Should Children Who Have Received the Full Series of HPV4 Vaccine Also Get HPV9?

Paul A. Offit, MD


February 09, 2017

Editorial Collaboration

Medscape &

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Hi. My name is Paul Offit. I am talking to you today from the Vaccine Education Center at The Children's Hospital of Philadelphia.

One question that has come up for us at the Vaccine Education Center is what to do about children who have already received HPV4 vaccine, given that HPV9 is now available. Let's start from the beginning.

The HPV4 (human papillomavirus vaccine that contains 4 serotypes) was first licensed and recommended for girls in 2006. HPV4 contains serotypes 6 and 11, which will prevent about 90% of anal and genital warts. It also contains serotypes 16 and 18, which will prevent about 70% of what causes anal, genital, head and neck, and cervical cancers. In 2010, HPV4 was also recommended for boys.

In 2015, HPV9 became available and is now a two-dose vaccine. HPV9 also contains serotypes 31, 33, 45, 52, and 58, which will pick up another 15% of anal, genital, head and neck, and cervical cancers, increasing the prevention of cancers caused by HPV from 70% to 85% of these cancers.

[With HPV9] you will prevent approximately 3000 more cases of cancer and several hundred deaths. You will go from preventing 25,000-26,000 cases of cancer and 4000 deaths yearly with HPV4, to preventing about 28,000-29,000 cases and several hundred more deaths with HPV9.

Is that of value? If you had an HPV5 vaccine, for example, that contained only five serotypes, and you knew that it could prevent 3000 cases of cancer and several hundred deaths, of course you would use it. So why not use HPV9? The answer is, I think you should. People who have already completed the three-dose HPV4 series should also get two doses of HPV9, separated by at least 6 months.

The problem is that because there are no clear recommendations from the CDC or the American Academy of Pediatrics, there is a question about whether an additional vaccine is going to be covered by insurance companies. This could inadvertently set up a two-tiered system, meaning that the only people who can use the best medical recommendation are those who can afford it.

I hope that helps, and thanks for your attention.


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