Science Feature - July 2010
Tex Med. 2010;106(7):39-41.
By Ken Ortolon
Just about everyone agrees that reducing the rate of human papillomavirus (HPV) infections is a laudable goal. After all, HPV is the leading cause of cervical cancer and can cause genital warts and several other extremely rare types of cancer.
But experts can't seem to agree on the best way to prevent the spread of HPV. Even two Texas Medical Association committees can't agree.
The controversy centers on the recent approval of Gardasil - one of two available vaccines for preventing HPV infections - for use in boys and young men. While some experts believe the vaccine should be recommended for all boys, others question the cost effectiveness of giving it to boys since they do not get cervical cancer.
"Really, this is a question of cancer prevention policy," said Austin oncologist Debra Ann Patt, MD, MPH, a member of TMA's Committee on Cancer. "If you look at the indication for women, we know that it decreases their incidence of human papillomavirus lesions and of cervical cancer. But in men, policymakers and health care professionals find it hard to convey the need for vaccination, as men are not affected directly by cervical cancer, though they are a vector that spreads the causative virus."
Still, Dr. Patt and others say vaccinating boys and young men against HPV protects them from genital warts and some cancers and helps decrease HPV infections and their related cancers in women.
Stirring Up Controversy
HPV causes genital warts and various cancers in men and women and accounts for more than 90 percent of all cervical cancers. In addition, HPV causes many less common cancers, including penile and anal cancers, and some cancers of the head and neck.
Cervical cancer historically has been a major cause of cancer-related mortality for women in the United States; however, the incidence declined by more than 75 percent from the 1950s to the 1990s, largely due to Pap smear tests. Despite this, there are more than 11,000 cases of cervical cancer diagnosed annually and more than 4,000 deaths. Experts say the vaccines against the HPV virus, if used appropriately, can decrease that incidence significantly.
Gardasil, manufactured by Merck & Co. Inc., is a quadrivalent HPV vaccine because it protects against four different strains of HPV that can cause cervical cancer. A bivalent vaccine, Cervarix, made by GlaxoSmithKline, also is approved for use in girls and young women, but it protects against only two forms of HPV.
Controversy has surrounded Gardasil since 2006, when the U.S. Centers for Disease Control and Prevention's (CDC's) Advisory Committee on Immunization Practices (ACIP) recommended the routine vaccination of girls aged 11 to 12 with three doses of the vaccine and the vaccination of young women aged 13 to 26 who have not completed the full series and who are not sexually active.
While the vaccine is recommended for 11- and 12-year-olds, girls as young as 9 may get the vaccine.
Dr. Patt says many parents were concerned that vaccinating their daughters against a sexually transmitted disease might be tantamount to giving them approval to become sexually active. But, she says, the importance of vaccination before HPV exposure is not well understood.
"Another concern that has been raised is that parents feel they should not pay the high cost of the vaccine, nor expose their children to the risk, albeit low, of side effects if they perceive their children to be at low risk," Dr. Patt said. "Parents may often perceive their children to be at low risk if they do not believe they will be sexually active until marriage or will have few partners. Unfortunately, there is a stigma associated with the belief that someone may be exposed to HPV as it is a sexually transmitted disease."
Controversy - primarily over cost and how well it protects men - flared again in 2009 when the U.S. Food and Drug Administration approved Gardasil for males aged 9 to 26 .
Vincent Fonseca, MD, MPH, former state epidemiologist and a member of TMA's Physician Oncology Education Program, says Gardasil is expensive, costing about $120 per dose wholesale, or $360 per person for a full three-dose course.
Dr. Fonseca says the cost likely is one reason the ACIP decided not to recommend adding Gardasil to the CDC's recommended immunization schedule for boys. The vaccine is on the immunization schedule for girls.
"CDC did not add this vaccine to the recommended immunization schedules for males in these age groups because studies suggest that the best way to prevent the most disease due to HPV is to vaccinate as many girls and women as possible," the agency said in a statement on its website. "Parents of boys can decide if Gardasil is right for their sons by talking with their sons' health care providers. Young men can also discuss this vaccine with their doctors."
Dr. Fonseca supports the permissive recommendation for use of Gardasil in boys. TMA's Committee on Child and Adolescent Health agrees. In a recommendation presented to the TMA House of Delegates in late April, the committee chose not to support vaccination of all boys because of doubts about its cost effectiveness.
"While there is limited data on long-term HPV vaccine efficacy for males and females, various analyses generally concur that vaccinating females before they are exposed to HPV is cost effective," the committee concluded. "However, one study suggests a vaccination program including boys is likely to exceed generally accepted guidelines for good value for money."
The Committee on Cancer, however, took the opposite position. The policy that committee presented to the House of Delegates in late April urged support for vaccinating all individuals between ages 9 and 26.
The House of Delegates took the middle ground, adopting a recommendation that encourages females and males between ages 9 and 26 to receive the three-dose HPV vaccine series, but also supporting the current ACIP recommendation that includes the vaccine only on the immunization schedule for girls.
Attacking the Vector
Dr. Patt says that even though boys don't get cervical cancer, vaccinating them actually provides a double benefit because it protects them from genital warts, as well as penile cancer, anal cancer, and head and neck cancer. Plus, it increases protection for females.
"What's important from a public health policy standpoint is that men are often the vector for transmission [of HPV]," she said. "If you decrease the incidence of human papillomavirus - or at least the human papillomavirus that induces cervical cancer - among men, it's like creating herd immunity against the human papillomavirus that has carcinogenic potential. That would further decrease the cervical cancer rate among women, even if women weren't immunized."
Experts say there is little data yet on how widely Gardasil has been used in boys in the eight months since the ACIP made its recommendation. A spokesperson for the Texas Pediatric Society says pediatricians seem to be split on whether to recommend the vaccine for all boys. Some recommend it only for boys they believe may be predisposed to behaviors that put them at risk for HPV infection, she says.
A spokesperson for the Texas Department of State Health Services (DSHS) says the state's Vaccines for Children Program (VFC) has distributed 792,042 doses of Gardasil since it was added to the VFC vaccine list in February 2007. DSHS, however, does not maintain data on how many of those doses were given to girls and how many were given to boys.
Whether they support the current ACIP recommendation or believe all boys should get the vaccine, all experts seem to agree that the biggest barrier to vaccination against HPV is cost. While TMA officials say most health plans cover the vaccine for both boys and girls unless an employer specifically excludes it from their benefits, the high cost is a barrier for the uninsured and low-income families.
Dr. Fonseca says the ACIP recommendation cleared the way for the VFC to add the vaccine to the list of approved vaccines for uninsured and underinsured boys.
"Just like with other vaccines, there's the clinical recommendation, but we know what can make a big difference is the coverage recommendation," he said. "ACIP recommended that the vaccine may be used, and then VFC made the administrative coverage decision to include that as one of the covered products."
While the controversy is likely to continue, Dr. Fonseca says the current policy is "good enough for now. It will get boys what they need to get, which is access to an effective, safe vaccine."
Ken Ortolon can be reached by telephone at (800) 880-1300, ext. 1392, or (512) 370-1392; by fax at (512) 370-1629; or by e-mail at Ken Ortolon.
POEP Pocket Guide Provides Helpful Tips on HPV Vaccine
TMA's Physician Oncology Education Program has produced a pocket guide that provides physicians with helpful information when talking with patients or their parents about the human papillomavirus (HPV) vaccine.
The guide includes recommendations from the U.S. Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices (ACIP) on who should get the vaccine, as well as patient education points about HPV and the vaccine.
The guide now includes the ACIP's recent recommendation regarding use of the vaccine in boys and young men.
Physicians may get a copy of the pocket guide by e-mailing Cassandra Sanchez or by phoning (800) 880-1300, ext. 1672, or (512) 370-1672.
July 2010 Texas Medicine Contents
Texas Medicine Main Page