Editors’ note: Sexually active women risk contracting human papillomavirus (HPV), which causes genital warts and cervical cancer. Although a quadrivalent HPV (types 6,11, 16, and 18) vaccine has shown efficacy in young women (ages 16–23 years), the efficacy of the same vaccine in older women (age 24–45 years) is unknown. This phase III trial was done to test the vaccine efficacy in the older age range of women with no history of genital warts or cervical cancer. This prophylactic HPV vaccine seems to be efficacious in women aged 24-45 years.
Safety, immunogenicity, and efficacy of quadrivalent human papillomavirus (types 6, 11, 16, 18) recombinant vaccine in women aged 24—45 years: a randomised, double-blind trial