Merck & Co.’s Gardasil cervical cancer vaccine faces
serious doubts when it comes to its effectiveness in women over 18 if considering
its price, according to a study in the New England Journal of Medicine.
The study was conducted by two researchers at the Harvard School
of Public Health by analyzing the ratio between the cost of the vaccine,
screenings and treating cervical cancer and other illnesses targeted by the
vaccine.
Gardasil got its license in 2006 for use in girls and women
ages 9 to 26. Health officials recommend it for girls at age 11 or 12, before
beginning their sexual lives and some doctors offer it to women in their 20s in
“catch-up” vaccination campaigns. The vaccine is meant to prevent infection by
four strains of the human papillomavirus, transmitted through sexual activity. Two
of the targeted HPV strains are thought to cause about 70 percent of all
cervical-cancer cases. The other targeted strains cause most cases of genital
warts.
The vaccine offers increased protection to females that have
not been previously exposed to the four strains of HPV, which seems to fit
girls at age 11or 12. But when it comes to women who already started their
sexual lives, the vaccine might not be as effective because there is an increased
risk that they might have been exposed to the HPV strains and so the vaccine might
not justify its costs. However, the Centers for Disease Control and Prevention recommends
the vaccine to these women as well, because there is a chance that they might
not become exposed to all four HPV strains for many years.
The vaccine costs about $360 for a three-dose regimen. For the
study, researchers Jane Kim and Sue Goldie compared the price of the vaccine
and other expenses involved in getting the shot along with regular pap smears
(which detect abnormal cell change that could signify cervical cancer) to the
cost of pap smears. According to the National Institutes of Health, a pap smear
costs about $38.68 and is recommended at least once every three years for women
ages 21 though 64.
The researchers concluded that it would cost $43.600 to
extend life expectancy by one year when girls are vaccinated at 12. The study
found that when girls up to age 18 are included in the analysis, that ratio
rises to $97,300 and to $153,000 through age 26. A treatment is typically
considered cost effective if it is less than $50,000 or $100,000 for one
additional year of life, Kim said.
“We aren’t saying older women can’t benefit. We are just
saying that from a societal perspective there might be a better use of this
investment in money. You are getting diminishing returns,” Kim said.
Merck defended the vaccine saying, “there’s important value
in vaccinating all women who are in the indicated age groups,” Merck's head of
clinical research for Gardasil, Rick Haupt, said.
In an accompanying editorial in the New England Journal,
Charlotte Haung of the Journal of the Norwegian Medical Association says that
if the vaccine’ immunity fades over time, cervical cancer screening could prove
to be more cost-effective. Studies have shown that Gardasil’s immunity lasts at
least five years.
According to the American Cancer Society, about 11,000
Americans develop cervical cancer each year and nearly 4,000 die from it. Merck
is the only manufacturers of a cervical cancer vaccine. Rival GlaxoSmithKline
Plc’s Cervarix is sold in Europe and Australia and is now under the
FDA’s review.
The study was funded by the CDC, the American Cancer Society, the
National Cancer Institutes and the Bill and Melinda Gates Foundation.
