This Phase 3 study was conducted to demonstrate that Gardasil™ (quadrivalent human papillomavirus [qHPV] vaccine) 1) is well tolerated in young men, 2) reduces the incidence of external genital lesions in young men, 3) reduces the incidence of anal intraepithelial neoplasia (AIN) or anal cancer in men having sex with men (MSM), and 4) reduces the incidence of Human Papillomavirus (HPV) infection in young men. In the 7-month Base Study participants received randomly assigned qHPV vaccine or placebo at Day 1, Month 2, and Month 6. Base Study follow-up continued through Month 36. In Extension 1 (EXT1), participants who received a placebo or an incomplete qHPV vaccine regimen in the Base Study were offered qHPV vaccine. Participants were followed in EXT1 for 7 months. In Extension 2 [LTFU (EXT2)], long-term effectiveness, immunogenicity, and safety of qHPV vaccine were followed up to 10 years following study enrollment. Participants who received ≥1 dose of qHPV vaccine in the Base Study or EXT1 were eligible to enroll in LTFU (EXT2).

Results

The Lancet published results on November 12, 2021

The quadrivalent HPV vaccine provides durable protection against anogenital disease related to HPV6, 11, 16, and 18. The results support quadrivalent HPV vaccination in men, including catch-up vaccination.