The FDA announced today that it has approved the HPV vaccine for anal cancer and associated precancerous lesions related to human
papillomavirus types 6, 11, 16 and 18.
The new indication is for patients aged 9 through 26
years. Gardasil (Merck) is already approved for the same age population for the
prevention of cervical, vulvar and vaginal cancer and the associated
precancerous lesions caused by HPV types 6, 11, 16, and 18 in women and girls,
and for the prevention of genital warts caused by types 6 and 11 in both males
The FDA’s Vaccines and Related Biological Products
Advisory Committee recommended extending the indication for Gardasil earlier
Anal cancer is relatively rare, representing
approximately 4% of all lower gastrointestinal tract cancers diagnosed in the
US, but incidence is increasing and 90% of cases are related to HPV. The
American Cancer Society estimates that about 5,300 Americans are diagnosed with
anal cancer annually. Men who have sex with men (MSM) are at greatest risk, but
women make up 60% of diagnoses.
“Treatment for anal cancer is challenging,”
Karen Midthun, MD, director of the FDA’s Center for Biologics
Evaluation and Research, said in a press release. “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
Approval for the new indication is based on a single
randomized, controlled trial of 4,065 patients, including 602 men who have sex
with men. Among the MSM population, the point estimate of efficacy for Gardasil
was 78% (95% CI, 40-93) for the primary composite endpoint of prevention of any
grade anal intraepithelial neoplasia and anal cancer. Efficacy was 75% (95% CI,
9-93) for grade 2 or higher anal intraepithelial neoplasia.
There were no cases of invasive anal cancer in the
Overall efficacy was 50% (95% CI, 26-27) for any grade
anal intraepithelial neoplasia and anal cancer. For grade 2 or higher anal
intraepithelial neoplasia, efficacy was 54% (95% CI, 18-75).
Because anal cancer is the same disease in both males
and females, the effectiveness data was used to support the indication in
females as well.