HPV infections and cytologic abnormalities in vaccinated women 21-34 years of age: Results from the baseline phase of the Onclarity trial.

OBJECTIVES: Countries with school-based human papillomavirus (HPV) vaccination have seen significant reductions in vaccine-targeted HPV infections, cytologic abnormalities, and high-grade cervical intraepithelial neoplasia (≥CIN2). However, the impact of HPV vaccination in the United States (where vaccination is largely opportunistic) may be less due to lower coverage rates and vaccination in patients at ages beyond the recommended routine vaccination age.

METHODS: The Onclarity trial enrolled 33,858 subjects ≥21 years who were screened with cytology and the BD Onclarity HPV Assay. HPV positive women or those with cytologic abnormalities underwent colposcopy and biopsy. The prevalence of HPV, cytologic abnormalities, and ≥CIN2 was compared in a subset of 14,153, vaccinated and unvaccinated women, 21-34 years. Results were compared by vaccination status; Mantel-Haenszel analysis was performed to determine the association between vaccination status and prevalence, adjusting for age.

RESULTS: The prevalence of overall HPV, HPV16, 18, 31, and 33/58 were all lower in vaccinated women for each age group; a significant difference (p < 0.001) was observed in vaccinated women for all ages combined. Cytologic low-grade squamous intraepithelial lesion (LSIL) or worse was lower in vaccinated women (p = 0.021), as was ≥CIN2 prevalence associated with HPV 16 or 18 (p = 0.011).

CONCLUSIONS: Women with a prior history of HPV vaccination have a lower prevalence of any high-risk HPV, HPV 16, 18, 31, and 33/58; a cytology result of ≥LSIL, and ≥CIN2 associated with HPV 16/18 compared to unvaccinated women. A lower HPV prevalence in older, vaccinated women suggests that "catch-up" vaccination provides benefit.