Vaccine for cervical cancer shows promise

A vaccine against a cervical cancer causing virus can protect young women from infection, a success researchers hope will eventually allow them to prevent many cases of cervical cancer. Cervical cancer is the second most common cancer in women after breast cancer. It is most common between the ages of 45-50 years, and the risk increases with age. Low socio-economic group, poor dental hygiene, active sexual life at an early age, multiple sexual partners, male sexual partner with multiple partners and smoking are the risk factors. Immunization with an experimental vaccine against human papillomavirus (HPV) type 16 prevents infection with the virus. Persistent infection with HPV 16 or with one of several other high-risk HPVs raises a woman's risk of cervical cancer. Researchers hope that vaccinating against the culprit HPV strains will one day slash rates of the cancer worldwide. The researchers from the University of Washington at Seattle, USA assessed HPV infection rates in 2392 women, 16 to 23 years of age, who were randomised to receive three doses of HPV-16 virus-like-particle vaccine or placebo. The doses were given at day 0, month 2, and month 6. The primary efficacy analysis was limited to 1533 women who did not test positive for HPV-16 infection either at enrolment or at month 7. The follow-up period after completing the vaccination regimen was 17.4 months. The incidence of persistent HPV-16 infection was 3.8 per 100 woman-years at risk in the placebo group and 0 per 100 woman-years at risk in the vaccine group (100 percent efficacy). Administration of this HPV-16 vaccine reduced the incidence of HPV-16 infection. Immunizing HPV-16-negative women may eventually reduce the incidence of cervical cancer. If HPV vaccination becomes a reality, it could drastically change the face of cervical cancer care, which is currently best managed by early detection through regular Pap tests. Several HPVs are implicated in cervical cancer, and vaccinating against only one type will not ward off the others. A vaccine that would protect against a broad spectrum of HPV types is currently under study and this would be more advantageous.