The purposes of this phase 3, double-blind, placebo-controlled clinical study are to evaluate the efficacy of V503 in preventing human papillomavirus (HPV)-related anogenital persistent infection, and to evaluate the safety/tolerability of V503, in Japanese males who are 16 to 26 years of age. It is hypothesized that administration of a 3-dose regimen of V503 reduces the combined incidence of HPV 6/11/16/18-related anogenital persistent infection, as well as the combined incidence of HPV 31/33/45/52/58-related anogenital persistent infection, compared with placebo. The study includes a Base Study to assess efficacy and safety of V503, and an Extension Study. Participants who received placebo in the Base Study will be eligible to receive V503 vaccine on Day 1, Month 2, and Month 6 of the Extension Study. Participants who received less than 3 doses of V503 in the Base Study will be offered the opportunity to complete the 3-dose regimen in the Extension Study.
Age range
16 Years – 26 Years
Sex
MALE
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AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
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Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
Base Study: Combined Incidence of Human Papillomavirus (HPV) 6/11/16/18-related Anogenital Persistent Infection
Timeframe: Up to approximately 36 Months
Base Study: Percentage of Participants With Solicited Injection-site Adverse Events (AEs)
Timeframe: Up to 5 days after any vaccination
Base Study: Percentage of Participants With ≥1 Systemic AE
Timeframe: Up to 15 days after any vaccination
Base Study: Percentage of Participants With ≥1 Serious Adverse Events (SAEs)
Timeframe: Up to approximately 37 months
Base Study: Number of Participants With Elevated Oral Body Temperature
Timeframe: Up to 5 days after any vaccination