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GARDASIL 9: 3 Dose vs. 2 Dose With Delayed 3rd Dose
NCT03943875 · View on ClinicalTrials.gov ↗
Study 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.
Conditions Studied
Interventions
- BIOLOGICAL 9-valent HPV vaccine, 3 doses standard timing
- BIOLOGICAL 9-valent HPV vaccine, 2 dose efficacy
Study Locations (1)
Texas
- University of Texas Medical Branch — Galveston
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 767 participants |
| Start Date | 2019-06-17 |
| Est. Completion | 2026-03-01 |
| Phase | Phase 4 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT03943875
The ClinicalTrials.gov registry entry for NCT03943875 describes a study currently listed as active not recruiting. It is categorized as Phase 4, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 767 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is The University of Texas Medical Branch, Galveston, which has 132 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 3 conditions, with Human Papilloma Virus appearing as the primary indexed condition, and to 2 interventions — of which 9-valent HPV vaccine, 3 doses standard timing is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT03943875 reports 1 study location spanning 1 distinct geographic area — top geographies include Texas. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT03943875 about?
NCT03943875 is a clinical study titled "GARDASIL 9: 3 Dose vs. 2 Dose With Delayed 3rd Dose". 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.
What is the current status of trial NCT03943875?
This trial is currently active not recruiting. It is a Phase 4 study. The enrollment target is 767 participants. The study started on 2019-06-17. Estimated completion is 2026-03-01.
What conditions does trial NCT03943875 study?
This clinical trial studies the following conditions: Human Papilloma Virus, Immunization, Efficacy. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT03943875?
The interventions under investigation include: 9-valent HPV vaccine, 3 doses standard timing (BIOLOGICAL), 9-valent HPV vaccine, 2 dose efficacy (BIOLOGICAL). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT03943875?
This trial is sponsored by The University of Texas Medical Branch, Galveston, which has 132 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT03943875 being conducted?
This trial has 1 study location across Texas. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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