The Food and Drug Administration approved Friday Merck & Co.'s cervical cancer vaccine, Gardasil, for the prevention of vulvar and vaginal cancer.

Gardasil, which was FDA-approved in 2006 as vaccine against the human papillomavirus or HPV, also protects against cancers of the vagina and vulva, which inflicts over 5,000 women in the U.S. annually, according to Merck.

Gardasil protects women against four strains of HPV, which are among the causes of cervical cancers.

Merck is also looking at the effectiveness of Gardasil in men, and plans to submit a study on this to the FDA before the yearend.