Prophylactic human papillomavirus vaccines to prevent cervical cancer: review of the Phase II and III trials

Abstract

Cervical cancer may be substantially prevented by human papillomavirus (HPV) vaccination. The two most common oncogenic HPV types causing 70% of all cervical cancers are represented in the vaccines by synthetic virus-like particles to the L1 protein of HPV 16 and 18. The virus-like particles and adjuvant systems promote long-term antibody response. Phase II trials indicated vaccine efficacy against type-specific infection, initial vaccine immunogenicity and the tolerability of initial vaccination. Although designed to be preliminary evidence of disease prevention, the Phase II trials have become the sentinel beacon of longer-term efficacy for infection and disease outcomes, immunogenicity and safety after at least 5 years of follow-up. Both vaccines were approved for licensure after corroborative favorable Phase III trial data on efficacy, immunogenicity and safety. Vaccination programs targeted to a large age range of women will achieve cervical cancer reductions several decades from now.