HPV Vaccination at Age 45: Limited Benefit with Shared Decision-Making Approach
The HPV vaccine is FDA-approved for use through age 45, but routine vaccination is NOT recommended for adults aged 27-45 years; instead, shared clinical decision-making should guide vaccination decisions in this age group, recognizing that most individuals will derive minimal benefit due to prior HPV exposure. 1
Guideline-Based Recommendations by Age
Ages 27-45 Years: Shared Clinical Decision-Making Required
ACIP explicitly does NOT recommend routine catch-up vaccination for all adults aged 27-45 years, but acknowledges some individuals not adequately vaccinated might be at risk for new HPV infection and could benefit from vaccination. 1
The FDA expanded approval for 9-valent HPV vaccine (Gardasil 9) to ages 9-45 years in October 2018 based on clinical trial data in women aged 24-45 years and bridging immunogenicity/safety data in men. 1
HPV vaccines are NOT licensed for use in adults over age 45 years. 2
American Cancer Society Position: Does NOT Endorse Vaccination Ages 27-45
The ACS explicitly does not endorse the shared clinical decision-making recommendation for adults aged 27-45 years due to low effectiveness, minimal cancer prevention potential, burden of decision-making, and lack of sufficient guidance on patient selection. 1
Vaccination of adults through age 45 was estimated to prevent only an additional 0.5% of cancer cases, 0.4% of cervical precancer cases, and 0.3% of genital warts cases over the next 100 years compared to vaccination through age 26. 1
The number needed to vaccinate (NNV) to prevent one cancer case increases dramatically: 202 for the current program versus 6,500 for extending to age 45 years. 2
Why Effectiveness Decreases Dramatically After Age 26
Natural History and Prior Exposure
Most new HPV infections occur in adolescents and young adults, with HPV acquisition generally occurring soon after first sexual activity. 1
Most sexually active adults have already been exposed to HPV, though new infections can occur with new sexual partners. 1, 2
HPV vaccines are prophylactic only—they prevent new HPV infections but do NOT treat existing infections or HPV-related diseases. 2, 3
HPV vaccination effectiveness decreases dramatically by age 18 years with minimal benefit noted by age 20-21 years. 1
Immunogenicity Considerations
Vaccine efficacy was remarkably high among young women who were HPV seronegative before vaccination, but lower among women regardless of HPV DNA status when vaccinated and among adult women. 3
No clinical antibody test can determine whether a person is already immune or still susceptible to any given HPV type. 2
Specific Factors Favoring Vaccination in Ages 27-45
If pursuing shared clinical decision-making, consider vaccination for individuals with:
New sex partners or anticipating new partners in the future, as new partners at any age increase risk for acquiring new HPV infections. 2
Men who have sex with men (MSM), who may especially benefit from prevention of condyloma and anal cancer. 2
Immunocompromised status (though vaccine effectiveness might be lower in these individuals). 2
Persons NOT in long-term, mutually monogamous relationships (as these individuals are not likely to acquire new HPV infections). 2
Critical Caveats and Pitfalls
Communication Concerns
The shared decision-making recommendation may have unintended consequences by shifting focus from cancer prevention back to sexual behavior, potentially stalling progress in adolescent vaccination rates. 1
Parents of 9-12 year-olds (often aged 27-45 themselves) may receive conflicting messages: their children's providers emphasize cancer prevention while their own providers discuss sexual behavior considerations. 1
Dosing Requirements for Adults
Adults aged 15 years or older require a 3-dose schedule administered at 0,1-2, and 6 months (unlike the 2-dose schedule for those vaccinated before age 15). 2
Approximately 53% of individuals aged 27-45 who initiate vaccination do not complete the series, representing significant waste of resources. 4
Does Not Replace Screening
- HPV vaccination does NOT change cervical cancer screening recommendations—screening must continue per guidelines regardless of vaccination status. 2
Vaccine Options Available
9-valent HPV vaccine (Gardasil 9) is the only HPV vaccine currently distributed in the United States as of late 2016. 1
The 9-valent vaccine protects against HPV types 6,11,16,18,31,33,45,52, and 58, covering the majority of HPV-associated cancers (caused by HPV 16/18) plus additional high-risk types. 1
Bottom Line for Clinical Practice
For a 45-year-old individual, vaccination may be technically permissible but offers minimal public health benefit. 1 The decision should involve frank discussion about:
- Prior sexual exposure likely means protection against most or all vaccine-type HPV already exists through natural infection
- Future risk depends entirely on likelihood of new sexual partners
- Cost-effectiveness is poor compared to vaccinating younger individuals
- Three doses are required with significant non-completion rates in this age group 4
The priority must remain vaccinating adolescents aged 9-12 years and catch-up vaccination through age 26 years, where effectiveness is proven and substantial. 1