V503 in Chinese Girls 9-14 Years Old Versus Chinese Women 20-26 Years Old (V503-071)
About the study
This study aims to demonstrate that a 2-dose regimen of the 9-Valent Human Papillomavirus (9vHPV) vaccine (GARDASIL™9, V503) induces non-inferior competitive Luminex immunoassay (cLIA) geometric mean titers (GMTs) to each of the 9vHPV vaccine types in Chinese girls 9 through 14 years of age compared to a 3-dose regimen in Chinese women 20 through 26 years of age. The primary hypothesis is that a 2-dose regimen has a non-inferiority margin of 0.67 in the GMT ratio (girls vs. women) for each HPV type.
Who can take part
You may be eligible to participate in the study if you meet the following criteria:
INCLUSION CRITERIA
Inclusion Criteria:
- Is a healthy Chinese female.
- Is not a woman of childbearing potential (WOCBP); or is a WOCBP who has not had sex with males or has had sex with males and used effective contraception during Day 1 through 1 month post last dose.
EXCLUSION CRITERIA
The main inclusion and exclusion criteria include but are not limited to the following:
Exclusion Criteria:
- Has a history of known prior vaccination with an HPV vaccine.
- Has a history of severe allergic reaction that required medical intervention.
- Has a known thrombocytopenia or coagulation disorder that would contraindicate IM injections.
- Has a history of abnormal Pap test or external genital wart, vulvar intraepithelial neoplasia, vaginal intraepithelial neoplasia, anal intraepithelial neoplasia, vulvar cancer, vaginal cancer, or anal cancer.
- Has a history of a positive test for HPV.
- Has received immune globulin or blood-derived products in the past 6 months or plans to receive any before one month post last dose.
- Has a history of splenectomy, is currently immunocompromised, or has been diagnosed with immunodeficiency, human immunodeficiency virus, lymphoma, leukemia, systemic lupus erythematosus, rheumatoid arthritis, juvenile rheumatoid arthritis, inflammatory bowel disease, or other autoimmune condition.
- Has received immunosuppressive therapy in the past year, excluding inhaled, nasal, or topical corticosteroids and certain regimens of systemic corticosteroids.

Study Locations
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How to Apply
Contact the study center to learn if this study is a good match for you.
Study’s details
Contition
Papillomavirus Infections
Age (in years)
9 - 26
Phase
PHASE3
Participants needed
1500
Est. Completion Date
Aug 3, 2029
Treatment type
INTERVENTIONAL
Sponsor
Merck Sharp & Dohme LLC
ClinicalTrials.gov identifier
NCT05450705
Study number
V503-071
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