InfluenzaPhase 3NCT07211152
Influenza Vaccine (Split Virion), Inactivated, Quadrivalent in Pregnant Women
A Phase 3 study testing Participants will receive one dose of vaccine (0.5 mL) of Sinovac QIV and Vaxigrip QIV in people with Influenza, run by Sinovac Biotech Co., Ltd at 2 sites in Philippines.
Trial summary
This is a randomized, double-blind, positive controlled phase Ⅲ clinical trial to assess the immunogenicity and safety of Sinovac QIV in pregnant women. A total of 150 healthy pregnant women aged 18~39 years at 20 to 32 weeks of pregnancy will be enrolled. Read more about this study
- Who is it for?
- Ages 18 to 39 years, women onlyHealthy volunteers can take part
- Conditions the study is for
- Influenza
- What is being tested?
- Participants will receive one dose of vaccine (0.5 mL) of Sinovac QIV and Vaxigrip QIV
- Type of treatment
- Vaccines
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 150 participants
- Where
- 2 sitesPhilippines
- Study dates
- 7 Apr 2025to 26 Jun 2026
- Phase
- Phase 3
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 39 years
- Women only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Pregnant women aged 18 to 39 years in good health or medically stable.
- Gestational age of 20 to 32 weeks, based on last menstrual period, early or late ultrasound dating.
- The participant was tested negative for HIV, Syphilis, Hepatitis B, Hepatitis C infection according to medical records or rapid tests.
- Participants should provide verifiable identification.
- Participants are able to understand and sign the informed consent form voluntarily;
- Participants are willing and able to adhere to visit schedules and all study requirements.
Who cannot join
- Receipt of any seasonal influenza vaccine within 6 months prior to enrollment, or plans to receive other influenza vaccines during the study;
- Participants with previous or concurrent dangerous pregnancy complications such as gestational diabetes mellitus (GDM), pregnant induced hypertension, preeclampsia and known uterine anomaly;
- History of preterm delivery, or spontaneous abortion;
- Known fetal congenital anomaly, e.g. genetic abnormality or major congenital malformation based on antenatal ultrasound;
- Signs or symptoms of active preterm labor, defined as regular uterine contractions with cervical change (dilation/effacement);
- History of Guillain-Barré syndrome within 6 weeks of a prior dose of any influenza vaccine;
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- Received any vaccine in the 4 weeks prior to study vaccination, or plans to receive any vaccine within 4 weeks after study vaccination;
- Serious allergic reaction or other serious adverse reaction to any influenza vaccines or their components;
- Autoimmune diseases, immunodeficiency, any immunosuppressant within 6 months prior to vaccination (≥ 20mg/day prednisone or equivalent, but corticosteroid spray therapy for allergic rhinitis and surface corticosteroid therapy for acute non-concurrent dermatitis are permitted) or cytotoxic therapy, or plans for such treatment during the study;
- Diagnosed abnormal coagulation function (e.g., coagulation factor deficiency, coagulation disorders, or platelet abnormalities), or obvious bruising following venipuncture;
- Significant chronic diseases that, in the judgement of the investigator, might interfere with the study (may include, but are not limited to cardiovascular disease, liver or kidney disorders, HIV infection or malignant tumor);
- Current or history of severe neurological diseases (such as epilepsy, convulsions or seizures) or psychiatric disorders, or family history of psychiatric disorders;
- Acute diseases or acute stage of chronic diseases within 7 days prior to vaccination;
- Receipt of blood, blood-derived products or immunoglobulins within 3 months prior to vaccination or plans for such treatment in the study;
- Alcoholism or history of drug abuse;
- Receipt of other investigational drugs/vaccines within 30 days prior to enrollment, or plan to receive investigational drugs/vaccines during the study period;
- Fever on vaccination day, with axillary temperature ≥ 37.3°C pre-vaccination;
- Any other factors which are unsuitable for participation in the clinical trial as judged by the investigator.
Trial locations and contacts
2 sites in 1 country.
Philippines2 sites
Health Cube Medical Clinics
Mandaluyong, National Capital Region
University of the Philippines - Philippine General Hospital (UP-PGH)
Manila, National Capital Region
About this study
Official title: A Phase Ⅲ, Randomized, Double-blind, Positive Controlled Clinical Trial to Evaluate the Immunogenicity and Safety of an Influenza Vaccine (Split Virion), Inactivated, Quadrivalent in Pregnant Women
This is a randomized, double-blind, positive controlled phase Ⅲ clinical trial to assess the immunogenicity and safety of Sinovac QIV in pregnant women. A total of 150 healthy pregnant women aged 18~39 years at 20 to 32 weeks of pregnancy will be enrolled. All participants will be randomized to test group and control group in a ratio of 2:1 and receive one dose of vaccine (0.5 mL) of Sinovac QIV or Vaxigrip QIV, respectively.
Blood samples will be collected from participants prior to vaccination and 28 days after vaccination. Moreover, to evaluate trans-placental antibodies, blood samples at the end of the gestation period (delivery) and the cord blood sample will be collected, if applicable.
For safety assessment, any immediate adverse events within 30 minutes, solicited local and systemic adverse events within 7 days and unsolicited adverse events within 28 days will be collected. Serious adverse events will be collected within 8 weeks after delivery. Pregnancy and birth outcomes will be collected as well.
Read the detailed description
This is a randomized, double-blind, positive controlled phase Ⅲ clinical trial to assess the immunogenicity and safety of Sinovac QIV in pregnant women. A total of 150 healthy pregnant women aged 18~39 years at 20 to 32 weeks of pregnancy will be enrolled. Written informed consent form (ICF) will be obtained from participants before enrollment. All participants will be randomized to test group and control group in a ratio of 2:1 and receive one dose of vaccine (0.5 mL) of Sinovac QIV or Vaxigrip QIV, respectively.
For immunogenicity assessment, blood samples will be collected from participants prior to vaccination and 28 days after vaccination. Moreover, to evaluate trans-placental antibodies, blood samples at the end of the gestation period (delivery) and the cord blood sample will be collected, if applicable.
For safety assessment, any immediate adverse events within 30 minutes after vaccine administration, solicited local and systemic adverse events within 7 days and unsolicited adverse events within 28 days will be collected. Serious adverse events will be collected within 8 weeks after delivery. Pregnancy and birth outcomes will be collected by medical record review from enrollment through hospital discharge following delivery.
- Conditions
- Influenza
- Being tested
- Participants will receive one dose of vaccine (0.5 mL) of Sinovac QIV, Vaxigrip QIV
- Keywords
- pregnant women
- Medical subject headings
- Influenza, Human
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Participants will receive one dose of vaccine (0.5 mL) of Sinovac QIVBiological
Participants will receive one dose of vaccine (0.5 mL) of Sinovac QIV
Vaxigrip QIVBiological
Participants will receive one dose of vaccine (0.5 mL) of Vaxigrip QIV
| Study group | Role | What they receive |
|---|---|---|
| Test Group | Experimental | Participants will receive one dose of vaccine (0.5 mL) of Sinovac QIV Receives: Biological: Participants will receive one dose of vaccine (0.5 mL) of Sinovac QIV |
| Control Group | Active comparator | Participants will receive one dose of vaccine (0.5 mL) of Vaxigrip QIV Receives: Biological: Vaxigrip QIV |
What is being measured
The primary outcome is the main question the study is designed to answer.
The seroconversion rates (SCRs) of hemagglutination inhibition (HI) antibodies against each antigen 28 days after vaccination.
SCR 28 days after vaccination.
Measured: 28 days after vaccination
The seroprotection rates (SPRs) of hemagglutination inhibition (HI) antibodies against each antigen 28 days after vaccination.
SPR 28 days after vaccination.
Measured: 28 days after vaccination
The geometric mean titers (GMTs) of hemagglutination inhibition (HI) antibodies against each antigen 28 days after vaccination.
GMT 28 days after vaccination.
Measured: 28 days after vaccination
The geometric mean increase (GMI) of hemagglutination inhibition (HI) antibodies against each antigen 28 days after vaccination.
GMI 28 days after vaccination.
Measured: 28 days after vaccination
Incidence of adverse reactions within 28 days after vaccination
Incidence of adverse reactions within 28 days after vaccination
Measured: 28 days after vaccination
Secondary outcomes (9)
The maternal seroconversion rates (SCRs) of HI antibodies against each antigen at the end of gestation period
SCRs at the end of gestation period
Measured: at the end of gestation period (date of delivery, estimated to be 4-17 weeks after randomization)
The maternal seroprotection rates (SPRs) of HI antibodies against each antigen at the end of gestation period
SPRs at the end of gestation period
Measured: at the end of gestation period (date of delivery, estimated to be 4-17 weeks after randomization)
The maternal geometric mean titers (GMTs) of HI antibodies against each antigen at the end of gestation period
GMTs at the end of gestation period
Measured: at the end of gestation period (date of delivery, estimated to be 4-17 weeks after randomization)
The maternal geometric mean increase (GMI) of HI antibodies against each antigen at the end of gestation period
GMI at the end of gestation period
Measured: at the end of gestation period (date of delivery, estimated to be 4-17 weeks after randomization)
The SPR of HI antibodies against each antigen in the umbilical cord blood at the end of gestation period
SPR in the umbilical cord blood at the end of gestation period
Measured: at the end of gestation period (date of delivery, estimated to be 4-17 weeks after randomization)
The GMT of HI antibodies against each antigen in the umbilical cord blood at the end of gestation period
GMT in the umbilical cord blood at the end of gestation period
Measured: at the end of gestation period (date of delivery, estimated to be 4-17 weeks after randomization)
Incidence of adverse reactions within 7 days after vaccination.
Adverse reactions within 7 days after vaccination.
Measured: 7 days after vaccination
Incidence of serious adverse events within 8 weeks after delivery.
serious adverse events within 8 weeks after delivery.
Measured: 8 weeks after delivery
Incidence of pregnancy and birth outcomes
pregnancy and birth outcomes
Measured: 8 weeks after delivery
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 Oct 2025
- Study start7 Apr 2025
- Primary completion26 Jun 2026
- Study completion26 Jun 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for InfluenzaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 150 participants (actual)
Sponsor and investigators
- Lead sponsor
- Sinovac Biotech Co., Ltd
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07211152
- Sponsor's protocol ID
- PRO-QINF-3006
- Status last verified
- Jan 2026
- First submitted
- 17 Sep 2025
- Last updated
- 23 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: De-identified individual participant data (IPD) may be shared on reasonable request.