# Single-dose HPV vaccination in the United States — a multi-modeling analysis

## TL;DR

Switching to a single-dose HPV vaccine in the U.S. is projected to maintain significant reductions in cervical cancer, even with lower vaccine efficacy assumptions.

## Contribution

This study provides a multi-modeling analysis of the long-term health impact of switching to single-dose HPV vaccination in the U.S.

## Key findings

- Maintaining two-dose or switching to a non-inferior single-dose HPV vaccination is projected to nearly eliminate HPV-16 infections and reduce cervical cancer by over 90%.
- Scenarios with lower efficacy or waning protection showed minimal increases in cervical cancer incidence and no delay in elimination timelines.

## Abstract

Evidence supporting the non-inferior efficacy of single-dose human papillomavirus (HPV) vaccination has prompted reconsideration of existing multi-dose HPV vaccination schedules. We evaluated the long-term health impact of adopting single-dose HPV vaccination in the United States to inform policy deliberations.

We applied two validated individual-based simulation models of HPV transmission and cervical cancer to project the impact of switching from a two-dose to a single-dose HPV vaccination schedule in 2025 in the context of historical HPV vaccination uptake in the United States. Four scenarios were simulated: continuation of two-dose vaccination (or equivalent single-dose efficacy of 98%) and three alternative pessimistic single-dose strategies with lower vaccine efficacy (90%) and/or duration of protection (average of 25 years). Outcomes included age-standardized incidence rates of HPV-16 infection and cervical cancer from years 2005–2099. Additional analyses examined effects under lower vaccination coverage observed in select U.S. regions.

Maintaining two doses or switching to a non-inferior single-dose HPV vaccination schedule was projected to nearly eliminate HPV-16 infections and reduce cervical cancer incidence by over 90% by the end of the century. Scenarios assuming a lower efficacy or waning protection showed increases in cervical cancer incidence of less than 2 percentage points decades after a switch to single-dose vaccination with no impact on the timeframe to cervical cancer elimination.

Switching to a single-dose HPV vaccination schedule is projected to maintain reductions in cervical cancer, even under pessimistic efficacy and durability assumptions. Continued monitoring of single-dose HPV vaccine efficacy over time remains critical.

PATH on behalf of the Single-Dose HPV Vaccine Evaluation Consortium; 10.13039/100000865Bill and Melinda Gates Foundation (grant No. OPP48979), and the 10.13039/100000002US National Institutes of Health/10.13039/100000054National Cancer Institute (Grant Number U01 CA253912).