Source: www.medscape.org Author: Laurie Barclay, MD; Charles P. Vega, MD Quadrivalent human papillomavirus (HPV) vaccine may prevent infection with HPV types 6, 11, 16, and 18 and the development of related external genital lesions in young men 16 to 26 years old, according to the results of a randomized, placebo-controlled, double-blind trial reported in the February 3 issue of the New England Journal of Medicine. "Infection with ...HPV and diseases caused by HPV are common in boys and men," write Anna R. Giuliano, PhD, from the Risk Assessment, Detection, and Intervention Program, H. Lee Moffitt Cancer Center and Research Institute in Tampa, Florida, and colleagues. "We report on the safety of a quadrivalent vaccine (active against HPV types 6, 11, 16, and 18) and on its efficacy in preventing the development of external genital lesions and anogenital HPV infection in boys and men." The study sample consisted of 4065 healthy boys and men, aged 16 to 26 years, enrolled from 18 countries. The primary efficacy goal was to demonstrate that use of the quadrivalent HPV vaccine was associated with a lower incidence of external genital lesions related to HPV-6, 11, 16, or 18. The investigators used a per-protocol population, in which participants received all 3 vaccinations and had tested negative for relevant HPV types at enrollment, and an intent-to-treat population, in which participants received vaccine or placebo, regardless of baseline HPV status. In the intent-to-treat population, there were 36 external genital lesions in the vaccine group and 89 in the [...]