As discussed in the April 2015 Vaccine Update “News and Views” article, the Advisory Committee on Immunization Practices (ACIP) charter has changed over the years, such that current recommendations are not only informed by the health outcomes of a vaccine, but also its potential economic burden. Two recent decisions by the ACIP deserve attention in light of the current approach to vaccine recommendations. The previous article discussed the details surrounding the meningococcal serogroup B vaccine, so this one will look at the new human papillomavirus vaccine, HPV-9.
A closer look at the HPV-9 vaccine recommendation
Previously available human papillomavirus (HPV) vaccines protect against two of the most common causes of cervical cancer, types 16 and 18, and one of the vaccines, Gardasil®, additionally protects against two common types of genital warts, types 6 and 11. Both vaccines have been recommended for girls at 11-12 years of age, and one, Gardasil, is recommended for boys at 11-12 years of age. Both vaccines require three doses with the second dose given one to two months after the first, and the third dose given six months after the first.
We know these vaccines are safe, and they are preventive (not therapeutic), meaning that it is important to build immunity prior to exposure to the strains in the vaccines. If everyone eligible to be vaccinated gets existing HPV vaccines, we will prevent about 26,000 cases of cervical cancer in the U.S. every year.
The new HPV-9 vaccine protects against five additional strains of HPV (strains 31, 33, 45, 52, and 58) when compared with the existing quadrivalent version of the same name. These five additional strains should protect against an estimated 4 to 18 percent of the various cancers caused by some HPV types, meaning that we could prevent an additional 4,000 cases of HPV-associated cancers throughout the U.S. annually if we use the vaccine in the eligible population:
- Additional 4 percent each of anal cancers and oropharyngeal cancers in males
- Additional 9 percent each of oropharyngeal cancers in females and penile cancers
- Additional 11 percent of anal cancers in females
- Additional 14 percent of vulvar cancers
- Additional 15 percent of cervical cancers
- Additional 18 percent of vaginal cancers
Despite this additional protection, the ACIP recommendation in February 2015 did not express a preference for use of HPV-9. The current recommendation is that the HPV-9 vaccine can be used instead of HPV-2 or HPV-4 in females and in place of HPV-4 in males. The vaccine can be used for the complete series or to complete dosing that was already started with one of the previously existing versions. So what does this mean for healthcare providers trying to decide which vaccine to use? And what does it mean for the girls, boys, young men and young women who may be vaccinated with versions of this vaccine that do not offer the broadest protection available?
Understanding and interpreting vaccine recommendations in the current ACIP climate
Healthcare providers who offer vaccines often already successfully navigate the gray area between state requirements and federal recommendations. And, historically, for the most part, they could look to the U.S. Centers for Disease Control and Prevention (CDC) as well as professional organizations such as the American Academy of Pediatrics (AAP), the American Academy of Family Physicians (AAFP) or the American College of Obstetricians and Gynecologists (ACOG) for guidance related to the best health practices for their patient base — even if state laws were lacking or lagging in getting children vaccinated with newer products.
The failure of the ACIP to express a preference for HPV-9 over the other products means there will be healthcare providers who will not offer HPV-9 to an adolescent or teen whose future might include HPV-associated cancer caused by HPV 31, 33, 45, 52 or 58. These healthcare providers may never know, but by definition, statistically it will happen.
Indeed, other factors, may also complicate decisions by healthcare providers. First, vaccines that are not recommended may not be covered by insurance and the provider’s patient base may not be able to afford the vaccine. Second, even if providers decide to offer these vaccines and have a patient base capable of paying for them, will they get enough “takers” to not lose money on expired doses? This is probably more of an issue with the meningococcal serogroup B vaccine than the HPV vaccine since the HPV-9 version can replace the existing versions for general recommendations. Finally, these recommendations also set the stage for additional, complex communications with parents and families around vaccines. Because now in addition to addressing the vast array of vaccine safety concerns and the existing complex schedule, providers who choose to offer HPV-9 to individuals previously vaccinated with HPV-2 or HPV-4 will need to educate about the lack of these vaccines on the recommended schedule. Given these complexities, it is likely that these newer vaccines will suffer a lack of widespread use ultimately resulting in unnecessary cases of disease.