For immediate release
April 8, 2005
Contact: Bob Beard
(434) 982-4490
reb8e@virginia.edu
NEW VACCINE TO TREAT CERVICAL CANCER AND GENITAL WARTS SHOWS PROMISE, SAYS PATHOLOGIST AT UNIVERSITYOF VIRGINIA HEALTH SYSTEM
A vaccine against four of the human viruses that cause most cervical cancers and genital warts could reduce infection and disease by more than 90 percent, according to the results of a randomized clinical trial published in the online edition of the British medical journal The Lancet Oncology.
A worldwide team of scientists, including Dr. Mark H. Stoler, a pathology professor at the UVa Health System, conducted a trial to test the effectiveness of a vaccine targeting four types of human papillomavirus (HPV) associated with 70 percent of cervical cancers and almost all cases of genital warts. The types targeted by the vaccine are HPV 16 and 18 (cervical cancer) and HPV 6 and 11 (genital warts.)
“After the results of this trial, all of the investigators are optimistic that a successful vaccine against cervical cancer and genital warts can be brought to market within three or four years,” Stoler said. “This study shows almost perfect efficacy.”
Investigators first recruited 1,158 healthy women aged 16 to 23 into the study. The women were not pregnant, had no previous abnormal Pap smears and reported a history of four or fewer partners. Then, investigators randomly assigned 277 women to the vaccine and 275 to a placebo. The women were injected with three doses of the vaccine within a six-month period and then underwent regular gynecological examinations, sampling for HPV DNA, Pap smears and biopsies as medically-indicated.
The incidence of persistent infection or disease with HPV fell by 90 percent in women who were assigned the vaccine compared with those assigned the placebo. The vaccine was 100 percent effective against cervical intraepithelial neoplasia (precancerous lesions) and genital warts caused by the vaccine-specific HPV types. There were no vaccine related serious adverse events.
The authors suggest that universal HPV vaccination might be most effective if implemented in 10 to13 year olds, who are not sexually active and are likely to be HPV negative. Large-scale trials of the vaccine are currently underway. “In developing countries that have not implemented screening programs for cervical cancer, a universal HPV vaccine could substantially reduce the incidence of the disease,” said Dr. Luisa L. Villa of the Ludwig Institute for Cancer Research in Sao Paulo, Brazil.
Up to 70 percent of sexually active women will become infected with HPV during their lifetime. The virus causes around 470,000 cases of cervical cancer each year around the world. In the U. S., over 10,000 new cases of cervical cancer are predicted to occur in 2005, according to The American Cancer Society. This year, over 3,700 women will die of the disease. HPV infections are also responsible for genital warts in 1 to 2 percent of young adults. Genital warts can cause sexual dysfunction and treatment is painful and expensive.
The study was funded by the Merck & Co., Inc., the manufacturer of the vaccine, and can be found on the web at: http://oncology.thelancet.com/
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