Rochelle Walensky, MD, MPH, who has published widely on the cost effectiveness of HIV interventions domestically and globally, offered a plenary presentation on the subject at the 18th Conference on Retroviruses and Opportunistic Infections in Boston Tuesday morning.
The World Health Organization (WHO) has developed criteria that calls a cost-per-year-of-life-saved that is less than or equal to the gross national product (GNP) of a country very cost effective, with a cost-per-year-of-life-saved up to three times the GNP cost effective. There has been some criticism of this algorithm, since it would seem to codify the notion that lives in wealthier countries are worth more than those in poor countries. Cost-effectiveness analyses are about measuring population, not individual benefits of interventions. But as Walensky noted in her talk, “Economic efficiencies should be just one of many considerations in establishing policy.” The other issue about this measure arises when the resources for the intervention are being supplied by donors and not financed by the country. For instance, in Mozambique, 98 percent of all funding for HIV comes from donors and 95 percent of resources for HIV in Malawi come from donors. Is this an appropriate measure in these instances? No alternative measure has been proposed.
Walensky cited some examples of cost-effectiveness research and a number of the studies were done by her own group at Harvard. Just yesterday, her group presented a late breaker abstract looking at the cost-effectiveness of pre-exposure prophylaxis (PrEP) in South Africa if offered to heterosexual women. The study estimated funding for PrEP drugs in South Africa as $44 annually and PrEP was determined to be cost effective, very cost effective, and in some cases, even cost saving. Important variables in the study were the price of drugs, and the prevalence and risk in the target population.
Walensky also reported on findings from her group from an analysis of the newest WHO guidelines and antiretroviral therapy (ART). They looked at three important changes in the guidelines from the perspective of maximizing survival and cost-effectiveness. Early ART initiation is one such change – with the new recommendation to start being when a patient’s CD4 count moves below 350 instead of the 200 identified as the threshold in the earlier guidelines. The move to 350 has a cost-effectiveness ratio of $610 per year of life saved. While earlier ART increases earlier survival, the availability of additional treatment regimens increases late survival at a cost effectiveness ratio of $2,370 per year of life saved. The switch from the HIV medication D4T to tenofovir had a cost effectiveness ratio of $1,140 per year of life saved.
Walensky also offered cost-effectiveness data on the prevention of mother-to-child transmission (PMTCT) and noted that ART for PMTCT had a cost-effectiveness ratio of $7,200 per year of life saved and was determined to be very cost-effective to cost-saving depending on program efficiency, scale and other factors.