ClinicalTrials.gg
CompletedNCT03463577Updated May 18, 2022Results posted

The Safety of Boostrix Following Routine Immunization of Pregnant Women

An observational study in Whooping Cough, sponsored by GlaxoSmithKline. Completed at 1 site in United States. Open to female participants, including healthy volunteers. Per ClinicalTrials.gov, last updated 2022-05-18.

Sponsored by GlaxoSmithKline · Observational

Study type
Observational
Model
Cohort
Time perspective
Retrospective
Enrollment
65,783
Sex
Female
01

Where this study stands

Counted across the records on this site · 2026-11-12

Among 43 studies in Whooping Cough by GlaxoSmithKline — none open to participants now, none under way, none of them phase 3. Whooping Cough · GlaxoSmithKline.

Enrollment
Largest of 11
65,783 · median 682
Started
2018
with 2 others
Observational
11 of 43
none open now
Registered
41st of 43
by date

Among the 43 studies in Whooping Cough by GlaxoSmithKline, this one has the largest enrollment of the 11 observational ones that give a count, is one of 3 that started in 2018, is one of 11 observational ones, and was the 41st registered.

Whooping Cough

290 studies on the registry are indexed under Whooping Cough; 23 are open to participants now.

Browse Whooping Cough studies →

Open to participants now

None of the 43 studies in Whooping Cough by GlaxoSmithKline is open now. The open studies under Whooping Cough, anywhere →

Who these studies take

Of the 13 Whooping Cough studies recruiting now, 2 (15%) set no upper age limit and 10 (77%) stop at 75 or younger; 9 take children under 18; 10 take healthy volunteers.

This study: female · healthy volunteers too.

The full table on the hub →

This tab as a report to print or save as PDF → With an account.

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Download CSVNarrow it in search →With an account: the 43 studies in Whooping Cough by GlaxoSmithKline as a file.
02

Study summary

The purpose of this study was to assess the safety of Boostrix administered on or after the first day of the 27th week of pregnancy by conducting a post-marketing study that provided safety information to the public and healthcare providers. This was one of the largest cohorts of pregnant women vaccinated with Boostrix in the U.S. Through partnership between Kaiser Permanente Southern California (KPSC) and the sponsor, GlaxoSmithKline (GSK), information about the safety of maternal vaccination with Boostrix and maternal and infant adverse events (AEs) in a community setting was gained.

03

Conditions studied

  • Whooping Cough

Browse trials for

Keywords

  • whooping cough, Boostrix, Tdap, safety, pregnancy, infants
04

Who can participate

Ages eligible
Child (0–17), Adult (18–64), Older adult (65+)
Sexes eligible
Female
Accepts healthy volunteers
Yes
Sampling method
Non-probability sample

Study population

Pregnant women with prenatal care and continuous membership (allowing up to a 31-day gap) at KPSC between the 1st day of the 27th week of pregnancy and the index date

Eligibility criteria

Inclusion Criteria:

  • Pregnant women with prenatal care and continuous membership (allowing up to a 31-day gap) at KPSC between the 1st day of the 27th week of pregnancy and the index (vaccination) date.
  • Exposed cohort (from the 27th week of gestation): Pregnant women vaccinated with Boostrix on or after the 1st day of the 27th week of pregnancy; who were not vaccinated with any other Tdap vaccine at any other time during the pregnancy in scope of this study.
  • Unexposed cohort: Women matched to the exposed cohort and pregnant sometime during the approximate estimated period between January 1, 2012-December 31, 2014 and did not receive any Tdap vaccine during the pregnancy in scope of this study.

For the analysis of congenital anomalies among live births, at birth and through six months of age, the following additional inclusion criteria for infants will be applied:

  • Live born
  • Born in KPSC hospitals

Note: Pregnant women vaccinated with Boostrix during pregnancy before the 27th week of gestation, with membership at the date of vaccination, and who were not vaccinated with any other Tdap vaccine at any other time during the pregnancy in scope of this study will be part of a descriptive analysis (secondary objective).

05

Study design

Observational model
Cohort
Time perspective
Retrospective
Enrollment
65,783 participants (actual)
Patient registry
No

Groups and cohorts

  • Exposed cohort women-on or after 1st day of 27th week of pregnancy

    This group consisted of pregnant women who received the Tdap vaccine (Boostrix) on or after the 1st day of the 27th week of pregnancy during the period January 1, 2018 to January 31, 2019 who were not vaccinated with any other Tdap vaccine at any other time during the pregnancy.

    Other: Safety assessment following routine immunization with Boostrix

  • Unexposed historical cohort women

    This group consisted of women matched to Exposed cohort women-on or after 1st day of 27th week of pregnancy group and pregnant at least one day during the historical period between January 1, 2012-December 31, 2014 and did not receive any Tdap vaccine during the pregnancy.

    Other: Safety assessment following routine immunization with Boostrix

  • Exposed cohort women-before 1st day of 27th week of pregnancy

    This group consisted of pregnant women who received the Tdap vaccine (Boostrix) before the 1st day of the 27th week of pregnancy during the period January 1, 2018-January 31, 2019 who were not vaccinated with any other Tdap vaccine at any other time during the pregnancy.

    Other: Safety assessment following routine immunization with Boostrix

  • Exposed cohort infants-on or after 1st day of 27th week of pregnancy

    This group consisted of infants whose mothers belong to Exposed cohort women-on or after 1st day of 27th week of pregnancy group.

    Other: Safety assessment following routine immunization with Boostrix

  • Unexposed historical cohort infants

    This group consisted of infants whose mothers belong to the Unexposed historical cohort women group.

    Other: Safety assessment following routine immunization with Boostrix

  • Exposed cohort infants-before 1st day of 27th week of pregnancy

    This group consisted of infants whose mothers belong to the Exposed cohort women-before 1st day of 27th week of pregnancy group.

    Other: Safety assessment following routine immunization with Boostrix

Interventions

  • OtherSafety assessment following routine immunization with Boostrix

    Subject-level data was collected for pregnant women and their infants through the Electronic Health Records.

06

What researchers measure

Primary outcomes

  1. Incidence Rate (Per 1000 Person-years) of Pre-specified Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort-women Groups

    The incidence rate (per 1000) of maternal adverse events was calculated as the total number of adverse events in the numerator and the total person-years at risk in the denominator. Every unexposed woman was assigned an index date that is determined by the number of days from pregnancy start to the Boostrix vaccination date of her matched exposed woman. The same number of days calculated in the exposed woman was added to the pregnancy start of the unexposed woman to identify her index date. The pre-specified maternal adverse events assessed were pre-eclampsia and eclampsia; Intra-uterine infections.

    Time frame: From date of Boostrix vaccination (Exposed cohort women-on or after 1st day of 27th week of pregnancy) or from an index date (Unexposed historical cohort women) until end of enrollment or pregnancy, whichever came first, up to 13 weeks

  2. Incidence Rate (Per 1000 Persons) of Prespecified Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Women Groups

    Incidence rate (per 1000) consisted of the total number of adverse events in the numerator and the number of persons at risk in the denominator. Every unexposed woman was assigned an index date that is determined by the number of days from pregnancy start to the Boostrix vaccination date of her matched exposed woman. The same number of days calculated in the exposed woman was added to the pregnancy start of the unexposed woman to identify her index date. The pre-specified maternal adverse event assessed was preterm delivery.

    Time frame: From date of Boostrix vaccination (Exposed cohort women-on or after 1st day of 27th week of pregnancy) or from an index date (Unexposed historical cohort women) until end of enrollment or pregnancy, whichever came first, up to 13 weeks

  3. Incidence Rate (Per 1000 Persons) of Pre-specified Infant Adverse Events for Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Infants Groups

    The incidence rate (per 1000) of adverse events was calculated as the total number of adverse events in the numerator and the total of persons at risk in the denominator. The pre-specified infant adverse event assessed was small for gestational age.

    Time frame: From birth through 6 months of age

Secondary outcomes

  1. Incidence Rate (Per 1000 Person-years) of Other Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Women Groups

    The incidence rate (per 1000) of other maternal adverse events was calculated as the total number of adverse events in the numerator and the total person-years at risk in the denominator. Every unexposed woman was assigned an index date that is determined by the number of days from pregnancy start to the Boostrix vaccination date of her matched exposed woman. The same number of days calculated in the exposed woman was added to the pregnancy start of the unexposed woman to identify her index date. The analysis was used for hypothesis generation/signal detection, hence without adjustment for multiple comparisons. The other maternal adverse events assessed were poor fetal growth; placental abruption; preterm pre-labor rupture of membranes; maternal death.

    Time frame: From date of Boostrix vaccination (Exposed cohort women-on or after 1st day of 27th week of pregnancy) or from an index date (Unexposed historical cohort women) until end of enrollment or pregnancy, whichever came first, up to 13 weeks

  2. Incidence Rate (Per 1000 Persons) of Other Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Women Groups

    The incidence rate (per 1000) consisted of the total number of adverse events in the numerator and the number of persons at risk in the denominator. Every unexposed woman was assigned an index date that is determined by the number of days from pregnancy start to the Boostrix vaccination date of her matched exposed woman. The same number of days calculated in the exposed woman was added to the pregnancy start of the unexposed woman to identify her index date. The analysis was used for hypothesis generation/signal detection, hence without adjustment for multiple comparisons. The other maternal adverse events assessed were stillbirth/fetal death; stillbirth/fetal death with congenital anomalies; transfusion during delivery hospitalization.

    Time frame: From date of Boostrix vaccination (Exposed cohort women-on or after 1st day of 27th week of pregnancy) or from an index date (Unexposed historical cohort women) until end of enrollment or pregnancy, whichever came first, up to 13 weeks

  3. Incidence Rate (Per 1000 Persons) of Other Infant Adverse Events for Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Infants Groups

    The incidence rate (per 1000) of other infant adverse events was calculated as the total number of adverse events in the numerator and the total of persons at risk in the denominator. The analysis was used for hypothesis generation/signal detection, hence without adjustment for multiple comparisons. The other infant adverse events assessed were neonatal death, congenital anomalies of: nervous system; eye; ear, face, or neck; cardiovascular system; respiratory system; clefts; upper gastrointestinal system; lower gastrointestinal system; genital organs; renal system; musculoskeletal system; limb; integument; other and unspecified.

    Time frame: From birth through 6 months of age

  4. Incidence Rate (Per 1000 Person-years) of Women Adverse Events for Exposed Cohort Women-before 1st Day of 27th Week of Pregnancy Group

    The incidence rate (per 1000) was calculated as the total number of adverse events in the numerator and the total person-years at risk in the denominator. Due to the small sample size, the analysis of these women adverse events was descriptive. The women adverse events assessed were pre-eclampsia and eclampsia; intra-uterine infections; poor fetal growth; placental abruption; preterm pre-labor rupture of membranes; maternal death.

    Time frame: For the Exposed cohort women-before 1st day of 27th week of pregnancy: from date of Boostrix vaccination until end of enrollment or pregnancy, whichever came first, up to 40 weeks

  5. Incidence Rate (Per 1000 Persons) of Women Adverse Events Presented for Exposed Cohort Women-before 1st Day of 27th Week of Pregnancy Group

    The incidence rate (per 1000) consisted of the total number of adverse events in the numerator and the number of persons at risk in the denominator. The adverse events of this analysis include the adverse events presented in the above outcomes as well as spontaneous and therapeutic abortion with or without congenital anomalies in pregnant women vaccinated with Boostrix before the 27th week of gestation. Due to the small sample size, the analysis of these women adverse events was descriptive. The women adverse events assessed were stillbirth/fetal death; stillbirth/fetal death with congenital anomalies; spontaneous abortion; spontaneous abortion with congenital anomalies; therapeutic abortion; therapeutic abortion with congenital anomalies; transfusion during delivery hospitalization; preterm delivery.

    Time frame: For the Exposed cohort women-before 1st day of 27th week of pregnancy: from date of Boostrix vaccination until end of enrollment or pregnancy, whichever came first, up to 40 weeks

  6. Incidence Rate (Per 1000 Persons) of Infant Adverse Events for Exposed Cohort Infants-before 1st Day of 27th Week of Pregnancy Group

    The incidence rate (per 1000) was calculated as the total number of adverse events in the numerator and the total of persons at risk in the denominator. The adverse events of this analysis include adverse events presented in the above outcomes, among the infants whose mothers were vaccinated with Boostrix before the 27th week of gestation. Due to the small sample size, the analysis of these infant adverse events was descriptive. The infant adverse events assessed were: small for gestational age; neonatal death; congenital anomalies of: nervous system; eye; ear, face, or neck; cardiovascular system; respiratory system; clefts; upper gastrointestinal system; lower gastrointestinal system; genital organs; renal system; musculoskeletal system; limb; integument; other and unspecified.

    Time frame: From birth through 6 months of age

07

Results

Posted May 18, 2022
Limitations and caveats
Main limitation: difference in background rates and time periods for both cohorts. Other: confounding by indication possible for a less select historical unvaccinated population. The study wasn't designed to study safety of exposure before 27 weeks of gestation and was conducted in a prepaid health plan, so findings may not be generalized to uninsured populations. Congenital anomalies analysis performed by event code without adjustment for multiple testing.

Participant flow

Data was collected for both pregnant women and their infants from Kaiser Permanente Southern California (KPSC) Electronic Health Records (EHR).

Participant flow — Overall Study
MilestoneExposed Cohort women-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort WomenExposed Cohort Women-before 1st Day of 27th Week of PregnancyExposed Cohort infants-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort InfantsExposed Cohort Infants-before 1st Day of 27th Week of Pregnancy
Started166061660665163501608868
Completed163661616665163351607168
Not completed240440015170
Withdrew: Lost to follow-up2384350000
Withdrew: With unknown pregnancy outcome050000
Withdrew: Maternal death200000
Withdrew: Neonatal death00015170

Outcome measures

PrimaryIncidence Rate (Per 1000 Person-years) of Pre-specified Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort-women Groups

The incidence rate (per 1000) of maternal adverse events was calculated as the total number of adverse events in the numerator and the total person-years at risk in the denominator. Every unexposed woman was assigned an index date that is determined by the number of days from pregnancy start to the Boostrix vaccination date of her matched exposed woman. The same number of days calculated in the exposed woman was added to the pregnancy start of the unexposed woman to identify her index date. The pre-specified maternal adverse events assessed were pre-eclampsia and eclampsia; Intra-uterine infections.

Time frame:
From date of Boostrix vaccination (Exposed cohort women-on or after 1st day of 27th week of pregnancy) or from an index date (Unexposed historical cohort women) until end of enrollment or pregnancy, whichever came first, up to 13 weeks
Reported as:
Number · Events per 1000 persons-year
Incidence Rate (Per 1000 Person-years) of Pre-specified Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort-women Groups
Events per 1000 persons-yearExposed Cohort women-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort Women
Pre-eclampsia and eclampsia316.16 (296.24 to 337.42)219.00 (202.13 to 237.28)
Intra-uterine infections292.53 (273.56 to 312.81)207.35 (191.12 to 224.95)
Statistical analysis
  • Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Women · Risk ratio (rr): 1.38 · 98.75% CI 1.21 to 1.58Adjusted relative risk with 98.75% CI was estimated by Poisson regression model
  • Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Women · Risk ratio (rr): 1.28 · 98.75% CI 1.12 to 1.47Adjusted relative risk with 98.75% CI was estimated by Poisson regression model
PrimaryIncidence Rate (Per 1000 Persons) of Prespecified Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Women Groups

Incidence rate (per 1000) consisted of the total number of adverse events in the numerator and the number of persons at risk in the denominator. Every unexposed woman was assigned an index date that is determined by the number of days from pregnancy start to the Boostrix vaccination date of her matched exposed woman. The same number of days calculated in the exposed woman was added to the pregnancy start of the unexposed woman to identify her index date. The pre-specified maternal adverse event assessed was preterm delivery.

Time frame:
From date of Boostrix vaccination (Exposed cohort women-on or after 1st day of 27th week of pregnancy) or from an index date (Unexposed historical cohort women) until end of enrollment or pregnancy, whichever came first, up to 13 weeks
Reported as:
Number · Events per 1000 persons
Incidence Rate (Per 1000 Persons) of Prespecified Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Women Groups
Events per 1000 personsExposed Cohort women-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort Women
Incidence Rate (Per 1000 Persons) of Prespecified Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Women Groups64.63 (60.90 to 68.58)92.28 (87.84 to 96.94)
Statistical analysis
  • Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Women · Risk ratio (rr): 0.71 · 98.75% CI 0.64 to 0.78Adjusted relative risk with 98.75% CI was estimated by Poisson regression model
PrimaryIncidence Rate (Per 1000 Persons) of Pre-specified Infant Adverse Events for Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Infants Groups

The incidence rate (per 1000) of adverse events was calculated as the total number of adverse events in the numerator and the total of persons at risk in the denominator. The pre-specified infant adverse event assessed was small for gestational age.

Time frame:
From birth through 6 months of age
Reported as:
Number · Events per 1000 persons
Incidence Rate (Per 1000 Persons) of Pre-specified Infant Adverse Events for Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Infants Groups
Events per 1000 personsExposed Cohort infants-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort Infants
Incidence Rate (Per 1000 Persons) of Pre-specified Infant Adverse Events for Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Infants Groups80.42 (76.30 to 84.76)75.00 (70.98 to 79.25)
Statistical analysis
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.04 · 98.75% CI 0.94 to 1.16Adjusted RR with 98.75% CI-Poisson regression model
SecondaryIncidence Rate (Per 1000 Person-years) of Other Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Women Groups

The incidence rate (per 1000) of other maternal adverse events was calculated as the total number of adverse events in the numerator and the total person-years at risk in the denominator. Every unexposed woman was assigned an index date that is determined by the number of days from pregnancy start to the Boostrix vaccination date of her matched exposed woman. The same number of days calculated in the exposed woman was added to the pregnancy start of the unexposed woman to identify her index date. The analysis was used for hypothesis generation/signal detection, hence without adjustment for multiple comparisons. The other maternal adverse events assessed were poor fetal growth; placental abruption; preterm pre-labor rupture of membranes; maternal death.

Time frame:
From date of Boostrix vaccination (Exposed cohort women-on or after 1st day of 27th week of pregnancy) or from an index date (Unexposed historical cohort women) until end of enrollment or pregnancy, whichever came first, up to 13 weeks
Reported as:
Number · Events per 1000 persons-year
Incidence Rate (Per 1000 Person-years) of Other Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Women Groups
Events per 1000 persons-yearExposed Cohort women-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort Women
Poor fetal growth116.00 (103.99 to 129.40)137.63 (124.29 to 152.40)
Placental abruption56.63 (48.45 to 66.19)44.59 (37.30 to 53.32)
Preterm pre-labor rupture of membranes115.53 (103.52 to 128.94)141.52 (127.95 to 156.53)
Maternal death0.43 (0.11 to 1.72)—
Statistical analysis
  • Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Women · Risk ratio (rr): 0.83 · 95% CI 0.70 to 0.98Adjusted RR with 95% CI -Poisson regression model
  • Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Women · Risk ratio (rr): 1.31 · 95% CI 0.99 to 1.72Adjusted RR with 95% CI - Poisson regression model
  • Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Women · Risk ratio (rr): 0.76 · 95% CI 0.64 to 0.91Adjusted RR with 95% CI-Poisson regression model
SecondaryIncidence Rate (Per 1000 Persons) of Other Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Women Groups

The incidence rate (per 1000) consisted of the total number of adverse events in the numerator and the number of persons at risk in the denominator. Every unexposed woman was assigned an index date that is determined by the number of days from pregnancy start to the Boostrix vaccination date of her matched exposed woman. The same number of days calculated in the exposed woman was added to the pregnancy start of the unexposed woman to identify her index date. The analysis was used for hypothesis generation/signal detection, hence without adjustment for multiple comparisons. The other maternal adverse events assessed were stillbirth/fetal death; stillbirth/fetal death with congenital anomalies; transfusion during delivery hospitalization.

Time frame:
From date of Boostrix vaccination (Exposed cohort women-on or after 1st day of 27th week of pregnancy) or from an index date (Unexposed historical cohort women) until end of enrollment or pregnancy, whichever came first, up to 13 weeks
Reported as:
Number · Events per 1000 persons
Incidence Rate (Per 1000 Persons) of Other Maternal Adverse Events for Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Women Groups
Events per 1000 personsExposed Cohort women-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort Women
Stillbirth/fetal death1.41 (0.93 to 2.11)2.41 (1.76 to 3.30)
Transfusion during delivery hospitalization12.79 (11.17 to 14.65)12.02 (10.43 to 13.84)
Statistical analysis
  • Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Women · Risk ratio (rr): 0.38 · 95% CI 0.22 to 0.67Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Women · Risk ratio (rr): 1.07 · 95% CI 0.86 to 1.33Adjusted RR with 95% CI-Poisson regression model
SecondaryIncidence Rate (Per 1000 Persons) of Other Infant Adverse Events for Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Infants Groups

The incidence rate (per 1000) of other infant adverse events was calculated as the total number of adverse events in the numerator and the total of persons at risk in the denominator. The analysis was used for hypothesis generation/signal detection, hence without adjustment for multiple comparisons. The other infant adverse events assessed were neonatal death, congenital anomalies of: nervous system; eye; ear, face, or neck; cardiovascular system; respiratory system; clefts; upper gastrointestinal system; lower gastrointestinal system; genital organs; renal system; musculoskeletal system; limb; integument; other and unspecified.

Time frame:
From birth through 6 months of age
Reported as:
Number · Events per 1000 persons
Incidence Rate (Per 1000 Persons) of Other Infant Adverse Events for Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy and Unexposed Historical Cohort Infants Groups
Events per 1000 personsExposed Cohort infants-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort Infants
Neonatal death0.92 (0.55 to 1.52)1.06 (0.66 to 1.70)
Congenital anomalies of nervous system2.81 (2.11 to 3.76)2.36 (1.72 to 3.25)
Congenital anomalies of eye69.85 (66.05 to 73.87)60.48 (56.91 to 64.28)
Congenital anomalies of ear, face, or neck16.27 (14.43 to 18.35)8.14 (6.86 to 9.66)
Congenital anomalies of cardiovascular system24.40 (22.15 to 26.89)21.82 (19.67 to 24.20)
Congenital anomalies of respiratory system13.76 (12.08 to 15.68)10.32 (8.86 to 12.01)
Clefts1.96 (1.38 to 2.77)1.49 (1.00 to 2.23)
Congenital anomalies of upper gastrointestinal system67.83 (64.08 to 71.79)37.85 (35.02 to 40.92)
Congenital anomalies of lower gastrointestinal system1.35 (0.89 to 2.04)2.30 (1.67 to 3.17)
Congenital anomalies of genital organs21.71 (19.57 to 24.09)18.46 (16.48 to 20.68)
Congenital anomalies of renal system7.83 (6.58 to 9.31)5.91 (4.83 to 7.22)
Congenital anomalies of musculoskeletal system16.27 (14.43 to 18.35)10.63 (9.15 to 12.35)
Congenital anomalies of limb7.09 (5.91 to 8.51)6.90 (5.73 to 8.31)
Congenital anomalies of integument58.04 (54.57 to 61.74)29.65 (27.14 to 32.39)
Other and unspecified congenital anomalies1.96 (1.38 to 2.77)2.05 (1.46 to 2.89)
Statistical analysis
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 0.81 · 95% CI 0.38 to 1.73Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.35 · 95% CI 0.81 to 2.24Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.17 · 95% CI 1.06 to 1.29Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 2.02 · 95% CI 1.59 to 2.55Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.12 · 95% CI 0.96 to 1.31Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.34 · 95% CI 1.07 to 1.68Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.41 · 95% CI 0.78 to 2.57Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.75 · 95% CI 1.57 to 1.95Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 0.63 · 95% CI 0.36 to 1.12Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.19 · 95% CI 1.01 to 1.42Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.40 · 95% CI 1.04 to 1.88Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.50 · 95% CI 1.21 to 1.86Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.13 · 95% CI 0.85 to 1.52Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.98 · 95% CI 1.76 to 2.23Adjusted RR with 95% CI-Poisson regression model
  • Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy vs Unexposed Historical Cohort Infants · Risk ratio (rr): 1.09 · 95% CI 0.64 to 1.85Adjusted RR with 95% CI-Poisson regression model
SecondaryIncidence Rate (Per 1000 Person-years) of Women Adverse Events for Exposed Cohort Women-before 1st Day of 27th Week of Pregnancy Group

The incidence rate (per 1000) was calculated as the total number of adverse events in the numerator and the total person-years at risk in the denominator. Due to the small sample size, the analysis of these women adverse events was descriptive. The women adverse events assessed were pre-eclampsia and eclampsia; intra-uterine infections; poor fetal growth; placental abruption; preterm pre-labor rupture of membranes; maternal death.

Time frame:
For the Exposed cohort women-before 1st day of 27th week of pregnancy: from date of Boostrix vaccination until end of enrollment or pregnancy, whichever came first, up to 40 weeks
Reported as:
Number · Events per 1000 persons-year
Incidence Rate (Per 1000 Person-years) of Women Adverse Events for Exposed Cohort Women-before 1st Day of 27th Week of Pregnancy Group
Events per 1000 persons-yearExposed Cohort Women-before 1st Day of 27th Week of Pregnancy
Pre-eclampsia and eclampsia354.50 (146.26 to 755.09)
Intra-uterine infections176.42 (45.85 to 525.92)
Poor fetal growth119.75 (20.81 to 453.17)
Preterm pre-labor rupture of membranes117.65 (20.45 to 445.22)
SecondaryIncidence Rate (Per 1000 Persons) of Women Adverse Events Presented for Exposed Cohort Women-before 1st Day of 27th Week of Pregnancy Group

The incidence rate (per 1000) consisted of the total number of adverse events in the numerator and the number of persons at risk in the denominator. The adverse events of this analysis include the adverse events presented in the above outcomes as well as spontaneous and therapeutic abortion with or without congenital anomalies in pregnant women vaccinated with Boostrix before the 27th week of gestation. Due to the small sample size, the analysis of these women adverse events was descriptive. The women adverse events assessed were stillbirth/fetal death; stillbirth/fetal death with congenital anomalies; spontaneous abortion; spontaneous abortion with congenital anomalies; therapeutic abortion; therapeutic abortion with congenital anomalies; transfusion during delivery hospitalization; preterm delivery.

Time frame:
For the Exposed cohort women-before 1st day of 27th week of pregnancy: from date of Boostrix vaccination until end of enrollment or pregnancy, whichever came first, up to 40 weeks
Reported as:
Number · Events per 1000 persons
Incidence Rate (Per 1000 Persons) of Women Adverse Events Presented for Exposed Cohort Women-before 1st Day of 27th Week of Pregnancy Group
Events per 1000 personsExposed Cohort Women-before 1st Day of 27th Week of Pregnancy
Spontaneous abortion15.38 (0.80 to 94.03)
Transfusion during delivery hospitalization15.63 (0.82 to 95.41)
Preterm delivery46.88 (12.18 to 139.59)
SecondaryIncidence Rate (Per 1000 Persons) of Infant Adverse Events for Exposed Cohort Infants-before 1st Day of 27th Week of Pregnancy Group

The incidence rate (per 1000) was calculated as the total number of adverse events in the numerator and the total of persons at risk in the denominator. The adverse events of this analysis include adverse events presented in the above outcomes, among the infants whose mothers were vaccinated with Boostrix before the 27th week of gestation. Due to the small sample size, the analysis of these infant adverse events was descriptive. The infant adverse events assessed were: small for gestational age; neonatal death; congenital anomalies of: nervous system; eye; ear, face, or neck; cardiovascular system; respiratory system; clefts; upper gastrointestinal system; lower gastrointestinal system; genital organs; renal system; musculoskeletal system; limb; integument; other and unspecified.

Time frame:
From birth through 6 months of age
Reported as:
Number · Events per 1000 persons
Incidence Rate (Per 1000 Persons) of Infant Adverse Events for Exposed Cohort Infants-before 1st Day of 27th Week of Pregnancy Group
Events per 1000 personsExposed Cohort Infants-before 1st Day of 27th Week of Pregnancy
Small for gestational age116.67 (52.10 to 231.77)
Congenital anomalies of eye88.24 (36.38 to 188.56)
Congenital anomalies of ear, face, or neck73.53 (27.39 to 170.21)
Congenital anomalies of cardiovascular system14.71 (0.77 to 90.12)
Congenital anomalies of upper gastrointestinal system14.71 (0.77 to 90.12)
Congenital anomalies of genital organs44.12 (11.46 to 131.90)
Congenital anomalies of renal system14.71 (0.77 to 90.12)
Congenital anomalies of musculoskeletal system14.71 (0.77 to 90.12)
Congenital anomalies of integument102.94 (45.87 to 206.51)

Adverse events

Collected over For each woman from date of Boostrix vaccination (Exposed cohort women-on or after 1st day of 27th week of pregnancy Group and Exposed cohort women-before 1st day of 27th week of pregnancy Group), and from an index date (Unexposed historical cohort women) until end of enrollment (up to 13 weeks) or pregnancy (up to 40 weeks). For infants, from birth through 6 months of age.. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Exposed Cohort women-on or After 1st Day of 27th Week of Pregnancy2/16,606 (0%)3,733/16,606 (22.5%)—
Unexposed Historical Cohort Women0/16,606 (0%)3,679/16,606 (22.2%)—
Exposed Cohort Women-before 1st Day of 27th Week of Pregnancy0/65 (0%)18/65 (27.7%)—
Exposed Cohort infants-on or After 1st Day of 27th Week of Pregnancy15/16,350 (0.1%)5,540/16,350 (33.9%)—
Unexposed Historical Cohort Infants17/16,088 (0.1%)4,211/16,088 (26.2%)—
Exposed Cohort Infants-before 1st Day of 27th Week of Pregnancy0/68 (0%)30/68 (44.1%)—
Most frequent serious events
Showing 10 of 26
Most frequent serious events
EventExposed Cohort women-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort WomenExposed Cohort Women-before 1st Day of 27th Week of PregnancyExposed Cohort infants-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort InfantsExposed Cohort Infants-before 1st Day of 27th Week of Pregnancy
Small for gestational ageGeneral disorders———1278/158921172/156267/60
Congenital anomalies of integumentGeneral disorders———949/16350477/160887/68
Preeclampsia/eclampsiaGeneral disorders874/16606588/166066/65———
Preterm deliveryGeneral disorders1019/157671435/155513/64———
Congenital anomalies of eyeGeneral disorders———1142/16350973/160886/68
Congenital anomalies of ear, face or neckGeneral disorders———266/16350131/160885/68
Congenital anomalies of upper gastrointestinal systemGeneral disorders———1109/16350609/160881/68
Intra-uterine infectionsGeneral disorders811/16606558/166063/65———
Congenital anomalies of genital organsGeneral disorders———355/16350297/160883/68
Poor fetal growthGeneral disorders320/16606368/166062/65———

Baseline characteristics

Age, Customized
Age, Customized(Participants)Exposed Cohort women-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort WomenExposed Cohort Women-before 1st Day of 27th Week of PregnancyExposed Cohort infants-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort InfantsExposed Cohort Infants-before 1st Day of 27th Week of PregnancyTotal
0-1 year00016350160886832506
13 -51 year16606166066500033277
Sex: Female, Male
Sex: Female, Male(Participants)Exposed Cohort women-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort WomenExposed Cohort Women-before 1st Day of 27th Week of PregnancyExposed Cohort infants-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort InfantsExposed Cohort Infants-before 1st Day of 27th Week of PregnancyTotal
Female166061660665795077253648988
Male000840083633216795
Race/Ethnicity, Customized
Race/Ethnicity, Customized(Participants)Exposed Cohort women-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort WomenExposed Cohort Women-before 1st Day of 27th Week of PregnancyExposed Cohort infants-on or After 1st Day of 27th Week of PregnancyUnexposed Historical Cohort InfantsExposed Cohort Infants-before 1st Day of 27th Week of PregnancyTotal
White29742974140005962
Black1274127450002553
Hispanic968996893100019409
Asian21442144100004298
Other-Unspecified525525516350160886833561
08

Study locations

1 site
  • GSK Investigational Site
    Pasadena, California 91101, United States
09

References and documents

Study documents

PDFs hosted by the registry, ClinicalTrials.gov.

Individual participant data

Plan to share: No

10

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Ran from Apr 2018 to primary completion in Aug 2020, 27 months.

Results were first posted in May 2022, 1 year 9 months after primary completion.

How these figures are worked out, and which studies are left out of them.

Registered
Mar 6, 2018
First posted
Mar 13, 2018
StartActual
Apr 13, 2018
Primary completionActual
Aug 4, 2020
CompletionActual
Aug 4, 2020
Results first posted
May 18, 2022
Last update
May 18, 2022
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on May 18, 2022, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT03463577
Lead sponsor
GlaxoSmithKline
Collaborators
Kaiser Permanente
Responsible party
Sponsor
First posted
Mar 13, 2018
Start date
Apr 13, 2018
Primary completion
Aug 4, 2020
Completion
Aug 4, 2020
Results posted
May 18, 2022
Last update
May 18, 2022

Study contacts

GSK Clinical Trials
study director · GlaxoSmithKline

Oversight

FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in May 2022. You cannot join it, but the record below documents what was studied.

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