HPV Vaccine (Human Papilloma Virus)
Is the HPV Vaccine Benefits exaggerated?
Experts debated whether marketing (Marketing) Gardasil decision muddy Risk / Benefit
Aug.. 18, 2009 - Merck's Gardasil won the Pharmaceutical Executive 2006 "Brand of the Year" award to "create a market of thin air". But whether the HPV vaccine sold too much?
The accusation came from "special communication" and an editorial published May. 19 of The Journal of the American Medical Association.
The articles say professional medical associations to work with Merck to overstate the ability of a vaccine to prevent cervical cancer - even before studies prove Gardasil can prevent precancerous cervical injuries.
Overselling the benefits of HPV vaccine makes it impossible for parents and young women to judge whether the vaccine risks are worth taking, says editorialist Charlotte Haug, MD, PhD, chief editor of the Journal of the Norwegian Medical Association .
"If he really is the perfect vaccine you will never again think about cervical cancer. But it is effective against two of the strains of the virus, and there are at least 20 strains that cause cancer," said Haug tells WebMD. "It is true these strains cause 70% of cervical cancers, but what happens when we take out these two strains? If you kill the weeds in your lawn, there will always be a hole there. Something will take their place ".
Just because we do not know this does not mean the vaccine is worthless, says Janet Englund, MD, pediatrician infectious disease at Seattle Children's Hospital. Englund chaired the working group on HPV from CDC's Advisory Committee on Immunization Practices (ACIP).
For Englund, it is not merely an abstract opinion.
"I have vaccinated my children," he said. "I take the risks and benefits into consideration, and I think the benefits outweigh the risks".
HPV, human papillomavirus, is a very common infection transmitted through sexual intercourse. Most of the women and men who are sexually active get a virus - often more than once, and often with more than one strain. Normally, the immune system clears the virus. But sometimes he stuck around. Some strains of the virus cause genital warts. Other strains that cause cancer.
Gardasil protects against four of the more than 100 strains of HPV: two strains that cause most cervical cancers, and two strains linked to genital warts. The vaccine is most effective when given to girls before they become sexually active. He can be given as early as age 9 years; CDC recommends it for girls aged 11 and 12 years. The vaccine costs $ 300 to $ 500, but is covered by the U.S. Vaccines For Children program.
Gardasil Oversold by medical groups?
Columbia University researchers, Sheila Rothman, PhD, and David Rothman, PhD, suggests that at least three medical associations have used the funds and other assistance from Merck to create educational materials for doctors rather than specialists promoting Gardasil.
"Doctors may not know that education is not conducted by a group of experts in the field but that it was compiled / written by drug company," said Sheila Rothman tells WebMD.
Stewart Massad, MD, head of ethics for the American Society for Colposcopy and Cervical Pathology - one of the groups mentioned by Rothmans - Rothmans said that although it is true that his group supports the HPV vaccination, they are wrong to say Merck has written their educational materials.
"The HPV vaccine is a revolutionary advance that promises to change the way cervical cancer is preventable," said Massad tells WebMD. "We think our members need to know about it. We seek funding from elsewhere, but we were not able to find a nonprofit or government funding to fill the costs. We express support for Merck on all the materials that we share, and Merck has had no role in writing them. They agree with the concept but was not allowed to have any input on the material developed ".
Society of Gynecologic oncologists said in a statement that was passed on WebMD that the materials are not prejudiced (biased). The third group is called by Rothmans, the American College Health Association, did not respond to WebMD's request for comment.
But Rothmans article suggests that these associations overemphasized the risk posed by HPV and overstated the scientific evidence supporting the ability of Gardasil to prevent cancer.
"The reality is that the majority of HPV infections are asymptomatic; most of that goes away by itself", says Rothman. "Only 10% of infections go on to become lesions. Yes, we have the causative agent (the cause) and disease. But that is not a straight line to reach there. And what did the company is to create a straight line and get the organization -organization goes along with it and legitimize it ".
Richard M. Haupt, MD, MPH, Merck's executive director of clinical research, Rothman said is wrong.
"There is very good evidence regarding the line leading from HPV infection to cancer". Haupt tells WebMD. "If you do not get an infection with HPV strains that cause cancer, you do not get cervical cancer".
Massad said the line between HPV infection and cervical cancer may be vague - but it is the line everything.
"Most women who get HPV never be at risk for cervical cancer - but we do not mempunyi way to tell who is at risk and who is not at risk," said Massad. "It seems that it is better to vaccinate widespread than not take any action at all".
Haug said the approach ignores the cost of vaccines, and risk of the vaccine in women who may never get cervical cancer.
HPV vaccine, Pap Screens, and Cervix Cancer
Rothman noted that if women receive the vaccine or not, they still need regular Pap screening to look for early signs of cervical cancer. Screening cut their risk of cervical cancer, and thus cuts the benefits of HPV vaccination.
Haug notes that American women who get cervical cancer are those with the least access to health care. Those who get regular Pap tests, she says, are likely to get cervical cancer even if they do not get vaccinated against HPV.
"We already have ways to prevent cervical cancer - it is the main point, at least for those of us fortunate enough to have health care and use. So this can be prevented without a vaccine," said Haug.
This is not entirely true, says Haupt.
"While the Pap screening is a crucial intervention, it is not perfect. Not all women get a Pap test, and not all women who get Pap tests would have detected his injuries," said Haupt on WebMD. "And even with a 50-year Pap test, we saw 30 cases of cervical cancer a day in America. Vaccination is another tool in conjunction with Pap screening will contribute to the prevention of cancer. No one works as well without the other".
"We still have people who die of cervical cancer here in America," Englund said. "It is easy to say we can prevent cervical cancer with Pap screening, but these people are not getting Pap screens: minority women, our indigenous people, people who are poorer. So when you talk about the risks and benefits, people must realize that some do not have the benefit of having an excellent health care that I enjoy because I have health insurance. But they still possessed the risk of cervical cancer ".
Gardasil Risks
The CDC report - which appears on the same issue of The Journal of the American Medical Association - summarize adverse events associated with Gardasil of the consent (permission) in June 2006 to December 2008.
The report found only one major safety issue worthy of further study: There may be a higher number than that expected from blood clots in women who had received the vaccine.
Study leader Barbara A. Slade, MD, medical officer at the CDC, noted that the reports do not prove the link between vaccines and adverse events. These reports, however, point to the potential risks that require further study.
"This is something worth to be noticed", said Slade tells WebMD. "Now almost all the people with blood clots have one of the known risks: estrogen birth control, obesity, one of the genetic mutations that put you at risk. Most have one if not more than one of these risks ".
Further studies will be needed to show whether blood clots are actually caused by vaccines; these kinds of studies have been being on the way.
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