Friday, 29 March, 2024
HomePublic HealthVaccine works against most cancer-causing HPVs

Vaccine works against most cancer-causing HPVs

A multinational clinical trial involving nearly 20,000 young women has found that the vaccine Cervarix not only has the potential to prevent cervical cancer, but is effective against other common cancer-causing human papillomaviruses, aside from just the two HPV types, 16 and 18, which are responsible for about 70% of all cases. That effectiveness endured for the study’s entire follow-up, of up to four years.

"The study confirms that targeting young adolescent girls before sexual debut for prophylactic HPV vaccination has a substantial impact on the incidence of high grade cervical abnormalities," said corresponding author, Dan Apter, director, The Sexual Health Clinic, Family Federation of Finland, Helsinki.

The vaccine was extremely effective in young women who had never been infected with HPV. It protected nearly all from HPV-16 and -18, and protected 50-100% against different grades of pre-cancerous transformation of cervical cells caused by other strains of HPV, including up to 100 percent of those with the immediate precursor grade to cancer. The women were followed for up to four years post-vaccination.

The vaccine was distinctly more effective among ages 15-17 than ages18-25, underscoring the value of vaccinating young adolescents, said Apter. The lower efficacy in the oldest age group may result from a larger proportion of women in that age group having had persistent infections at the time of vaccination, he said.

The study is the final report from the Papilloma Trial Against Cancer in Young Adults (PATRICIA), a multinational clinical trial encompassing 14 countries in Europe, the Asia-Pacific region, North America, and Latin America, and it confirms previous reports in this trial. The over-all trial constituted the basis for approval of the Cervarix vaccine in Europe and the US.

While the trial did not investigate the vaccine's efficacy in males, sexually transmitted HPV causes ano-genital and head and neck cancers in both males and females. "The more adolescents are vaccinated, the closer we will be to eradicating high risk HPV viruses," said Apter. "So I think boys should also be vaccinated."

[link url="https://www.asm.org/index.php/journal-press-releases/93377-hpv-vaccine-highly-effectiveagainst-multiple-cancer-causing-strains"]American Society for Microbiology press release[/link]
[link url="http://cvi.asm.org/content/early/2015/01/29/CVI.00591-14.abstract?sid=ef01415e-616b-4dc2-b950-52e343ce66dd"]Clinical and Vaccine Immunology abstract[/link]

MedicalBrief — our free weekly e-newsletter

We'd appreciate as much information as possible, however only an email address is required.