Mixed bivalent then 9‑valent HPV vaccination schedule for girls aged 9–14.
Immunogenicity and Safety of Sequential Bivalent and 9-Valent Human Papillomavirus Vaccine Immunization in Girls Aged 9-14 Years
This study will test whether different sequences of bivalent and 9‑valent HPV vaccines produce strong antibody responses and are safe in girls aged 9–14 years.
Quick facts
| Phase | Phase 4 |
|---|---|
| Study type | Interventional |
| Enrollment | 400 (estimated) |
| Ages | 9 Years to 14 Years |
| Sex | Female |
| Sponsor | Zhejiang Provincial Center for Disease Control and Prevention Government |
| Locations | 1 site (Lishui, Zhejiang) |
| Trial ID | NCT07281677 on ClinicalTrials.gov |
What this trial studies
This Phase 4, post‑marketing randomized study in Zhejiang Province will enroll 300 healthy girls aged 9–14 and randomize them 1:1:1 to two experimental mixed‑vaccine sequences or to a two‑dose 9‑valent control schedule. Experimental Group A receives one bivalent dose followed six months later by two 9‑valent doses, Experimental Group B receives one bivalent dose followed six months later by a single 9‑valent dose, and the control group receives two 9‑valent doses six months apart. An external cohort of 100 girls will receive two doses of the bivalent vaccine as an additional comparison group. Venous blood samples will be collected at baseline, around each 9‑valent dose, and at 12 and 24 months after full immunization to measure vaccine‑type neutralizing antibodies and monitor safety.
Who should consider this trial
Good fit: Girls aged 9–14 who have never received any HPV vaccine, live at the study site, and can complete all scheduled blood draws and follow‑up visits are ideal candidates.
Not a fit: Girls who have already received any HPV vaccine, have HIV or other immunocompromising conditions, or have contraindications to intramuscular injection are unlikely to benefit from participation.
Why it matters
Potential benefit: If successful, this could show that mixed bivalent→9‑valent vaccination schedules are safe and generate robust antibody responses, allowing more flexible vaccination options for girls.
How similar studies have performed: Previous clinical and post‑marketing work has shown that switching between HPV vaccine formulations can produce comparable immune responses, so this approach has some supporting evidence.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria * Have not received any HPV vaccine products. * Girls aged 9 to 14 years. * Reside permanently at the research site. Both the participant and her legal guardian have voluntarily agreed to participate, have signed the informed consent form, understand and agree to comply with the study protocol, and are able to complete all scheduled blood collections and follow-up visits. Exclusion Criteria * Suspected or confirmed fever (≥38.5°C) within 72 hours prior to enrollment, or axillary temperature \>37.0°C on the day of enrollment. * HIV infection or other immunocompromising conditions. * Presence of acute illness or being in the acute phase of a chronic disease. * History of severe allergic reactions to any component of the study vaccine or to previous vaccinations. * Contraindications to intramuscular injection, such as thrombocytopenia, coagulation disorders, or current anticoagulant therapy. * Receipt of non-live vaccines within 14 days or live attenuated vaccines within 28 days prior to HPV vaccination in this study. * Receipt of blood or blood-derived products within 3 months prior to enrollment, or planned use within 6 months from the first vaccination to completion of the full vaccination schedule. * Any disease or condition deemed by the investigator to place the participant at unacceptable risk, prevent adherence to study requirements, or interfere with the assessment of vaccine responses.
Where this trial is running
Lishui, Zhejiang
- Jinyun center for Disease Control and Prevention — Lishui, Zhejiang, China (Recruiting)
Study contacts
- Principal investigator: Shenyu Wang — Zhejiang Provincial Center for Disease Control and Prevention
- Study coordinator: Shenyu Wang
- Email: sywang@cdc.zj.cn
- Phone: 0571-87115152
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.