2nd Cervical Cancer Vaccine on the Way?
Study Shows Cervarix Protects Against Virus That Can Cause Cervical Cancer
The newly reported findings were published in the latest online issue of the journal Lancet.
They represent an interim analysis from Glaxo's ongoing international trial evaluating the effectiveness of Cervarix.
A total of 18,644 women from 14 countries were included in the trial. All of the women were between the ages of 15 and 25 at study entry.
Young girls who are not yet sexually active or who have just become sexually active are considered the target group for vaccination.
The FDA approved Gardasil for girls and women aged 9 to 26, but Merck is testing the vaccine in boys because men get genital warts and pass HPV infection to their partners.
In the Cervarix trial, about half the women received the three-dose immunizations with the HPV vaccine and half were not vaccinated against HPV.
After an average follow-up of 15 months, the vaccine was found to be 90.4% effective against precancerous cervical lesions caused by HPV-16 and HPV-18.
When researchers further analyzed the lesions they identified, none occurring in the cervical cancer vaccine recipients were found to be caused by the two HPV types, indicating 100% effectiveness, Tursi says.
Jorma Paavonen, MD, who is leading the ongoing international trial, tells WebMD that the interim results are better than he would have expected.
The women in the study will be followed for four years. Women participating in other studies of the vaccine have been followed for just over five years, with little evidence of waning protection, he says.
"It is too early to say if boosters will be needed at 10 years or 15 years, but it looks like protection is lasting" he says.
Cervical Cancer Protection for All
An editorial accompanying the study points out that the public health impact of HPV vaccination is still unclear.
"Certainly vaccinated women will still require cervical screening [Pap tests] and appropriate follow-up," write Jessica Kahn, MD, and Robert Burk, MD. Kahn and Burk also questioned whether the women who need a cervical cancer vaccine most will get it.
"Poverty is strongly associated with high-risk HPV infection and cervical cancer," they write. "If those who live in poverty cannot access a highly effective intervention such as HPV vaccines, disparities could worsen dramatically."
Tursi tells WebMD that Glaxo has been committed to making its vaccines available to those who can least afford them.
"Glaxo delivers 80% of vaccines to the developing world. We have a strong commitment to the developing world," he says. "And within the U.S. in those areas that will require increased attention, we are poised to provide that."