Cervical cancer is the second most common cancer in women worldwide. Persistent infection with the human papillomavirus (HPV) is the main cause of the disease. The most common HPV types associated with the disease are HPV-16 and HPV-18. In a trial in 2004, Diane Harper (Dartmouth Medical School, Hanover, NH, USA) and colleagues found that a vaccine against these viruses could prevent cervical cancer, but its long-term effectiveness and safety was unclear.
To investigate, Dr Harper's team followed-up 800 women from the original trial who had received three doses of the HPV-16/HPV-18 vaccine or placebo. The researchers found that women given the vaccine had sustained high levels of antibodies against HPV-16 and HPV-18 for up to 4.5 years after receiving the last dose of the vaccine. The antibody levels did not decrease as is commonly seen at 4 years in other vaccines, state the authors. The team found that the vaccine was effective against persistent and new infections and protected against infection with HPV-45 and 31--the third and fourth most prevalent oncogenic types of HPV. The vaccine also had a good long-term safety profile and provided substantial long-term protection against cancerous cell changes associated with high-risk HPV types.
Dr Harper states: "These findings set the stage for the widescale adoption of HPV vaccination for prevention of cervical cancer."
Contact: Deborah Kimbell, Public Relations, Dartmouth Medical School. T) 603-653-1913 / 603-615-4628 (pager)
Dr Diane M Harper, Dartmouth Medical School, Gynaecologic Cancer Prevention Research Group, Rubin 880, One Medical Center Drive, Lebanon, NH 03756, USA. T) 603-236-6767 diane.m.harper@dartmouth.edu
Journal
The Lancet