Immunologic responses following administration of a vaccine targeting human papillomavirus Types 6, 11, 16, and 18

Human papillomavirus (HPV) infection causes cervical cancer and genital warts. Young women (1106) were randomized to receive one of three formulations of a quadrivalent HPV (Types 6/11/16/18) L1 virus-like particle (VLP) vaccine or one of two placebo formulations. The goal was to assess vaccine safety and immunogenicity in baseline HPV 6/11/16 or 18-naive and previously infected subjects. All three formulations were highly immunogenic. At Month 2 (postdose 1), among women with vaccine-type antibodies at baseline, vaccine-induced anti-HPV responses were similar to 12- to 26-fold higher than those observed in baseline-naive women, suggesting an anamnestic response. Following an initial, similar sized decline, anti-HPV responses plateaued and remained stable through end-of-study (3.0 years). No vaccine-related serious adverse experiences were reported. (c) 2006 Elsevier Ltd. All rights reserved.2427-285571558