What is Gardasil 9? A New HPV Vaccine

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Gardasil 9 Package. Merck

Like the original HPV vaccine known as Gardasil, Gardasil 9 is designed to protect against the most common high and low risk types of HPV. Unlike the original version of Gardasil, it protects against 9 strains of the virus instead of just four. In addition to the four strains that the original Gardasil vaccine protects against, Gardasil 9 adds protection against HPV 31, 33, 45, 52 and 58, which are responsible for approximately 20 percent of cervical cancer.

Scientists suggest that this new vaccine, which was approved by the FDA in December of 2014, may protect against up to 90 percent of cervical cancers. It also addresses recent criticism about whether or not the existing vaccines are racist by targeting two of the five strains of HPV (33, 35, 45, 58, and 68) that cause a significant percentage of cancers in African American women.

Who is Garadsil 9 Approved for?

On December 10, 2014 Garadsil 9 was approved for use in women and girls aged 9 to 26 and men and boys aged 9 to 15. It was approved for the prevention of cervical, vulvar, vaginal, and cancers as well as genital warts.

People who have previously been vaccinated with Gardasil can be safely vaccinated again with Gardasil 9, but they should discuss with their doctor whether doing so is worthwhile.

On February 26, 2015, Gardasil 9 was added to the recommended routine vaccination list for 11-12 year old boys and girls.

How is Garadsil 9 Given?

Gardasil 9 is given in three doses over a six month period. The additional doses are given two and six months after the first dose.

Who Should Not Get Garadsil 9

According to Merck, the company that manufactures the vaccine, people should not get vaccinated with Gardasil 9 if they have ever had an allergic reaction to: a previous dose of Gardasil 9 or Gardasil, yeast, amorphous aluminum hydroxyphosphate sulfate, or polysorbate 80.

The most common side effects reported during the clinical trial were injection site pain, swelling, redness, and headaches. There were very few serious adverse reactions in the initial clinical trials, which included over 13,000 people. This suggests that the safety profile is likely to be similar to the safety profile of the original vaccine.

Note: As with the original vaccine, Gardasil 9 was originally approved for young men and women because that is the population it was tested in. There is no expectation that the vaccine would be unsafe in individuals over the identified ages. It is simply that HPV infection is so common in older adults that it is harder to show vaccine efficacy. I suspect that the vaccine will eventually be available for older men and women who wish to access it, just as the original vaccine was. However, it is unlikely to be covered by insurance.

Sources:

FDA.Gov (2014) FDA approves Gardasil 9 for prevention of certain cancers caused by five additional types of HPV. FDA News Release. Retrieved from http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm426485.htm on 3/13/15

Merck. Gardasil 9 Prescribing Information. Retrieved from http://www.merck.com/product/usa/pi_circulars/g/gardasil_9/gardasil_9_pi.pdf on 3/13/15

Merck Press Room. (2015) Merck’s 9-Valent HPV Vaccine, GARDASIL®9, Recommended by CDC’s Advisory Committee on Immunization Practices for Females Aged 9-26 and Males Aged 9-21. Retrieved from http://www.mercknewsroom.com/news-release/vaccine-news/mercks-9-valent-hpv-vaccine-gardasil9-recommended-cdcs-advisory-committee- on 3/13/15

Vidal AC, Smith JS, Valea F, Bentley R, Gradison M, Yarnall KS, Ford A, Overcash F, Grant K, Murphy SK, Hoyo C. HPV genotypes and cervical intraepithelial neoplasia in a multiethnic cohort in the southeastern USA. Cancer Causes Control. 2014 Aug;25(8):1055-62.

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