Health and economic benefits of single-dose HPV vaccination in a Gavi-eligible country

Emily A Burger,Nicole G Campos,Stephen Sy,Catherine Regan,Jane J Kim

doi:10.1016/j.vaccine.2018.04.061

Abstract

BackgroundAlthough guidelines for prophylactic human papillomavirus (HPV) vaccination recommend two doses for girls ages 9–14 years, several studies have demonstrated similar protection with one dose. Our objective was to evaluate the long-term health and economic impacts of routine one-dose HPV vaccination compared to (1) no vaccination and (2) two-dose HPV vaccination in a low-income country. MethodsWe used a three-tiered hybrid modeling approach that captured HPV transmission, cervical carcinogenesis, and population demographics to project long-term health and economic outcomes associated with one-dose HPV vaccination (assuming 80% efficacy against HPV-16/18 infections under three waning scenarios) and two-dose HPV vaccination (assuming 100% efficacy over the lifetime) in Uganda. Costs included the vaccine program (dosage and delivery) costs over a 10-year period and cervical cancer costs over the lifetimes of the current population of Ugandan women. Health outcomes included number of cervical cancer cases and disability-adjusted life years (DALYs). Incremental cost-effectiveness ratios (i.e., cost per DALY averted) were calculated and compared against the Ugandan per-capita gross domestic product. ResultsRoutine one-dose HPV vaccination of 9-year-old girls required substantial upfront investment but was cost-saving compared to no vaccination when accounting for the cost-offsets from future cancers averted. Forty years after initiating routine vaccination and depending on assumptions of vaccine waning, one-dose HPV vaccination with equivalent coverage (70%) averted 15–16% of cervical cancer cases versus 21% with two-dose vaccination but required only half the upfront economic investment. Vaccination with two doses had an attractive cost-effectiveness profile except if one-dose vaccination enabled higher coverage (90% vs. 70%) and did not wane. ConclusionsOne-dose HPV vaccination resulted in cost-savings compared to no vaccination and could be cost-effective compared to two-dose vaccination if protection is longstanding and higher coverage can be achieved.

Highlights

Cervical cancer is caused by persistent infection with one of 13 sexually transmitted high-risk human papillomavirus (HPV) genotypes [1]
Compared with a scenario of no HPV vaccination, the number of cervical cancer cases averted with routine one-dose HPV vaccination was projected to increase over time and was greater at longer duration of protection associated with a one-dose schedule (Fig. 2a)
Even when including herd immunity benefits to unvaccinated cohorts of men and women, there was a considerable time delay ($30 years) between initiation of routine 9-year-old HPV vaccination and impact on cervical cancer cases averted at the population level (Fig. 2a)

Summary

Introduction

Cervical cancer is caused by persistent infection with one of 13 sexually transmitted high-risk human papillomavirus (HPV) genotypes [1]. Compared with a two-dose HPV vaccination schedule, one-dose HPV vaccination could potentially reduce programs costs, ease administration, enable the delivery of multi-cohort vaccination, and increase HPV vaccine program adoption in populations with limited access to healthcare and a high burden of cervical cancer. Guidelines for prophylactic human papillomavirus (HPV) vaccination recommend two doses for girls ages 9–14 years, several studies have demonstrated similar protection with one dose. Results: Routine one-dose HPV vaccination of 9-year-old girls required substantial upfront investment but was cost-saving compared to no vaccination when accounting for the cost-offsets from future cancers averted. Forty years after initiating routine vaccination and depending on assumptions of vaccine waning, one-dose HPV vaccination with equivalent coverage (70%) averted 15–16% of cervical cancer cases versus 21% with two-dose vaccination but required only half the upfront economic investment.

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