The Lancet
Jun 06, 2009   Volume 373  Number 9679  Pages 1919 – 1996
http://www.thelancet.com/journals/lancet/issue/current

Article
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
Nubia Muñoz, Ricardo Manalastas, Punee Pitisuttithum, Damrong Tresukosol, Joseph Monsonego, Kevin Ault, Christine Clavel, Joaquin Luna, Evan Myers, Sara Hood, Oliver Bautista, Janine Bryan, Frank J Taddeo, Mark T Esser, Scott Vuocolo, Richard M Haupt, Eliav Barr, Alfred Saah
Preview
The quadrivalent HPV vaccine is efficacious in women aged 24–45 years not infected with the relevant HPV types at enrolment.