Cost-effectiveness of tenofovir gel in urban South Africa: model projections of HIV impact and threshold product prices

BMC Infectious Diseases

Charlotte H Watts⁴  Peter Vickerman⁴  Helen Rees¹  Thomas Mertenskoetter³  Sinead Delany-Moretlwe¹  Gesine Meyer-Rath²  Lori Heise⁴  Andrew P Cox⁴  Anna M Foss⁴  Fern Terris-Prestholt⁴ 

[1] Wits Reproductive Health and HIV Research Institute, Johannesburg, South Africa;Center for Global Health and Development, Boston University, Boston, USA;International Partnership for Microbicides, Silver Spring, MD, USA;London School of Hygiene & Tropical Medicine, London, UK

关键词: Pre-exposure prophylaxis (PreP);    ARV-based prevention;    Tenofovir;    Economic analysis;    Introduction of new technologies;    South Africa;    Microbicides;    Cost-effectiveness;    Modelling;    HIV;   

Others  :  1135060
DOI  :  10.1186/1471-2334-14-14

 received in 2013-03-21, accepted in 2013-12-24,  发布年份 2014

【 摘 要 】

Background

There is urgent need for effective HIV prevention methods that women can initiate. The CAPRISA 004 trial showed that a tenofovir-based vaginal microbicide had significant impact on HIV incidence among women. This study uses the trial findings to estimate the population-level impact of the gel on HIV and HSV-2 transmission, and price thresholds at which widespread product introduction would be as cost-effective as male circumcision in urban South Africa.

Methods

The estimated ‘per sex-act’ HIV and HSV-2 efficacies were imputed from CAPRISA 004. A dynamic HIV/STI transmission model, parameterised and fitted to Gauteng (HIV prevalence of 16.9% in 2008), South Africa, was used to estimate the impact of gel use over 15 years. Uptake was assumed to increase linearly to 30% over 10 years, with gel use in 72% of sex-acts. Full economic programme and averted HIV treatment costs were modelled. Cost per DALY averted is estimated and a microbicide price that equalises its cost-effectiveness to that of male circumcision is estimated.

Results

Using plausible assumptions about product introduction, we predict that tenofovir gel use could lead to a 12.5% and 4.9% reduction in HIV and HSV-2 incidence respectively, by year 15. Microbicide introduction is predicted to be highly cost-effective (under $300 per DALY averted), though the dose price would need to be just $0.12 to be equally cost-effective as male circumcision. A single dose or highly effective (83% HIV efficacy per sex-act) regimen would allow for more realistic threshold prices ($0.25 and $0.33 per dose, respectively).

Conclusions

These findings show that an effective coitally-dependent microbicide could reduce HIV incidence by 12.5% in this setting, if current condom use is maintained. For microbicides to be in the range of the most cost-effective HIV prevention interventions, product costs will need to decrease substantially.

【 授权许可】

   
2014 Terris-Prestholt et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 2.

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