A Phase 3 interventional study of dTpa in Diphtheria-Tetanus-acellular Pertussis Vaccines, sponsored by GlaxoSmithKline. Active, not recruiting at 21 sites in Japan. Open to female participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-08.
Sponsored by GlaxoSmithKline · Phase 3, Interventional, and Prevention
The purpose of this Phase 3, non-randomized, single-arm, open-label study is to evaluate the immune response, reactogenicity and safety of GSKs dTpa vaccine in Japanese pregnant women between 27 weeks and less than 37 weeks of pregnancy. Both the pregnant women and their neonates born during the study will be evaluated for specific analyses.
267 studies on the registry are indexed under Diphtheria; 17 are open to participants now.
This study's enrollment of 102 is below the median of 448 across 241 interventional studies indexed under Diphtheria.
Browse Diphtheria studies →GlaxoSmithKline is the lead sponsor of 3,650 studies on the registry; 118 are open to participants now.
Of its 264 completed or terminated interventional studies of FDA-regulated products, 241 (91%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Medical conditions:
Women with co-morbid medical or obstetric conditions that in the opinion of the investigator have the potential to complicate the pregnancy course and outcomes such as;
Lymphoproliferative disorder or within 5 years before the study dose administration (excluding effectively treated non melanoma skin cancer).
Prior/Concomitant therapy:
Chronic administration of immune-modifying drugs (defined as more than 14 consecutive days in total) and/or planned use of long-acting immune-modifying treatments or planned administration through delivery.
For , this will mean prednisone equivalent >=20 mg/day for adult participants. Inhaled, intra-articular/intra-bursal and topical steroids are allowed.
long-acting immune-modifying drugs including among others immunotherapy monoclonal antibodies, antitumoral medication.
Planned administration/administration of a vaccine not foreseen by the study protocol in the period starting 30 days before the dose and planned administration through delivery (Visit 3/Day of delivery), except:
Planned administration of any prophylactic medication (e.g., analgesics, antipyretics) in the absence of any symptom and in anticipation of a reaction to the study intervention administration.
Prior/Concurrent clinical study participation:
Concurrently participating in another clinical study, at any time during the study period, in which the participant has been or will be exposed to an investigational or a non-investigational intervention drug/vaccine/invasive medical device.
Other exclusion criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Healthy pregnant women at 27 to 36 weeks of gestation receive one dose of the investigational dTpa vaccine at Day 1 (representing the day of vaccination).
Biological: dTpa
1 dose of dTpa vaccine is administered intramuscularly.
Also known as: Boostrix
Number of seropositive healthy pregnant women for anti-pertussis toxin (PT), anti-filamentous hemagglutinin (FHA) and anti-pertactin (PRN) antibodies
Seropositivity is defined as antibody concentrations (anti-PT, anti-FHA and anti-PRN) are greater than or equal to the assessed assay cut-offs. The considered cut-off values are: anti-PT: 2.693 International Units per milliliter (IU/mL), anti-FHA: 2.046 IU/mL, anti-PRN: 2.187 IU/mL, as measured by Enzyme-Linked Immunosorbent assay (ELISA).
Time frame: At Month 1 post-vaccination
Number of seropositive participants for anti-PT, anti-FHA and anti-PRN antibodies from samples in cord blood sample at birth
Time frame: On the Day of birth
Booster response to pertussis (PT, FHA and PRN) antigens in healthy pregnant women
Booster response to PT, FHA and PRN antigens is defined as: for participants with pre-vaccination antibody concentration below the assay cut-off, post-vaccination antibody concentration \>=4 times the assay cut-off; for participants with pre-vaccination antibody concentration between the assay cut-off and below 4 times the assay cut-off, post-vaccination antibody concentration \>= 4 times the pre-vaccination antibody concentration; for participants with pre-vaccination antibody concentration \>=4 times the assay cut-off, post-vaccination antibody concentration \>=2 times the pre-vaccination antibody concentration.
Time frame: At Month 1
Antibody concentration for antibodies against pertussis (PT, FHA, PRN) in healthy pregnant women
Time frame: On Day 1 (day of vaccination) and at Month 1 post-vaccination
Antibody concentration for anti-diphtheria and anti-tetanus antibodies in healthy pregnant women
Time frame: On Day 1 (day of vaccination) and at Month 1 post-vaccination
Number of seroprotected healthy pregnant women for anti-diphtheria and anti-tetanus antibodies
Seroprotection is defined as antibody concentrations (anti-diphtheria and anti-tetanus) are greater than or equal to 0.1 IU/mL by ELISA test.
Time frame: On Day 1 (day of vaccination) and at Month 1 post-vaccination
Antibody concentration for antibodies against pertussis (PT, FHA, PRN) in the cord blood of the neonates born to mothers that received dTpa vaccine during pregnancy
Time frame: On the Day of birth
Antibody concentration for anti-diphtheria and anti-tetanus antibodies in cord blood of the neonates born to mothers that received dTpa vaccine during pregnancy
Time frame: On the Day of birth
Number of seroprotected neonates for anti-diphtheria and anti-tetanus antibodies, from samples in cord blood
Time frame: On the Day of birth
Number of healthy pregnant women with solicited administration site adverse events
The assessed events are pain, redness and swelling.
Time frame: From Day 1 (day of vaccination) to Day 7 post-vaccination
Number of healthy pregnant women with solicited systemic adverse events (AEs)
The assessed events are arthralgia, gastrointestinal symptoms, fatigue, fever, headache and myalgia. Fever is defined as temperature \>=37.5 degrees Celsius.
Time frame: From Day 1 (day of vaccination) to Day 7 post-vaccination
Number of healthy pregnant women with unsolicited adverse events
An unsolicited AE is an AE that was either not included in the list of solicited AEs or could be included in the list of solicited AEs but with an onset outside the specified period of follow-up for solicited AEs. Unsolicited AEs include both serious and non-serious AEs.
Time frame: From Day 1 (day of vaccination) to Day 30 post-vaccination
Number of healthy pregnant women with serious adverse events (SAEs)
An SAE is defined as any untoward medical occurrence that, at any dose, results in death, is life threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect in the offspring of a study participant, abnormal pregnancy outcomes, is a suspected transmission of any infectious agent via an authorized medicinal product, or other situations as per investigator's judgment.
Time frame: From Day 1 (day of vaccination) and up to 1-month post-delivery (study end)
Number of healthy pregnant women with AEs and SAEs leading to study withdrawal
Time frame: From the Day 1 (day of vaccination) and up to 1-month post-delivery (study end)
Number of healthy pregnant women with pregnancy outcomes at delivery
The assessed pregnancy outcomes are: live birth with congenital anomalies, still birth with no congenital anomalies, still birth with congenital anomalies, elective termination with no congenital anomalies, elective termination with congenital anomalies.
Time frame: On the Day of delivery
Number of healthy pregnant women with pregnancy-related AEs
The assessed pregnancy-related AEs are (but not limited to): gestational diabetes, pregnancy-related hypertension, pre-eclampsia, eclampsia, premature rupture of membranes, preterm premature rupture of membranes, premature labor, threatened premature labor, fetal growth restriction, obstetrical hemorrhage, maternal death.
Time frame: From Day 1 (day of vaccination) and up to 1-month post-delivery
Number of neonates, born to mothers that received dTpa vaccine during pregnancy, with neonatal AEs
The assessed neonatal AEs are (but not limited to): preterm birth, neonatal death, small for gestational age, neonatal hypoxic ischemic encephalopathy, failure to thrive/growth deficiency.
Time frame: From the Day of birth and up to 1-month post-birth
Number of neonates, born to mothers that received dTpa vaccine during pregnancy, participants with SAEs
Time frame: From the Day of birth and up to 1-month post-birth
Number of neonates, born to mothers that received dTpa vaccine during pregnancy, with AEs and SAEs leading to study withdrawal
Time frame: From the Day of birth and up to 1-month post-birth
Plan to share: Yes — Study Sponsor will assess requests from qualified researchers for anonymized individual patient-level data and related study documents. Data sharing is subject to certain criteria, conditions, and exceptions. For further information, refer to https://www.gsk-studyregister.com/gsk-patient-level-data-sharing-july2025.pdf
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Clinical study report
Time frame: Anonymized IPD will be made available within 6 months of publication of primary, key secondary and safety results for studies in product with approved indication(s) or asset(s) with development terminated across all indications.
Access criteria: Anonymized IPD is shared with researchers whose proposals are approved by an Independent Review Panel and after a Data Sharing Agreement is in place. Access is provided for an initial period of 12 months, but an extension may be granted, when justified, for up to 6 months.
Data sharing details ↗ · www.gsk-studyregister.com
No publications or documents are linked to this record.
Started Jun 2026 (actual). Primary completion is estimated for Nov 2026, 4 months after the start.
Of 46 industry-sponsored phase 3 interventional studies under Diphtheria, half reached primary completion within 13 months of starting (the median), counting those still running; a quarter within 7 and three quarters within 21. This study's planned 4 months is below that.
Counting every sponsor, half of 46 studies reached it within 13 months; a quarter within 7 and three quarters within 21.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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