FC 09-01THREE-YEAR EFFICACY OF THE QUADRIVALENT HPV VACCINE IN A COHORT OF HIV-POSITIVE WOMEN

05. HPV prophylactic vaccines
E. Mcclymont 1, M. Lee 1, J. Raboud 2, S. Blitz 2, F. Coutlée 3, S. Walmsley 4, N. Lipsky 5, D. Money 1.
1University of British Columbia (Canada), 2University Health Network (Canada), 3University of Montreal (Canada), 4University of Toronto (Canada), 5Women's Health Research Institute (Canada)

Background / Objectives

To assess the efficacy of the qHPV vaccine at 3 years in our cohort of HIV-positive women. 


Methods

HIV-positive females participating in a multi-centre study of the qHPV vaccine were administered three doses at 0, 2 and 6 months. Demographic and clinical data were collected as well as samples for cervical cytology, classified by Bethesda criteria, and HPV DNA tested by Linear array assay. Persistent qHPV, genital warts and CIN2+ were assessed. Persistent cases of qHPV were defined as new HPV 6/11/16/18 that remained present in samples from ≥2 consecutive visits or as qHPV present in the last sample. 

Two-year data was compared to findings in HIV-negative women to provide context to our results. To improve comparability of the cohorts, HIV-positive women with history of genital warts, cervical disease and cervical procedure were excluded as these were exclusion criteria among the HIV-negative women. A composite endpoint comprised of the three previous endpoints was utilized. 


Results

278 females were eligible for the intention-to-treat (ITT) population (≥1 dose of vaccine, ≥1 follow-up visit). At first vaccination, median age was 39 years (IQR: 34-45), median CD4 count was 499/mm3 (IQR: 380-684), median CD4 nadir was 230/mm3 (IQR: 120-337) and 72% had a suppressed HIV viral load (<50 copies/mL). Median follow-up was 3.2 years. In the per-protocol efficacy (PPE) population (3 doses of vaccine within 1 year, ≥1 follow-up beyond month 7, naive to the relevant qHPV type), persistent qHPV = 0.9 per 100 person-years (95% CI: 0.4-1.8), genital warts =1.0 per 100 person-years (95% CI: 0.4-2.0), CIN2+ = 0 per 100 person-years.

Within 2-year follow-up of HIV-positive women, composite endpoint incidences in the PPE, NRT and ITT groups were 1.4, 2.3 and 3.7 per 100 person-years, respectively. Among HIV-negative vaccinated women1, incidences were 0.1, 0.5 and 2.7 per 100 person-years. Among HIV-negative unvaccinated women1, incidences were 1.5, 2.0, 3.9 per 100 person-years. 


Conclusion

This study demonstrates overall low rates of vaccine failure with low rates of infection and/or disease. However, the rates of qHPV-related disease were notably higher than rates in vaccinated HIV-negative women based on published studies and similar to rates in unvaccinated HIV-negative women.  


References

1Muñoz N et al. Lancet. 2009; 373: 1949-57.