The article describes the two prophylactic human papillomavirus (HPV) vaccines that are commercial available. These are the bivalent vaccine Cervarix from GlaxoSmithkline Biologicals and the quadrivalent vaccine Gardasil from Merck and Co. The article cites studies which show the efficacy of Cervarix and Gardasil for up to five years. It also explains that these vaccines may be co-administered with other non-live or live vaccines.