Extending the human papillomavirus (HPV) vaccine program through age 45 years would produce small benefits for a steep price, according to new research.
The study, published in the Annals of Internal Medicine
, predicted that extending the vaccine program to adults would reduce diagnoses over 100 years of anogenital warts by 0.4 percentage points, cervical intraepithelial neoplasia of grade 2 or 3 by 0.4 percentage points, cervical cancer by 0.2 percentage points, and noncervical HPV-associated cancer by 0.2 percentage points.
That compares with reductions of 82%, 80%, 59%, and 39%, respectively, over 100 years under the program in effect at the time of the study, which includes routine vaccination at 11 to 12 years, with catch-up vaccination through age 26 years for women and 21 years for men.
The cost of extending the vaccine program were estimated at $830,000 for adults up to age 30 years, $1,843,000 up to age 40 years, and $1,471,000 up to age 45 years.
The study was led by Jean-Francois Laprise, PhD, senior research associate at the Centre de recherche du CHU de Québec–Université Laval in Canada.
Funded by the US Centers for Disease Control and Prevention (CDC), the study used HPV-ADVISE (Agent-based Dynamic model for VaccInation and Screening Evaluation) to evaluate age-specific U.S. data.
The US Food and Drug Administration approved the expanded use
of 9-valent, recombinant HPV vaccine, Gardasil 9, to age 45 last year. The vaccine, introduced in 2014, targets 9 strains of HPV instead of 4 targeted by the previous vaccine.
In June, the CDC presented an overview
of 5 different economic models, including HPV-ADVISE, to the Advisory Committee on Immunization Practices. While the models produced notable differences in cost estimates, they predicted that vaccinating adults over age 26 years would produce small health benefits, according to that review. It predicted that the number needed to vaccinate to prevent one case of disease is about 40 times higher for adults through age 45 years than the current program.
The Advisory Committee on Immunization Practices voted in June
to expand the recommended HPV vaccine catch-up age to 26 years for men, matching that for women, and recommending shared clinical decision-making for the vaccination among adults ages 27-45 years.
The CDC updated HPV vaccination recommendations
in August, noting a minimal public health benefit of vaccinating adults ages 27 to 45 years and recommending shared clinical decision-making because some individuals in that age range might benefit from vaccination.
HPV affects 79 million Americans, predominately in their late teens and early 20s, according to the CDC. About 14 million Americans are infected each year. HPV causes about 35,000 cases of cancer each year, including cervical, anal, oropharyngeal, and penile cancers. About 12,000 women are diagnosed with cervical cancer associated with HPV, about a third of whom will die.
A study published earlier this year found evidence of herd immunity
to oral infections from HPV, noting that rates of oral infections from the types HPV prevented by vaccines fell by 37% among unvaccinated men aged 18-59 years from 2009 to 2016.
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