Influenza Vaccine (Split Virion), Inactivated, Quadrivalent in Pregnant Women

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

Influenza Vaccine (Split Virion), Inactivated, Quadrivalent in Pregnant Women (NCT07211152) is a Phase 3 interventional studying Influenza, sponsored by Sinovac Biotech Co., Ltd. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

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.

What Stage of Research Is This?

Phase 3 trials confirm efficacy and safety in large patient groups (often 300–3,000+) and form the evidence base for an FDA approval submission. For Influenza, Phase 3 studies typically randomize participants between the investigational treatment and either a placebo or current standard of care. A successful Phase 3 result is the threshold most treatments need to clear before regulatory approval.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

Target enrollment of 150 participants puts this in the typical range for a Phase 2-style efficacy study or a moderate Phase 3 trial in a focused Influenza subpopulation. At this scale, the study has enough statistical power to detect a clear treatment effect but is not the largest cohort in the field.

Who May Be Eligible (Plain English)

Who May Qualify: 1. Pregnant women aged 18 to 39 years in good health or medically stable. 2. Gestational age of 20 to 32 weeks, based on last menstrual period, early or late ultrasound dating. 3. The participant was tested negative for HIV, Syphilis, Hepatitis B, Hepatitis C infection according to medical records or rapid tests. 4. Participants should provide verifiable identification. 5. Participants are able to understand and sign the willing to sign a consent form form voluntarily; 6. Participants are willing and able to adhere to visit schedules and all study requirements. Who Should NOT Join This Trial: 1. Receipt of any seasonal influenza vaccine within 6 months prior to enrollment, or plans to receive other influenza vaccines during the study; 2. Participants with previous or concurrent dangerous pregnancy complications such as gestational diabetes mellitus (GDM), pregnant induced hypertension, preeclampsia and known uterine anomaly; 3. History of preterm delivery, or spontaneous abortion; 4. Known fetal congenital anomaly, e.g. genetic abnormality or major congenital malformation based on antenatal ultrasound; 5. Signs or symptoms of active preterm labor, defined as regular uterine contractions with cervical change (dilation/effacement); 6. History of Guillain-Barré syndrome within 6 weeks of a prior dose of any influenza vaccine; 7. Received any vaccine in the 4 weeks prior to study vaccination, or plans to receive any vaccine within 4 weeks after study vaccination; 8. Serious allergic reaction or other serious adverse reaction to any influenza vaccines or their components; ...See full criteria on ClinicalTrials.gov Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

Inclusion Criteria: 1. Pregnant women aged 18 to 39 years in good health or medically stable. 2. Gestational age of 20 to 32 weeks, based on last menstrual period, early or late ultrasound dating. 3. The participant was tested negative for HIV, Syphilis, Hepatitis B, Hepatitis C infection according to medical records or rapid tests. 4. Participants should provide verifiable identification. 5. Participants are able to understand and sign the informed consent form voluntarily; 6. Participants are willing and able to adhere to visit schedules and all study requirements. Exclusion Criteria: 1. Receipt of any seasonal influenza vaccine within 6 months prior to enrollment, or plans to receive other influenza vaccines during the study; 2. Participants with previous or concurrent dangerous pregnancy complications such as gestational diabetes mellitus (GDM), pregnant induced hypertension, preeclampsia and known uterine anomaly; 3. History of preterm delivery, or spontaneous abortion; 4. Known fetal congenital anomaly, e.g. genetic abnormality or major congenital malformation based on antenatal ultrasound; 5. Signs or symptoms of active preterm labor, defined as regular uterine contractions with cervical change (dilation/effacement); 6. History of Guillain-Barré syndrome within 6 weeks of a prior dose of any influenza vaccine; 7. Received any vaccine in the 4 weeks prior to study vaccination, or plans to receive any vaccine within 4 weeks after study vaccination; 8. Serious allergic reaction or other serious adverse reaction to any influenza vaccines or their components; 9. 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; 10. Diagnosed abnormal coagulation function (e.g., coagulation factor deficiency, coagulation disorders, or platelet abnormalities), or obvious bruising following venipuncture; 11. 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); 12. Current or history of severe neurological diseases (such as epilepsy, convulsions or seizures) or psychiatric disorders, or family history of psychiatric disorders; 13. Acute diseases or acute stage of chronic diseases within 7 days prior to vaccination; 14. Receipt of blood, blood-derived products or immunoglobulins within 3 months prior to vaccination or plans for such treatment in the study; 15. Alcoholism or history of drug abuse; 16. Receipt of other investigational drugs/vaccines within 30 days prior to enrollment, or plan to receive investigational drugs/vaccines during the study period; 17. Fever on vaccination day, with axillary temperature ≥ 37.3°C pre-vaccination; 18. Any other factors which are unsuitable for participation in the clinical trial as judged by the investigator.

Treatments Being Tested

BIOLOGICAL

Participants will receive one dose of vaccine (0.5 mL) of Sinovac QIV

BIOLOGICAL

Vaxigrip QIV

Participants will receive one dose of vaccine (0.5 mL) of Vaxigrip QIV

Locations (2)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

Health Cube Medical Clinics

Mandaluyong, National Capital Region, Philippines

University of the Philippines - Philippine General Hospital (UP-PGH)

Manila, National Capital Region, Philippines

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT07211152), the sponsor (Sinovac Biotech Co., Ltd), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT07211152 clinical trial studying?

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 full protocol is registered on ClinicalTrials.gov and includes the primary outcome measures, eligibility criteria, and study endpoints.

Who can participate in NCT07211152?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT07211152?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT07211152. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT07211152. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-05-08 · Data from ClinicalTrials.gov.