WEDNESDAY, Oct. 21 (HealthDay News) -- A U.S. advisory panel on Wednesday voted against the routine use of the vaccine Gardasil in boys and men, but did leave individual doctors free to recommend the vaccine for males as an option.
Gardasil protects against four strains of the human papilloma virus (HPV), a sexually transmitted pathogen that is thought to cause 70 percent of cervical cancers. HPV has also been linked to rarer cancers of the throat, genitals and anus, as well as genital warts, and its use among males has been the subject of much debate since Gardasil first received FDA approval for use in females in 2006.
However, the Advisory Committee on Immunization Practices, which reports its findings to the U.S. Centers for Disease Control and Prevention, stopped short of recommending the vaccine for boys as part of the approved childhood immunization schedule, Bloomberg News reported.
Earlier this month, the U.S. Food and Drug Administration approved Gardasil for the prevention genital warts in males aged 9 through 26.
Advocates for widening routine HPV immunization to males reason that since males transmit the virus to females, immunizing boys and young men might reduce cervical cancer rates.
But that argument sustained a serious blow earlier this month after a study found that the cost of giving boys the vaccine would outweigh any health benefit.
Researchers from the Harvard School of Public Health conducted an analysis comparing a girls-only vaccination program with a co-ed vaccination program.
"This study found that while vaccine coverage and efficacy are high in girls, including boys in an HPV vaccination program generally exceeds what the U.S. typically considers good value for money," lead researcher Jane Kim, an assistant professor of health decision science, said at the time of the study's release in the British Medical Journal.
Vaccination was considered a good value if cost-effectiveness ratios ranged from $50,000 to $100,000 per quality-adjusted life year, meaning the cost of the vaccine vs. the number of added years someone would gain by getting the vaccine.
Assuming 75 percent coverage and lifelong protection, the researchers found routine vaccination of 12-year-old girls was a good value at less than $50,000 per quality-adjusted life year. However, adding preadolescent boys increased the cost-effectiveness ratio to more than $100,000 per quality-adjusted life year. The researchers considered treatment for conditions caused by HPV, including anogenital and oral cancers, genital warts, and juvenile-onset recurrent respiratory papillomatosis.
"Only under optimistic assumptions of high, lifelong vaccine efficacy against all HPV-related health conditions, or lower vaccine efficacy accompanied by lower coverage or vaccine costs, did vaccinating both girls and boys fall below $100,000 per quality-adjusted life year," Kim said.
Debbie Saslow, director of breast and gynecologic cancer at the American Cancer Society, agreed with the findings.
"If we can vaccinate a high enough proportion of young girls, then vaccinating boys is not cost-effective," she said.
Reacting to the panel's vote on Wednesday, Gardasil's maker, Merck & Co, took issue with the ruling.
"Approximately 75 to 80 percent of males and females will acquire one or more types of HPV in their lives and HPV-related diseases cause significant personal and public health burden for both men and women," Merck spokeswoman Pam Eisele told Bloomberg. "As such, we believe there is value in vaccinating both young men and women with Gardasil to help protect them from certain diseases caused by HPV."
Since Gardasil's approval, studies have found it safe and nearly 100 percent effective in preventing precancerous cervical lesions from the four HPV strains targeted by the vaccine.
Studies have also found that Gardasil far more effective when given to girls or young women before they become sexually active.
In another vote on Wednesday, the ACIP panel approved the use of a second HPV vaccine, GlaxoSmithKline's Cervarix, for use in females to prevent cervical cancer. Last week, the FDA approved Cervarix for use in girls and women ages 10 to 26.
For more on HPV vaccine, visit the U.S. Centers for Disease Control and Prevention.
SOURCES: Jane Kim, Ph.D., assistant professor, health decision science, Harvard School of Public Health, Boston; Philip E. Castle, Ph.D., M.P.H., investigator, division of cancer epidemiology and genetics, U.S. National Cancer Institute, Bethesda, Md. ; Debbie Saslow, Ph.D., director, breast and gynecologic cancer, American Cancer Society; Oct. 9, 2009, British Medical Journal online; Oct. 21, 2009, Bloomberg News