Gardasil 9 Effectively Stops 90% Of Cancers Caused By HPV In Girls and Boys
MOMS AND DADS TAKE NOTE
The newest HPV vaccine safely and effectively prevents at least four different kinds of cancer in the population recommended to receive it, according to a study in Pediatrics today. Gardasil 9, manufactured by Merck, protects against nine strains of the human papillomavirus, an infection transmitted through direct or indirect contact with the genitals of an infected person.
Researchers tested the vaccine in preteens and teens, those that the CDC’s Advisory Committee on Immunization Practices recommends receive the vaccine, to ensure the vaccine works at least as well as it did in those in earlier clinical trials. The verdict? It works even better.
“With little kids, preteens and teens, you have to show that the antibodies are as good or better than in adult women, whom we know efficacy data in,” said Dr. Stanley Block, a pediatrician in Bardstown, Kentucky, and a co-author of the study, which was funded by Merck. “This vaccine is critically important because we’re talking about four cancers we know absolutely for sure that it prevents – cervical, vulvar, anal and vaginal – and about two thirds of all oral cancers that it should prevent.”
In the study, researchers gave 3,066 boys and girls, ages 9 to 15, a three-dose series of the HPV-9 vaccine. The second dose was administered a month after the first, and the third dose at six months later. A month after the third dose, more than 99% of the participants had sufficient antibody levels for all nine strains included in the vaccine.
At a follow-up two and a half years later, the participants’ antibody levels were still going strong, with no reason to suspect they will wane.
“Studies for the quadrivalent [four-strain] and bivalent [two-strain] vaccine have followed study participants for about eight to ten years to date and have found no evidence of waning protection,” said Dr. Lauri Markowitz, of the Division of STD Prevention at the CDC, who was not involved in this study.
The most current study on the duration of Gardasil’s effectiveness, published last year, shows that the vaccine continues to be effective eight years after the last dose. Block, who coauthored that study as well, said new data not yet published will show that the protection continues beyond eight years, too.