Article Text


Clinical sciences oral session 2: Genital Human Papillomaviruses & Trichomoniasis
O3-S2.01 Long-term efficacy of human papillomavirus vaccination against CIN3 and invasive cervical carcinoma: a registry based Passive follow-up of the phase III trial (PATRICIA)
  1. J Paavonen1,
  2. M Lehtinen2,
  3. M Rana3,
  4. D Apter4,
  5. T Luostarinen5,
  6. E Pukkala5
  1. 1Helsinki University Hospital
  2. 2University of Tamepre Tampere, Finland
  3. 3Universitu of Tampere, Finland
  4. 4Family Federation of Finland, Finland
  5. 5Finnish Cancer Registry, Finland


Background While phase 3 trials have shown that vaccination against human papillomavirus (HPV) types 16 and 18 prevents persistent HPV type 16 and 18 infections and most high-risk HPV type positive cervical intraepithelial neoplasia (CIN) grade 2+ lesions, long-term follow-up of the phase 3 cohorts is needed to demonstrate that HPV16/18 vaccination prevents CIN3 and invasive cervical carcinoma (CIN3+).

Methods We used data from the Finnish Cancer Registry for passive follow-up of cluster (age-cohort) and individually randomised cohorts of women born in 1984–1989 to assess incidence rates of CIN3+ in HPV16/18 vaccinated Finnish cohort of the bivalent HPV 16/18 vaccine PATRICIA trial participants (N=2404) and a reference cohort (N=7049) enrolled from the same communities. Six months after the Phase III trial was closed in 2009 the cohorts were linked with the Finnish Cancer Registry.

Results and Conclusions A pilot study in 2009 showed that the baseline incidence of CIN3+ was 41 per 100 000 women years in the reference cohort. Knowing that CIN3+ incidence rapidly increases as the cohorts age, the baseline incidence yields 80% power to show 70% vaccine efficacy against CIN3+ in just 5 years. The phase 3 trial included intensive clinical follow-up and thorough health education and counselling which may have modified subsequent risk of cervical neoplasia in all study participants, the incidence rates of CIN3+ need to be validated in a cohort not exposed to any clinical intervention. Preliminary data from such comparison of the incidence rates during passive follow-up the PATRICIA study participants (comprising 50 000 women years) and the reference cohort will be reported.

Statistics from

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.