BOSTON – A study published Thursday in the New England Journal of Medicine shows it is very cost-effective to administer human papillomavirus (HPV) vaccines to all preadolescent girls in the United States, but it becomes less cost-effective at later ages, especially after 21.
Infection with high-risk types of HPV is the cause of 100 percent of cervical cancers, 90 percent of anal cancers and 40 percent of vulvar and vaginal cancers, and is associated with a share of several other cancers as well, the study notes. Two types of HPV account for about 70 percent of cervical cancers worldwide, and vaccines against them appear to be highly effective.
In July 2006, the U.S. Food and Drug Administration approved Merck’s HPV vaccine Gardasil for sale to girls and women ages 9 to 26, and the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices voted unanimously soon after to recommend that girls ages 11 and 12 be vaccinated.
The CDC has also advised that a temporary “catch-up” vaccination be given to women between 13 and 26 who were not immunized.
The new study, conducted at the Harvard School of Public Health using computer models – since the lifetime impact of the vaccines won’t be seen for decades – estimated the cost per “quality-adjusted life year” (QALY) gained to be $43,600 when vaccinating 12-year-olds, but more than double that, $97,300 per QALY, if the program is extended to 18-year-olds. If extended to age 21, the cost rises to $120,400 per QALY, up to age 26, to $152,700.
The study noted that some analysts consider a cost of $50,000 to be worthwhile, but others set the cost-effectiveness line at $100,000. There are other variables as well, the researchers noted, such as how well all women are screened for HPV over the course of their adult lives.
The study is available at content.nejm.org.
