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GARDASIL 9: 3 Dose vs. 2 Dose With Delayed 3rd Dose

GARDASIL 9: 3 Dose vs. 2 Dose With Delayed 3rd Dose

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03943875
Enrollment
767
Registered
2019-05-09
Start date
2019-06-17
Completion date
2025-01-13
Last updated
2026-04-16

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

Conditions

Efficacy, Human Papilloma Virus, Immunization

Keywords

HPV vaccination, Gardasil 9, vaccine efficacy

Brief summary

The investigators are evaluating whether 15-26 year old males and females need a 3rd dose of the human papillomavirus (HPV) vaccine, or whether 2 doses provide similar protection as 3 doses from the 9 types of HPV that it protects against.

Detailed description

The investigators are studying an amended dosing regimen of an approved drug (Gardasil 9) in the population for which it is approved (vaccine is approved for ages 9-45 years and participants in this study will be 15-26 years of age.) The purpose of the study is to examine a delayed dosing schedule. The current recommendation is to administer the vaccine in 3 doses (administered at 0, 1-2 months and 6 months) to those 15-26 years of age but only 2 doses (0 and 6 months) if given at 9-14 years of age. The investigators will conduct a randomized study to determine if 2 doses will elicit an immune response similar to the standard 3 doses in those 15-26 years of age. Participants in the study group will receive 2 doses of Gardasil 9 at 0 and 6 months. Participants in the control group will receive 3 doses of Gardasil 9 at 0, 1-2 months and 6 months. All participants (Target Accrual n=512) will have 5 mLs of blood drawn at 0, 7, and 12 months. Following the 12 month blood draw, participants randomized to 2-doses will receive the 3rd dose. Potential participants will be recruited in the University of Texas Medical Branch (UTMB) clinics where providers have given the PI permission to directly contact patients. The investigators will also display signs and use email announcements at UTMB and other college campuses and will advertise the study online or by mail. The investigators will call UTMB patients if their provider gave permission to contact the patient, or if the patients gave prior consent to contact through the UTMB system. Potential participants (and their parents, if under 18 years of age) will be screened with inclusion/exclusion criteria. Eligible and interested parents and patients will sign informed written consent. Patients under 18 years of age will sign written assent. At the initial visit, eligible, consented participants will have their blood drawn, be randomized into either the study or control group, and receive a dose of the HPV vaccine. Participants will be re-screened against the inclusion/exclusion criteria at subsequent visits. All participants will receive compensation administered through a ClinCard following each of the 3 blood draws.

Interventions

BIOLOGICAL9-valent HPV vaccine, 2 dose efficacy

Evaluate the efficacy of 2 doses of the HPV vaccine across a 12 month period following the 1st dose among 15-26 year old males and females.

Will be comparison group for 2 dose efficacy group.

Sponsors

The University of Texas Medical Branch, Galveston
Lead SponsorOTHER
Cancer Prevention Research Institute of Texas
CollaboratorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
SINGLE (Outcomes Assessor)

Masking description

Vials submitted for assay will be de-identified and labeled only with the study ID number.

Eligibility

Sex/Gender
ALL
Age
15 Years to 26 Years
Healthy volunteers
Yes

Inclusion criteria

1. Males and females 15-26 years old. 2. Ability to give informed consent. All participants under 18 years of age must have the informed consent of a parent and must assent to participation. 3. Has not received any prior doses of the HPV vaccine. Investigators will ask the patient and his/her parent (if \<18) about prior vaccination and check the state registry (Immtrac), as well as the UTMB electronic medical record (if previously seen at UTMB), investigators will check with their primary care provider, if feasible, for patients who are not a previously established UTMB patient. 4. Identified source of funding for vaccine which may include Texas Vaccines for Children (VFC) program, Medicaid, the Children's Health Insurance Plan (CHIP), Texas Healthy Women program or other public or private health insurance. 5. Reliable telephone access. 6. Participant and parent/ guardian (if \<18) can read and speak either English or Spanish.

Exclusion criteria

1. For females, currently pregnant or plans to become pregnant or donate eggs in next 12 months. Sexually active females must report that they use regular birth control. All female subjects will be required to take a urine pregnancy test before each Gardasil 9 dose, unless it can be verified that she gave birth within the last week. Any subjects with positive tests at the initial visit will be disqualified from the study and advised to seek prenatal care. If a subject is pregnant when her follow-up visit window closes, she will be removed from the study. 2. History of 6 or more lifetime sexual partners. 3. History of any immunodeficiencies (HIV+, chemotherapy treatment, status splenectomy) or autoimmune disorders (lupus, thyroid disorder, psoriasis). 4. History of bleeding or platelet disorders such as hemophilia. 5. Currently taking medication which can suppress immune function including systemic corticosteroids, radiation therapy, cyclophosphamide, azathioprine, methotrexate, cyclosporine, leflunomide, TNF-alpha antagonists, monoclonal antibody therapies, or intravenous immunoglobulin treatment. 6. Known allergies to any components of the vaccine, including aluminum, yeast or Benzonase. 7. Febrile at ≥100°F in the 24 hours prior to vaccination. This will be reviewed before each Gardasil 9 dose. 8. Received any non-study inactive vaccines within the past 14 days or any live vaccines within the past 30 days. Those excluded for this reason will be re-screened under the same study number at a later date. 9. Plan to move out of the Galveston/Houston area in the 13 months following study entry.

Design outcomes

Primary

MeasureTime frameDescription
Short-term Human Papillomavirus (HPV) Type-specific Antibody Response for Type HPV-6Month 7Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 6, measured as % of participants who seroconvert
Short-term HPV Type-specific Antibody Response for Type HPV-11Month 7Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 11, measured as measured as % of participants who seroconvert.
Short-term HPV Type-specific Antibody Response for Type HPV-16Month 7Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 16, measured as % of participants who seroconvert
Short-term HPV Type-specific Antibody Response for Type HPV-18Month 7Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 18, measured as % of participants who seroconvert
Short-term HPV Type-specific Antibody Response for Type HPV-31Month 7Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 31, measured as % of participants who seroconvert
Short-term HPV Type-specific Antibody Response for Type HPV-33Month 7Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 33, measured as % of participants who seroconvert
Short-term HPV Type-specific Antibody Response for Type HPV-45Month 7Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 45, measured as % of participants who seroconvert
Short-term HPV Type-specific Antibody Response for Type HPV-52Month 7Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 52, measured as % of participants who seroconvert
Short-term HPV Type-specific Antibody Response for Type HPV-58Month 7Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 58, measured as % of participants who seroconvert
HPV Type-specific Antibody Response for Type HPV-6Month 12Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 6, measured as % of participants who seroconvert
HPV Type-specific Antibody Response for Type HPV-11Month 12Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 11, measured as % of participants who seroconvert
HPV Type-specific Antibody Response for Type HPV-16Month 12Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 16, measured as % of participants who seroconvert
HPV Type-specific Antibody Response for Type HPV-18Month 12Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 18, measured as % of participants who seroconvert
HPV Type-specific Antibody Response for Type HPV-31Month 12Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 31, measured as % of participants who seroconvert
HPV Type-specific Antibody Response for Type HPV-33Month 12Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 33, measured as % of participants who seroconvert
HPV Type-specific Antibody Response for Type HPV-45Month 12Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 45, measured as % of participants who seroconvert
HPV Type-specific Antibody Response for Type HPV-52Month 12Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 52, measured as % of participants who seroconvert
HPV Type-specific Antibody Response for Type HPV-58Month 12Yes/No for seroconversion, defined as changing from seronegative (no detectable antibodies) to seropositive (antibodies at or exceeding natural immunity levels) to HPV type 58, measured as % of participants who seroconvert

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORAbbey B Berenson, MD, PhD

University of Texas

Baseline characteristics

Characteristic
Age, Continuous20.63 Years
STANDARD_DEVIATION 3.85
Ethnicity (NIH/OMB)
Hispanic or Latino
66 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
148 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
28 Participants
Race (NIH/OMB)
Black or African American
118 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
1 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
572 Participants
Seropositivity at Baseline
HPV-11
138 Participants
Seropositivity at Baseline
HPV-16
34 Participants
Seropositivity at Baseline
HPV-18
50 Participants
Seropositivity at Baseline
HPV-31
120 Participants
Seropositivity at Baseline
HPV-33
82 Participants
Seropositivity at Baseline
HPV-45
82 Participants
Seropositivity at Baseline
HPV-52
33 Participants
Seropositivity at Baseline
HPV-58
43 Participants
Seropositivity at Baseline
HPV-6
45 Participants
Sex: Female, Male
Female
0 Participants
Sex: Female, Male
Male
164 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
deaths
Total, all-cause mortality
0 / 2210 / 2170 / 1650 / 164
other
Total, other adverse events
0 / 2210 / 2170 / 1650 / 164
serious
Total, serious adverse events
0 / 2210 / 2170 / 1650 / 164

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Apr 17, 2026