(AP) -- A second kind of vaccine against cervical cancer may be added to the recommended list for girls and young women after a federal advisory panel voted Wednesday to support it.
The panel gave a limited endorsement to GlaxoSmithKline's vaccine, Cervarix, which the government licensed last week. Merck & Co. has had the vaccine Gardasil on the market since 2006.
The Advisory Committee on Immunization Practices did not state a preference for one vaccine over the other. But officials noted that while both protect against cervical cancer, the older Merck vaccine also protects against genital warts.
The committee advises a federal public health agency, the Centers for Disease Control and Prevention. The CDC still has to adopt the new recommendation for it to become official advice for U.S. physicians.
Both shots are a three-dose series that target two types of human papillomavirus, believed to be responsible for about 70 percent of cervical cancer cases. HPV is spread through sex.
The vaccine is considered most effective when given to girls at around age 11 or 12, before they become sexually active.
The Merck series costs about $390 and Glaxo's costs about $385.
Committee members discussed whether it was appropriate or not to give a subtle nod to one vaccine over the other. To some, the fact that Gardasil also targets two other types of HPV that cause genital warts was an important consideration. Genital warts are not a serious condition, but there are a half million such infections a year, many of them in teens and young adults.
"It has an enormous impact on relationships and self esteem," said Dr. James Turner, executive director of student health at the University of Virginia. Turner is not a voting member of the committee; he is a liaison to the committee on behalf of the American College Health Association.
Some cost-effectiveness studies have suggested the Glaxo vaccine series should be priced about $100 less than it is, since it doesn't protect against genital warts, said Harrell Chesson, a CDC economist.
But because it's slightly less expensive than the Merck vaccine, some patients and doctors may still choose it instead, some experts said.
More women getting the Glaxo vaccine reported pain, redness and swelling at the injection site. Committee members said that could be due to the fact that the vaccine uses a new kind of adjuvant - a chemical compound used to boost the immune system and stretch the vaccine's active ingredient, board members said.
CDC officials advised avoiding a statement on preference of one over the other. "We wanted to facilitate a market for both vaccines," said Dr. Lauri Markowitz, a CDC HPV expert.
No studies have addresses whether the vaccines are interchangeable - that is, if a girl can get, say, the Merck product for the first dose but the Glaxo product for one or both of the subsequent doses.
Neither vaccine is recommended for pregnant women - a precaution, because the effect of the vaccine on pregnant women and developing fetuses has not been thoroughly studied.
Last week, the Food and Drug Administration approved a new use for Gardasil, to prevent genital warts in boys.
The committee considered whether to recommend routine vaccination of boys against HPV, partly as a strategy to prevent the spread of HPV to girls. Fewer that 40 percent of the girls and young women recommended to get Gardasil have gotten a first shot, and fewer than 20 percent have had the whole three-dose series.
Some physicians who work with adolescents passionately endorsed such a step. But the committee decided not to do that, after hearing experts say such a strategy was not very cost effective, and female HPV vaccination rates are expected to rise without such a step.
But while doctors are not expected to prod families to get their boys vaccinated against HPV, the committee voted that for families who want it for their boys ages 9 to 18, it will be covered by a federal program that pays for vaccinations for children who are uninsured or on Medicaid or meet other criteria.
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