Optimal allocation strategies for HPV vaccination introduction and expansion in China accommodated to different supply and dose schedule scenarios: a modelling study

Abstract

A key barrier to cervical cancer elimination in China is low human papillomavirus (HPV) vaccine uptake, which is limited by supply constraints, high prices, and restriction to two/three-dose schedule. We explored optimal vaccination strategies for maximizing health and economic benefits accommodated to different supply and dose schedules. We evaluated different HPV vaccine strategies under 4 scenarios with different assumptions about vaccine availability and dose schedules. Each strategy involved different vaccine types, target ages, and modes of delivery. We used a previously validated transmission model to assess the health impact (cervical cancer cases averted), efficiency (number of doses needed to be given to prevent one case of cervical cancer [NND]), and value for money (incremental cost-effectiveness ratio [ICER] and return on investment [ROI]) of different strategies in Chinese females over a 100-year time horizon. All costs are expressed in 2021 dollars. We adopted a societal perspective and discounted quality-adjusted life-years (QALYs), costs and benefits by 3% annually for cost-effectiveness analysis and ROI calculation. In a supply-constrained and on-label use scenario, compared with no vaccination, two-dose routine vaccination of 14-year-olds would be the optimal, cost-saving strategy for a future national program (NNDs: 150-220, net cost saving: $15 164 million-$22 034 million, ROIs: 7-14, depending on vaccine type). If the one-dose schedule recommended by WHO is permitted in China, then reallocating the second dose from the routine cohorts to add a catch-up vaccination at 20-year-olds would be the most efficient strategy (NNDs: 73-107), and would be cost-saving compared with routine one-dose vaccination only (net cost saving: $4127 million-$6035 million, ROIs: 19-37). When supply constraints are lifted, scaling up vaccination in older females to 26 years could further expand the health benefits and still be cost-saving compared to maintaining the optimal vaccination strategy in the supply-constrained context. Our study provides timely evidence for the current and future HPV vaccination strategy planning in China, and may also be of value to other countries with supply and dose restrictions. Bill & Melinda Gates Foundation; CAMS Innovation Fund for Medical Sciences (CIFMS).