The Food and Drug Administration (FDA) recently green-lighted Cervarix, the second vaccine designed to prevent infections caused by the human papilloma virus (HPV), a serious risk factor for cervical cancer. Cervarix, manufactured by GlaxoSmithKline, targets "high risk" HPV types 16 and 18, the 2 strains responsible for about 70% of all cervical cancers, and is approved for use in girls and women aged 10 through 25.

HPV is a group of more than 100 related viruses that can spread during skin-to-skin contact – including vaginal intercourse, anal intercourse, and even during oral sex. HPV causes genital warts, though many people can be infected and not show any symptoms. Many women get HPV; in most cases, it goes away without treatment, but in some women, HPV lingers, potentially leading to cervical cancer.

In 2009, more than 11,000 women in the US will be diagnosed with cervical cancer and about 4,000 women will die from the disease. Almost all (more than 99%) cervical cancers are related to HPV. To reduce the risk of HPV infection, doctors encourage young women to postpone sex, practice safer sex (condoms afford some – but not total – protection against infection), and depending on their age group, to get vaccinated.

Cervarix joins Gardasil (made by Merck) as the newest HPV vaccine with FDA approval.

In a study of more than 18,000 girls and women aged 15 to 25, Cervarix was about 93% effective in preventing precancerous lesions caused by HPV 16 and 18 among those who received all 3 doses of the vaccine were not infected with HPV 16 or 18 at the start of the study. Cervarix was not effective in those who had already been infected with HPV. The most common side effects included pain, redness, and swelling at the injection site; fatigue; headache; muscle and joint aches; and gastrointestinal distress. The vaccine is given in a series of 3 injections over a 6-month period.

"The licensure of Cervarix adds another option in the prevention of cervical cancer,” said Karen Midthun, MD, acting director of the FDA’s Center for Biologics Evaluation and Research. “It has the potential to save lives from cervical cancer as well as reduce the need for biopsies and invasive procedures associated with the necessary follow-up from abnormal Pap tests."

Gardasil, the other FDA-approved vaccine, protects against HPV types 16 and 18, as well as types 6 and 11, strains that cause genital warts. Like Cervarix, it's given 3 times over the course of 6 months. Its approval was recently extended for use in boys and men ages 9-26 to help prevent genital warts.

To date, there haven't been any head-to-head comparisons of the 2 vaccines. The Gardasil vaccine series costs around $360 (not including any doctor’s fee or the cost of giving the injections). GlaxoSmithKline has not yet disclosed a price for Cervarix.

The American Cancer Society is reviewing the data on Cervarix. ACS currently recommends that Gardasil be routinely given to females aged 11 to 12 and as early as age 9 years at the discretion of doctors, and agrees that “catch-up” vaccinations should be given to females aged 13 to 18. Women aged 19 to 26 years should talk with their health care provider about the risk of previous HPV exposure and potential benefit from vaccination before deciding to get vaccinated.

Vaccines don't protect against all cancer-causing types of HPV, so routine Pap tests are still necessary. To learn more about reducing cervical cancer risk, see our document Cervical Cancer. To learn more about HPV, see Human Papilloma Virus (HPV), Cancer, and HPV Vaccines – Frequently Asked Questions.

Reviewed by: Members of the ACS Medical Content Staff