Posted on 09/20/2007 7:44:49 AM PDT by Alter Kaker
Merck Study Shows Partial Protection Against Additional Cancer-Causing Strains
A study by the company that makes Gardasil, a vaccine that protects against cervical cancer, suggests it may be even more effective than previously thought.
The vaccine, manufactured by Merck, had previously been thought to only protect against 70 percent of cervical cancer caused by viruses. However, the new research indicates that it may also have at least some effect against viral strains that cause the other 30 percent.
The new data was presented this week by Merck at the Interscience Conference on Antimicrobial Agents and Chemotherapy.
The finding was an unexpected one, says study investigator Dr. Darron Brown, professor of medicine, microbiology and immunology at Indiana University School of Medicine in Indianapolis.
"I was surprised at the high degree of cross protection pleasantly surprised," he said.
And doctors unaffiliated with Merck agree that the research is promising.
"The data are very encouraging because they show cross protection against infection and disease caused by other HPV types that are not included in the vaccine," said Dr. Jessica Kahn, associate professor of pediatrics at Cincinnati Children's Hospital Medical Center in Ohio.
The vaccine protects against cervical pre-cancer by priming the body's defenses against a sexually transmitted virus called the human papilloma virus (HPV). It specifically protects against four strains of the virus strains 16 and 18, which lead to cervical pre-cancer, and strains 6 and 11, which cause genital warts.
What researchers found in the new study was that the vaccine may also offer partial protection against pre-cancerous lesions caused by 10 additional strains of HPV.
This could be especially important in preventing long-lasting infections, which are more likely to eventually lead to cancer.
"Seventy-five to 90 percent of infections go away," said Dr. Diane Harper, study investigator and professor of obstetrics and gynecology at Dartmouth Medical School in Lebanon, N.H. "What we really want to prevent are persistent infections those infections that stay and don't clear on their own."
At the heart of the new finding is the concept of "cross protection," which means that although the vaccine is designed to protect against lesions caused by a few specific types of HPV, it can also have some effect, albeit a smaller one, on other strains that are closely related.
"This high degree of cross protection & provides an extra measure of protection for young women," said Brown.
The new findings may be even more important in other parts of the world where cervical cancer is more prevalent.
"In many developing regions, cervical cancer is the No. 1 cancer," said Kahn. "About half a million women around the world get cervical cancer, so it has tremendous public health impact."
The additional strains studied include HPV strain 52, which is more prevalent in some parts of Asia, notes Dr. Kevin Ault, study investigator and associate professor of gynecology and obstetrics at Emory University in Atlanta.
Ault says the new findings may make it easier for many to justify the cost of the vaccine, which runs at around $150 per dose.
"You really get a little more bang for your buck; you get some modest protection against other [strains] based on this data," said Ault. "Seventy percent [of cervical cancer] is caused by strains 16 or 18, so that leaves a 30 percent window that we've been worried about & so you might be able to get at some of those other cases through this cross-protection effect."
Despite the new findings that show increased protection, doctors point to an important limitation of the vaccine it is only 39 percent effective against lesions caused by these other strains of HPV. The majority of that efficacy was seen in just two of the other 10 strains, notes Harper.
However, physicians are still optimistic about the new findings and hope additional coverage will eventually help reduce cervical cancer rates.
"The vaccine is very safe and effective in preventing [cervical pre-cancer] caused by the two most common cancer-causing HPV types," said Brown. "[Women] should also know that they can have this extra measure of protection against other types."
But Harper notes that there is no substitute for other means of prevention and early detection.
"Even with the coverage of more types & people that have Gardasil can still get cancer," she said. "Pap screening is still important."
Copyright © 2007 ABC News Internet Ventures
and what side effects does this vaccination heard. Light side effects like being not able to conceive? To sudden drop death?
What are you talking about?
all medicines have side effects. all vaccines have side effects.
doesn’t effect all, but if you are within the 3% who drop dead, the govt, and labs think that is just fine.
You actually know of a vaccine that causes 3 percent who take it to drop dead?
I didn’t think so.
Who has dropped dead because of Gardasil? I'm aware of controled tests in over 11,000 girls and women. Of those 11,000 there wasn't a single serious adverse reaction. So I'm honestly not sure what you're talking about.
3% drop dead????
is it more effective or will it lead to stronger virii?
it will kill off the week strains but eventually a strain will not be killed, given that it is a virus, how long before it outgrows the cure?
Gee a company study about a company product that shows how good it is??
Shocking!
Had small pox recently? Vaccines can work in the long run to eliminate diseases, all the more so if they're administered correctly. Gardasil will not eliminate HPV any time soon (when a majority of the population has it), but it might lower incidence of cervical cancer.
Just because it's a company study doesn't mean it's invalid. Merck is publishing their research including their methodology. If it later turns out that the research is fraudulent then the researchers responsible will never be able to work again anywhere... I think that's a disincentive for fraud.
Great news if true. I think this should be an option for everyone not something mandated.
I think you need to actually read that study.
You can hardly count the people who took placebos in your total for adverse reactions!
The actual paper is much less conclusive than you might think. It also has NO real long term data.
Remember, thalidomide was a great drug that didn’t bother the people taking it. Their babies was another thing!
I'm glad that I have boys. Will let someone else be the guinea pigs for long term effects, here.
This is certainly worth posting, but I suspect it is more in the nature of a desperate press release than a scientific study.
After Merck failed to sell its vaccine by stealth agreement with politicians to force school children to take it whether the parents liked it or not, they had to come up with some other way to sell this drug.
Since planned parenthood and the teachers’ unions have managed to install sex-ed classes in our public schools that teach little kids that all sex is good, provided that they wear condoms, there has been a huge outbreak of unwanted pregnancies, abortions, and assorted STDs. There was nothing like it before Planned Parenthood started doing its work.
The solution to the problem is not more AIDS drugs and STD drugs, but a return to moral values and abstinence. Otherwise, STDs will continue to spread and grow more virulent.
Well, you're wrong. There actually is a scientific study here, and it's being published in a well-respected peer-reviewed scientific journal. You're completely right that this does have a public-relations angle, and the study was conducted by bona fide researchers hired by Merck as a means of promoting their product, but in no way should that impeach the credibility of the results.
The solution to the problem is not more AIDS drugs and STD drugs, but a return to moral values and abstinence. Otherwise, STDs will continue to spread and grow more virulent.
I don't see this as an either/or. HPV and cervical cancer were around and killing long before Planned Parenthood or MTV. In fact, incidence of cervical cancer has declined dramatically over the last 100 years.
Absolutely... But.... I am really torn on this one. I got HPV from my husband. I had not had sex with anyone else or him until we were married. He was raised a bit differently and converted to the same faith as me before we met and got married. I practiced abstinence and still got it.
Ah yes. More "Take our drug or die" propaganda.
Genital HPV Infection - CDC Fact Sheet
All types of HPV can cause mild Pap test abnormalities which do not have serious consequences. Approximately 10 of the 30 identified genital HPV types can lead, in rare cases, to development of cervical cancer. Research has shown that for most women (90 percent), cervical HPV infection becomes undetectable within two years. Although only a small proportion of women have persistent infection, persistent infection with "high-risk" types of HPV is the main risk factor for cervical cancer.
A Pap test can detect pre-cancerous and cancerous cells on the cervix. Regular Pap testing and careful medical follow-up, with treatment if necessary, can help ensure that pre-cancerous changes in the cervix caused by HPV infection do not develop into life threatening cervical cancer. The Pap test used in U.S. cervical cancer screening programs is responsible for greatly reducing deaths from cervical cancer. For 2004, the American Cancer Society estimates that about 10,520 women will develop invasive cervical cancer and about 3,900 women will die from this disease. Most women who develop invasive cervical cancer have not had regular cervical cancer screening.
HPV is a common virus. In 2005 the Centers for Disease Control and Prevention (CDC) estimated that 20 million people in the United States had this virus. There are many different types of HPV. Some cause no harm; others can cause diseases of the genital area. For most people, the virus goes away on its own. When the the virus does not go away, it can develop into cervical cancer, precancerous lesions, or genital warts, depending on the HPV type.
The cervical cancer death rate declined by 74% between 1955 and 1992. The main reason for this change is the increased use of the Pap test. This screening procedure can find changes in the cervix before cancer develops. It can also find early cancer in its most curable stage. The death rate from cervical cancer continues to decline by nearly 4% a year.
Yes, life can be unfair sometimes. On the other hand, if your husband hadn’t probably been misled when he was young by the fallout from the Cultural Revolution of the 60s, and probably miseducated by public schools, it might not have happened.
Haven’t had scarlet fever, either. These diseases were all eradicated by better hygienic habits and more reliable water supplies. There is little benefit to vaccines, and tremendous long-term side-effects that we are just now beginning to realize (e.g. autism)
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.