The Food and Drug Administration on Dec. 22 approved the Gardasil vaccine to prevent anal cancer and associated precancerous lesions due to human papillomavirus (HPV) types 6, 11, 16, and 18 in people aged 9-26 years.
The approval was expected, as in November, an FDA advisory committee agreed that the data submitted by Merck & Co. supported approval. Merck had filed for the additional approval in early 2010.
[FDA Committee Considers Gardasil for Anal Cancer Prevention]
"Treatment for anal cancer is challenging; the use of Gardasil as a method of prevention is important as it may result in fewer diagnoses and the subsequent surgery, radiation or chemotherapy that individuals need to endure," Dr. Karen Midthun, director of the FDA’s Center for Biologics Evaluation and Research, said in a statement.
Anal cancer is not common, affecting 5,300 people annually in the United States, according to estimates from the American Cancer Society. But HPV is associated with approximately 90% of anal cancer, according to the FDA.
The vaccine was approved based on data from a randomized, controlled trial of 602 men who have sex with men (MSM), a group known to be at the greatest risk for anal cancer. Those data were part of a larger study that led to Gardasil’s approval in 2009 for preventing genital warts in boys and men. The participants received three doses of vaccine or a placebo. Compared with placebo, the vaccine showed 78% effectiveness in preventing anal intraepithelial neoplasms – precursors to anal cancer – related to HPV types 6, 11, 16, and 18.
According to the FDA, because anal cancer is the same in both men and women, the effectiveness data could support approval in both sexes. The agency stressed that for all indications, the vaccine is most effective when given prior to infection.
The new approval could be cause for the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices to revisit a previous recommendation against routine HPV vaccination for boys and men for genital wart prevention. The ACIP meets in February.
Gardasil is approved in 121 countries and, according to Merck, since its first approval in 2006 through May 31, 2010, more than 65 million doses have been distributed worldwide. It is approved in the U.S. for use in girls and young women aged 9-26 years for the prevention of cervical, vulvar and vaginal cancers caused by HPV types 16 and 18; genital warts (condylomata acuminata) caused by HPV types 6 and 11; and precancerous or dysplastic lesions caused by HPV types 6, 11, 16 and 18.