Could 2 HPV vaccine doses be enough? new study says maybe.
NCT ID NCT03943875
First seen Jun 24, 2026 · Last updated Jun 27, 2026 · Updated 1 time
Summary
This study looked at whether 2 doses of the HPV vaccine (Gardasil 9) protect as well as the standard 3 doses in people aged 15 to 26. Researchers measured antibody levels against nine HPV types. The goal is to see if a simpler schedule could work, making vaccination easier and cheaper.
What this could mean
Our plain-language read of the trial. This is informational only — not medical advice or a prediction.
- Active substance
- 9-valent HPV vaccine (Gardasil 9)
- What this could lead to
- If 2 doses work as well as 3, it could simplify HPV vaccination schedules, reduce costs, and make it easier for more people to get protected against HPV-related cancers.
- What could go wrong
- This is a completed Phase 4 study, but it only measured short-term antibody responses, not long-term cancer prevention. Two doses may not provide the same lasting protection as three doses.
This is an AI summary of the original study and may miss details. Read our disclaimer.
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Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
-
University of Texas Medical Branch
Galveston, Texas, 77555, United States
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