New data suggest that HPV vaccination catch-up programs may be warranted, but the cost-effectiveness of these programs past age 22 years is uncertain.
“The cost-effectiveness of vaccinating beyond this age becomes more uncertain as the upper vaccine age limit is influenced by several decisive factors, most notably, the level of vaccine protection among women with previous exposure to vaccine-targeted HPV types,” researchers from the University of Oslo, Norway, and the Harvard School of Public Health, wrote in the Journal of Infectious Diseases.
The researchers used epidemiologic data on HPV prevalence and the incidence of HPV-related conditions in Norway to calibrate an HPV transmission model. They projected the costs and the benefits when the upper vaccination age limit was modified to 20, 22, 24 or 26 years. They also evaluated the vaccine’s protection among women with prior HPV infections, cost, coverage and HPV immunity.
They found that vaccination benefits decreased as the upper age limit increased. When looking at HPV-16/18 incidence among women previously exposed, and assuming the “lower” bound vaccine protection, girls aged 20 at the time of catch-up vaccination would experience a 22% higher reduction in HPV-16/18 incidence compared with routine vaccination at age 12. But girls aged 26 at time of catch-up vaccination would experience only a 4.2% higher reduction.
Looking at cost-effectiveness, they found that at a market price of $150 per dose, all catch-up programs yielded ratios of more than $83,000 per quality-adjusted life year (QALY) gained, which is the common benchmark for cost-effectiveness in Norway, according to the researchers. But when considering the benefits for all male and female HPV-related diseases, the cost-effectiveness of a 1-year catch-up program up to age 20 fell to $53,500 per QALY gained.
“Policies surrounding the implementation of a delayed temporary catch-up program are time-sensitive as initially vaccinated cohorts will soon reach the upper age limit of 26,” the researchers wrote. “Moreover, as we demonstrate in this analysis, the incremental benefit of vaccinating older women decreases with age. For countries assessing whether to implement a temporary catch-up program, the maximum value achieved by these decisions will only decrease as decisions are delayed.”
Disclosure: The researchers report no relevant financial disclosures.