After losing her mother to breast cancer, Bleu Harper has watched both of her mother's sisters battle cancer as well. And it gives her a sense of foreboding.
"I think it's only a matter of time," said the 23-year-old Augusta State University student. So she had a powerful personal reason for wanting to participate in a vaccine study against a virus that causes half of all cervical cancers. She couldn't have guessed how well it would turn out.
Researchers are hailing it as the first successful vaccine against a form of cancer that kills more than 300,000 women a year worldwide. In findings published today in the New England Journal of Medicine, researchers report that none of the women who were vaccinated against human papillomavirus strain 16 contracted HPV in the following two years.
"A lot of us were dumbfounded because we didn't expect 100 percent (protection)," said Medical College of Georgia researcher Daron Ferris, who was the principal investigator for the local arm of the nationwide study. "Some individuals could still acquire the infection, but this is truly amazing. This is the first vaccine to prevent a cancer, and it will be quickly implemented, I'm sure."
Human papillomavirus is among the most prevalent sexually transmitted viruses, and some estimate there is an 80 percent chance of being infected at least once during a lifetime, Dr. Ferris said. Most strains don't cause much damage and most people with a functioning immune system will get rid of the virus eventually, he said. But some strains, such as types 16 and 18, cause changes in cells that can lead to cancer. Dr. Ferris is testing a vaccine against those two strains and the two most likely to cause genital warts.
"The combination of both (types) 16 and 18 will likely take care of 70 to 75 percent of all cervical cancer," Dr. Ferris said. "Genital warts are a nuisance to patients but also a burden on the health care system."
About 50 million women get Pap smears annually in the U.S. and there will be about 13,000 cervical cancer cases and 4,100 deaths this year, said Debbie Saslow, the director of breast and cervical cancer programs for the American Cancer Society. It is a different story in other countries where the tests are rarely done, if they are even available, and there is much more cervical cancer, she said.
"In the world, it is a huge problem - it is probably the No. 1 cancer killer of women," Dr. Saslow said. "The vaccine, I think, will have the biggest impact in countries that don't have screening. But it still has the potential to have a pretty big impact here based on the number of women who get screened and the number of women who require follow-up tests."
The vaccine used in the U.S. will likely be another form of the vaccine that combines other strains of HPV, Dr. Saslow said, such as the one Dr. Ferris is testing.
Next month, Dr. Ferris will begin a study offering the vaccine to boys and girls ages 10 to 15 to see whether they will develop antibodies from the vaccine. One drawback to the vaccine is that there is no evidence it will work on those previously infected with strain 16, Dr. Ferris said, and in the three to five years it will take to become commercially available many young people will probably contract HPV, he said.
"I think it would behoove parents and young adults to seriously consider taking the opportunity" to enter the study, Dr. Ferris said. "This is associated with a true killer."
The vaccine is also available for women ages 16-23 who have never had an abnormal Pap smear.
Because it is a double-blind study, Ms. Harper doesn't know whether she got the vaccine or the placebo. But after hearing the results Wednesday, she said, "I'm hoping it was the vaccine now."
Reach Tom Corwin at (706) 823-3213 or firstname.lastname@example.org.
|The Medical College of Georgia is conducting clinical trials on a vaccine to prevent infection by certain strains of the human papillomavirus. One part of the study is for girls and women ages 16-23 who have not had HPV or an abnormal Pap smear. Another part of the study is for boys and girls ages 10-15. For more information, call 721-2535.|