|By Alison Bryant|
From 2000 to 2009, rates of oral, vulva and anal cancers increased, according to a study by the National Cancer Institute. But if Merck and GSK both market HPV vaccines--Gardasil and Cervarix, respectively--then why the upward trend in cancer? "The investments we have made in HPV research to establish these relationships and to develop effective and safe vaccines against HPV will have the expected payoffs only if vaccination rates for girls and boys improve markedly," NCI Director Harold Varmus said, according to the report. To put it simply, a vaccine can't protect if people don't receive it.
Gardasil and Cervarix both still land in the top 20 selling vaccines for 2012, based on estimates made by EvaluatePharma. Gardasil takes the No. 2 spot on that list, raking in $1.78 billion, while Cervarix falls in at No. 11 with $581 million in sales. Gardasil has had a bit more time on the market, making its debut in 2006. Cervarix followed in 2009.
Though the companies' sales are nothing to scoff at, they can both do better; only a third of girls ages 13 to 17 have been fully vaccinated as of 2010, far below the 80% rate experts say is needed to significantly reduce the prevalence of infections. That leaves a full two-thirds of the available market untapped. The vaccine is a regimen of three shots; a mere 32% of U.S. females ages 13 to 17 received all shots.
Researchers can't pinpoint why the HPV vaccination rate is so low in the U.S. Neither Gardasil nor Cervarix makes it onto the list of vaccines required for school enrollment, which puts less pressure on parents to get their kids vaccinated, and the three-dose regimen means parents need to bring their kids to the doctor multiple times, which can be a hassle.
"Vaccination rates are still quite low in terms of where we need to be to really impact HPV infections," Edgar Simard, an author of the study and senior epidemiologist at the American Cancer Society, told Bloomberg. "If we don't address these disparities now they will continue to manifest."
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