PRM10 - Calibration of a Cost-Effectiveness Model to Evaluate the Incorporation of a Quadrivalent HPV Types 6, 11, 16, 18 Vaccine in Argentina: Disease Burden Component

Abstract

To calibrate the disease burden component (mortality and incidence rates from cervical cancer) of a cost-effectiveness model that aims to evaluate the incorporation of a quadrivalent HPV Type 6, 11, 16, 18 vaccine in Argentina. We adapted a previously developed mathematical model (Elbasha 2010) to evaluate the health and economic impact of routine vaccination of 11 years old females. The model is a dynamic transmission model which estimates the direct and indirect (via herd immunity) health benefits of vaccination. Individuals enter the model as they are born; move between successive age groups at an age, gender and sexual activity specific rates, and exit the model as they die. A systematic search on effectiveness, local epidemiology, resource use and costs was undertaken to populate the model. Selected intermediate parameters (probability of transmitting genital HPV infection per sexual partnership by HPV genotype, and percent of females with cervical cancer that recognize their symptoms and seek treatment) were used for calibration. The perspective used was that of the health care system, with a horizontal span of 100 years and a rate of discount of 5% for costs and health effects. The model was properly calibrated with results in a range of +/- 1% as compared to national vital statistics and Globocan. The model showed an incidence of 5,285 new cases of HPV 16&18 related cervical cancers per year in Argentina and 1,511 deaths for 2013. Eighty-seven and 80% of incident cases and deaths were concentrated in the 35 to 85 age group, and a median age of death of 55 years. The model proved to be an evidence-based, internally valid tool for the assessment of the main HPV related disease burden and can serve as the basis for the further evaluation of the cost-effectiveness of HPV routine vaccination in Argentina.