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An Extended Follow-Up Study of the HPV Vaccine Delayed Booster Trial

An Extended Follow-Up Study of the HPV Vaccine Delayed Booster Trial

Status
Active, not recruiting
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04688476
Enrollment
113
Registered
2020-12-30
Start date
2020-11-17
Completion date
2025-12-31
Last updated
2025-10-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

HPV-associated Cancer

Brief summary

This is an extended follow-up study to follow-up study participants who received 1 booster dose of Gardasil 9 in the HPV vaccine delayed booster trial. This was a prospective, single-arm, open-label, non-randomized, phase IIa trial among 9-11 year-old girls and boys to determine the immunogenicity after a single dose of the nonavalent HPV vaccine (Gardasil 9) over 24 months, with a delayed booster dose at 24 months and an optional booster at 30 months after the first dose. Participants provided blood specimens at 6, 12, 18, 24, and 30 months after the first dose. Serologic geometric mean titers (GMT) of the nine vaccine types (HPV 16/18/ 6/11/31/33/45/52/58) were measured at each time point. One hundred and thirty-three (133) participants received one booster dose at month 24 and elected not to receive the second booster at month 30. For this follow-up study, we anticipate that we will be able to accrue 120 participants from the original study who received just one booster dose. Participants who received one booster dose of Gardasil 9 will be contacted to return to the clinic to provide blood specimens at 48 (±3), 60 (±3), and 72 (±3) months after the priming dose. Serologic geometric mean titers (GMT) of the nine vaccine types (HPV 16/18/ 6/11/31/33/45/52/58) will be measured at each time point.

Interventions

None listed

Sponsors

National Cancer Institute (NCI)
CollaboratorNIH
University of California, Los Angeles
CollaboratorOTHER
University of Arizona
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Healthy volunteers
Yes

Inclusion criteria

* Study participants who received one booster dose of Gardasil 9 at month 24 and elected not to receive the second booster at month 30 in the original HPV vaccine delayed booster trial * Ability to understand and the willingness to sign a written informed consent document by the legal representative(s) of the participant. * Ability to understand and the willingness to sign a written assent document by the participant.

Exclusion criteria

\- Has received any HPV vaccine dose from an external source at any point during or after participation in the HPV vaccine delayed booster trial.

Design outcomes

Primary

MeasureTime frame
The differences in geometric mean titer (GMT) of HPV 16 and HPV18 between 30 vs. 48, 48 vs. 60, and 60 vs. 72 months after the priming dose of Gardasil72 months

Secondary

MeasureTime frame
The differences in geometric mean titer of other HPV types (HPV6/11/31/33/45/52/58) between 30 vs. 48, 48 vs. 60, and 60 vs. 72 months after the priming dose of Gardasil 972 months

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026