RESUMO
BACKGROUND: In Chile, significant reductions in cervical cancer incidence and mortality have been observed due to implementation of a well-organized screening program. However, it has been suggested that the inclusion of human papillomavirus (HPV) vaccination for young adolescent women may be the best prospect to further reduce the burden of cervical cancer. This cost-effectiveness study comparing two available HPV vaccines in Chile was performed to support decision making on the implementation of universal HPV vaccination. METHODS: The present analysis used an existing static Markov model to assess the effect of screening and vaccination. This analysis includes the epidemiology of low-risk HPV types allowing for the comparison between the two vaccines (HPV-16/18 AS04-adjuvanted vaccine and the HPV-6/11/16/18 vaccine), latest cross-protection data on HPV vaccines, treatment costs for cervical cancer, vaccine costs and 6% discounting per the health economic guideline for Chile. RESULTS: Projected incremental cost-utility ratio (ICUR) and incremental cost-effectiveness ratio (ICERs) for the HPV-16/18 AS04-adjuvanted vaccine was 116 United States (US) dollars per quality-adjusted life years (QALY) gained or 147 US dollars per life-years (LY) saved, while the projected ICUR/ICER for the HPV-6/11/16/18 vaccine was 541 US dollars per QALY gained or 726 US dollars per LY saved. Introduction of any HPV vaccine to the present cervical cancer prevention program of Chile is estimated to be highly cost-effective (below 1X gross domestic product [GDP] per capita, 14278 US dollars). In Chile, the addition of HPV-16/18 AS04-adjuvanted vaccine to the existing screening program dominated the addition of HPV-6/11/16/18 vaccine. In the probabilistic sensitivity analysis results show that the HPV-16/18 AS04-adjuvanted vaccine is expected to be dominant and cost-saving in 69.3% and 77.6% of the replicates respectively. CONCLUSIONS: The findings indicate that the addition of any HPV vaccine to the current cervical screening program of Chile will be advantageous. However, this cost-effectiveness model shows that the HPV-16/18 AS04-adjuvanted vaccine dominated the HPV-6/11/16/18 vaccine. Beyond the context of Chile, the data from this modelling exercise may support healthcare policy and decision-making pertaining to introduction of HPV vaccination in similar resource settings in the region.
Assuntos
Alphapapillomavirus/imunologia , Análise Custo-Benefício , Custos de Cuidados de Saúde , Infecções por Papillomavirus/economia , Vacinas contra Papillomavirus/economia , Neoplasias do Colo do Útero/economia , Vacinação/economia , Adjuvantes Imunológicos/economia , Criança , Chile , Custos e Análise de Custo , Proteção Cruzada , Feminino , Papillomavirus Humano 11/imunologia , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/imunologia , Papillomavirus Humano 6/imunologia , Humanos , Cadeias de Markov , Modelos Teóricos , Infecções por Papillomavirus/prevenção & controle , Infecções por Papillomavirus/virologia , Anos de Vida Ajustados por Qualidade de Vida , Neoplasias do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/virologiaRESUMO
BACKGROUND: Human papillomavirus (HPV) vaccination offers potential for primary prevention of HPV-related pre-cancers and cancers as demonstrated in clinical trials. Mathematical models have estimated the potential real-life impact of vaccination on the burden of cervical cancer (CC). However, these are restricted to evaluations in a limited number of countries. METHODS: Potential decline in CC cases and deaths with the AS04-adjuvanted HPV-16/18 vaccine of young girls naïve to HPV, was estimated at steady-state (vaccine coverage: 0-100%) based on clinical trial and country-specific incidence data. Data on vaccine efficacy were taken from the end of study PATRICIA trial of the AS04-adjuvanted HPV-16/18 vaccine. The numbers of cases and deaths due to HPV-16/18 were estimated and compared with those due to any HPV type to estimate the additional cases prevented. This difference estimates CC cases and deaths avoided due to protection against non-vaccine HPV types. Cost-offsets due to reductions in CC treatment were estimated for five countries (Brazil, Canada, Italy, Malaysia and South African Republic) using country-specific unit cost data. Additionally, cervical intraepithelial neoplasia grade 2 or 3 (CIN2/3)-related burden (cases and treatment costs) prevented by vaccination were estimated for two countries (Italy and Malaysia). RESULTS: HPV vaccination could prevent a substantial number of CC cases and deaths in countries worldwide, with associated cost-offsets due to reduced CC treatment. Cross-protection increased the estimated potential number of CC cases and deaths prevented by 34 and 18% in Africa and Oceania, respectively. Moreover, vaccination could result in a substantial reduction in the number of CIN2/3 lesions and associated costs. CONCLUSION: HPV vaccination could reduce the burden of CC and precancerous lesions in countries worldwide, part of disease burden reduction being related to protection against non HPV-16/18 related types.
Assuntos
Vacinação em Massa/economia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/uso terapêutico , Neoplasias do Colo do Útero/prevenção & controle , Canadá , Efeitos Psicossociais da Doença , Análise Custo-Benefício , Feminino , Alemanha , Humanos , México , Infecções por Papillomavirus/economia , África do Sul , Tailândia , Neoplasias do Colo do Útero/economia , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/economia , Displasia do Colo do Útero/mortalidade , Displasia do Colo do Útero/prevenção & controle , Displasia do Colo do Útero/virologiaRESUMO
BACKGROUND: Screening and vaccination against human papillomavirus (HPV) can protect against cervical cancer. Neither alone can provide 100% protection. Consequently it raises the important question about the most efficient combination of screening at specified time intervals and vaccination to prevent cervical cancer. OBJECTIVE: Our objective was to identify the mix of cervical cancer prevention strategies (screening and/or vaccination against HPV) that achieves maximum reduction in cancer cases within a fixed budget. METHODS: We assessed the optimal mix of strategies for the prevention of cervical cancer using an optimization program. The evaluation used two models. One was a Markov cohort model used as the evaluation model to estimate the costs and outcomes of 52 different prevention strategies. The other was an optimization model in which the results of each prevention strategy of the previous model were entered as input data. The latter model determined the combination of the different prevention options to minimize cervical cancer under budget, screening coverage and vaccination coverage constraints. We applied the model in two countries with different healthcare organizations, epidemiology, screening practices, resource settings and treatment costs: the UK and Brazil. 100,000 women aged 12 years and above across the whole population over a 1-year period at steady state were included. The intervention was papanicolaou (Pap) smear screening programmes and/or vaccination against HPV with the bivalent HPV 16/18 vaccine (Cervarix® [Cervarix is a registered trademark of the GlaxoSmithKline group of companies]). The main outcome measures were optimal distribution of the population between different interventions (screening, vaccination, screening plus vaccination and no screening or vaccination) with the resulting number of cervical cancer and associated costs. RESULTS: In the base-case analysis (= same budget as today), the optimal prevention strategy would be, after introducing vaccination with a coverage rate of 80% in girls aged 12 years and retaining screening coverage at pre-vaccination levels (65% in the UK, 50% in Brazil), to increase the screening interval to 6 years (from 3) in the UK and to 5 years (from 3) in Brazil. This would result in a reduction of cervical cancer by 41% in the UK and by 54% in Brazil from pre-vaccination levels with no budget increase. Sensitivity analysis shows that vaccination alone at 80% coverage with no screening would achieve a cervical cancer reduction rate of 20% in the UK and 43% in Brazil compared with the pre-vaccination situation with a budget reduction of 30% and 14%, respectively. In both countries, the sharp reduction in cervical cancer is seen when the vaccine coverage rate exceeds the maximum screening coverage rate, or when screening coverage rate exceeds the maximum vaccine coverage rate, while maintaining the budget. As with any model, there are limitations to the value of predictions depending upon the assumptions made in each model. CONCLUSIONS: Spending the same budget that was used for screening and treatment of cervical cancer in the pre-vaccination era, results of the optimization program show that it would be possible to substantially reduce the number of cases by implementing an optimal combination of HPV vaccination (80% coverage) and screening at pre-vaccination coverage (65% UK, 50% Brazil) while extending the screening interval to every 6 years in the UK and 5 years in Brazil.
Assuntos
Programas de Rastreamento/métodos , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Neoplasias do Colo do Útero/prevenção & controle , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Criança , Feminino , Humanos , Cadeias de Markov , Programas de Rastreamento/economia , Pessoa de Meia-Idade , Modelos Teóricos , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Vacinas contra Papillomavirus/economia , Fatores de Tempo , Estados Unidos/epidemiologia , Neoplasias do Colo do Útero/economia , Neoplasias do Colo do Útero/virologia , Adulto JovemRESUMO
Cohort and population models estimate vaccine impact on disease events, and yield different estimates in countries with different demographic compositions. We compared administration of the new 10-valent pneumococcal Haemophilus influenzae-protein D conjugate vaccine (PHiD-CV) with no vaccination in two countries, the United Kingdom (UK) and Mexico, using two modelling strategies: a cohort model and a population model. The cohort model followed a birth cohort over a lifetime, beginning 10 years after initiation of the vaccine program, when vaccine efficacy steady state had been reached. The population model examined the country-specific population over 1 year, also beginning 10 years after initiation of the vaccine program. Both models included the same age-specific disease rates of meningitis, bacteraemia, pneumonia, and otitis media. The output variables were the numbers of specific events, with and without indirect vaccine effects. Without indirect effects, the cohort and population models produced similar results for both countries (deviation of <20% difference per output measure for most outcomes). The difference between the model types was much greater when indirect vaccine effects were included, especially in Mexico (up to 120% difference). Cohort and population modelling methods produce different results depending on the disease, the intervention, the demographic composition, and the time horizon evaluated. Results from the two model types provide different information about the impact of interventions on events: accumulated vaccine benefit for an individual in a cohort model; vaccine benefit for a whole population at a specific time point in a population model.
Assuntos
Modelos Estatísticos , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/administração & dosagem , Vacinas Pneumocócicas/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/epidemiologia , Bacteriemia/prevenção & controle , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Meningite Pneumocócica/epidemiologia , Meningite Pneumocócica/prevenção & controle , México/epidemiologia , Pessoa de Meia-Idade , Otite Média/epidemiologia , Otite Média/prevenção & controle , Pneumonia Pneumocócica/epidemiologia , Pneumonia Pneumocócica/prevenção & controle , Reino Unido/epidemiologia , Adulto JovemRESUMO
Implementation of cervical cancer (CC) vaccination in Latin America is expected to reduce the high CC burden in those countries. But the efficiency of such vaccination programs in the region still remains unknown. This study assesses the cost-effectiveness and cost-utility of introducing vaccination into the current CC disease management of five Latin American countries (Argentina, Brazil, Chile, Mexico, and Peru). The modelling results indicate that universal mass vaccination is cost-effective in the current health care setting of each country (<3x gross domestic product per capita, per country) with a substantial number of CC cases and deaths avoided in addition to an increase of quality-adjusted life years. This study will help guide the design of future clinical programmes and health-related policies. It will assist early and effective decision-making processes related to vaccine implementation in Latin America.
Assuntos
Vacinas Anticâncer/economia , Programas de Imunização/economia , Modelos Econômicos , Vacinas contra Papillomavirus/economia , Análise Custo-Benefício , Feminino , Humanos , América Latina , Infecções por Papillomavirus/prevenção & controle , Neoplasias do Colo do Útero/prevenção & controleRESUMO
Mathematical models provide valuable insights into the public health and economic impact of cervical cancer vaccination programmes. An in-depth economic analysis should explore the effects of different vaccine-related factors and vaccination scenarios (independent of screening practices) on health benefits and costs. In this analysis, a Markov cohort model was used to explore the impact of vaccine characteristics (e.g. cross-type protection and waning of immunity) and different vaccination scenarios (e.g. age at vaccination and multiple cohort strategies) on the cost-effectiveness results of cervical cancer vaccination programmes. The analysis was applied across different regions in the world (Chile, Finland, Ireland, Poland and Taiwan) to describe the influence of location-specific conditions. The results indicate that in all the different settings cervical cancer vaccination becomes more cost-effective with broader and sustained vaccine protection, with vaccination at younger ages, and with the inclusion of several cohorts. When other factors were varied, the cost-effectiveness of vaccination was most negatively impacted by increasing the discount rate applied to costs and health effects.