Long-term Immune Persistence of a Bivalent HPV Vaccine in Females From Study 311-HPV-1004

NCT07820241 | Active Not Recruiting

• 1 other identifier: 311-HPV-1004-EXTEND
• Study Type: observational
• Target: 348
• Locations: 1 country
• Sites: 2

Brief Summary

This long-term extension study evaluates the persistence of neutralizing antibody responses to a bivalent human papillomavirus vaccine in females who previously participated in study 311-HPV-1004 (NCT02740777). Participants belonged to one of three vaccination cohorts in the base study: adolescents who received two doses at Months 0 and 6, adolescents who received three doses at Months 0, 2, and 6, and adults who received three doses at Months 0, 2, and 6. No vaccine is administered in the extension study. Blood samples are collected at Months 84, 108, and 132 after the first dose in the base study and tested for HPV-16 and HPV-18 neutralizing antibodies using a high-throughput pseudovirus-based neutralization assay.

Conditions

Human Papillomavirus Infection

Keywords

Bivalent HPV vaccine; Immune persistence; Neutralizing antibody; Two-dose vaccination schedule; Long-term follow-up; Pichia pastoris

Outcome Measures

Primary Outcomes (4)

• Geometric Mean Titer of HPV-16 Neutralizing Antibodies

  The geometric mean and two-sided 95% confidence interval of HPV-16 neutralizing antibody titers are summarized separately for each prior-vaccination cohort using the high-throughput pseudovirus-based neutralization assay.

  Months 84, 108, and 132 after the first dose in the base study

• Geometric Mean Titer of HPV-18 Neutralizing Antibodies

  The geometric mean and two-sided 95% confidence interval of HPV-18 neutralizing antibody titers are summarized separately for each prior-vaccination cohort using the high-throughput pseudovirus-based neutralization assay.

  Months 84, 108, and 132 after the first dose in the base study

• Seropositivity Rate for HPV-16 Neutralizing Antibodies

  The percentage of participants meeting the assay-defined seropositivity threshold for HPV-16 neutralizing antibodies and its exact two-sided 95% confidence interval are summarized separately for each prior-vaccination cohort.

  Months 84, 108, and 132 after the first dose in the base study

• Seropositivity Rate for HPV-18 Neutralizing Antibodies

  The percentage of participants meeting the assay-defined seropositivity threshold for HPV-18 neutralizing antibodies and its exact two-sided 95% confidence interval are summarized separately for each prior-vaccination cohort.

  Months 84, 108, and 132 after the first dose in the base study

Secondary Outcomes (4)

• Geometric Mean Titer of HPV-16 Neutralizing Antibodies in Stored Serum Samples

  Before the first dose on Day 0 and at Months 7, 12, 24, and 36 after the first dose in the base study

• Geometric Mean Titer of HPV-18 Neutralizing Antibodies in Stored Serum Samples

  Before the first dose on Day 0 and at Months 7, 12, 24, and 36 after the first dose in the base study

• Seropositivity Rate for HPV-16 Neutralizing Antibodies in Stored Serum Samples

  Before the first dose on Day 0 and at Months 7, 12, 24, and 36 after the first dose in the base study

• Seropositivity Rate for HPV-18 Neutralizing Antibodies in Stored Serum Samples

  Before the first dose on Day 0 and at Months 7, 12, 24, and 36 after the first dose in the base study

Study Arms (3)

2-dose adolescent cohort

Participants who were aged 9 to 14 years at enrollment in the base study and received the bivalent HPV vaccine at Months 0 and 6. No vaccine is administered in the extension study.

Biological: Bivalent Human Papillomavirus Vaccine (Types 16 and 18, Pichia pastoris)

3-dose adolescent cohort

Participants who were aged 9 to 14 years at enrollment in the base study and received the bivalent HPV vaccine at Months 0, 2, and 6. No vaccine is administered in the extension study.

Biological: Bivalent Human Papillomavirus Vaccine (Types 16 and 18, Pichia pastoris)

3-dose adult cohort

Participants who were aged 18 to 26 years at enrollment in the base study and received the bivalent HPV vaccine at Months 0, 2, and 6. No vaccine is administered in the extension study.

Biological: Bivalent Human Papillomavirus Vaccine (Types 16 and 18, Pichia pastoris)

Interventions

Bivalent Human Papillomavirus Vaccine (Types 16 and 18, Pichia pastoris) BIOLOGICAL

Each 0.5 mL dose contained 40 micrograms of HPV-16 L1 virus-like particles and 20 micrograms of HPV-18 L1 virus-like particles adsorbed to aluminum phosphate. The vaccine was administered only in the base study 311-HPV-1004; no study vaccine is administered in 311-HPV-1004-EXTEND.

2-dose adolescent cohort; 3-dose adolescent cohort; 3-dose adult cohort

Eligibility Criteria

• Age: 16 Years - 34 Years
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

Females previously enrolled in study 311-HPV-1004 (NCT02740777) at the Hezhou and Zhongshan study sites in Guangxi, China, who completed the required blood-collection visits in the base study and met the eligibility criteria for the extension study.

You may qualify if:

• The participant, and the participant's legal guardian when applicable, is able to understand the study information and voluntarily sign the informed consent form for the extension study.
• In the investigator's judgment, the participant is able to comply with protocol requirements, including attending scheduled visits and responding to follow-up telephone contacts.
• The participant was enrolled in study 311-HPV-1004 and completed blood collection at Day 0 and Months 7, 12, 24, and 36.

You may not qualify if:

• Receipt of any HPV vaccine other than the study vaccine during study 311-HPV-1004 or between completion of that study and enrollment in this extension study.
• Use of an investigational or unregistered product, other than the study vaccine, during study 311-HPV-1004 or between completion of that study and enrollment in this extension study.
• Seropositivity for both HPV-16 and HPV-18 antibodies at baseline in study 311-HPV-1004.
• Long-term use of immunosuppressive agents or

Sponsors & Collaborators

• Shanghai Zerun Biotechnology Co.,Ltd: lead
• Yuxi Zerun Biotechnology Co., Ltd.: collaborator

Study Sites (2)

Hezhou Center for Disease Control and Prevention

Hezhou, Guangxi, China

Location

Zhongshan County Center for Disease Control and Prevention

Hezhou, Guangxi, China

Location

Related Publications (1)

• Li J, Shi LW, Li K, Huang LR, Li JB, Dong YL, Li W, Ji M, Yang Q, Zhou LY, Yuan L, Yan XM, Chen JJ, Jiang ZW, Qi YY, Li RC, Li YP, Xia JL, Yu BW, Mo ZJ, Li CG. Comparison of the safety and persistence of immunogenicity of bivalent HPV16/18 vaccine in healthy 9-14-year-old and 18-26-year-old Chinese females: A randomized, double-blind, non-inferiority clinical trial. Vaccine. 2023 Oct 26;41(48):7212-9. doi: 10.1016/j.vaccine.2023.10.041. Online ahead of print.

  PMID: 39492306 BACKGROUND

Related Links

• Related Info

Biospecimen

Retention: SAMPLES WITHOUT DNA

Serum collected at Months 84, 108, and 132 after the first dose in the base study for HPV-16 and HPV-18 neutralizing antibody testing. Stored serum from Day 0 and Months 7, 12, 24, and 36 is retested using the high-throughput pseudovirus-based neutralization assay.

MeSH Terms

Conditions

Papillomavirus Infections

Condition Hierarchy (Ancestors)

Sexually Transmitted Diseases, Viral; Sexually Transmitted Diseases; Communicable Diseases; Infections; DNA Virus Infections; Virus Diseases; Tumor Virus Infections; Genital Diseases; Urogenital Diseases; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 10, 2026
• First Posted: September 15, 2026
• Study Start: March 25, 2023
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): December 1, 2027
• Last Updated: September 17, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share

Locations

CN (2)