Will cervical screening remain cost-effective in women offered the next generation nonavalent HPV vaccine? Results for four developed countries.

A next generation nonavalent human papillomavirus (HPV) vaccine ("HPV9 vaccine") is being introduced in several countries. The aims of this study were to evaluate whether cervical screening will remain cost-effective in cohorts offered nonavalent vaccines and if so, to characterize the optimal number of screening tests. We used a dynamic model of HPV vaccination and cervical screening to evaluate the cost-effectiveness of strategies involving varying numbers of primary HPV tests per lifetime for cohorts offered the nonavalent vaccine as 12 year-olds. For each of four countries-the USA, New Zealand (NZ), Australia and England-we considered local factors including vaccine uptake rates (USA/NZ uptake ∼50%; Australia/England uptake >70%), attributable fractions of HPV9-included types, demographic factors, costs and indicative willingness-to-pay (WTP) thresholds. Extensive probabilistic sensitivity analysis was performed. We found that, in the USA, four screens per lifetime was the most likely scenario, with 34% probability of being optimal at WTP US$50,000/LYS, increasing to 84% probability at US$100,000/LYS. In New Zealand, five screens per lifetime was the most likely scenario, with 100% probability of being optimal at NZ$42,000/LYS, given the assumptions used. In Australia, two screens per lifetime was the most likely scenario, with 62% probability of being optimal at AU$50,000/LYS. In England, four screens per lifetime was the most likely scenario, with 32% probability of being optimal at GB£20,000/LYS, increasing to 96% probability at GB£30,000/LYS. We conclude that some cervical screening will remain cost-effective, even in countries with high vaccination coverage. However, the optimal number of screens may vary between countries.