The vaccine, which works by building immunity against the sexually
transmitted human papillomavirus, was found to be effective in preventing almost
three-quarters of all cervical cancers.
"This vaccine is a significant advance in the protection of women's
health in that it strikes at the infections that are the root cause of many
cervical cancers," said FDA Acting Commissioner Andrew von Eschenbach.
He predicted that the vaccine -- the first ever designed specifically to
prevent a cancer -- will have a "dramatic effect" on the health of
women worldwide.
The vaccine, called Gardisil and developed by Merck & Co., was approved
for girls and women ages 9 and 26. It is most useful if given to younger girls,
because the vaccine is ineffective once the virus -- which is very common among
sexually active people -- is already present.
The prospect of young girls receiving the vaccine has disturbed some social
conservatives, who adamantly oppose efforts to make the vaccination mandatory.
They say that sexual abstinence is the best way to avoid getting the virus.
But women's and public health groups are pressing hard for early and
mandatory vaccinations, saying they will potentially save thousands of lives.
"The most effective vaccination programs are either given to young
children or are mandated for attending school," said Jeffrey Waldman,
senior director for clinical affairs for Planned Parenthood Federation of
America. "Clearly, to have the greatest benefit, this vaccine would be
given to all girls -- and in the future, maybe boys -- before they become
sexually active."
Merck said in a statement yesterday that the vaccine can be ordered
immediately, but the company was not specific on when the drug might be
available for use. Doctors will be free to administer the vaccine as soon as it
is distributed.
A Centers for Disease Control and Prevention advisory committee will decide
June 29 whether the vaccine should be incorporated into routine vaccination
schedules, in effect determining whether it will become the standard of care. If
the CDC does, as expected, give the vaccine strong support, each state would
have to determine whether the vaccine will be mandatory for school attendance.
The federal government and states will also have to decide whether to subsidize
its price.
On its Web site, the company said the catalogue price for Gardisil will be
120 per dose, and protection will require three doses over six months. That
price has raised concerns that the vaccine will not be widely available to poor
women or in less developed nations, where incidence of cervical cancer is
considerably higher than in the
United States
.
The CDC estimates that about 6.2 million Americans become infected with
genital HPV each year and that more than half of all sexually active men and
women become infected in their lives. More than 9,700 new cases of cervical
cancer and 3,700 deaths are attributed to the virus yearly in the
United States
. Worldwide, cervical cancer is the second most common cancer in women, with
470,000 new cases annually and 233,000 deaths.
The disease used to be far more common in the
United States
, but the widespread use of pap smears -- which detect precancerous lesions and
early cancer -- has dramatically reduced the number of cases. Officials said
despite the effectiveness of the new vaccine, women should continue to get pap
smears because about a quarter of cervical cancer cases are caused by viruses
that are not blocked by the vaccine.
The research that discovered the link between HPV and cervical cancer was
largely done at the National Cancer Institute, which also developed much of the
technology for making the vaccine. Both Merck and GlaxoSmithKline, which also
has an HPV vaccine near completion, developed their products based in part on
the NCI work.
The vaccine was reviewed and approved within six months by the FDA after the
agency deemed it a priority product. It is genetically engineered and does not
contain live viruses that could theoretically cause disease.
Jesse Goodman, director of FDA's Center for Biologics Evaluation and
Research, said the vaccine is known to be effective for at least 3 1/2 years and
may need a booster after that. He said Merck and the FDA will be monitoring its
continued effectiveness as well as possible side effects that might not have
been detected during clinical testing. Studies to date have shown the vaccine to
be largely without side effects, he said.
While the vaccine is almost 100 percent effective in protecting against four
variants of HPV, the FDA said it may not protect people already infected and
might increase their risk of developing the kind of lesions that can lead to
cervical cancer.
Gardisil was approved earlier this month in
Mexico
, and applications are pending in more than 50 nations. Merck is also working
with
India
's Council of Medical Research to study the vaccine in a developing area, and
with the Gates Foundation and others to develop HPV vaccination programs in the
poorest nations.
FDA's approval was almost universally hailed, but the vaccine could yet
become controversial. Vaccines are always most effective when there is a
"herd immunity," when enough people are immunized that the pathogen
gradually disappears.
With that dynamic in mind, public health advocates will be pushing for the
broadest use possible. Amy Allina, program director of the National Women's
Health Network, said "the potential of this technology will only be
realized if it is made accessible to the women who are at greatest risk for
cervical cancer."
But on its Web site, the group Focus on the Family said it "supports
widespread (universal) availability of the HPV vaccines but opposes mandatory
HPV vaccination for entry to public school. As in all areas of sexual health and
education, Focus on the Family upholds parents' right to be the primary decision
maker and educator for their children."