RSV MAT studies (RSV MAT-001, RSV MAT-004, RSV MAT-009, RSV MAT-010, RSV MAT-011, RSV MAT-012 and RSV MAT-039) according to the vaccination schedule specific to each study.
Biological: RSVPreF3 vaccine
Maternal participants who received any control (placebo, Tdap or influenza vaccine) during the prior RSV MAT studies (RSV MAT-001, RSV MAT-004, RSV MAT-009, RSV MAT-010, RSV MAT-011, RSV MAT-012 and RSV MAT-039) according to the vaccination schedule specific to each study.
Other: Control
This group consisted of infants live-born to maternal participants in the RSV MAT Group - Mother.
This group consisted of infants live-born to maternal participants in the Control Group - Mother.
No intervention was administered in this extension study. Participants received the RSVPreF3 vaccine during the prior RSV MAT studies (RSV MAT-001, RSV MAT-004, RSV MAT-010, RSV MAT-011, RSV MAT-009, RSV MAT-012 and RSV MAT-039) according to the vaccination schedule specific to each study. In all prior RSV MAT studies, participants received one dose of RSVPreF3 vaccine except in RSV MAT-011 study, where some participants received a second dose as well.
No intervention was administered in this extension study. Participants received any control (placebo, Tdap or influenza vaccine) during the prior RSV MAT studies (RSV MAT-001, RSV MAT-004, RSV MAT-010, RSV MAT-011, RSV MAT-009, RSV MAT-012 and RSV MAT-039) according to the vaccination schedule specific to each study. In all prior RSV MAT studies, participants received one dose of any control (placebo, Tdap or influenza vaccine).
Number of Maternal Participants With Pregnancy Outcomes From Conception Until Day 42 Post-delivery of the First Pregnancy Conceived Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
Assessed pregnancy outcomes were live infant with no apparent congenital anomaly; spontaneous abortion with no apparent congenital anomaly; ectopic pregnancy; elective termination with no apparent congenital anomaly; live infant with congenital anomaly, and stillbirth with congenital anomaly. Due to the character limit, further description is added here instead of Analysis population description field: 1 participant in the Control group - Mother was excluded from this outcome's analysis as the gestational age was not provided and hence conception date, which is required for this outcome measure, could not be calculated.
Time frame: From conception until Day 42 post-delivery of the first pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Maternal Participants With Pregnancy-related Adverse Events of Special Interest (AESIs) From Conception Until Day 42 Post-delivery of the First Pregnancy Conceived Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
Assessed pregnancy-related AESIs were chorioamnionitis, fetal growth restriction, gestational diabetes mellitus, gestational hypertension, pre-eclampsia, pre-eclampsia with severe features including eclampsia, premature preterm ruptures of membranes, preterm labor and provider-initiated preterm birth. Due to the character limit, further description is added here instead of Analysis population description field: 1 participant in the Control group - Mother was excluded from this outcome's analysis as the gestational age was not provided and hence conception date, which is required for this outcome measure, could not be calculated.
Time frame: From conception until Day 42 post-delivery of the first pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Infant Participants With AESIs From Birth Until Day 42 Post-birth of the First Pregnancy Conceived Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
Assessed AESIs were congenital anomalies with internal structural defects, congenital anomalies with major external structural defects, low birth weight \[greater than or equal to (\>=) 1500 grams (G) and below (\<) 2500 G\], very low birth weight (\>=1000 G and \<1500 G), neonatal death in a term live birth (\>=37 weeks of gestational age), preterm birth (\<37 weeks of gestational age) and small for gestational age.
Time frame: From birth until Day 42 post-birth of the first pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Pregnancies With Pregnancy Outcomes From Conception Until Day 42 Post-delivery of Any Pregnancy Conceived by Maternal Participants Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
Assessed pregnancy outcomes were live infant with no apparent congenital anomaly; spontaneous abortion with no apparent congenital anomaly; ectopic pregnancy; elective termination with no apparent congenital anomaly; live infant with congenital anomaly; molar pregnancy; stillbirth with congenital anomaly and stillbirth with no apparent congenital anomaly. Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, pregnancy outcomes were calculated based on the number of pregnancies observed from the maternal participants.
Time frame: From conception until Day 42 post-delivery of any pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Pregnancies With Pregnancy-related AESIs From Conception Until Day 42 Post-delivery of Any Pregnancy Conceived by Maternal Participants Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
Assessed pregnancy-related AESIs were preterm labor, provider-initiated preterm birth, premature preterm rupture of membranes, gestational diabetes mellitus, gestational hypertension, pre-eclampsia with severe features including eclampsia, pre-eclampsia, fetal growth restriction and chorioamnionitis. Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, pregnancy-related AESIs were calculated based on the number of pregnancies observed from the maternal participants.
Time frame: From conception until Day 42 post-delivery of any pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Infant Participants With AESIs From Birth Until Day 42 Post-birth of Any Pregnancy Conceived Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
Assessed AESIs were congenital anomalies with internal structural defects, congenital anomalies with major external structural defects, low birth weight (\>=1500 G and \<2500 G), very low birth weight (\>=1000 G and \<1500 G), neonatal death in a term live birth (\>=37 weeks of gestational age), preterm birth (\<37 weeks of gestational age) and small for gestational age.
Time frame: From birth until Day 42 post-birth of any pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Pregnancies With Preterm Birth Event Data Stratified by Selected Risk Factors, From Day 1 Until Day 42 Post-delivery of Any Pregnancy Conceived by Maternal Participants Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The selected risk factors assessed were prior preterm delivery, pregnancy complications, gestational diabetes mellitus, chorioamnionitis during pregnancy, hypertensive disorders of pregnancy, pre-existing hypertension, pre-existing diabetes, vaginal bleeding during pregnancy, polyhydramnios or oligohydramnios during pregnancy and fetal growth restriction. The below presented data is read as follows: Yes = the respective risk factor was experienced by the maternal participant in the past and/or during pregnancy. No = the respective risk factor was not experienced by the maternal participant in the past and/or during pregnancy. With preterm birth event = the assessed pregnancy resulted in a preterm birth event. Without preterm birth event = the assessed pregnancy did not result in a preterm birth event. As pre-specified in the SAP, preterm birth event data stratified by selected risk factors was calculated based on the number of pregnancies observed from the maternal participants.
Time frame: From Day 1 until Day 42 post-delivery of any pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Pregnancies With Preterm Birth Event Data Stratified by Age Group at Vaccination, From Day 1 Until Day 42 Post-delivery of Any Pregnancy Conceived by Maternal Participants Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The age groups at vaccination assessed were \<18 years, 18-24 years, 25-34 years and \>=35 years. Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, preterm birth event data stratified by age group at vaccination was calculated based on the number of pregnancies observed from the maternal participants.
Time frame: From Day 1 until Day 42 post-delivery of any pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Pregnancies With Preterm Birth Event Data Stratified by Pre-pregnancy BMI, From Day 1 Until Day 42 Post-delivery of Any Pregnancy Conceived by Maternal Participants Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The pre-pregnancy body mass index (BMI) categories assessed were \< 30 kilogram per square meter (kg/m\^2), \>=30 kg/m\^2 and missing (no pre-pregnancy BMI data available). Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, preterm birth event data stratified by pre-pregnancy BMI was calculated based on the number of pregnancies observed from the maternal participants.
Time frame: From Day 1 until Day 42 post-delivery of any pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Pregnancies With Preterm Birth Event Data Stratified by Race, From Day 1 Until Day 42 Post-delivery of Any Pregnancy Conceived by Maternal Participants Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The races assessed were American Indian or Alaska Native, Asian, Black or African American, Native Hawaiian or Other Pacific Islander, White, Multiple, Not reported and Unknown. Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, preterm birth event data stratified by race was calculated based on the number of pregnancies observed from the maternal participants.
Time frame: From Day 1 until Day 42 post-delivery of any pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Pregnancies With Preterm Birth Event Data Stratified by Multiple Gestation Pregnancy, From Day 1 Until Day 42 Post-delivery of Any Pregnancy Conceived by Maternal Participants Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The multiple gestation pregnancies assessed were one gestation, two gestations and three gestations. Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, preterm birth event data stratified by multiple gestation pregnancy was calculated based on the number of pregnancies observed from the maternal participants.
Time frame: From Day 1 until Day 42 post-delivery of any pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Pregnancies With Preterm Birth Event Data Stratified by Geographic Region, From Day 1 Until Day 42 Post-delivery of Any Pregnancy Conceived by Maternal Participants Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The geographic regions assessed were Europe, Australasia, North America, Latin America and Africa. Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, preterm birth event data stratified by geographic region was calculated based on the number of pregnancies observed from the maternal participants.
Time frame: From Day 1 until Day 42 post-delivery of any pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Pregnancies With Preterm Birth Event Data Stratified by Economic Region, From Day 1 Until Day 42 Post-delivery of Any Pregnancy Conceived by Maternal Participants Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The economic regions assessed were low and middle-income countries (LMIC) and high-income countries (HIC). Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, preterm birth event data stratified by economic region was calculated based on the number of pregnancies observed from the maternal participants.
Time frame: From Day 1 until Day 42 post-delivery of any pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Maternal Participants With Preterm Birth Event Data Stratified by Selected Risk Factors, From Day 1 Until Day 42 Post-delivery of the First Pregnancy Conceived Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The selected risk factors assessed were prior preterm delivery, pregnancy complications, gestational diabetes mellitus, chorioamnionitis during pregnancy, hypertensive disorders of pregnancy, pre-existing hypertension, pre-existing diabetes, vaginal bleeding during pregnancy, polyhydramnios or oligohydramnios during pregnancy and fetal growth restriction. The below presented data is read as follows: Yes = the respective risk factor was experienced by the maternal participant in the past and/or during pregnancy. No = the respective risk factor was not experienced by the maternal participant in the past and/or during pregnancy. With preterm birth event = the assessed pregnancy resulted in a preterm birth event. Without preterm birth event = the assessed pregnancy did not result in a preterm birth event.
Time frame: From Day 1 until Day 42 post-delivery of the first pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Maternal Participants With Preterm Birth Event Data Stratified by Age Group at Vaccination, From Day 1 Until Day 42 Post-delivery of the First Pregnancy Conceived Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The age groups at vaccination assessed were \<18 years, 18-24 years, 25-34 years and \>=35 years.
Time frame: From Day 1 until Day 42 post-delivery of the first pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Maternal Participants With Preterm Birth Event Data Stratified by Pre-pregnancy BMI Group, From Day 1 Until Day 42 Post-delivery of the First Pregnancy Conceived Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The pre-pregnancy BMI categories assessed were \< 30 kilogram per square meter (kg/m\^2), \>=30 kg/m\^2 and missing (no pre-pregnancy BMI data available).
Time frame: From Day 1 until Day 42 post-delivery of the first pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Maternal Participants With Preterm Birth Event Data Stratified by Race, From Day 1 Until Day 42 Post-delivery of the First Pregnancy Conceived Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The races assessed were American Indian or Alaska Native, Asian, Black or African American, Native Hawaiian or Other Pacific Islander, White, Multiple, Not reported and Unknown.
Time frame: From Day 1 until Day 42 post-delivery of the first pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Maternal Participants With Preterm Birth Event Data Stratified by Multiple Gestation Pregnancy, From Day 1 Until Day 42 Post-delivery of the First Pregnancy Conceived Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The multiple gestation pregnancies assessed were one gestation and two gestations.
Time frame: From Day 1 until Day 42 post-delivery of the first pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Maternal Participants With Preterm Birth Event Data Stratified by Geographic Region, From Day 1 Until Day 42 Post-delivery of the First Pregnancy Conceived Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The geographic regions assessed were Europe, Australasia, North America, Latin America and Africa.
Time frame: From Day 1 until Day 42 post-delivery of the first pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
Number of Maternal Participants With Preterm Birth Event Data Stratified by Economic Region, From Day 1 Until Day 42 Post-delivery of the First Pregnancy Conceived Within 2 Years Post-vaccination Received in Prior RSV MAT Studies
The economic regions assessed were LMIC and HIC.
Time frame: From Day 1 until Day 42 post-delivery of the first pregnancy conceived within 2 years post-vaccination received in prior RSV MAT studies
A total of 3855 participants (3398 maternal participants and 457 infants) completed the informed consent process, of which 475 maternal participants with pregnancy conceived within and beyond 2 years post-vaccination in prior RSV MAT studies and 438 infants born those maternal participants with post-birth data available were included in the current study's Maternal Full Analysis Set (FAS) and Infant FAS respectively.
| Milestone | RSV MAT Group - Mother | Control Group - Mother | RSV MAT Group - Infant | Control Group - Infant |
|---|---|---|---|---|
| Started | 296 | 152 | 275 | 136 |
| Completed | 269 | 136 | 256 | 118 |
| Not completed | 27 | 16 | 19 | 18 |
| Withdrew: Migrated / moved from the study area | 0 | 1 | 0 | 0 |
| Withdrew: Lost to follow-up | 4 | 3 | 1 | 1 |
| Withdrew: Adverse event leading to study discontinuation | 1 | 0 | 0 | 0 |
| Withdrew: Physician decision | 4 | 0 | 0 | 0 |
| Withdrew: Other | 18 | 12 | 17 | 17 |
| Withdrew: Death | 0 | 0 | 1 | 0 |
Assessed pregnancy outcomes were live infant with no apparent congenital anomaly; spontaneous abortion with no apparent congenital anomaly; ectopic pregnancy; elective termination with no apparent congenital anomaly; live infant with congenital anomaly, and stillbirth with congenital anomaly. Due to the character limit, further description is added here instead of Analysis population description field: 1 participant in the Control group - Mother was excluded from this outcome's analysis as the gestational age was not provided and hence conception date, which is required for this outcome measure, could not be calculated.
| Participants | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| Live infant with no apparent congenital anomaly | 249 | 120 |
| Spontaneous abortion with no apparent congenital anomaly | 28 | 14 |
| Ectopic pregnancy | 1 | 1 |
| Elective termination with no apparent congenital anomaly | 1 | 2 |
| Live infant with congenital anomaly | 17 | 13 |
| Stillbirth with congenital anomaly | 0 | 1 |
Assessed pregnancy-related AESIs were chorioamnionitis, fetal growth restriction, gestational diabetes mellitus, gestational hypertension, pre-eclampsia, pre-eclampsia with severe features including eclampsia, premature preterm ruptures of membranes, preterm labor and provider-initiated preterm birth. Due to the character limit, further description is added here instead of Analysis population description field: 1 participant in the Control group - Mother was excluded from this outcome's analysis as the gestational age was not provided and hence conception date, which is required for this outcome measure, could not be calculated.
| Participants | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| Chorioamnionitis | 2 | 0 |
| Fetal growth restriction | 3 | 3 |
| Gestational diabetes mellitus | 12 | 7 |
| Gestational hypertension | 8 | 1 |
| Pre-eclampsia | 0 | 2 |
| Pre-eclampsia with severe features including eclampsia | 2 | 3 |
| Premature preterm ruptures of membrane | 2 | 1 |
| Preterm labor | 11 | 3 |
| Provider-initiated preterm birth | 10 | 3 |
Assessed AESIs were congenital anomalies with internal structural defects, congenital anomalies with major external structural defects, low birth weight \[greater than or equal to (\>=) 1500 grams (G) and below (\<) 2500 G\], very low birth weight (\>=1000 G and \<1500 G), neonatal death in a term live birth (\>=37 weeks of gestational age), preterm birth (\<37 weeks of gestational age) and small for gestational age.
| Participants | RSV MAT Group - Infant | Control Group - Infant |
|---|---|---|
| Congenital anomalies with internal structural defects | 3 | 0 |
| Congenital anomalies with major external structural defects | 1 | 0 |
| Low birth weight (>=1500 G and <2500 G) | 18 | 5 |
| Very low birth weight (>=1000 G and <1500 G) | 1 | 1 |
| Neonatal death in a term live birth (>=37 weeks of gestational age) | 1 | 0 |
| Preterm birth (<37 weeks of gestational age) | 23 | 8 |
| Small for gestational age | 18 | 13 |
Assessed pregnancy outcomes were live infant with no apparent congenital anomaly; spontaneous abortion with no apparent congenital anomaly; ectopic pregnancy; elective termination with no apparent congenital anomaly; live infant with congenital anomaly; molar pregnancy; stillbirth with congenital anomaly and stillbirth with no apparent congenital anomaly. Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, pregnancy outcomes were calculated based on the number of pregnancies observed from the maternal participants.
| Pregnancies | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| Live infant with no apparent congenital anomaly | 257 | 123 |
| Spontaneous abortion with no apparent congenital anomaly | 31 | 16 |
| Ectopic pregnancy | 1 | 1 |
| Elective termination with no apparent congenital anomaly | 1 | 2 |
| Live infant with congenital anomaly | 18 | 14 |
| Molar pregnancy | 1 | 1 |
| Stillbirth with congenital anomaly | 0 | 1 |
| Stillbirth with no apparent congenital anomaly | 1 | 0 |
Assessed pregnancy-related AESIs were preterm labor, provider-initiated preterm birth, premature preterm rupture of membranes, gestational diabetes mellitus, gestational hypertension, pre-eclampsia with severe features including eclampsia, pre-eclampsia, fetal growth restriction and chorioamnionitis. Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, pregnancy-related AESIs were calculated based on the number of pregnancies observed from the maternal participants.
| Pregnancies | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| Preterm labor | 12 | 3 |
| Provider-initiated preterm birth | 10 | 3 |
| Premature preterm ruptures of membranes | 2 | 1 |
| Gestational diabetes mellitus | 12 | 8 |
| Gestational hypertension | 10 | 1 |
| Pre-eclampsia with severe features including eclampsia | 3 | 3 |
| Pre-eclampsia | 1 | 2 |
| Fetal growth restriction | 4 | 3 |
| Chorioamnionitis | 2 | 0 |
Assessed AESIs were congenital anomalies with internal structural defects, congenital anomalies with major external structural defects, low birth weight (\>=1500 G and \<2500 G), very low birth weight (\>=1000 G and \<1500 G), neonatal death in a term live birth (\>=37 weeks of gestational age), preterm birth (\<37 weeks of gestational age) and small for gestational age.
| Participants | RSV MAT Group - Infant | Control Group - Infant |
|---|---|---|
| Congenital anomalies with internal structural defects | 4 | 0 |
| Congenital anomalies with major external structural defects | 1 | 0 |
| Low birth weight (>=1500 G and <2500 G) | 20 | 5 |
| Very low birth weight (>=1000 G and <1500 G) | 1 | 1 |
| Neonatal death in a term live birth (>=37 weeks of gestational age) | 1 | 0 |
| Preterm birth (<37 weeks of gestational age) | 24 | 8 |
| Small for gestational age | 20 | 13 |
The selected risk factors assessed were prior preterm delivery, pregnancy complications, gestational diabetes mellitus, chorioamnionitis during pregnancy, hypertensive disorders of pregnancy, pre-existing hypertension, pre-existing diabetes, vaginal bleeding during pregnancy, polyhydramnios or oligohydramnios during pregnancy and fetal growth restriction. The below presented data is read as follows: Yes = the respective risk factor was experienced by the maternal participant in the past and/or during pregnancy. No = the respective risk factor was not experienced by the maternal participant in the past and/or during pregnancy. With preterm birth event = the assessed pregnancy resulted in a preterm birth event. Without preterm birth event = the assessed pregnancy did not result in a preterm birth event. As pre-specified in the SAP, preterm birth event data stratified by selected risk factors was calculated based on the number of pregnancies observed from the maternal participants.
| Pregnancies | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| Prior preterm delivery — Yes: With preterm birth event | 5 | 1 |
| Prior preterm delivery — Yes: Without preterm birth event | 2 | 3 |
| Prior preterm delivery — No: With preterm birth event | 18 | 6 |
| Prior preterm delivery — No: Without preterm birth event | 250 | 127 |
| Pregnancy complications — Yes: With preterm birth event | 4 | 0 |
| Pregnancy complications — Yes: Without preterm birth event | 28 | 16 |
| Pregnancy complications — No: With preterm birth event | 19 | 7 |
| Pregnancy complications — No: Without preterm birth event | 224 | 114 |
| Gestational diabetes mellitus — Yes: With preterm birth event | 0 | 0 |
| Gestational diabetes mellitus — Yes: Without preterm birth event | 13 | 8 |
| Gestational diabetes mellitus — No: With preterm birth event | 23 | 7 |
| Gestational diabetes mellitus — No: Without preterm birth event | 239 | 122 |
| Chorioamnionitis during pregnancy — Yes: With preterm birth event | 0 | 0 |
| Chorioamnionitis during pregnancy — Yes: Without preterm birth event | 2 | 0 |
| Chorioamnionitis during pregnancy — No: With preterm birth event | 23 | 7 |
| Chorioamnionitis during pregnancy — No: Without preterm birth event | 250 | 130 |
| Hypertensive disorders of pregnancy — Yes: With preterm birth event | 0 | 0 |
| Hypertensive disorders of pregnancy — Yes: Without preterm birth event | 0 | 0 |
| Hypertensive disorders of pregnancy — No: With preterm birth event | 23 | 7 |
| Hypertensive disorders of pregnancy — No: Without preterm birth event | 252 | 130 |
| Pre-existing hypertension — Yes: With preterm birth event | 1 | 0 |
| Pre-existing hypertension — Yes: Without preterm birth event | 1 | 2 |
| Pre-existing hypertension — No: With preterm birth event | 22 | 7 |
| Pre-existing hypertension — No: Without preterm birth event | 251 | 128 |
| Pre-existing diabetes — Yes: With preterm birth event | 1 | 0 |
| Pre-existing diabetes — Yes: Without preterm birth event | 0 | 0 |
| Pre-existing diabetes — No: With preterm birth event | 22 | 7 |
| Pre-existing diabetes — No: Without preterm birth event | 252 | 130 |
| Vaginal bleeding during pregnancy — Yes: With preterm birth event | 1 | 0 |
| Vaginal bleeding during pregnancy — Yes: Without preterm birth event | 5 | 2 |
| Vaginal bleeding during pregnancy — No: With preterm birth event | 22 | 7 |
| Vaginal bleeding during pregnancy — No: Without preterm birth event | 247 | 128 |
| Polyhydramnios or oligohydramnios during pregnancy — Yes: With preterm birth event | 1 | 0 |
| Polyhydramnios or oligohydramnios during pregnancy — Yes: Without preterm birth event | 3 | 1 |
| Polyhydramnios or oligohydramnios during pregnancy — No: With preterm birth event | 22 | 7 |
| Polyhydramnios or oligohydramnios during pregnancy — No: Without preterm birth event | 249 | 129 |
| Fetal growth restriction — Yes: With preterm birth event | 0 | 0 |
| Fetal growth restriction — Yes: Without preterm birth event | 4 | 3 |
| Fetal growth restriction — No: With preterm birth event | 23 | 7 |
| Fetal growth restriction — No: Without preterm birth event | 248 | 127 |
The age groups at vaccination assessed were \<18 years, 18-24 years, 25-34 years and \>=35 years. Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, preterm birth event data stratified by age group at vaccination was calculated based on the number of pregnancies observed from the maternal participants.
| Pregnancies | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| <18 years: With preterm birth event | 0 | 0 |
| <18 years: Without preterm birth event | 2 | 0 |
| 18-24 years: With preterm birth event | 11 | 2 |
| 18-24 years: Without preterm birth event | 61 | 23 |
| 25-34 years: With preterm birth event | 11 | 4 |
| 25-34 years: Without preterm birth event | 156 | 85 |
| >= 35 years: With preterm birth event | 1 | 1 |
| >= 35 years: Without preterm birth event | 33 | 22 |
The pre-pregnancy body mass index (BMI) categories assessed were \< 30 kilogram per square meter (kg/m\^2), \>=30 kg/m\^2 and missing (no pre-pregnancy BMI data available). Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, preterm birth event data stratified by pre-pregnancy BMI was calculated based on the number of pregnancies observed from the maternal participants.
| Pregnancies | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| <30 kg/m^2: With preterm birth event | 10 | 2 |
| <30 kg/m^2: Without preterm birth event | 163 | 87 |
| >=30 kg/m^2: With preterm birth event | 1 | 3 |
| >=30 kg/m^2: Without preterm birth event | 38 | 10 |
| Missing: With preterm birth event | 12 | 2 |
| Missing: Without preterm birth event | 51 | 33 |
The races assessed were American Indian or Alaska Native, Asian, Black or African American, Native Hawaiian or Other Pacific Islander, White, Multiple, Not reported and Unknown. Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, preterm birth event data stratified by race was calculated based on the number of pregnancies observed from the maternal participants.
| Pregnancies | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| American Indian or Alaska Native: With preterm birth event | 0 | 1 |
| American Indian or Alaska Native: Without preterm birth event | 5 | 8 |
| Asian: With preterm birth event | 6 | 0 |
| Asian: Without preterm birth event | 33 | 20 |
| Black or African American: With preterm birth event | 1 | 1 |
| Black or African American: Without preterm birth event | 14 | 6 |
| Native Hawaiian or Other Pacific Islander: With preterm birth event | 0 | 0 |
| Native Hawaiian or Other Pacific Islander: Without preterm birth event | 3 | 1 |
| White: With preterm birth event | 10 | 4 |
| White: Without preterm birth event | 178 | 88 |
| Multiple: With preterm birth event | 3 | 0 |
| Multiple: Without preterm birth event | 10 | 5 |
| Not reported: With preterm birth event | 0 | 1 |
| Not reported: Without preterm birth event | 2 | 0 |
| Unknown: With preterm birth event | 3 | 0 |
| Unknown: Without preterm birth event | 7 | 2 |
The multiple gestation pregnancies assessed were one gestation, two gestations and three gestations. Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, preterm birth event data stratified by multiple gestation pregnancy was calculated based on the number of pregnancies observed from the maternal participants.
| Pregnancies | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| One gestation: With preterm birth event | 22 | 7 |
| One gestation: Without preterm birth event | 242 | 125 |
| Two gestations: With preterm birth event | 1 | 0 |
| Two gestations: Without preterm birth event | 8 | 5 |
| Three gestations: With preterm birth event | 0 | 0 |
| Three gestations: Without preterm birth event | 2 | 0 |
The geographic regions assessed were Europe, Australasia, North America, Latin America and Africa. Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, preterm birth event data stratified by geographic region was calculated based on the number of pregnancies observed from the maternal participants.
| Pregnancies | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| Europe: With preterm birth event | 6 | 3 |
| Europe: Without preterm birth event | 93 | 51 |
| Australasia: With preterm birth event | 6 | 0 |
| Australasia: Without preterm birth event | 43 | 25 |
| North America: With preterm birth event | 4 | 1 |
| North America: Without preterm birth event | 72 | 31 |
| Latin America: With preterm birth event | 7 | 2 |
| Latin America: Without preterm birth even | 36 | 20 |
| Africa: With preterm birth event | 0 | 1 |
| Africa: Without preterm birth event | 8 | 3 |
The economic regions assessed were low and middle-income countries (LMIC) and high-income countries (HIC). Due to the character limit, further description is added here instead of Analysis population description field: As pre-specified in the SAP, preterm birth event data stratified by economic region was calculated based on the number of pregnancies observed from the maternal participants.
| Pregnancies | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| LMIC: With preterm birth event | 13 | 3 |
| LMIC: Without preterm birth event | 66 | 38 |
| HIC: With preterm birth event | 10 | 4 |
| HIC: Without preterm birth event | 186 | 92 |
The selected risk factors assessed were prior preterm delivery, pregnancy complications, gestational diabetes mellitus, chorioamnionitis during pregnancy, hypertensive disorders of pregnancy, pre-existing hypertension, pre-existing diabetes, vaginal bleeding during pregnancy, polyhydramnios or oligohydramnios during pregnancy and fetal growth restriction. The below presented data is read as follows: Yes = the respective risk factor was experienced by the maternal participant in the past and/or during pregnancy. No = the respective risk factor was not experienced by the maternal participant in the past and/or during pregnancy. With preterm birth event = the assessed pregnancy resulted in a preterm birth event. Without preterm birth event = the assessed pregnancy did not result in a preterm birth event.
| Participants | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| Prior preterm delivery — Yes: With preterm birth event | 5 | 1 |
| Prior preterm delivery — Yes: Without preterm birth event | 2 | 3 |
| Prior preterm delivery — No: With preterm birth event | 17 | 6 |
| Prior preterm delivery — No: Without preterm birth event | 242 | 123 |
| Pregnancy complications — Yes: With preterm birth event | 4 | 0 |
| Pregnancy complications — Yes: Without preterm birth event | 27 | 15 |
| Pregnancy complications — No: With preterm birth event | 18 | 7 |
| Pregnancy complications — No: Without preterm birth event | 217 | 111 |
| Gestational diabetes mellitus — Yes: With preterm birth event | 0 | 0 |
| Gestational diabetes mellitus — Yes: Without preterm birth event | 13 | 7 |
| Gestational diabetes mellitus — No: With preterm birth event | 22 | 7 |
| Gestational diabetes mellitus — No: Without preterm birth event | 231 | 119 |
| Chorioamnionitis during pregnancy — Yes: With preterm birth event | 0 | 0 |
| Chorioamnionitis during pregnancy — Yes: Without preterm birth event | 2 | 0 |
| Chorioamnionitis during pregnancy — No: With preterm birth event | 22 | 7 |
| Chorioamnionitis during pregnancy — No: Without preterm birth event | 242 | 126 |
| Hypertensive disorders of pregnancy — Yes: With preterm birth event | 0 | 0 |
| Hypertensive disorders of pregnancy — Yes: Without preterm birth event | 0 | 0 |
| Hypertensive disorders of pregnancy — No: With preterm birth event | 22 | 7 |
| Hypertensive disorders of pregnancy — No: Without preterm birth event | 244 | 126 |
| Pre-existing hypertension — Yes: With preterm birth event | 1 | 0 |
| Pre-existing hypertension — Yes: Without preterm birth event | 1 | 2 |
| Pre-existing hypertension — No: With preterm birth event | 21 | 7 |
| Pre-existing hypertension — No: Without preterm birth event | 243 | 124 |
| Pre-existing diabetes — Yes: With preterm birth event | 1 | 0 |
| Pre-existing diabetes — Yes: Without preterm birth event | 0 | 0 |
| Pre-existing diabetes — No: With preterm birth event | 21 | 7 |
| Pre-existing diabetes — No: Without preterm birth event | 244 | 126 |
| Vaginal bleeding during pregnancy — Yes: With preterm birth event | 1 | 0 |
| Vaginal bleeding during pregnancy — Yes: Without preterm birth event | 5 | 2 |
| Vaginal bleeding during pregnancy — No: With preterm birth event | 21 | 7 |
| Vaginal bleeding during pregnancy — No: Without preterm birth event | 239 | 124 |
| Polyhydramnios or oligohydramnios during pregnancy — Yes: With preterm birth event | 1 | 0 |
| Polyhydramnios or oligohydramnios during pregnancy — Yes: Without preterm birth event | 3 | 1 |
| Polyhydramnios or oligohydramnios during pregnancy — No: With preterm birth event | 21 | 7 |
| Polyhydramnios or oligohydramnios during pregnancy — No: Without preterm birth event | 241 | 125 |
| Fetal growth restriction — Yes: With preterm birth event | 0 | 0 |
| Fetal growth restriction — Yes: Without preterm birth event | 3 | 3 |
| Fetal growth restriction — No: With preterm birth event | 22 | 7 |
| Fetal growth restriction — No: Without preterm birth event | 241 | 123 |
The age groups at vaccination assessed were \<18 years, 18-24 years, 25-34 years and \>=35 years.
| Participants | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| <18 years: With preterm birth event | 0 | 0 |
| <18 years: Without preterm birth event | 2 | 0 |
| 18-24 years: With preterm birth event | 11 | 2 |
| 18-24 years: Without preterm birth event | 61 | 22 |
| 25-34 years: With preterm birth event | 10 | 4 |
| 25-34 years: Without preterm birth event | 149 | 83 |
| >= 35 years: With preterm birth event | 1 | 1 |
| >= 35 years: Without preterm birth event | 32 | 21 |
The pre-pregnancy BMI categories assessed were \< 30 kilogram per square meter (kg/m\^2), \>=30 kg/m\^2 and missing (no pre-pregnancy BMI data available).
| Participants | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| <30 kg/m^2: With preterm birth event | 10 | 2 |
| <30 kg/m^2: Without preterm birth event | 161 | 87 |
| >=30 kg/m^2: With preterm birth event | 1 | 3 |
| >=30 kg/m^2: Without preterm birth event | 38 | 10 |
| Missing: With preterm birth event | 11 | 2 |
| Missing: Without preterm birth event | 45 | 29 |
The races assessed were American Indian or Alaska Native, Asian, Black or African American, Native Hawaiian or Other Pacific Islander, White, Multiple, Not reported and Unknown.
| Participants | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| American Indian or Alaska Native: With preterm birth event | 0 | 1 |
| American Indian or Alaska Native: Without preterm birth event | 5 | 8 |
| Asian: With preterm birth event | 6 | 0 |
| Asian: Without preterm birth event | 33 | 20 |
| Black or African American: With preterm birth event | 1 | 1 |
| Black or African American: Without preterm birth event | 14 | 6 |
| Native Hawaiian or Other Pacific Islander: With preterm birth event | 0 | 0 |
| Native Hawaiian or Other Pacific Islander: Without preterm birth event | 3 | 1 |
| White: With preterm birth event | 9 | 4 |
| White: Without preterm birth event | 170 | 84 |
| Multiple: With preterm birth event | 3 | 0 |
| Multiple: Without preterm birth event | 10 | 5 |
| Not reported: With preterm birth event | 0 | 1 |
| Not reported: Without preterm birth event | 2 | 0 |
| Unknown: With preterm birth event | 3 | 0 |
| Unknown: Without preterm birth event | 7 | 2 |
The multiple gestation pregnancies assessed were one gestation and two gestations.
| Participants | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| One gestation: With preterm birth event | 22 | 7 |
| One gestation: Without preterm birth event | 242 | 125 |
| Two gestations: With preterm birth event | 0 | 0 |
| Two gestations: Without preterm birth event | 2 | 1 |
The geographic regions assessed were Europe, Australasia, North America, Latin America and Africa.
| Participants | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| Europe: With preterm birth event | 5 | 3 |
| Europe: Without preterm birth event | 90 | 50 |
| Australasia: With preterm birth event | 6 | 0 |
| Australasia: Without preterm birth event | 42 | 25 |
| North America: With preterm birth event | 4 | 1 |
| North America: Without preterm birth event | 68 | 28 |
| Latin America: With preterm birth event | 7 | 2 |
| Latin America: Without preterm birth even | 36 | 20 |
| Africa: With preterm birth event | 0 | 1 |
| Africa: Without preterm birth event | 8 | 3 |
The economic regions assessed were LMIC and HIC.
| Participants | RSV MAT Group - Mother | Control Group - Mother |
|---|---|---|
| LMIC: With preterm birth event | 13 | 3 |
| LMIC: Without preterm birth event | 66 | 38 |
| HIC: With preterm birth event | 9 | 4 |
| HIC: Without preterm birth event | 178 | 88 |
Collected over Maternal groups: All-cause mortality, AESIs, and SAEs: From conception to Day 42 post-delivery of any pregnancy. Infant groups: All-cause mortality, AESIs, and SAEs: From birth to Day 42 post-birth of any pregnancy.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| RSV MAT Group - Mother | 0/296 (0%) | 60/296 (20.3%) | 145/296 (49%) |
| Control Group - Mother | 0/152 (0%) | 37/152 (24.3%) | 65/152 (42.8%) |
| RSV MAT Group - Infant | 1/275 (0.4%) | 39/275 (14.2%) | 76/275 (27.6%) |
| Control Group - Infant | 0/136 (0%) | 17/136 (12.5%) | 42/136 (30.9%) |
| Event | RSV MAT Group - Mother | Control Group - Mother | RSV MAT Group - Infant | Control Group - Infant |
|---|---|---|---|---|
| Abortion spontaneousPregnancy, puerperium and perinatal conditions | 28/296 | 14/152 | 0/275 | 0/136 |
| Premature babyPregnancy, puerperium and perinatal conditions | 0/296 | 0/152 | 10/275 | 3/136 |
| Tethered oral tissueCongenital, familial and genetic disorders | 0/296 | 0/152 | 0/275 | 3/136 |
| Low birth weight babyPregnancy, puerperium and perinatal conditions | 0/296 | 0/152 | 6/275 | 3/136 |
| Neonatal asphyxiaRespiratory, thoracic and mediastinal disorders | 0/296 | 0/152 | 0/275 | 3/136 |
| Neonatal respiratory distress syndromeRespiratory, thoracic and mediastinal disorders | 0/296 | 0/152 | 6/275 | 1/136 |
| Postpartum haemorrhagePregnancy, puerperium and perinatal conditions | 1/296 | 3/152 | 0/275 | 0/136 |
| Pre-eclampsiaPregnancy, puerperium and perinatal conditions | 4/296 | 3/152 | 0/275 | 0/136 |
| Transient tachypnoea of the newbornRespiratory, thoracic and mediastinal disorders | 0/296 | 0/152 | 2/275 | 2/136 |
| Threatened labourPregnancy, puerperium and perinatal conditions | 4/296 | 1/152 | 0/275 | 0/136 |
| Event | RSV MAT Group - Mother | Control Group - Mother | RSV MAT Group - Infant | Control Group - Infant |
|---|---|---|---|---|
| Small for dates babyPregnancy, puerperium and perinatal conditions | 0/296 | 0/152 | 19/275 | 13/136 |
| AnaemiaBlood and lymphatic system disorders | 15/296 | 13/152 | 1/275 | 0/136 |
| Urinary tract infectionInfections and infestations | 18/296 | 6/152 | 0/275 | 0/136 |
| Low birth weight babyPregnancy, puerperium and perinatal conditions | 0/296 | 0/152 | 15/275 | 4/136 |
| NauseaGastrointestinal disorders | 16/296 | 6/152 | 0/275 | 0/136 |
| Gestational diabetesPregnancy, puerperium and perinatal conditions | 13/296 | 8/152 | 0/275 | 0/136 |
| Premature babyPregnancy, puerperium and perinatal conditions | 0/296 | 0/152 | 14/275 | 5/136 |
| Perineal injuryInjury, poisoning and procedural complications | 15/296 | 4/152 | 0/275 | 0/136 |
| Tethered oral tissueCongenital, familial and genetic disorders | 0/296 | 0/152 | 4/275 | 6/136 |
| Premature labourPregnancy, puerperium and perinatal conditions | 12/296 | 3/152 | 0/275 | 0/136 |
| Age, Customized(Participants) | RSV MAT Group - Mother | Control Group - Mother | RSV MAT Group - Infant | Control Group - Infant | Total |
|---|---|---|---|---|---|
| 0 to 1 years of age | 0 | 0 | 275 | 136 | 411 |
| <18 years of age | 2 | 0 | 0 | 0 | 2 |
| 18 to 24 years of age | 76 | 29 | 0 | 0 | 105 |
| 25 to 34 years of age | 181 | 97 | 0 | 0 | 278 |
| >=35 years of age | 37 | 26 | 0 | 0 | 63 |
| Sex: Female, Male(Participants) | RSV MAT Group - Mother | Control Group - Mother | RSV MAT Group - Infant | Control Group - Infant | Total |
|---|---|---|---|---|---|
| Female | 296 | 152 | 144 | 65 | 657 |
| Male | 0 | 0 | 131 | 71 | 202 |
| Race/Ethnicity, Customized(Participants) | RSV MAT Group - Mother | Control Group - Mother | RSV MAT Group - Infant | Control Group - Infant | Total |
|---|---|---|---|---|---|
| American Indian Or Alaska Native | 6 | 9 | 5 | 6 | 26 |
| Asian | 41 | 22 | 39 | 19 | 121 |
| Black Or African American | 17 | 9 | 14 | 6 | 46 |
| Multiple | 16 | 6 | 19 | 8 | 49 |
| Native Hawaiian Or Other Pacific Islander | 3 | 1 | 3 | 0 | 7 |
| Not Reported | 2 | 1 | 3 | 1 | 7 |
| Unknown, Not Specified | 12 | 2 | 13 | 4 | 31 |
| White | 199 | 102 | 179 | 92 | 572 |
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Supporting information: Study protocol, Sap, Icf, Csr
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