September 12, 2008
The FDA today announced that the vaccine Gardasil may be used to prevent some cancers of the vulva and vagina in girls and women ages 9-26.
Gardasil is already approved to help prevent a leading cause of cervical cancer in women of that same age range.
Gardasil targets four strains of the human papillomavirus (HPV) that cause most cases of cervical cancer. Two of those HPV strains can also cause some vulvar and vaginal cancers.
“There is now strong evidence showing that this vaccine can help prevent vulvar and vaginal cancers due to the same viruses for which it also helps protect against cervical cancer,” Jesse L. Goodman, MD, MPH, director of the FDA’s Center for Biologics Evaluation and Research, says in a news release.
“While vulvar and vaginal cancers are rare, the opportunity to help prevent them is potentially an important additional benefit from immunization against HPV,” Goodman says.
Gardasil and HPV
Gardasil first gained FDA approval in 2006 for use in girls and women aged 9-26 to help prevent cervical cancer, precancerous genital lesions, and genital warts.
The CDC recommends Gardasil for all girls aged 11-12. Girls can get Gardasil when they’re as young as 9. If they miss vaccination at ages 11-12, they can get vaccinated by age 26.
To be most effective, Gardasil should be given before a girl becomes sexually active. There are more than 100 strains of the HPV virus, and more than 30 of those strains can be spread through sex. According to the CDC, HPV is the most common sexually transmitted infection in the U.S, with some 6 million Americans becoming infected with genital HPV each year.
HPV doesn’t always cause cervical cancer. For most women, the body’s own defense system will clear HPV, preventing serious health problems. But some HPV types can cause abnormal cell growth in areas of the cervix, vagina, vulva, and other areas that years later may turn into cancer.
Men can also carry HPV. But Gardasil isn’t approved for use in men.
Gardasil vs. Vulvar, Vaginal Cancers
The FDA approved Gardasil to help prevent vulvar and vaginal cancers based on a follow-up report from Merck, the drug company that makes Gardasil, on more than 15,000 participants from Gardasil’s original studies.
Merck followed those participants for two extra years and found that Gardasil was highly effective at preventing precancerous vulvar and vaginal growths related to HPV types 16 and 18, which the vaccine targets.
But Gardasil only showed that benefit in women who hadn’t been infected with HPV before getting Gardasil.